Salivary Gland Secretory Carcinoma: Clinicopathologic and Genetic Characteristics of 215 Cases and Proposal for a Grading System

Baněčková M, Thompson LDR, Hyrcza MD, Vaněček T, Agaimy A, Laco J, Simpson RHW, Di Palma S, Stevens TM, Brcic L, Etebarian A, Dimnik K, Majewska H, Stárek I, O’Regan E, Salviato T, Helliwell T, Horáková M, Biernat W, Onyuma T, Michal M, Leivo I, Skalova A.
Am J Surg Pathol. 2023 Jun 1;47(6):661-677.
Salivary gland secretory carcinoma (SC), previously mammary analog SC, is a low-grade malignancy characterized by well-defined morphology and an immunohistochemical and genetic profile identical to SC of the breast. Translocation t(12;15)(p13;q25) resulting in the ETV6::NTRK3 gene fusion is a characteristic feature of SC along with S100 protein and mammaglobin immunopositivity. The spectrum of genetic alterations for SC continues to evolve. The aim of this retrospective study was to collect data of salivary gland SCs and to correlate their histologic, immunohistochemical, and molecular genetic data with clinical behavior and long-term follow-up. In this large retrospective study, we aimed to establish a histologic grading scheme and scoring system. A total of 215 cases of salivary gland SCs diagnosed between 1994 and 2021 were obtained from the tumor registries of the authors. Eighty cases were originally diagnosed as something other than SC, most frequently acinic cell carcinoma. Lymph node metastases were identified in 17.1% (20/117 cases with available data), with distant metastasis in 5.1% (6/117). Disease recurrence was seen in 15% (n=17/113 cases with available data). The molecular genetic profile showed ETV6::NTRK3 gene fusion in 95.4%, including 1 case with a dual fusion of ETV6::NTRK3 and MYB::SMR3B. Less frequent fusion transcripts included ETV6::RET (n=12) and VIM::RET (n=1). A 3-tiered grading scheme using 6 pathologic parameters (prevailing architecture, pleomorphism, tumor necrosis, perineural invasion (PNI), lymphovascular invasion (LVI), and mitotic count and/or Ki-67 labeling index) was applied. Grade 1 histology was observed in 44.7% (n=96), grade 2 in 41.9% (n=90), and grade 3 in 13.5% (n=29) of cases. Compared with low-grade and intermediate-grade SC, high-grade tumors were associated with a solid architecture, more prominent hyalinization, infiltrative tumor borders, nuclear pleomorphism, presence of PNI and/or LVI, and Ki-67 proliferative index >30%. High-grade transformation, a subset of grade 2 or 3 tumors, seen in 8.8% (n=19), was defined as an abrupt transformation of conventional SC into high-grade morphology, sheet-like growth, and a tumor lacking distinctive features of SC. Both overall survival and disease-free survival (5 and 10 y) were negatively affected by tumor grade, stage, and TNM status (each P<0.0001). SC is a low-grade malignancy with predominantly solid-microcystic growth patterns, driven by a gene fusion, most commonly ETV6::NTRK3. There is a low risk for local recurrence and a good overall long-term survival, with a low risk for distant metastasis but a higher risk for locoregional lymph node metastasis. The presence of tumor necrosis, hyalinization, PNI and/or LVI, and positive resection margins correlate with higher tumor grade, less favorable prognosis, and increased mortality. The statistical results allowed us to design a 3-tiered grading system for salivary SC.
PubMed ID: 37070739
Article Size: 2.3 MB

Clinicopathologic and Immunophenotypic Characterization of 25 Cases of Acinic Cell Carcinoma with High-Grade Transformation

Thompson LD, Aslam MN, Stall JN, Udager AM, Chiosea S, McHugh JB
Head Neck Pathol. 2016 Jun;10(2):152-60.
Acinic cell carcinoma (AiCC) with high-grade transformation is a rare variant of AiCC composed of both a conventional low-grade (LG) AiCC and a separate highgrade (HG) component. We describe here, the clinicopathologic and immunohistochemical features of 25 cases diagnosed between 1990 and 2015. Available tissue was analyzed and compared with a cohort of pure LG AiCC for the morphologic and immunophenotypic profile. Incidence was higher in females (1.8:1) than males with an overall mean age at presentation of 63.2 years. All tumors occurred in the parotid gland including 76 % with facial nerve trunk and branches involvement. Most patients were treated with extensive resection and adjuvant therapy. Local recurrence or distant metastasis occurred in most patients, with 72.7 % dead with disease (mean 2.9 years) and 3 patients alive with disease (mean 2.4 years). The majority of the tumors were composed of a LG microcystic AiCC and a HG component consisting of invasive lobules of undifferentiated cells with predominantly solid, cribriform, and glandular patterns. Acinic differentiation was still present in HG areas but aggressive features such as perineural invasion (76 %), lymphovascular invasion (62 %), positive margins (72 %), high mitotic rate, atypical mitoses and/or comedonecrosis (86 %) were easily identified. Compared to the pure LG AiCC, the cases with HG transformation showed significantly increased expression of cyclin-D1, p53 and Ki-67. Most HG areas of AiCC expressed membranous b-catenin (92 %) and were negative for p63 (three cases were focally positive), S100, SMA, androgen, and estrogen receptors. DOG1 expression was present in all LG AiCC tested with retained expression in 91 % of cases with HG transformation, supporting acinic differentiation in the HG foci. Recognition of AiCC with high-grade transformation is imperative as more aggressive clinical management is warranted.
PubMed ID: 26245749
Article Size: 6 MB
 
 
 
 

The HTN3-MSANTD3 Fusion Gene Defines a Subset of Acinic Cell Carcinoma of the Salivary Gland.

Andreasen S, Varma S, Barasch N, Thompson LDR, Miettinen M, Rooper L, Stelow EB, Agander TK, Seethala RR, Chiosea SI, Homøe P, Wessel I, Larsen SR, Erentaite D, Bishop JA, Ulhøi BP, Kiss K, Melchior LC, Pollack JR, West RB.
Am J Surg Pathol. 2019 Apr;43(4):489-496
The spectrum of tumors arising in the salivary glands is wide and has recently been shown to harbor a network of tumor-specific fusion genes. Acinic cell carcinoma (AciCC) is one of the more frequently encountered types of salivary gland carcinoma, but it has remained a genetic orphan until recently when a fusion between the HTN3 and MSANTD3 genes was described in one case. Neither of these 2 genes is known to be implicated in any other malignancy. This study was undertaken to investigate whether the HTN3-MSANTD3 fusion is a recurrent genetic event in AciCC and whether it is a characteristic of one of its histological variants. Of the 273 AciCCs screened, 9 cases showed rearrangement of MSANTD3 by break-apart fluorescence in situ hybridization, 2 had 1 to 2 extra signals, and 1 had gain, giving a total of 4.4% with MSANTD3 aberrations. In 6 of 7 available cases with MSANTD3 rearrangement, the HTN3-MSANTD3 fusion transcript was demonstrated with real-time polymerase chain reaction . Histologically, all fusion-positive cases were predominantly composed of serous tumor cells growing in solid sheets, with serous tumor cells expressing DOG-1 and the intercalated duct-like cell component being CK7 positive and S-100 positive in 6/9 cases. All but one case arose in the parotid gland, and none of the patients experienced a recurrence during follow-up. In contrast, the case with MSANTD3 gain metastasized to the cervical lymph nodes and lungs. In conclusion, we find the HTN3-MSANTD3 gene fusion to be a recurrent event in AciCC with prominent serous differentiation and an indolent clinical course.
PubMed ID: 30520817
Article Size: <1 MB
 

Salivary acinic cell carcinoma: reappraisal and update

Vander Poorten V, Triantafyllou A, Thompson LD, Bishop J, Hauben E, Hunt J, Skalova A, Stenman G, Takes RP, Gnepp DR, Hellquist H, Wenig B, Bell D, Rinaldo A, Ferlito A.
Eur Arch Otorhinolaryngol. 2016 Nov;273(11):3511-3531.
Epidemiologic and clinicopathologic features, therapeutic strategies, and prognosis for acinic cell carcinoma of the major and minor salivary glands are critically reviewed. We explore histopathologic, histochemical, electron microscopic and immunohistochemical aspects and discuss histologic grading, histogenesis, animal models, and genetic events. In the context of possible diagnostic difficulties, the relationship to mammary analog secretory carcinoma is probed and a classification is suggested. Areas of controversy or uncertainty, which may benefit from further investigations, are also highlighted.
PubMed ID: 26685679
Article Size: 5.22 MB
 

Top Ten Differentials to Mull Over for Head and Neck Myoepithelial Neoplasms

Thompson LDR, Xu B.
Head Neck Pathol. 2023 Mar 16. doi: 10.1007/s12105-022-01502-0. Online ahead of print.
BACKGROUND: Myoepithelial neoplasms of the salivary gland are benign or malignant neoplasms composed exclusively of neoplastic myoepithelial cells. These tumors, including the benign myoepithelioma and the malignant counterpart myoepithelial carcinoma, exhibit a wide range of cytomorphologic features and architectural patterns.
METHODS: Review.
RESULTS: Myoepithelial cells can be epithelial, plasmacytoid, clear cell, spindle cell, and/or oncocytic cell, arranging as trabeculae, solid sheets, nests, cords, and/or single cells. A stromal component is commonly but not universally present, Therefore, their differential diagnoses are quite broad, including salivary gland neoplasms especially those with a myoepithelial component, plasmacytoma, melanoma, and various mesenchymal tumors.
CONCLUSION: In this review, we summarize the characteristic histologic features, useful immunohistochemical panel, and common molecular alterations of myoepithelial tumors and their top differential diagnoses. A logical stepwise algorithmic approach and an immunohistochemical panel to include multiple myoepithelial markers are essential to establish the correct diagnosis.
PubMed ID: 36928733
Article Size: 5.2 MB

Salivary gland acinic cell carcinoma.

Thompson LD.
Ear Nose Throat J. 2010 Nov;89(11):530-2.
FIRST PARAGRAPH: Acinic cell carcinoma (AcCC) is a malignant epithelial salivary gland neoplasm that demonstrates serous acinar cell differentiation with cytoplasmic zymogen secretory granules. While serous-type cells tend to predominate, ductal cells are also part of this neoplasm. There are a few cases that are thought to be related to radiation exposure. AcCC accounts for about 6% of all salivary gland tumors and 10 to 12% of all malignant salivary gland tumors. Patients present at a wide range of ages (mean: 40s). Children are also affected, as AcCC is the second most common neoplasm in the pediatric age group after mucoepidermoid carcinoma. Overall, females are more affected than males by a ratio of 3:2.
PubMed ID: 21086276
Article Size: <1 MB

Sclerosing Polycystic Adenoma.

Bishop JA, Thompson LDR.
Surg Pathol Clin. 2021 Mar;14(1):17-24. doi: 10.1016/j.path.2020.09.004.
Sclerosing polycystic adenoma (SPA) is the more appropriate name for sclerosing polycystic adenosis. SPA is an uncommon salivary gland lesion with a constellation of unusual histologic findings that were originally interpreted as analogous to breast fibrocystic changes. The histologic findings in SPA include fibrosis, cystic alterations, apocrine metaplasia, and proliferations of ducts, acini, and myoepithelial cells in variable proportions. Because of its unusual mixed histology, SPA may be confused with a variety of lesions, ranging from reactive conditions to benign or even malignant neoplasms. The features of SPA are reviewed, with an emphasis on resolving its differential diagnosis.
PubMed ID: 33526220
Article Size: 8.25 MB

Sclerosing Polycystic “Adenosis” of Salivary Glands: A Neoplasm Characterized by PI3K Pathway Alterations More Correctly Named Sclerosing Polycystic Adenoma.

Bishop JA, Gagan J, Baumhoer D, McLean-Holden AL, Oliai BR, Couce M, Thompson LDR.
Head Neck Pathol. 2020 Sep;14(3):630-636. doi: 10.1007/s12105-019-01088-0. Epub 2019 Oct 11.
Sclerosing polycystic adenosis (SPA) is a rare benign salivary gland lesion that usually arises from the parotid gland. SPA was originally interpreted to be a non-neoplastic alteration analogous to fibrocystic changes of the breast, but now there is uncertainty about whether it may represent a neoplasm. SPA often contains intraductal proliferations with an appearance similar to ductal neoplasia of the breast, and one study reported X-chromosome inactivation using polymorphisms of the human androgen receptor (Skalova et al., in AJSP 30:939-944, 2006). We investigated the genetics of SPA through targeted next generation sequencing (NGS). Four cases of SPA were retrieved from the authors’ consultation files. A custom, targeted NGS panel including 1425 cancer-related genes was performed on all cases, followed by immunohistochemistry for PTEN. All four cases developed in females, ranging from 40 to 69 years (mean 52.5 years), affecting the parotid (n = 3) and submandibular glands (n = 1). All cases exhibited characteristic histologic features of SPA: well-circumscribed lesions with fibrosis and an admixture of ducts, myoepithelial cells and acinar cells, the latter containing brightly eosinophilic intracytoplasmic granules. Two cases had intraductal apocrine epithelial proliferations. By targeted NGS, loss-of-function mutations in PTEN were revealed in all 4 cases. In addition, 2 of 4 cases harbored PIK3CA mutations and 2 of 4 possessed PIK3R1 alterations; one case lacked both PIK3CA and PIK3R1 mutations. PTEN expression by immunohistochemistry was lost in the ductal and acinar elements but not the myoepithelial cells in all cases. SPA is characterized by genetic alterations in the PI3K pathway, with PTEN mutations seen most frequently. This molecular profile is similar to salivary duct carcinoma and the apocrine variant of intraductal carcinoma (i.e., salivary duct carcinoma-in situ). PI3K pathway alterations were found in cases both with and without intraductal apocrine proliferations, and PTEN immunohistochemistry suggested that the ductal and acinar cells, but not myoepithelial cells, were affected. Taken together, these findings strongly support that SPA is a neoplasm, more correctly named “sclerosing polycystic adenoma.” The salivary duct carcinoma-like genetic alterations, coupled with the fact that the surrounding myoepithelial cells appear to be non-neoplastic, suggest a close relationship between SPA and apocrine intraductal carcinoma.
PubMed ID: 31605313
Article Size: 1.9 MB

Expanding the Molecular Spectrum of Secretory Carcinoma of Salivary Glands With a Novel VIM-RET Fusion

Skálová A, Banečkova M, Thompson LDR, Ptáková N, Stevens TM, Brcic L, Hyrcza M, Michal M Jr, Simpson RHW, Santana T, Michal M, Vaněček T, Leivo I.
Am J Surg Pathol. 2020 Oct;44(10):1295-1307. doi: 10.1097/PAS.0000000000001535.
BACKGROUND: Secretory carcinoma (SC), originally described as mammary analogue SC, is a predominantly low-grade salivary gland neoplasm characterized by a recurrent t(12;15)(p13;q25) translocation, resulting in ETV6-NTRK3 gene fusion. Recently, alternative ETV6-RET, ETV6-MAML3, and ETV6-MET fusions have been found in a subset of SCs lacking the classic ETV6-NTRK3 fusion transcript, but still harboring ETV6 gene rearrangements.
DESIGN: Forty-nine cases of SC revealing typical histomorphology and immunoprofile were analyzed by next-generation sequencing using the FusionPlex Solid Tumor kit (ArcherDX). All 49 cases of SC were also tested for ETV6, RET, and NTRK3 break by fluorescence in situ hybridization and for the common ETV6-NTRK3 fusions using reverse transcription polymerase chain reaction.
RESULTS: Of the 49 cases studied, 37 (76%) occurred in the parotid gland, 7 (14%) in the submandibular gland, 2 (4%) in the minor salivary glands, and 1 (2%) each in the nasal mucosa, facial skin, and thyroid gland. SCs were diagnosed more frequently in males (27/49 cases; 55%). Patients’ age at diagnosis varied from 15 to 80 years, with a mean age of 49.9 years. By molecular analysis, 40 cases (82%) presented the classic ETV6-NTRK3 fusion, whereas 9 cases (18%) revealed an alternate fusion. Of the 9 cases negative for the ETV6-NTRK3 fusion, 8 cases presented with ETV6-RET fusion. In the 1 remaining case in the parotid gland, next-generation sequencing analysis identified a novel VIM-RET fusion transcript. In addition, the analysis indicated that 1 recurrent high-grade case in the submandibular gland was positive for both ETV6-NTRK3 and MYB-SMR3B fusion transcripts.
CONCLUSIONS: A novel finding in our study was the discovery of a VIM-RET fusion in 1 patient with SC of the parotid gland who could possibly benefit from RET-targeted therapy. In addition, 1 recurrent high-grade case was shown to harbor 2 different fusions, namely, ETV6-NTRK3 and MYB-SMR3B. The expanded molecular spectrum provides a novel insight into SC oncogenesis and carries important implications for molecular diagnostics, as this is the first SC-associated translocation with a non-ETV6 5′ fusion partner. This finding further expands the definition of SC while carrying implications for selecting the appropriate targeted therapy.
PubMed ID: 32675658
Article Size: 1.1 MB

Molecular Characterization of Apocrine Salivary Duct Carcinoma

Chiosea SI, Williams L, Griffith CC, Thompson LD, Weinreb I, Bauman JE, Luvison A, Roy S, Seethala RR, Nikiforova MN.
Am J Surg Pathol. 2015 Jun;39(6):744-52.
Contemporary classification and treatment of salivary duct carcinoma (SDC) require its thorough molecular characterization. Thirty apocrine SDCs were analyzed by the Ion Ampliseq Cancer HotSpot panel v2 for mutations in 50 cancer-related genes. Mutational findings were corroborated by immunohistochemistry (eg, TP53, BRAF, ?-catenin, estrogen, and androgen receptors) or Sanger sequencing/SNaPshot polymerase chain reaction. ERBB2 (HER2), PTEN, FGFR1, CDKN2A/P16, CMET, EGFR, MDM2, and PIK3CA copy number changes were studied by fluorescence in situ hybridization. TP53 mutations (15/27, 56%), PTEN loss (11/29, 38%, including 2 cases with PTEN mutation), PIK3CA hotspot mutations (10/30, 33%), HRAS hotspot mutations (10/29; 34%), and ERBB2 amplification (9/29, 31%, including 1 case with mutation) represented the 5 most common abnormalities. There was no correlation between genetic changes and clinicopathologic parameters. There was substantial overlap between genetic changes: 8 of 9 cases with ERBB2 amplification also harbored a PIK3CA, HRAS, and TP53 mutation and/or PTEN loss. Six of 10 cases with PIK3CA mutation also had an HRAS mutation. These findings provide a molecular rationale for dual targeting of mitogen-activated protein kinase and phosphoinositide 3-kinase pathways in SDC. FGFR1 amplification (3/29, 10%) represents a new potential target. On the basis of studies of breast carcinomas, the efficacy of anti-ERBB2 therapy will likely be decreased in SDC with ERBB2 amplification co-occurring with PIK3CA mutation or PTEN loss. Therefore, isolated ERBB2 testing is insufficient for theranostic stratification of apocrine SDC. On the basis of the prevalence and type of genetic changes, apocrine SDC appears to resemble one subtype of breast carcinoma-‘luminal androgen receptor positive/molecular apocrine.’
PubMed ID: 25723113
Article Size: <1 MB
 
 
 
 

Frankly Invasive Carcinoma Ex-intraductal Carcinoma: Expanding on an Emerging and Perplexing Concept in Salivary Gland Tumor Pathology

McLean-Holden AC, Rooper LM, Lubin DJ, Magliocca KR, Manucha V, Sadow PM, Tobias J, Vargo RJ, Thompson LDR, Heidarian A, Weinreb I, Wenig B, Gagan J, Hernandez-Prera JC, Bishop JA.
Head Neck Pathol. 2022 Sep;16(3):657-669.
Intraductal carcinoma (IDC) of the salivary glands is an uncommon and enigmatic tumor, our understanding of which is rapidly evolving. Recent studies have demonstrated multiple IDC subtypes and consistent gene fusions, most frequently involving RET. Because IDC is a ductal proliferation surrounded by flattened myoepithelial cells, it was previously presumed to be analogous to breast ductal carcinoma in situ, but recent evidence has shown that the myoepithelial cells of fusion-positive IDC harbor the same genetic alterations of the ductal cells and are therefore neoplastic. In addition, there are rare reports of fusion-positive IDC with overt areas of irregular invasion lacking myoepithelial cells, but this phenomenon is not well documented or understood. This study aims to better characterize these frankly invasive carcinoma ex-IDC. All cases of frankly invasive carcinoma ex-IDC were obtained from the authors’ files. Inclusion criteria included a component of concurrent or antecedent IDC and/or a fusion known to be associated with IDC. Immunohistochemistry (S100, SOX10, mammaglobin, androgen receptor, p63, p40) and molecular analysis (targeted RNA sequencing or large panel DNA next generation sequencing) was performed. Clinical follow-up was obtained from medical records. Ten cases of frankly invasive carcinoma ex-IDC were identified. The tumors occurred in 8 men and 2 women ranging from 33 to 82 years (mean, 66.3). All but one case arose in the parotid gland. In 4 cases, the IDC component was intercalated duct type. It was mixed apocrine/intercalated duct in two, and in the remaining 4 cases, no residual IDC was identified. The frankly invasive carcinomas were remarkably heterogeneous, ranging from minimally to widely invasive beyond the confines of the IDC, low-grade to high-grade, with morphologies that varied from duct-forming to those having clear cell or sarcomatoid features, to frankly apocrine. The original diagnoses for these cases were (adeno) carcinoma, not otherwise specified (n = 6), salivary duct carcinoma (n = 3), and secretory carcinoma (n = 1). All cases harbored fusions: NCOA4::RET (n = 6), TRIM33::RET (n = 2), TRIM27::RET (n = 1), and STRN::ALK (n = 1). Clinically, one tumor recurred locally, cervical lymph node metastases occurred in five patients, and distant metastasis later developed in four of these patients. Our findings highlight striking diversity in frankly invasive carcinomas that arise from fusion-positive IDC, a tumor which may serve as a precursor neoplasm like pleomorphic adenoma. These carcinomas vary in their extent of invasion, grade, histologic appearances, and clinical behavior. Importantly, in contrast to pure IDC, which is believed to be indolent, many frankly invasive cases were aggressive. Because RET and ALK fusions are targetable, it is important to recognize the broad spectrum of frankly invasive carcinomas that can arise from IDC, particularly because some cases are completely overrun or recur without any recognizable IDC component. These results suggest fusion analysis may be of clinical benefit on any salivary gland (adeno) carcinoma, not otherwise specified or salivary duct carcinoma.
PubMed ID: 34985683
Article Size: 5 MB

Cervical Lymph Node Metastasis in High-Grade Transformation of Head and Neck Adenoid Cystic Carcinoma: A Collective International Review.

Hellquist H, Skálová A, Barnes L, Cardesa A, Thompson LD, Triantafyllou A, Williams MD, Devaney KO, Gnepp DR,, Bishop JA, Wenig BM, Suárez C,, Rodrigo JP,, Coca-Pelaz A, Strojan P, Shah JP, Hamoir M, Bradley PJ,, Silver CE, Slootweg PJ, Vander Poorten V,, Teymoortash A, Medina JE, Robbins KT, Pitman KT, Kowalski LP, de Bree R, Mendenhall WM, Eloy JA, Takes RP, Rinaldo A, Ferlito A.
Adv Ther. 2016 Mar;33(3):357-68.
Adenoid cystic carcinoma (AdCC) is among the most common malignant tumors of the salivary glands. It is characterized by a prolonged clinical course, with frequent local recurrences, late onset of metastases and fatal outcome. High-grade transformation (HGT) is an uncommon phenomenon among salivary carcinomas and is associated with increased tumor aggressiveness. In AdCC with high-grade transformation (AdCC-HGT), the clinical course deviates from the natural history of AdCC. It tends to be accelerated, with a high propensity for lymph node metastasis. In order to shed light on this rare event and, in particular, on treatment implications, we undertook this review: searching for all published cases of AdCC-HGT. We conclude that it is mandatory to perform elective neck dissection in patients with AdCC-HGT, due to the high risk of lymph node metastases associated with transformation.
PubMed ID: 26895332
Article Size: 3 MB
 

Salivary Mucinous Adenocarcinoma Is a Histologically Diverse Single Entity With Recurrent AKT1 E17K Mutations: Clinicopathologic and Molecular Characterization With Proposal for a Unified Classification.

Rooper LM, Argyris PP, Thompson LDR, Gagan J, Westra WH, Jordan RC, Koutlas IG, Bishop JA.
Am J Surg Pathol. 2021 Oct 1;45(10):1337-1347. doi: 10.1097/PAS.0000000000001688.
Mucin-producing salivary adenocarcinomas were historically divided into separate colloid carcinoma, papillary cystadenocarcinoma, and signet ring cell carcinoma diagnoses based on histologic pattern, but have recently been grouped together in the adenocarcinoma not otherwise specified category. It is currently unclear if these tumors represent 1 or more distinct entities and how they are related to well-circumscribed papillary mucinous lesions with recurrent AKT1 E17K mutations that were recently described as salivary intraductal papillary mucinous neoplasm. Here, we sought to evaluate the clinicopathologic and molecular features of salivary mucinous adenocarcinomas to clarify their classification. We identified 17 invasive mucin-producing salivary adenocarcinomas, 10 with a single histologic pattern, and 7 with mixed patterns. While most tumors demonstrated papillary growth (n=15), it was frequently intermixed with colloid (n=6) and signet ring (n=3) architecture with obvious transitions between patterns. All were cytokeratin 7 positive (100%) and cytokeratin 20 negative (0%). Next-generation sequencing performed on a subset demonstrated recurrent AKT1 E17K mutations in 8 cases (100%) and TP53 alterations in 7 cases (88%). Of 12 cases with clinical follow-up (median: 17 mo), 4 developed cervical lymph node metastases, all of which had colloid or signet ring components. Overall, overlapping histologic and immunohistochemical features coupled with recurrent AKT1 E17K mutations across patterns suggests that mucin-producing salivary adenocarcinomas represent a histologically diverse single entity that is closely related to tumors described as salivary intraductal papillary mucinous neoplasm. We propose a unified mucinous adenocarcinoma category subdivided into papillary, colloid, signet ring, and mixed subtypes to facilitate better recognition and classification of these tumors.
PubMed ID: 33739781
Article Size: 1 MB

Molecular Profiling of Salivary Gland Intraductal Carcinoma Revealed a Subset of Tumors Harboring NCOA4-RET and Novel TRIM27-RET Fusions: A Report of 17 cases.

Skálová A, Vanecek T, Uro-Coste E, Bishop JA, Weinreb I, Thompson LDR, de Sanctis S, Schiavo-Lena M, Laco J, Badoual C, Santana Conceiçao T, Ptáková N, Baněčkova M, Miesbauerová M, Michal M.
Am J Surg Pathol. 2018 Nov;42(11):1445-1455.
Intraductal carcinoma (IC) is the new World Health Organization designation for tumors previously called “low-grade cribriform cystadenocarcinoma” and “low-grade salivary duct carcinoma.” The relationship of IC to salivary duct carcinoma is controversial, but they now are considered to be distinct entities. IC is a rare low-grade malignant salivary gland neoplasm with features similar to mammary atypical ductal hyperplasia or ductal carcinoma in situ, that shows diffuse S100 protein and mammaglobin positivity and is only partially defined genetically. (Mammary analogue) secretory carcinoma harboring ETV6-NTRK3, and in rare cases ETV6-RET fusion, shares histomorphologic and immunophenotypical features with IC. Recently, RET rearrangements and NCOA4-RET have been described in IC, suggesting a partial genetic overlap with mammary analogue secretory carcinoma. Here, we genetically characterize the largest cohort of IC to date to further explore this relationship. Seventeen cases of IC were analyzed by next-generation sequencing using the FusionPlex Solid Tumor kit (ArcherDX). Identified fusions were confirmed using fluorescence in situ hybridization break apart and, in some cases, fusion probes, and a reverse transcription polymerase chain reaction designed specifically to the detected breakpoints. All analyzed cases were known to be negative for ETV6 rearrangement by fluorescence in situ hybridization and for ETV6-NTRK3 fusion by reverse transcription polymerase chain reaction. Next-generation sequencing analysis detected a NCOA4-RET fusion transcript joining exon 7 or 8 of NCOA4 gene and exon 12 of RET gene in 6 cases of intercalated duct type IC; and a novel TRIM27-RET fusion transcript between exons 3 and 12 in 2 cases of salivary gland tumors displaying histologic and immunohistochemical features typical of apocrine IC. A total of 47% of IC harbored a fusion involving RET. In conclusion, we have confirmed the presence of NCOA4-RET as the dominant fusion in intercalated duct type IC. A novel finding in our study has been a discovery of a subset of IC patients with apocrine variant IC harboring a novel TRIM27-RET.
PubMed ID: 30045065
Article Size: <1 MB
 

Salivary Gland Intraductal Carcinoma: How Do 183 Reported Cases Fit Into a Developing Classification.

Thompson LDR, Bishop JA.
Adv Anat Pathol. 2023 Mar 1;30(2):112-129.
Salivary gland intraductal carcinoma (IDC) is a very uncommon group of neoplasms. Many names, variations in diagnostic criteria, and newly observed molecular findings (including NCOA4::RET, TRIM27::RET, HRAS point mutations, and PIK3CA pathway alterations) have generated further confusion in being able to recognize and categorize this group of tumors. Different histologic appearances and patterns of growth suggest there is more than one tumor category, with intercalated duct, apocrine, oncocytic, and hybrid features seen. Frankly destructive invasion further complicates the category, as the name “intraductal” would suggest an “in situ” neoplasm. Recent evidence on fusion-positive IDC demonstrates the same molecular underpinnings in both the ductal and the myoepithelial cells, which aids in further separating these tumors. This article summarizes the historical group of 183 neoplasms classified under the umbrella of IDC and highlights the unique histologic, immunohistochemistry, and molecular features that may further guide nomenclature standardization and harmonization.
PubMed ID: 36040027
Article Size: 1.4 MB

NCOA4-RET and TRIM27-RET Are Characteristic Gene Fusions in Salivary Intraductal Carcinoma, Including Invasive and Metastatic Tumors: Is “Intraductal” Correct?

Skálová A, Ptáková N, Santana T, Agaimy A, Ihrler S, Uro-Coste E, Thompson LDR, Bishop JA, Baněčkova M, Rupp NJ, Morbini P, de Sanctis S, Schiavo-Lena M, Vanecek T, Michal M, Leivo I.
Am J Surg Pathol. 2019 Oct;43(10):1303-1313. doi: 10.1097/PAS.0000000000001301.
Intraductal carcinoma (IC) is the new WHO designation for tumors previously encompassed by “low-grade cribriform cystadenocarcinoma” and “low-grade salivary duct carcinoma.” The relationship of IC to salivary duct carcinoma (SDC) is controversial, even though they are considered to be distinct entities. IC is a rare low-grade malignant salivary gland neoplasm with histopathological features reminiscent of atypical ductal hyperplasia or ductal carcinoma in situ of the breast, showing diffuse S100 protein and mammaglobin positivity, while it is partially defined genetically. Recently, RET rearrangements including NCOA4-RET and TRIM27-RET have been described in IC. Here, we genetically characterize the largest cohort of IC to date (33 cases) including 8 cases with focal or widespread invasive growth and 1 case with lymph node metastasis. Thirty-three cases of IC were analyzed by next-generation sequencing (NGS) using the FusionPlex Solid Tumor kit (ArcherDX). Identified gene fusions were confirmed using fluorescence in situ hybridization break-apart and fusion probes and an reverse transcription polymerase chain reaction designed specifically for the detected breakpoints. Ten cases of SDC were analyzed for comparison using NGS panels that detect mutations and fusion transcripts. NGS analysis detected an NCOA4-RET fusion transcript in 11 cases of intercalated duct-type IC joining exon 7 or 8 of NCOA4 gene and exon 12 of the RET gene. Eight cases of IC had an invasive growth pattern, including one with widespread invasion and lymph node metastasis. Three invasive ICs harbored an NCOA4-RET fusion transcript, while 1 case was negative, and 2 cases were not analyzable. In addition, a novel TRIM27-RET fusion transcript between exon 3 of TRIM27 and exon 12 of RET was identified in 2 cases of IC with apocrine features, and one of them displayed invasive growth. Two IC cases with invasive growth harbored novel fusions TUT1-ETV5 and KIAA1217-RET, respectively. A total of 42.4% of the cases in this series of IC harbored fusions involving RET. Such fusion transcripts were not detected in any of the 10 SDC cases. We have confirmed NCOA4-RET as a predominant fusion in intercalated duct-type IC, including 3 cases with invasive growth pattern. A novel finding in our series was a case of widely invasive intercalated duct-type IC, with a single lymph node metastasis that revealed an NCOA4-RET fusion transcript. We also demonstrated that a subset of apocrine Ics harbored a TRIM27-RET gene fusion, including one case with invasive growth. In contrast, neither NCOA4-RET nor TRIM27-RET fusions were detected in any tested SDCs. Thus, the distinct molecular findings in IC and SDC support that the tumors are separate malignant salivary tumor entities. The presence of tumor-type-specific NCOA4-RET or TRIM27-RET translocations in a subset of widely invasive carcinomas with intercalated duct-like immunoprofiles suggests that a recharacterization of IC including its redesignation as “intercalated duct carcinoma, invasive or noninvasive” may be appropriate.
PubMed ID: 31162284
Article Size: <1 MB

The Myoepithelial Cells of Salivary Intercalated Duct-type Intraductal Carcinoma Are Neoplastic: A Study Using Combined Whole-slide Imaging, Immunofluorescence, and RET Fluorescence In Situ Hybridization.

Bishop JA, Rooper LM, Sangoi AR, Gagan J, Thompson LDR, Inagaki H.
Am J Surg Pathol. 2021 Apr 1;45(4):507-515. doi: 10.1097/PAS.0000000000001605.
Intraductal carcinoma (IDC) is a salivary gland tumor currently believed to be analogous to breast ductal carcinoma in situ, consisting of a complex neoplastic epithelial proliferation surrounded by a continuous layer of myoepithelial cells presumed to be native and non-neoplastic. Recent molecular insights have shown that there are at least 3 different types of IDC: (1) intercalated duct-like, with frequent NCOA4-RET fusions; (2) apocrine, with multiple mutations similar to salivary duct carcinoma; and (3) mixed intercalated duct-like and apocrine with frequent RET fusions, especially TRIM27-RET. Recent observations (eg, IDC occurring in lymph nodes) have challenged the notion that the myoepithelial cells of IDC are non-neoplastic. Five IDCs with known RET fusions by RNA sequencing were retrieved from the authors’ archives, including 4 intercalated duct-like IDCs with NCOA4-RET, and 1 mixed intercalated duct-like/apocrine IDC with TRIM27-RET. A panel of immunohistochemistry antibodies (S100 protein, p63 or p40, mammaglobin, smooth muscle actin, calponin, androgen receptor) was tested. To precisely localize RET split-positive cells, each case was subjected to sequential retrieval of whole-slide imaging data of hematoxylin and eosin (HE) staining, immunofluorescence staining for calponin, and fluorescence in situ hybridization (FISH) for RET. Because NCOA4-RET is an inversion difficult to visualize on conventional RET FISH, a novel 3-color FISH technique was utilized to demonstrate it clearly. In all 5 cases, the proliferative ducts were completely surrounded by a layer of myoepithelial cells that were positive for p63 or p40, smooth muscle actin, and calponin. Using combined HE, calponin immunofluorescence, and RET FISH imaging, the positive signals were unmistakably identified in both calponin-negative ductal cells and peripheral, calponin-positive myoepithelial cells in all 5 cases. Utilizing combined HE, calponin immunofluorescence, and RET FISH imaging, we demonstrated that IDCs with RET fusions harbored this alteration in both the ductal and myoepithelial cells. This is compelling evidence that the myoepithelial cells of IDC are not mere bystanders, but are rather a component of the neoplasm itself, similar to other biphasic salivary gland neoplasms like pleomorphic adenoma and epithelial-myoepithelial carcinoma. This finding raises questions about the appropriate terminology, classification, and staging of IDC.
PubMed ID: 33086236
Article Size: <1 MB

Salivary Intraductal Carcinoma Arising within Intraparotid Lymph Node: A Report of 4 Cases with Identification of a Novel STRN-ALK Fusion

Rooper LM, Thompson LDR, Gagan J, Oliai BR, Weinreb I, Bishop JA.
Head Neck Pathol. 2021 Mar;15(1):179-185. doi: 10.1007/s12105-020-01198-0. Epub 2020 Jul 13.
Intraductal carcinoma (IDC) is a rare salivary gland tumor that is considered analogous to ductal carcinoma in-situ of the breast, demonstrating a complex neoplastic epithelial proliferation surrounded by a continuous layer of presumed non-neoplastic myoepithelial cells. It is subcategorized into intercalated duct, apocrine, and hybrid subtypes based on morphologic and immunohistochemical features, with frequent NCOA4-RET and TRIM27-RET fusions, respectively, seen in intercalated duct and hybrid tumors. However, as an expanding clinicopathologic spectrum of IDC has been documented, controversy has emerged as to whether this tumor type is best defined by its intraductal growth pattern or distinctive molecular and immunophenotypic differentiation. Here, we further explore the nature of IDC by evaluating four cases that arose within intraparotid lymph nodes. These intercalated-duct phenotype tumors with diffuse S100 protein expression demonstrated a crowded and complex epithelial proliferation arranged in cystic, cribriform, and micropapillary architecture, surrounded by an intact myoepithelial cell layer, and were completely intranodal. Of two tumors with tissue available for molecular analysis, one demonstrated a NCOA4-RET fusion and one harbored a STRN-ALK fusion that is novel to IDC. Not only does the intranodal presence of IDC present a challenging differential diagnosis, but the complex nature of this proliferation within lymph node tissue raises questions as to whether the myoepithelial component of IDC is actually non-neoplastic in nature. Furthermore, identification of a STRN-ALK fusion expands the genetic spectrum of IDC and adds to evidence of an emerging role for ALK in salivary gland tumors. Further attention to the nature of the myoepithelial cells and documentation of alternate fusion events in IDC may inform continued discussion about its appropriate classification.
PubMed ID: 32661669
Article Size: 2.2 MB

Don’t stop the champions of research now: a brief history of head and neck pathology developments.

Thompson LDR, Lewis JS Jr, Skálová A, Bishop JA.
Hum Pathol. 2020 Jan;95:1-23. doi: 10.1016/j.humpath.2019.08.017. Epub 2019 Aug 23.
The field of Head and Neck Pathology was just developing 50years ago, but has certainly come a long way in a relatively short time. Thousands of developments in diagnostic criteria, tumor classification, malignancy staging, immunohistochemistry application and molecular testing have been made during this time, with an exponential increase in literature on the topics over the past few decades: There were 3506 articles published on head and neck topics in the decade between 1969 and 1978 (PubMed source), with a staggering 89266 manuscripts published in the most recent decade. It is daunting and impossible to narrow the more than 162000 publications in this field and suggest only a few topics of significance. However, the breakthru in this anatomic discipline has been achieved in three major sites: oropharyngeal carcinoma, salivary gland neoplasms, and sinonasal tract tumors. This review will highlight selected topics in these anatomic sites in which the most profound changes in diagnosis have occurred, focusing on the information that helps to guide daily routine practice of surgical pathology.
PubMed ID: 31449826
Article Size: 9.5 MB

Salivary Duct Carcinoma: The Predominance of Apocrine Morphology, Prevalence of Histologic Variants, and Androgen Receptor Expression

Williams L, Thompson LD, Seethala RR, Weinreb I, Assaad AM, Tuluc M, Ud Din N, Purgina B, Lai C, Griffith CC, Chiosea SI.
Am J Surg Pathol. 2015 May;39(5):705-13.
Salivary duct carcinoma (SDC) is a prototypic aggressive salivary gland carcinoma. Our aim is to determine the prevalence of histologic variants (micropapillary, basal-like) and androgen receptor (AR) expression in a large multi-institutional series of SDC. AR status was determined by immunohistochemistry (IHC). Most SDCs were characterized by an apocrine phenotype and AR expression. Cases with a nonapocrine phenotype and AR-negative status were studied by additional IHC and fluorescence in situ hybridization for ETV6 or MYB/NFIB. The diagnosis of SDC was confirmed in 187 of 199 (94%) cases. Variant morphologies were identified in 12 cases: micropapillary (n=6), sarcomatoid (n=3), mucinous (n=2), and basal-like (n=1). AR IHC was performed in 183 cases, of which 179 (97.8%) showed AR expression. On the basis of morphologic appearance and results of additional studies, 12 cases were reclassified as squamous cell carcinoma (SCC) (n=4), epithelial-myoepithelial carcinoma with high-grade transformation (HGT) (n=2), myoepithelial carcinoma (n=2), mammary analogue secretory carcinoma, high grade (ETV6 translocated; n=1), adenoid cystic carcinoma with HGT (n=1), acinic cell carcinoma with HGT (n=1), and adenosquamous carcinoma (n=1). AR-negative SDC is extremely rare, and the majority of such cases are more accurately classified as other entities. HGTs of other salivary carcinomas and squamous cell carcinoma are the most common mimics of SDC. SDCs with variant morphologies still show at least a minor component of conventional apocrine appearance. Thus, apocrine morphology defines SDC.
PubMed ID: 25871467
Article Size: 1 MB
 
 
 
 

Salivary duct carcinoma and the concept of early carcinoma ex pleomorphic adenoma

Griffith CC, Thompson LD, Assaad A, Purgina BM, Lai C, Bauman JE, Weinreb I, Seethala RR, Chiosea SI.
Histopathology. 2014 Dec;65(6):854-60.
AIMS: The data on the histological type of carcinomatous component and the extent of extracapsular invasion for salivary carcinomas ex pleomorphic adenoma (PA) are conflicting. We aimed to determine the prognostic value of extracapsular invasion in salivary duct carcinomas (SDC) ex PA.
METHODS AND RESULTS: A total of 117 patients with SDC were identified retrospectively; 44 cases involving major salivary glands had pre-existing PA (44 of 117, 37%). The morphological spectrum of SDC ex PA was characterized. The primary endpoint was overall survival (OS). Most SDC ex PA were widely invasive at presentation (27 of 44; 61%). Five patients with intracapsular SDC ex PA experienced no disease progression. The assessment of extracapsular invasion was precluded in eight cases (e.g. positive margins of resection). The rate of lymph node involvement was similar in cases with extracapsular invasion of ?2 mm (two of three) and >7 mm (22 of 26). Only pT correlated with OS [116 months, 95% confidence interval (CI) 22-210 months for pT1 versus 20 months (95% CI 6-34) for pT4; P = 0.013].
CONCLUSIONS: Intracapsular SDC ex PA are potentially indolent. SDC ex PA with extracapsular invasion of ?2 mm are rare, and appear to be clinically aggressive. Several histological parameters preclude assessment of extracapsular invasion.
PubMed ID: 24804831
Article Size: <1 MB
 
 
 
 

Recurrent IDH2 Mutations in Salivary Gland Striated Duct Adenoma Define an Expanded Histologic Spectrum Distinct From Canalicular Adenoma

Rooper LM, Agaimy A, Assaad A, Bal M, Eugene H, Gagan J, Nonogaki H, Palsgrove DN, Shah A, Stelow E, Stoehr R, Thompson LDR, Weinreb I, Bishop JA.
Am J Surg Pathol. 2023 Mar 1;47(3):333-343.
Striated duct adenoma (SDA) is a rare salivary gland neoplasm defined by histologic similarity to normal striated ducts. However, doubt persists about whether SDA represents a genuine entity distinct from canalicular adenoma and if a malignant counterpart exists. This study aims to evaluate the molecular underpinnings of SDA to clarify its pathogenesis and classification. We identified 10 SDA and 2 tumors called low-grade adenocarcinoma not otherwise specified that were retrospectively recognized to resemble SDA. All cases showed recurrent histologic features including (1) discrete monophasic tubules, (2) tall columnar eosinophilic cells, (3) monotonous oval nuclei, and (4) scant fibrous stroma, and most were positive for S100 protein (91%), SOX10 (80%), and CK7 (80%). Although 1 case was previously called adenocarcinoma based on interdigitation with normal acini, this pattern was also seen in some SDA, and likely does not indicate malignancy; the significance of growth surrounding nerve in 1 other case is less clear. Targeted sequencing identified IDH2 R172X mutations in all 8 cases with sufficient tissue, with positivity for IDH1/2 mutation-specific immunohistochemistry in 9 cases stained. In contrast, 5 canalicular adenomas lacked IDH2 mutations or other oncogenic alterations. Overall, IDH2 R172X mutations are a defining feature of SDA that, in combination with its recognizable pathologic profile, confirm it is a unique entity separate from canalicular adenoma. IDH1/2 mutation-specific immunohistochemistry may provide a convenient tool to facilitate diagnosis. Both morphology and IDH2 mutations raise parallels between SDA and breast tall cell carcinoma with reverse polarity.
PubMed ID: 36510691
Article Size: 2.14 MB

Subsets of Salivary Duct Carcinoma Defined by Morphologic Evidence of Pleomorphic Adenoma, PLAG1 or HMGA2 Rearrangements, and Common Genetic Alterations

Chiosea SI, Thompson LD, Weinreb I, Bauman JE, Mahaffey AM, Miller C, Ferris RL, Gooding WE.
Cancer. 2016 Oct 15;122(20):3136-3144. doi: 10.1002/cncr.30179. Epub 2016 Jul 5.
BACKGROUND: The authors hypothesized that histogenetic classification of salivary duct carcinoma (SDC) could account for de novo tumors and those with morphologic or molecular evidence (pleomorphic adenoma gene 1 [PLAG1], high-mobility group AT hook 2 [HMGA2] rearrangement, amplification) of pleomorphic adenoma (PA).
METHODS: SDCs (n = 66) were reviewed for morphologic evidence of PA. PLAG1 and HMGA2 alterations were detected by fluorescence in situ hybridization (FISH). PLAG1-positive tumors were tested by FISH for fibroblast growth factor receptor 1 (FGFR1) rearrangement. Thirty-nine tumors were analyzed using a commercial panel for mutations and copy number variations in 50 cancer-related genes.
RESULTS: On the basis of combined morphologic and molecular evidence of PA, 4 subsets of SDC emerged: 1) carcinomas with morphologic evidence of PA but intact PLAG1 and HMGA2 (n = 22); 2) carcinomas with PLAG1 alteration (n = 18) or 3) HMGA2 alteration (n = 12); and 4) de novo carcinomas, without morphologic or molecular evidence of PA (n = 14). The median disease-free survival was 37 months (95% confidence interval, 28.4-45.6 months). Disease-free survival and other clinicopathologic parameters did not differ for the subsets defined above. Combined Harvey rat sarcoma viral oncogene homolog/phosphatidylinositol-4,5-biphosphate 3-kinase, catalytic subunit α (HRAS/PIK3CA) mutations were observed predominantly in de novo carcinomas (5 of 8 vs 2 of 31 tumors; P = .035). Erb-B2 receptor tyrosine kinase 2 (ERBB2) copy number gain was not observed in de novo carcinomas (0 of 8 vs 12 of 31 tumors; P = .08). Tumor protein 53 (TP53) mutations were more common in SDC ex pleomorphic adenomas than in de novo carcinomas (17 of 31 vs 1 of 8 tumors; P = .033).
CONCLUSIONS: The genetic profile of SDC varies with the absence or presence of pre-existing PA and its cytogenetic signature. Most de novo SDCs harbor combined HRAS/PIK3CA mutations and no ERBB2 amplification.
PubMed ID: 27379604
Article Size: <1 MB
 
 
 
 

A Subset of Salivary Intercalated Duct Lesions Harbors Recurrent CTNNB1 and HRAS Mutations: A Molecular Link to Basal Cell Adenoma and Epithelial-Myoepithelial Carcinoma?

McLean AC, Rooper LM, Gagan J, Thompson LDR, Bishop JA.
Head Neck Pathol. 2023 Jun;17(2):393-400. doi: 10.1007/s12105-022-01513-x.
BACKGROUND: Intercalated duct lesions (IDLs) are benign salivary gland proliferations that resemble normal intercalated ducts and are subdivided into hyperplastic, adenoma or hybrid types depending on circumscription. While IDLs were historically regarded as non-neoplastic, frequent association with basal cell adenoma (BCA) and epithelial-myoepithelial carcinoma (EMC) has raised the possibility that they are neoplastic precursors.
METHODS: In this study, we performed β-catenin immunohistochemistry and targeted molecular analysis on IDLs to clarify their pathogenesis.
RESULTS: We identified 15 IDLs from the parotid glands of eight men and six women with a median age of 65 years (range 42-85 years). These lesions included nine hyperplastic, three adenoma, and three hybrid types. Nuclear β-catenin localization was present in 7 of 13 lesions tested (54%). Next generation sequencing was successfully completed in 12 IDLs, of which seven (58%) had likely oncogenic mutations. These included three recurrent CTNNB1 mutations in hyperplastic (n = 2) and hybrid (n = 1) lesions and two recurrent HRAS hotspot mutations in adenomas.
CONCLUSION: Despite substantial heterogeneity, these findings confirm that a majority of IDLs are genuinely neoplastic, and some demonstrate molecular overlap with both BCA and EMC, supporting their theorized role as precursors to these tumors. Nevertheless, no oncogenic drivers were present in a significant subset of cases, suggesting that some IDLs may be truly reactive and hyperplastic. As such, IDL appear to represent a diverse morphologic and molecular spectrum that include both neoplastic and hyperplastic lesions. Reconsideration of the boundary between IDL and BCA in the future may be necessary to simplify classification.
PubMed ID: 36480093
Article Size: 2 MB

Definitive treatment of androgen receptor–positive salivary duct carcinoma with androgen deprivation therapy and external beam radiotherapy.

Soper MS, Iganej S, Thompson LD.
Head Neck. 2014 Jan;36(1):E4-7.
BACKGROUND: Salivary duct carcinoma (SDC) is an aggressive malignancy with high recurrence rates. Standard management includes surgical resection followed by adjuvant radiation. Androgen receptor positivity has been described to be present in 40% to 90% of SDCs, and a recent case series showed a benefit to androgen deprivation therapy (ADT) in recurrent or metastatic disease.
METHODS AND RESULTS: We present the case of an 87-year-old woman with a locally advanced androgen receptor-positive parotid SDC treated definitively with ADT and external beam radiotherapy, a regimen modeled after the treatment of prostate cancer. She had a complete response on positron emission tomography (PET)/CT scan and had no evidence of disease 24 months after the completion of treatment.
CONCLUSION: To our knowledge, this case report is the first to describe the use of ADT plus radiation to definitively treat SDC. This regimen could be considered in patients with androgen receptor-positive SDCs who are considered unresectable or who refuse surgery.
PubMed ID: 23720164
Article Size: <1 MB
 

Epithelial-Myoepithelial Carcinoma: Frequent Morphologic and Molecular Evidence of Preexisting Pleomorphic Adenoma, Common HRAS Mutations in PLAG1-intact and HMGA2-intact Cases, and Occasional TP53, FBXW7, and SMARCB1 Alterations in High-grade Cases.

El Hallani S, Udager AM, Bell D, Fonseca I, Thompson LDR, Assaad A, Agaimy A, Luvison AM, Miller C, Seethala RR, Chiosea S.
Am J Surg Pathol. 2018 Jan;42(1):18-27.
We hypothesized that there is a relationship between the preexisting pleomorphic adenoma [PA]), histologic grade of epithelial-myoepithelial carcinomas (EMCAs), and genetic alterations. EMCAs (n=39) were analyzed for morphologic and molecular evidence of preexisting PA (PLAG1, HMGA2 status by fluorescence in situ hybridization, FISH, and FGFR1-PLAG1 fusion by next-generation sequencing, NGS). Twenty-three EMCAs were further analyzed by NGS for mutations and copy number variation in 50 cancer-related genes. On the basis of combined morphologic and molecular evidence of PA, the following subsets of EMCA emerged: (a) EMCAs with morphologic evidence of preexisting PA, but intact PLAG1 and HMGA2 (12/39, 31%), (b) Carcinomas with PLAG1 alterations (9/39, 23%), or (c) HMGA2 alterations (10/39, 26%), and (d) de novo carcinomas, without morphologic or molecular evidence of PA (8/39, 21%). Twelve high-grade EMCAs (12/39, 31%) occurred across all subsets. The median disease-free survival was 80 months (95% confidence interval, 77-84 mo). Disease-free survival and other clinicopathologic parameters did not differ by the above defined subsets. HRAS mutations were more common in EMCAs with intact PLAG1 and HMGA2 (7/9 vs. 1/14, P<0.001). Other genetic abnormalities (TP53 [n=2], FBXW7 [n=1], SMARCB1 deletion [n=1]) were seen only in high-grade EMCAs with intact PLAG1 and HMGA2. We conclude that most EMCAs arose ex PA (31/39, 80%) and the genetic profile of EMCA varies with the absence or presence of preexisting PA and its cytogenetic signature. Progression to higher grade EMCA with intact PLAG1 and HMGA2 correlates with the presence of TP53, FBXW7 mutations, or SMARCB1 deletion.
PubMed ID: 29135520
Article Size: 1.2 MB
 

Histologic Classification and Molecular Signature of Polymorphous Adenocarcinoma (PAC) and Cribriform Adenocarcinoma of Salivary Gland (CASG): An International Interobserver Study.

Xu B, Barbieri AL, Bishop JA, Chiosea SI, Dogan S, Di Palma S, Faquin WC, Ghossein R, Hyrcza M, Jo VY, Lewis JS Jr, Lozada JR, Michal M, Pareja FG, Perez-Ordonez B, Prasad ML, Purgina B, Reis-Filho JS, Scognamiglio T, Sebastiao APM, Seethala RR, Skálová A, Smith SM, Tekkeşin MS, Thompson LDR, Wasseman JK, Wenig BM, Weinreb I, Katabi N.
Am J Surg Pathol. 2020 Apr;44(4):545-552. doi: 10.1097/PAS.0000000000001431.
Polymorphous adenocarcinoma (PAC) shows histologic diversity with streaming and targetoid features whereas cribriform adenocarcinoma of salivary gland (CASG) demonstrates predominantly cribriform and solid patterns with glomeruloid structures and optically clear nuclei. Opinions diverge on whether CASG represents a separate entity or a variant of PAC. We aimed to assess the level of agreement among 25 expert Head and Neck pathologists in classifying these tumors. Digital slides of 48 cases were reviewed and classified as: PAC, CASG, tumors with ≥50% of papillary architecture (PAP), and tumors with indeterminate features (IND). The consensus diagnoses were correlated with a previously reported molecular alteration. The consensus diagnoses were PAC in 18/48, CASG in16/48, PAP in 3/48, and IND in 11/48. There was a fair interobserver agreement in classifying the tumors (κ=0.370). The full consensus was achieved in 3 (6%) cases, all of which were classified as PAC. A moderate agreement was reached for PAC (κ=0.504) and PAP (κ=0.561), and a fair agreement was reached for CASG (κ=0.390). IND had only slight diagnostic concordance (κ=0.091). PAC predominantly harbored PRKD1 hotspot mutation, whereas CASG was associated with fusion involving PRKD1, PRKD2, or PRKD3. However, such molecular events were not exclusive as 7% of PAC had fusion and 13% of CASG had mutation. In conclusion, a fair to moderate interobserver agreement can be achieved in classifying PAC and CASG. However, a subset (23%) showed indeterminate features and was difficult to place along the morphologic spectrum of PAC/CASG among expert pathologists. This may explain the controversy in classifying these tumors.
PubMed ID: 31917707
Article Size: <1 MB

Metastatic cutaneous squamous cell carcinoma accounts for nearly all squamous cell carcinomas of the parotid gland

Bradley PJ, Stenman G, Thompson LDR, Skálová A, Simpson RHW, Slootweg PJ, Franchi A, Zidar N, Nadal A, Hellquist H, Williams MD, Leivo I, Agaimy A, Ferlito A.
Virchows Arch. 2024 Apr 17. doi: 10.1007/s00428-024-03798-5. Online ahead of print.
Primary squamous cell carcinoma of the parotid gland (pSCCP) has long been recognized as a separate entity and is included in the WHO classifications of salivary gland tumors. However, it is widely accepted among head and neck pathologists that pSCCP is exceptionally rare. Yet, there are many publications describing series of pSCCP and data from SEER and other cancer register databases indicate erroneously an increasing incidence of pSCCP. Importantly, pSCCP and metastatic (secondary) squamous cell carcinoma to the parotid gland (mSCCP) have nearly identical histological features, and the diagnosis of pSCCP should only be made after the exclusion of mSCCP. Moreover, all of the histological diagnostic criteria proposed to be in favor of pSCCP (such as, for example, dysplasia of ductal epithelium) can be encountered in unequivocal mSCCP, thereby representing secondary growth along preexistent ducts. Squamous cell differentiation has also been reported in rare genetically defined primary parotid carcinomas, either as unequivocal histological squamous features (e.g., NUT carcinoma, mucoepidermoid carcinoma), by immunohistochemistry (e.g., in NUT carcinoma, adamantinoma-like Ewing sarcoma, basal-type salivary duct carcinoma, mucoepidermoid carcinoma), or a combination of both. Another major issue in this context is that the International Classification of Diseases (ICD) coding system does not distinguish between primary or metastatic disease, resulting in a large number of patients with mSCCP being misclassified as pSCCP. Immunohistochemistry and new molecular biomarkers have significantly improved the accuracy of the diagnosis of many salivary gland neoplasms, but until recently there were no biomarkers that can accurately distinguish between mSCCP and pSCCP. However, recent genomic profiling studies have unequivocally demonstrated that almost all SCCP analyzed to date have an ultraviolet light (UV)-induced mutational signature typical of mSCCP of skin origin. Thus, mutational signature analysis can be a very useful tool in determining the cutaneous origin of these tumors. Additional molecular studies may shed new light on this old diagnostic and clinical problem. This review presents a critical view of head and neck experts on this topic.
PubMed ID: 38630141
Article Size: 2 MB

Salivary duct carcinoma.

Thompson LD.
Ear Nose Throat J. 2012 Sep;91(9):356-9.
FIRST PARAGRAPH: Salivary duct carcinoma is a high-grade adenocarcinoma that resembles breast ductal carcinoma. It is believed to be derived from intra- and interlobular excretory ducts. Salivary duct carcinoma may arise de novo or as a relatively common malignant component of a carcinoma ex pleomorphic adenoma. It accounts for about 9% of all malignant salivary gland tumors. Although there is a wide age range at presentation, most patients present in the seventh decade of life; men are affected much more frequently than women (4:1).
PubMed ID: 22996706
Article Size: <1 MB

Secretory carcinoma.

Thompson LD.
Ear Nose Throat J. 2016 Dec;95(12):474-476.
FIRST PARAGRAPH: Secretory carcinoma, first described as mammary analogue secretory carcinoma (MASC), is a recently described, distinctive malignant salivary gland tumor that is quite similar to secretory breast carcinoma, defined by the t(12;15)(p13;q25) translocation resulting in an ETV6-NTRK3 fusion product. The vast majority of these tumors used to be included in the acinic cell carcinoma category.
PubMed ID: 27929593
Article Size: <1 MB

Polymorphous low grade adenocarcinoma: a clinicopathologic study of 164 cases.

Castle JT, Thompson LD, Frommelt RA, Wenig BM, Kessler HP.
Cancer. 1999 Jul 15;86(2):207-19.
BACKGROUND: Polymorphous low grade adenocarcinomas (PLGA) are minor salivary gland neoplasms with a predilection for intraoral sites.
METHODS: One hundred sixty-four cases of PLGA diagnosed between 1970-1994 were retrieved from the files of the Armed Forces Institute of Pathology, Washington, DC. Histologic features were reviewed, immunohistochemical studies and prognostic markers were performed, and patient follow-up was obtained. The data were analyzed statistically.
RESULTS: The patients included 109 women and 55 men, ages 23-94 years (average, 57.6 years). The patients usually presented clinically with a palatal mass that ranged in size from 0.4-6 cm (average, 2.2 cm). The tumors were infiltrative and characterized by a polymorphous growth pattern, with individual tumors demonstrating multiple patterns, including solid, ductotubular, cribriform, trabecular, and single file growth. Neurotropism was identified frequently. The neoplastic cells were isomorphic with vesicular nuclei. Mitotic activity was inconspicuous. At an average of 115.4 months after presentation, approximately 97.6% of all patients were either alive or had died without evidence of recurrent disease after treatment with surgical excision only. Four patients had evidence of disease at last follow-up; three had died with evidence of tumor, and one patient was alive with tumor.
CONCLUSIONS: PLGA is a neoplasm of minor salivary gland origin that must be separated from adenoid cystic carcinoma and benign mixed tumor for therapeutic and prognostic considerations. Conservative but complete surgical excision is the treatment of choice for these slow-growing tumors with a low proliferation index; adjuvant therapy does not appear to alter the prognosis.
PubMed ID: 10421256
Article Size: 2 MB
 

Novel PRKD Gene Rearrangements and Variant Fusions in Cribriform Adenocarcinoma of Salivary Gland Origin

Weinreb I, Zhang L, Tirunagari LM, Sung YS, Chen CL, Perez-Ordonez B, Clarke BA, Skalova A, Chiosea SI, Seethala RR, Waggott D, Boutros PC, How C, Liu FF, Irish JC, Goldstein DP, Gilbert R, Ud Din N, Assaad A, Hornick JL, Thompson LD, Antonescu CR.
Genes Chromosomes Cancer. 2014 Oct;53(10):845-56.
Polymorphous low-grade adenocarcinoma (PLGA) and cribriform adenocarcinoma of minor salivary gland (CAMSG) are low-grade carcinomas arising most often in oral cavity and oropharynx, respectively. Controversy exists as to whether these tumors represent separate entities or variants of one spectrum, as they appear to have significant overlap, but also clinicopathologic differences. As many salivary carcinomas harbor recurrent translocations, paired-end RNA sequencing and FusionSeq data analysis was applied for novel fusion discovery on two CAMSGs and two PLGAs. Validated rearrangements were then screened by fluorescence in situ hybridization (FISH) in 60 cases. Histologic classification was performed without knowledge of fusion status and included: 21 CAMSG, 18 classic PLGA, and 21 with ‘mixed/indeterminate’ features. The RNAseq of 2 CAMSGs showed ARID1A-PRKD1 and DDX3X-PRKD1 fusions, respectively, while no fusion candidates were identified in two PLGAs. FISH for PRKD1 rearrangements identified 11 additional cases (22%), two more showing ARID1A-PRKD1 fusions. As PRKD2 and PRKD3 share similar functions with PRKD1 in the diacylglycerol and protein kinase C signal transduction pathway, we expanded the investigation for these genes by FISH. Six additional cases each showed PRKD2 and PRKD3 rearrangements. Of the 26 (43%) fusion-positive tumors, there were 16 (80%) CAMSGs and 9 (45%) indeterminate cases. A PRKD2 rearrangement was detected in one PLGA (6%). We describe novel and recurrent gene rearrangements in PRKD1-3 primarily in CAMSG, suggesting a possible pathogenetic dichotomy from ‘classic’ PLGA. However, the presence of similar genetic findings in half of the indeterminate cases and a single PLGA suggests a possible shared pathogenesis for these tumor types.
PubMed ID: 24942367
Article Size: <1 MB
 
 
 
 

Hotspot activating PRKD1 somatic mutations in polymorphous low-grade adenocarcinomas of the salivary glands

Weinreb I, Piscuoglio S, Martelotto LG, Waggott D, Ng CK, Perez-Ordonez B, Harding NJ, Alfaro J, Chu KC, Viale A, Fusco N, da Cruz Paula A, Marchio C, Sakr RA, Lim R, Thompson LD, Chiosea SI, Seethala RR, Skalova A, Stelow EB, Fonseca I, Assaad A, How C, Wang J, de Borja R, Chan-Seng-Yue M, Howlett CJ, Nichols AC, Wen YH, Katabi N, Buchner N, Mullen L, Kislinger T, Wouters BG, Liu FF, Norton L, McPherson JD, Rubin BP, Clarke BA, Weigelt B, Boutros PC, Reis-Filho JS.
Nat Genet. 2014;Nov;(46(11):1166-9.
Polymorphous low-grade adenocarcinoma (PLGA) is the second most frequent type of malignant tumor of the minor salivary glands. We identified PRKD1 hotspot mutations encoding p.Glu710Asp in 72.9% of PLGAs but not in other salivary gland tumors. Functional studies demonstrated that this kinase-activating alteration likely constitutes a driver of PLGA.
PubMed ID: 25240283
Article Size: 1 MB
 
 
 
 

Polymorphous low grade adenocarcinoma.

Thompson LDR.
Pathol Case Rev 2004;9:259-263.
Polymorphous low-grade adenocarcinomas are minor salivary gland neoplasms with a predilection for intraoral sites. Women are affected twice as frequently as men, and generally present in the fifth to sixth decade of life with a painless ihaoral mass. The palatal mass is, on average, about 2 cm in greatest dimension. The tumors are submucosal, identified below an intact mucosa as a well-circumscribed although unencapsulated mass. The tumor is characterized by a polymorphous growth pattern, with individual tumors demonstrating multiple patterns, including solid, ductal-tubular, cribriform, trabecular, and single-file growth. Neurotropism is common, frequently forming a central nidus around which a “targetoid” pattern is formed. The neoplastic cells are isomorphic, containing round to oval vesicular nuclei with small nucleoli. Mitotic activity and necrosis are inconspicuous. There is frequently a slate gray-blue stroma separating the tumor cells. Immunohistochemical analysis demonstrates reactivity with cytokeratin, vimentin, S-100 protein, CD117, glial fibrillary acidic protein, and actin. Bcl-2 is overexpressed and there is generally a low proliferation index as determined by Ki-67 reactions. The tumor must be separated from pleomorphic adenoma (benign mixed tumor) and adenoid cystic carcinoma. Complete surgical excision will yield a more than 95% 10-year survival, although persistence or recurrence can emerge often in about 10% of patients more than 10 years later.
PubMed ID: n/a
Article Size: 4.9 MB

Mucoepidermoid Carcinoma May Be Devoid of Squamoid Cells by Immunohistochemistry: Expanding the Histologic and Immunohistochemical Spectrum of MAML2- Rearranged Salivary Gland Tumors

Bishop JA, Thompson LDR, Siegele B, Gagan J, Mansour M, Chernock RD, Rooper LM.
Histopathology. 2023 Jan;82(2):305-313. doi: 10.1111/his.14817.
Mucoepidermoid carcinoma (MEC) is historically defined by a mix of squamoid, intermediate, and mucous cells, but we have recently encountered several cases lacking immunoreactivity for squamous markers p40, p63, and CK5/6 despite MAML2 fusions. This study will characterise these unique tumours. Ten MEC were collected arising from the parotid gland (n = 4), submandibular gland (n = 2), nasopharynx (n = 1), base of tongue (n = 1), bronchus (n = 1), and trachea (n = 1). Six tumours were low-grade, two intermediate-grade, one high-grade, and one demonstrated low-grade areas with high-grade transformation. Four cases were oncocytic, four had clear-cell features, two had spindle cell features, and one high-grade MEC had prominent solid, cord-like, and micropapillary features. The tumours were negative for p40 (10/10), p63 (10/10), and CK5/6 (9/9). Targeted RNA sequencing demonstrated CRTC1::MAML2 in five cases, CRTC3::MAML2 in two, and a novel MAML2::CEP126 in the unusual high-grade case. In two cases with insufficient RNA, MAML2 fluorescence in situ hybridisation (FISH) showed rearrangement. Genetically-confirmed MEC may lack overt squamous differentiation by histology and immunohistochemistry. While most cases harboured canonical fusions and fit within the spectra of MEC variants with oncocytic, clear cell, and/or spindle cell features, one had a novel MAML2::CEP126 fusion and unusual morphology. In MEC without squamoid cells, the use of immunohistochemistry may hinder, rather than aid, the correct diagnosis. In such cases, MAML2 analysis is most useful. The historical definition of MEC as a carcinoma with squamoid, intermediate and mucous cells should be revisited.
PubMed ID: 36208053
Article Size: 2.7 MB

Canalicular Adenoma: A Clinicopathologic and Immunohistochemical Analysis of 67 Cases with a Review of the Literature

Thompson LD, Bauer JL, Chiosea S, McHugh JB, Seethala RR, Miettinen M, Müller S.
Head Neck Pathol. 2015 Jun;9(2):181-95.
There is a lack of a comprehensive immunohistochemical (IHC) analysis of canalicular adenoma (CanAd), especially when combined with a description of the unique histologic features. Given the usual small biopsies, IHC may be useful in distinguishing CanAd from other tumors in the differential diagnosis. Retrospective. The patients included 54 females and 13 males (4.2:1), aged 43-90 years, with a mean age at presentation of 69.9 years. Clinical presentation was generally a mass (n = 61) slowly increasing in size (mean 38.5 months), affecting the upper lip (n = 46), buccal mucosa (n = 17) or palate (n = 4), involving the right (n = 29), left (n = 24) or midline (n = 9), without any major salivary gland tumors. The tumors ranged in size from 0.2 to 3 cm (mean 1.2 cm). Most tumors were multilobular or bosselated (76 %), often surrounded by a capsule. Histologically, the tumors were characterized by cystic spaces, tumor cords with beading, tubule formation, and by the presence of luminal squamous balls (n = 41). The cells were cuboidal to columnar with stippled chromatin. Mitoses were inconspicuous. A myxoid stroma (n = 64), sclerosis (n = 42), luminal hemorrhage (n = 51), and luminal microliths (calcifications) (n = 33) were characteristic. Nine (13.4 %) were multifocal. CanAd showed the following characteristic immunohistochemistry findings: CK-pan and S100 protein (strong, diffuse reaction); peripheral or luminal GFAP reaction; CK5/6 and p16 luminal squamous ball reaction; SOX10 nuclear reaction; cytoplasmic p63 reaction. CanAd are unique minor salivary gland tumors showing a distinct architecture and phenotype. They predilect to older women, with the majority multilobulated and affecting the upper lip, multifocal in 13 %; no major salivary gland tumors were identified. S100 protein, CK-pan, GFAP and SOX10 are positive, with luminal squamous balls highlighted by CK5/6 or p16.
PubMed ID: 25141970
Article Size: 4.5 MB
 
 
 
 

Canalicular adenoma.

Penner CR, Thompson L.
Ear Nose Throat J. 2005 Mar;84(3):132.
FIRST PARAGRAPH: Canalicular adenomas are benign neoplasms with a unique predilection for the upper lip (~80% of cases). They account for 1% of all salivary gland neoplasms. Their incidence peaks during the seventh decade of life; they are distinctly uncommon in patients younger than 50 years of age. The female-to-male predominance is approximately 2:1.
PubMed ID: 15871577
Article Size: <1 MB

Lymphoepithelial Carcinoma of Salivary Glands.

Thompson LDR, Whaley RD.
Surg Pathol Clin. 2021 Mar;14(1):75-96. doi: 10.1016/j.path.2020.09.009.
Lymphoepithelial carcinoma of salivary glands (LECSG) is an uncommon neoplasm. This article summarizes the findings of 438 cases in a review of the literature. Concurrent lymphoepithelial lesions may suggest a primary tumor. The tumor shows a nonkeratinizing carcinoma intimately associated with a rich lymphohistiocytic infiltrate, destroying adjacent salivary gland tissue. Irrespective of race or ethnicity, the tumors usually express Epstein-Barr virus, with Epstein-Barr virus encoded small RNA (EBER) and/or latent membrane protein-1 (LMP-1), although a subset does not. There is an overall good prognosis of about 80% at 5 years.
PubMed ID: 33526225
Article Size: 16.2 MB

Lymphoepithelial Carcinoma of Salivary Gland EBV‑association in Endemic versus Non‑Endemic Patients: A Report of 16 Cases

Whaley RD, Carlos R, Bishop JA, Rooper L, Thompson LDR.
Head Neck Pathol. 2020 Dec;14(4):1001-1012. doi: 10.1007/s12105-020-01172-w. Epub 2020 May 27.
Lymphoepithelial carcinoma of salivary glands (LECSG) are rare neoplasms, reported in endemic populations (southeastern Chinese) with a strong Epstein-Barr virus (EBV) association. A retrospective series comparing EBV status within an ethnically diverse population (endemic vs. non-endemic patients) has not been reported. Sixteen LECSG were equally distributed between males (n = 8) and females (n = 8) with a median age of 54 years (range 18 to 85 years) at initial diagnosis. Ten patients were white, 4 Asian, and 2 black. The patients typically presented with swelling or mass for an average of 11.6 months. Tumors affected only major salivary glands: parotid (n = 13); submandibular (n = 3). Tumors were an average of 2.9 cm (range 1.5 to 5.8 cm). Nine of 16 (56%) patients had cervical lymph node metastases at presentation. No patients had nasopharyngeal or oropharyngeal tumors. Microscopically, the tumors were widely infiltrative, characterized by large polygonal to spindled cells arranged in a syncytial, lattice-like network in a background of lymphoplasmacytic cells. The neoplastic cells showed an open-vesicular nuclear chromatin to a more basaloid-morphology, the latter showing hyperchromatic nuclei and less cytoplasm, while nearly all of the cases had associated lymphoepithelial lesions/sialadenitis. By in situ hybridization, 8 of 16 cases had a strong, diffuse EBER expression (4 of 4 Asians; 4 of 12 non-Asians), while with immunohistochemistry all cases tested were pan-cytokeratin, CK5/6 and p63 reactive; none of the cases tested were p16 reactive. All patients were managed with wide or radical excision, 4 with concurrent chemoradiation, and 6 with radiation alone. Distant metastasis (lung, brain, and bone) developed in 2 patients. Overall follow-up (mean 3.8 years) revealed 12 patients alive and 2 dead, none with evidence of disease (mean 4.3 years); one white male alive with disease at 1.9 years, and one Asian female dead of disease at 4.2 years; both of these latter patients had Group IV stage disease. High stage (Group IV) patients had a shorter mean survival than lower stage patients: 3.1 versus 4.8 years, respectively. In conclusion, LECSG are uncommon primary neoplasms. Concurrent lymphoepithelial lesions may help suggest a primary tumor. The tumors, irrespective of race or ethnicity, may express
PubMed ID: 32462279
Article Size: 3.6 MB

Lymphadenoma of the salivary gland: clinicopathological and immunohistochemical analysis of 33 tumors.

Seethala RR, Thompson LD, Gnepp DR, Barnes EL, Skalova A, Montone K, Kane S, Lewis JS Jr, Solomon LW, Simpson RH, Khan A, Prasad ML.
Mod Pathol. 2012 Jan;25(1):26-35.
Lymphadenomas (LADs) are rare salivary gland tumors. Their clinicopathologic characteristics and etiopathogenesis are poorly understood. We examined 33 LADs in 31 patients (17 women and 14 men) aged 11-79 years (median 65 years). There were 22 sebaceous LADs in 21 patients (9 women and 12 men) and 11 non-sebaceous LADs in 10 patients (8 women and 2 men). Two patients had synchronous double tumors. Twenty-six tumors (79%) arose in parotid, three in the neck, and two each in submandibular gland and oral cavity. Extraparotid tumors were seen in 2 of 21 (10%) patients with sebaceous and 4 of 10 (40%) patients with non-sebaceous LADs. Seven of twenty-three (30%) patients had immunosuppressive therapy for unrelated diseases. The tumors were well circumscribed, encapsulated (n=28, 84%) painless masses, varying in size from 0.6 to 6?cm (median 2.2). The cut surfaces were gray-tan to yellow, homogeneous and multicystic (n=24, 72%). The epithelial cells were basaloid, squamous and glandular, forming solid nests, cords, tubules, and cysts. Sebaceous differentiation was restricted to sebaceous lymphadenoma. The epithelial cells expressed basal cell markers (p63, 34BE12, and/or CK5/6, 18/18, 100%) and the luminal glandular cells expressed CK7 (12/12, 100%). Myoepithelial cells were absent (n=10/16, 63%) or focal. The lymphoid stroma was reactive, with germinal centers in 28 (84%). There was no evidence of HPV (0/11), EBV (0/7), and HHV-8 (0/8). Malignant transformation to sebaceous and basal cell adenocarcinoma was seen in one patient each. None of the 11 patients with follow-up (1-8 years) recurred. In summary, sebaceous and non-sebaceous LADs are benign, encapsulated, solid and cystic tumors affecting older adults. Non-sebaceous LADs affect women and extraparotid sites more frequently than sebaceous LADs. Altered immune status may have a role in their etiopathogenesis. Multiple synchronous tumors, origin in buccal mucosa, and malignant transformation may rarely occur.
PubMed ID: 21892186
Article Size: 1 MB
 

Diagnostic Approach to Fine Needle Aspirations of Cystic Lesions of the Salivary Gland

Pantanowitz L , Thompson LDR, Rossi ED.
Head Neck Pathol. 2018 Dec;12(4):548-561.
Fine needle aspiration (FNA) has diagnostic and therapeutic value in the management of salivary gland cysts. Rendering an accurate diagnosis from an aspirated salivary gland cyst is challenging because of the broad differential diagnosis, possibility of sampling error, frequent hypocellularity of specimens, morphologic heterogeneity, and overlapping cytomorphology of many cystic entities. To date, there have been no comprehensive review articles providing a practical diagnostic approach to FNA of cystic lesions of salivary glands. This article reviews the cytopathology of salivary gland cysts employing 2017 World Health Organization terminology, addresses the accuracy of FNA, and presents The Milan System approach for reporting in cystic salivary gland cases. The utility of separating FNA specimens from salivary gland cysts, based upon the presence of mucin and admixed lymphocytes in cyst fluid is demonstrated. A reliable approach to interpreting FNA specimens from patients with cystic salivary gland lesions is essential to accurately determine which of these patients may require subsequent surgery.
PubMed ID: 29524082
Article Size: 3.5 MB
 
 
 

Incisional or core biopsies of salivary gland tumours: how far should we go?

Nelson BL, Thompson LDR.
Diagnostic Pathology Volume 18:9 September 2012 pages 358-365.
Trends in the evaluation of salivary gland masses have changed as imaging studies have improved and sampling techniques have evolved over the past several decades. Whether clinically palpable or detected by imaging studies, salivary gland masses have been readily evaluated by fine needle aspiration. More recently, imaging guided core-needle biopsy has been employed with mixed results. The literature on these techniques is reviewed and analyzed with particular attention to tissue adequacy and diagnostic accuracy. Comparison is made using selected case presentations to highlight the advantages and disadvantages of establishing a diagnosis when core-needle biopsy is utilized. Core-needle biopsy of salivary gland tumours may be a useful first diagnostic approach as long as the limitations of the procedure are well understood and managed.
PubMed ID: n/a
Article Size: <1 MB

Outcome for Neoadjuvant Treatment of Parotid Gland Adamantinoma-Like Ewing Sarcoma: Case Report and Review of Literatures

Wei CH, Thompson LDR, Lee K, Chow W, Liang Y.
Int J Surg Pathol. 2022 Oct;30(7):776-783.
BACKGROUND: Adamantinoma-like Ewing sarcoma typically shows t(11;22) EWSR1::FLI1 translocation and complex epithelial differentiation. It poses a diagnostic challenge, especially in the head and neck region, due to its under-recognition and significant histologic overlap with other malignancies. Neoadjuvant and adjuvant treatment information on head and neck Adamantinoma-like Ewing sarcoma is limited.
CASE PRESENTATION: Herein, we report a case of a 78-year-old female with Adamantinoma-like Ewing sarcoma of the parotid gland, including the imaging findings and clinical response to neoadjuvant therapy followed by surgery. The efficacy of neoadjuvant therapy in the treatment of Adamantinoma-like Ewing sarcoma is discussed in the context of a review of pertinent literature.
CONCLUSION: Adamantinoma-like Ewing sarcoma in the head and neck is frequently misdiagnosed as poorly differentiated squamous cell carcinoma or a basaloid salivary gland carcinoma. Adamantinoma-like Ewing sarcoma is a EWS1::FLI1 translocation driven tumor; frequently misdiagnosed on head and neck biopsies as poorly differentiated carcinoma, or squamous cell carcinoma. Ewing sarcoma-specific chemoregimen appears effective for this entity. If diagnosed early, patient may be amenable to neoadjuvant therapy, which may improve surgical and cosmetic outcomes. This is especially important in head and neck regions.
PubMed ID: 35467446
Article Size: 1.9 MB

Evaluation of PAX2 and PAX8 Expression in Salivary Gland Neoplasms.

Butler RT, Alderman MA, Thompson LD, McHugh JB.
Head Neck Pathol. 2015 Mar;9(1):47-50.
PAX2 and PAX8 are transcription factors involved in embryogenesis that have been utilized as immunohistochemical indicators of tumor origin. Specifically, PAX2 is a marker of neoplasms of renal and müllerian origin, while PAX8 is expressed by renal, müllerian, and thyroid tumors. While studies examining these transcription factors in a variety of tumors have been published, data regarding their expression in salivary gland neoplasms are limited. The goal of this study was to assess expression of PAX2 and PAX8 in a large cohort of salivary gland tumors. Utilizing tissue microarrays, samples of normal salivary glands (n = 68) and benign and malignant salivary gland neoplasms (n = 442) were evaluated for nuclear immunoreactivity with PAX2 and PAX8. No expression was observed with either marker in the normal salivary glands, and PAX8 was negative in all neoplasms. Focal expression of PAX2 was observed in one example each of oncocytoma and acinic cell carcinoma. These results indicate that evaluation of PAX2 and/or PAX8 expression would be valuable in differentiating primary salivary gland tumors from metastases known to express PAX2 and/or PAX8.
PubMed ID: 24771139
Article Size: <1 MB
 

Oncocytic Lipoadenoma of the Salivary Gland: A Clinicopathologic Analysis of 7 Cases and Review of the Literature

Lau SK, Thompson LD.
Head Neck Pathol. 2015 Mar;9(1):39-46.
Oncocytic lipoadenoma is an exceedingly uncommon neoplasm of the salivary gland composed of oncocytic epithelium and adipose tissue. Retrospective. Seven cases of oncocytic lipoadenoma were analyzed in order to further characterize the clinical and pathologic features of this rare tumor. The patients included six males and one female who ranged from 40 to 83 years of age (mean 62 years) at presentation. All tumors arose in the parotid gland. Grossly, the tumors were solitary, well circumscribed and had light brown to yellow cut surfaces. Histologically, the tumors were composed of an admixed population of oncocytes and adipocytes in varying proportions, with the lipomatous component ranging from 5 to 70 %. Other common features included the presence of serous acini, ductal elements, sebaceous glands, and a patchy chronic inflammation. Clinical follow up information, available in all cases, with a duration of 3-148 months (mean 57 months), showed no evidence of tumor recurrence. Due to its rarity, oncocytic lipoadenoma can pose problems in diagnosis, although the distinctive morphologic features of this neoplasm allow for separation from more commonly recognized oncocytic neoplasms of the salivary glands.
PubMed ID: 24737102
Article Size: 2.2 MB
 

Papillary Cystadenoma of Minor Salivary Glands: Report of 11 Cases and Review of the English Literature.Cases and Review of the English Literature.

Tjioe KC, de Lima HG, Thompson LD, Lara VS, Damante JH, de Oliveira-Santos C.
Head Neck Pathol. 2015 Sep;9(3):354-9.
Papillary cystadenoma is a rare, benign salivary gland tumor which is well-circumscribed, containing cystic cavities with intraluminal papillary projections. Only 19 cases arising within minor salivary glands (MnSG) from the oral cavity sites have been reported in the English literature (PubMed 1958-2014). We report 11 new cases of MnSG papillary cystadenomas in conjunction with a review of the literature. Demographic information, clinical and histologic features, treatment and prognosis are compiled and discussed for all 30 cases reported in the English literature.
PubMed ID: 25547059
Article Size: 1.2 MB
 

Adenoid cystic carcinoma of the head and neck — An update

Coca-Pelaz A, Rodrigo JP, Bradley PJ, Vander Poorten V, Triantafyllou A, Hunt JL, Strojan P, Rinaldo A, Haigentz M Jr, Takes RP, Mondin V, Teymoortash A, Thompson LDR, Ferlito A.
Oral Oncol. 2015 Jul;51(7):652-661.
This article provides an update on the current understanding of adenoid cystic carcinoma of the head and neck, including a review of its epidemiology, clinical behavior, pathology, molecular biology, diagnostic workup, treatment and prognosis. Adenoid cystic carcinoma is an uncommon salivary gland tumor that may arise in a wide variety of anatomical sites in the head and neck, often with an advanced stage at diagnosis. The clinical course is characterized by very late recurrences; consequently, clinical follow-up should extend at least >15 years. The optimal treatment is generally considered to be surgery with postoperative radiotherapy to optimize local disease control. Much effort has been invested into understanding the tumor’s molecular biological processes, aiming to identify patients at high risk of recurrence, in hopes that they could benefit from other, still unproven treatment modalities such as chemotherapy or biological therapy.
PubMed ID: 25943783
Article Size: 2.6 MB
 

Parotid Gland Nodular Fasciitis: A Clinicopathologic Series of 12 Cases with a Review of 18 Cases from the Literature.

Gibson TC, Bishop JA, Thompson LD.
Head Neck Pathol. 2015 Sep;9(3):334-44.
Nodular fasciitis (NF), very uncommon in the parotid gland, is a benign myofibroblastic proliferation that may be mistaken for other neoplastic proliferations. The mass-like clinical presentation and histologic features result in frequent misclassification, resulting in inappropriate clinical management. There are only a few reported cases in the English literature. Cases within the files of the authors’ institutions (retrospective) confined to the parotid gland were compared to cases reported in the English literature (Medline 1966–2014). The patients included five females and seven males, aged 11–70 years (mean 45.2 years). All patients presented with a mass lesion, present on average 1.9 months, without a documented history of trauma. The lesions were 0.7–5.2 cm (mean 2.2 cm). Seven patients had fine needle aspiration. The majority of the lesions were circumscribed (n = 9), composed of spindle-shaped to stellate myofibroblasts (MF) arranged in a storiform growth pattern, juxtaposed to hypocellular myxoid tissue-culture-like areas with extravasation of erythrocytes. Dense, keloid-like collagen (n = 7) and occasional giant cells were seen (n = 6). Mitotic figures (without atypical forms) were readily identifiable (mean 4/10 HPFs). By immunohistochemical staining, the MF were reactive with vimentin, actins, and calponin, while the histiocytes were reactive with CD68. All patients had surgical excision. One patient developed local recurrence (12 months later). All were alive and disease free at last follow-up, with a mean 133 months of follow-up. The principle differential diagnoses include fibrosarcoma, fibromatosis, pleomorphic adenoma, myoepithelioma, neurofibroma, schwannoma, solitary fibrous tumor, leiomyoma, fibrous histiocytoma and myxoma. NF of the parotid gland occurs in middle-aged patients who present with a mass (mean 2.2 cm) in the parotid gland of short duration (1.9 months). FNA misinterpretation frequently leads to excision. Separation from myoepithelial and mesenchymal lesions affecting the parotid gland results in appropriate management.
PubMed ID: 25472697
Article Size: 3.7 MB
 
 
 
 

Functional Histology of Salivary Gland Pleomorphic Adenoma: An Appraisal.

Triantafyllou A, Thompson LD, Devaney KO, Bell D, Hunt JL, Rinaldo A, Vander Poorten V, Ferlito A.
Head Neck Pathol. 2015 Sep;9(3):387-404.
The complex microstructure of salivary gland pleomorphic adenoma is examined in relation to function. Events related to secretion of macromolecules and absorption, responses to the altered microenvironment and controversies concerning epithelial-mesenchymal transition versus modified myoepithelial differentiation are explored. Their effects on tumor cell phenotypes and arrangements are emphasized. Heterotopic differentiation and attempts at organogenesis are also considered. The approach allows interpreting microstructure independently of histogenetic perceptions, envisaging the tumor cells as a continuum, endorsing luminal structures as the principal components, and defining pleomorphic adenoma as a benign epithelial tumour characterized by variable epithelial-mesenchymal transition, secretion/differentiation and metaplasia.
PubMed ID: 25380577
Article Size: 10.5 MB