Parotid Gland Solitary Fibrous Tumor: A Case Report and Clinicopathologic Review of 22 Cases from the Literature.

Bauer JL, Miklos AZ, Thompson LD.
Head Neck Pathol. 2012 Mar;6(1):21-31.
Solitary fibrous tumors (SFTs) are rare tumors in the head and neck, and even more so in the parotid gland. 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. Twenty-one patients with parotid gland solitary fibrous tumor were compiled from the English literature (Medline 1960-2011) and integrated with this case report. The patients included 11 males and 11 females, aged 11-79 years (mean, 51.2 years), who presented with a parotid gland painless mass gradually increasing in size or with compression symptoms, with a mean duration of symptoms of 24.7 months. The mean tumor size was 4.5 cm. Grossly, all tumors were described as well-circumscribed to encapsulated, firm, homogenous white to tan masses. Seven patients had a preoperative fine needle aspiration performed, with the majority interpreted to represent pleomorphic adenoma or cementifying fibroma. Histologically, the tumors were well circumscribed, although many tumors showed focally entrapped normal salivary gland acini and ducts at the edge. The tumors were cellular, arranged in haphazard short interlacing fascicles of spindled to epithelioid cells. The spindled cells showed tapering cytoplasm with monotonous, round to oval nuclei with coarse nuclear chromatin distribution. Keloid-like to wiry collagen was present between the neoplastic cells. Mitoses were identified in most cases, while necrosis was absent. Isolated, patulous vessels were present, but a well developed ‘hemangiopericytoma-like’ vascular pattern was not seen. Three tumors were classified as malignant, showing marked nuclear pleomorphism and increased mitoses. When immunohistochemistry was performed, all tumors showed strong and diffuse vimentin, with a majority showing CD34, bcl-2 and CD99 immunoreactivity; all cases tested were negative for S100 protein, cytokeratin, EMA, CAM5.2, smooth muscle actin, muscle specific actin, desmin, MYOD1, myogenin, CD117, GFAP, CD31, FVIII-Rag, collagen IV, p63, p53, calponin, caldesmon, CD56, NFP, and ALK-1. The principle differential diagnoses include pleomorphic adenoma, myoepithelioma, nodular fasciitis, schwannoma, fibromatosis coli, spindle cell ‘sarcomatoid’ carcinoma, and spindle cell melanoma. All patients were managed with surgery, while two patients also received radiation therapy. Metastatic disease was identified in one patient immediately after excision. All patients with follow-up were alive without evidence of disease (n = 18), but the average follow-up is only 1.9 years. One patient is alive with disease at 12 months. Parotid gland SFT is a rare tumor, usually presenting in middle aged adults as a slowly growing mass. Characteristic histologic appearance with CD34 and bcl-2 immunoreactivity support the diagnosis. Surgery is the treatment of choice to yield a good outcome.
PubMed ID: 22002440
Article Size: 1 MB
 

Kaposi sarcoma of major salivary gland origin: A clinicopathologic series of six cases.

Castle JT, Thompson LD.
Cancer. 2000 Jan 1;88(1):15-23.
BACKGROUND: Kaposi sarcoma (KS), one of the defining tumors of acquired immune deficiency syndrome (AIDS), is rarely identified in the major salivary glands. To the authors’ knowledge, no previous published series has evaluated the clinicopathologic aspects of this tumor in major salivary glands.
METHODS: Six cases of salivary gland KS, diagnosed between 1970 and 1998, were retrieved from the files of the Oral and Maxillofacial Pathology Registry of the Armed Forces Institute of Pathology. Histologic features were reviewed and special stains, immunohistochemical studies, and in situ hybridization were performed (n = 4). Patient follow-up data were obtained.
RESULTS: The patients included 6 men ages 20-73 years (average, 53.0 years). Patients presented clinically with a mass in the submandibular (n = 4) or parotid (n = 2) gland region. Symptoms were present for a mean of 13.7 months. The tumors measured 1-4 cm (average, 2.5 cm) in greatest dimension. Histologically, the tumors exhibited the usual features of KS: a spindle cell vascular proliferation arranged in fasciculated bundles, variable nuclear pleomorphism, mitotic figures, extravasated erythrocytes, and hyaline globules. Five patients were serologically positive for human immunodeficiency virus (HIV) (three homosexual males, one infected by a contaminated blood transfusion, and one with an unknown risk factor). Human herpesvirus-8 (HHV-8) was present in all cases tested (n = 4). Patients were treated with surgical excision (n = 6), followed by chemotherapy (n = 1) for the single patient with other foci of KS (rectal). Three patients died of AIDS-related infectious complications and one of congestive heart failure, whereas the remaining patients are alive with AIDS but free of salivary gland KS.
CONCLUSIONS: Salivary gland enlargement is frequently identified in HIV positive or AIDS patients. Although rare, it is important to consider KS in the differential diagnosis of other AIDS-related salivary gland manifestations (infections and tumors). Copyright 2000 American Cancer Society.
PubMed ID: 10618601
Article Size: 1 MB
 

Oncocytomas of the submandibular gland. A series of 22 cases and a review of the literature.

Thompson LD, Wenig BM, Ellis GL.
Cancer. 1996 Dec 1;78(11):2281-7.
BACKGROUND: Oncocytomas are benign salivary gland neoplasms that represent approximately 1.5% of all salivary gland tumors. Oncocytomas of the submandibular gland, however, are decidedly uncommon.
METHODS: Twenty-two cases of submandibular gland oncocytomas from the files of the Oral and Otolaryngic Tumor Registries of the Armed Forces Institute of Pathology were reviewed, and analysis of the histologic criteria, histochemical and immunohistochemical reactions, and ultrastructural and clinical follow-up data was performed.
RESULTS: The patients included 11 females and 11 males, age 21-88 years, with a mean age at presentation of 58.7 years. Clinically, the tumors were generally asymptomatic masses in the submandibular gland that increased in size over a period ranging from several weeks to 20 years and were occasionally associated with pain (n = 9). The tumors ranged in greatest dimension from 0.7 to 7 cm and were circumscribed to encapsulated. Histologically, the tumors were characterized by large epithelial cells with eosinophilic, granular cytoplasm. The cytoplasm stained positively with stains used to demonstrate mitochondria (phosphotungstic acid-hematoxylin, Novelli, Cresylecht violet V, and Kluver-Barrera Luxol fast blue stains). Immunohistochemical reactions demonstrated an epithelial origin (keratin and epithelial membrane antigen), whereas markers for myoepithelial derivation (S-100 protein, actin, and glial fibrillary acidic protein) were not identified. At the time this study was conducted, all patients with submandibular oncocytomas were either alive without evidence of disease or had died without evidence of recurrent disease, with surgical resection the only treatment.
CONCLUSIONS: Submandibular gland oncocytomas are rare, benign tumors. The tumor cells are filled with mitochondria, which are easily demonstrated by histochemical reactions. Complete surgical resection is adequate therapy.
PubMed ID: 8940996
Article Size: <1 MB
 

Mucocele: Retention and extravasation types.

Thompson LD.
Ear Nose Throat J. 2013 Mar;92(3):106-8.
FIRST PARAGRAPHS: The extravasation type is the most common mucocele, more common in children and young adults, with a peak in the second decade of life. The most common non-neoplastic lesion of salivary gland tissue is the mucocele (also called sialocele and ptyalocele). A mucocele is defined as the pooling of mucin in a cystic cavity. Two types of mucoceles are recognized: (1) the retention type, in which the mucin pooling is confined within a dilated excretory duct or cyst, and (2) the extravasation type, in which mucin is spilled into the connective tissues from a ruptured or traumatized salivary gland duct.
PubMed ID: 23532645
Article Size: <1 MB

Adenoid Cystic Carcinoma With Striking Tubular Hypereosinophilia: A Unique Pattern Associated With Nonparotid Location and Both Canonical and Novel EWSR1::MYB and FUS::MYB Fusions

Weinreb I, Rooper LM, Dickson BC, Hahn E, Perez-Ordonez B, Smith SM, Lewis JS Jr, Skalova A, Baněčková M, Wakely PE Jr, Thompson LDR, Rupp NJ, Freiberger SN, Koduru P, Gagan J, Bishop JA.
Am J Surg Pathol. 2023 Apr 1;47(4):497-503. doi: 10.1097/PAS.0000000000002023. Epub 2023 Mar 15.
The classification of salivary gland tumors is ever-evolving with new variants of tumors being described every year. Next-generation sequencing panels have helped to prove and disprove prior assumptions about tumors’ relationships to one another, and have helped refine this classification. Adenoid cystic carcinoma (AdCC) is one of the most common salivary gland malignancies and occurs at all major and minor salivary gland and seromucous gland sites. Most AdCC are predominantly myoepithelial and basaloid with variable cribriform, tubular, and solid growth. The luminal tubular elements are often less conspicuous. AdCC has largely been characterized by canonical MYB fusions, with MYB::NFIB and rarer MYBL1::NFIB. Anecdotal cases of AdCC, mostly in nonmajor salivary gland sites, have been noted to have unusual patterns, including squamous differentiation and macrocystic growth. Recently, this has led to the recognition of a subtype termed “metatypical adenoid cystic carcinoma.” Another unusual histology that we have seen with a wide range of architecture, is striking tubular hypereosinophilia. The hypereosinophilia and luminal cell prominence is in stark contrast to the vast majority of AdCC that are basaloid and myoepithelial predominant. A total of 16 cases with tubular hypereosinophilia were collected, forming morular, solid, micropapillary, and glomeruloid growth, and occasionally having rhabdoid or Paneth-like cells. They were subjected to molecular profiling demonstrating canonical MYB::NFIB (5 cases) and MYBL1::NFIB (2 cases), as well as noncanonical EWSR1::MYB (2 cases) and FUS::MYB (1 case). The remaining 6 cases had either no fusion (3 cases) or failed sequencing (3 cases). All cases were present in nonmajor salivary gland sites, with seromucous glands being the most common. These include sinonasal tract (7 cases), laryngotracheal (2 cases), external auditory canal (2 cases), nasopharynx (1 case), base of tongue (2 cases), palate (1 case), and floor of mouth (1 case). A tissue microarray of 102 conventional AdCC, including many in major salivary gland sites was examined for EWSR1 and FUS by fluorescence in situ hybridization and showed that these novel fusions were isolated to this histology and nonmajor salivary gland location. In summary, complex and striking tubular hypereosinophilia and diverse architectures are present within the spectrum of AdCC, particularly in seromucous gland sites, and may show variant EWSR1/FUS::MYB fusions.
PubMed ID: 36920022
Article Size: 1.06 MB

IgG4-Related Sialadenitis.

Thompson LDR.
Ear Nose Throat J. 2021 Sep;100(5_suppl):531S-532S. doi: 10.1177/0145561319890153.
FIRST PARAGRAPH: IgG4-related sialadenitis, formally Ku¨ttner tumor, is a chronic fibroinflammatory tumefactive salivary gland disorder characteristically showing dense lymphoplasmacytic infiltrate, storiform fibrosis, phlebitis, and increased IgG4-positive plasma cells, often with elevated serum IgG4 concentrations. This immune-mediated disorder often has systemic findings, including autoimmune pancreatitis, retroperitoneal fibrosis, cholangitis, lacrimal gland dacryoadenitis, Riedel thyroiditis, and other glands affected by a similar inflammatory fibroblastic disorder. The disorder is characterized by a prominent lymphoplasmacytic infiltrate and cytotoxic T-cell populations. In some submandibular cases, sialolithiasis may be a confounding factor.
PubMed ID: 31760789
Article Size: <1 MB

Epithelial-myoepithelial carcinoma.

Folk GS, Thompson LD.
Ear Nose Throat J. 2006 Apr;85(4):214, 216.
FIRST PARAGRAPH: Epithelial-myoepithelial carcinoma (EMC) is an uncommon salivary gland malignancy, representing 1% of all salivary gland tumors. Women are more frequently affected (2:1). The incidence of EMC peaks between the ages of 50 and 60 years, although the age range is broad. The parotid gland is most frequently affected (60%), but both major and minor salivary glands can be involved. Patients typically present with a painless, slowly growing mass; occasionally there is rapid growth, pain, or facial weakness.
PubMed ID: 16696350
Article Size: <1 MB

Hemangioma of the parotid.

Thompson LD.
Ear Nose Throat J. 2002 Nov;81(11):769.
FIRST PARAGRAPH: Hemangiomas are benign tumors of endothelial cell origin (benign hemangioendotheliomas). They are the most common salivary gland tumor in children younger than 1 year of age, accounting for 90% of cases. Hemangiomas in adults are uncommon. The characteristic features of hemangiomas are the rapid enlargement of a unilateral (usually on the left), compressible, bluish mass shortly after birth, particularly in girls. Hemangiomas are not associated with any syndrome.
PubMed ID: 12472029
Article Size: <1 MB

Mucoepidermoid carcinoma.

Thompson LD.
Ear Nose Throat J. 2005 Dec;84(12):762-3.
FIRST PARAGRAPH: Mucoepidermoid carcinoma (MEC) is the most common primary salivary gland malignancy, accounting for approximately 25% of all malignancies. More than half of these cases involve the major salivary glands, primarily the parotid glands. MEC can also involve a variety of other sites that have minor mucoserous glands. Women are more commonly affected than men (3:2), and the mean age at onset is in the 5th decade of life. MEC is also the most common salivary gland malignancy in children.
PubMed ID: 16408550
Article Size: <1 MB

Papillary cystadenoma lymphomatosum (Warthin tumor).

Rizzi MD, Thompson LD.
Ear Nose Throat J. 2003 Dec;82(12):920-2.
FIRST PARAGRAPH: Papillary cystadenoma lymphomatosum (Warthin tumor, adenolymphoma) is a benign salivary gland tumor that occurs almost exclusively in the parotid gland. It represents 5 to 6% of all salivary gland tumors, and it is the second most common benign parotid neoplasm. Men are affected more often than women, usually in the fifth to seventh decades of life, although this gender proportion is changing. Warthin tumor is associated with smoking. The most common clinical manifestation is a painless, slowly growing mass in the inferior pole of the superficial lobe of the parotid gland, usually at the level of the mandibular angle. Multifocality occurs in up to 14% of cases; when two salivary gland neoplasms are present synchronously, Warthin tumor is the most common second tumor.
PubMed ID: 14702874
Article Size: <1 MB

Invited Review: An update on salivary gland pathology.

Müller S, Thompson LD.
Head Neck Pathol. 2013 Jul;7 Suppl 1:1-2.
FIRST PARAGRAPH: Over the past few decades, salivary gland tumor pathology has evolved. This includes recognition of newly defined entities as well as reclassification of other salivary gland tumors [1]. The development of genetic tests have shown that some salivary gland tumors have genetic abnormalities which are specific to a histologic type such as MECT1/ MAML2 gene fusion in mucoepidermoid carcinoma and PLAG1 or HMGA2 gene translocation in pleomorphic adenoma. Immunohistochemical studies have aided in both the diagnosis and prognosis of salivary gland tumors. High Ki67 is correlated with poor overall survival in mucoepidermoid carcinoma, acinic cell carcinoma and adenoid cystic carcinoma. High MUC1 in mucoepidermoid carcinoma is associated with higher grade and high recurrence while MUC4 is associated with a lower grade tumor and longer disease free survival. The finding of androgen receptors in salivary duct carcinoma has led to new therapies as these tumors are shown to be responsive to androgen deprivation therapy. Newly described salivary gland entities in the past 20 years include both benign (sclerosing polycystic adenosis, sialolipoma) and malignant (cribriform adenocarcinoma of the tongue, mammary analogue secretory carcinoma) tumors [2]. Newly recognized histologic variants of well-known salivary gland tumors have been reported, to include salivary-duct carcinoma, acinic cell carcinoma and epi-myoepithelial carcinoma.
PubMed ID: 23821215
Article Size: <1 MB