Is fine needle aspiration cytology (FNAC) useful in skin adnexal masses? A study on 5 cases of pilomatixoma.

Superficial cutaneous/subcutaneous nodules, caused by a variety of inflammatory, benign and malignant pathology of diverse origin, are tempting lesion for fine needle aspiration cytology (FNAC). Amongst these, adnexal tumor show considerable overlap, both in clinical manifestation as well as in histopathology. Archieval records of clinical findings, FNAC smears and reports pertaining to 5 histologically proved cases of pilomatricoma (PMX) were analyzed. Different cytological findings were graded + to +++. Pre FNAC clinical diagnoses were sebaceous cyst, tuberculous lymphadenopathy, dermatofibroma, reactive lymphadenopathy and lipoma. PMX was diagnosed on FNAC in 3 cases on finding groups of basaloid cells, ghost epithelial cells, pink fibrillary material and calcium deposits. Other cases were diagnosed as epidermal inclusion cyst with the differential diagnosis of well differentiated squamous cell carcinoma and skin appendageal tumor of undetermined origin in one case each. In all the cases, FNAC established epithelial nature of the lesion, excluding clinically mimicking inflammatory/neoplastic lesions of other origin. FNAC should be followed by excision biopsy to accurately type the epithelial neoplasm.