Eccrine Spiradenoma Mimicking Adenoid Cystic Carcinoma on Fine Needle Aspiration

Abstract

BACKGROUND: Although the cytologic features of salivary gland tumors are well recognized, an adnexal skin tumor occurring in the same region, on occasion, may resemble and be confused with a salivary gland neoplasm. CASE: A case of eccrine spiradenoma presented as a painful mass in the region of the parotid that mimicked an adenoid cystic carcinoma on fine needle aspiration cytology. CONCLUSION: Fine needle aspirates of eccrine spiradenoma, a benign cutaneous adnexal tumor, may have findings that mimic those of adenoid cystic carcinoma. Both may have cell balls and rosettelike structures surrounding stromal matrix cores. Recognition of three cell types in eccrine spiradenomas, including epithelial cells, myoepithelial cells and lymphocytes, as compared to a single cell type in adenoid cystic carcinoma, is paramount in avoiding this potential pitfall in cytologic diagnosis.