Fine‐needle aspiration cytomorphology of sebaceous lymphadenoma of the salivary gland

Abstract

Sebaceous lymphadenoma (SLA) is a histologic variant of lymphadenoma or sebaceous adenoma of the salivary gland. The fine-needle aspiration (FNA) cytology of SLA has not been well-described. In this report, we reported a case that involved an 81-year-old male with a long-standing left parotid mass and was diagnosed on FNA cytology. The FNA smears showed clusters of three types of epithelial cells in a background of abundant lymphoid cells, macrophages and abundant proteinaceous materials. The predominant epithelial cells were large polygonal cells with abundant cytoplasm filled with multiple, uniform, small, and clear vacuoles, ill-defined cytoplasmic borders, and small centrally located round nuclei with finely granular chromatin, conspicuous nucleoli and indented nuclear membranes apparently imprinted by cytoplasmic vacuoles. These cells were surrounded by polygonal or flat cells with less or more dense cytoplasm, indistinct cell borders and round or oval small nuclei with smooth nuclear membranes, which correspond to germinative or basaloid cells. Some cells had granular cytoplasm. Large three dimensional clusters of nonkeratinized squamous cells have oval nuclei containing evenly distributed chromatin, and scant to moderate dense cytoplasm that were arranged in a "stream of fish" pattern. Rare granulomas and cystic contents (degenerated cells, inflammatory cells, macrophages, and abundant granular debris/proteinaceous material) were also seen. The diagnosis of SLA was confirmed by the surgical resection.

Cytologic features of sebaceous, lymphadenoma, and sebaceous lymphadenocarcinoma: Differential diagnostic considerations

“…Even when the tumor is unencapsulated, it is invariably well circumscribed and pushes against but does not infiltrate the adjacent parenchyma. The cytologic findings observed in our three cases are similar to those previously described . These reports uniformly document a mixed lymphoid background, which may include plasma cells and tangible body macrophages.…”

“…Few reports of the cytologic appearance of sebaceous neoplasms of the salivary glands exist . Only a single report has a description of the cytologic findings of a sebaceous lymphadenocarcinoma .…”

“…In some cases, sebaceous lymphadenomas will form a well-developed capsule but this capsule is often incomplete or on occasion completely absent.Even when the tumor is unencapsulated, it is invariably well circumscribed and pushes against but does not infiltrate the adjacent parenchyma. The cytologic findings observed in our three cases are similar to those previously described [9][10][11][12][13][15][16][17]. These reports uniformly document a mixed lymphoid background, which may include plasma cells and tangible body macrophages.…”

“…Few reports of the cytologic appearance of sebaceous neoplasms of the salivary glands exist. [4][5][6][7][8][9][10][11][12][13][14][15] Only a single report has a description of the cytologic findings of a sebaceous lymphadenocarcinoma. 4 In that report, the features of touch preparations were described.…”

Cytological features of the Warthin‐like variant of salivary mucoepidermoid carcinoma

“…The other less common diagnostic considerations include lymphadenoma and lymphoepithelial cyst. Extravasated sebum and sebaceocytes may be seen in sebaceous lymphadenoma . Basaloid type epithelium and basement membrane material are noted in nonsebaceous lymphadenoma .…”