Cytomorphologic features of sebaceous carcinoma on fine needle aspiration

OBJECTIVE: To describe three cases of sebaceous carcinoma metastatic to reg ional lymph nodes diagnosed by fine needle aspiration (FNA). STUDY DESIGN: FNA was performed using standard techniques. A portion of eac h specimen was stained with Diff-Quik(R) (Dade, Miami, Florida, U.S.A.); an other portion was fixed in 95% ethanol and stained with a modified Papanico laou stain or fixed in formalin and stained with hematoxylin and eosin. RESULTS: All carcinomas were moderately cellular, with primarily irregular cell clusters. The cytoplasm was finely reticular and contained variable nu mbers of small vacuoles. Nuclei were centrally located and pleomorphic and contained coarse chromatin. Variably sized but often large nucleoli were se en. Mitotic figures were easily identified. CONCLUSION: Sebaceous carcinoma is a rare but cytologically distinct neopla sm, It frequently metastasizes to regional lymph nodes and may then appear as a mass amenable to FNA. Aspiration cytologists, particularly who aspirat e head and neck lesions, should be familiar with the distinct features of t his neoplasm.