A rare case of primary malignant melanoma of the scrotum diagnosed by fine-needle aspiration.

We report a case of a 55-yr-old man with malignant melanoma of scrotum. He was referred to our Hospital with a complaint of gradual focal enlargement of the scrotum in a period of 3 yr. On physical examination, a pigmented, poorly marginated mass, with central necrosis was observed. A fine-needle aspiration (FNA) of the lesion was performed. Cytological examination revealed highly cellular smears, containing malignant cells, dispersed or arranged in loose aggregates. Cellular morphology and characteristics were identical to those of malignant melanoma arising elsewhere in the skin. The immunocytochemical study revealed positivity of neoplastic cells for anti-melanoma monoclonal antibody (HMB-45) antigen. Histological confirmation finally was provided after wide excision of the lesion. We emphasize the difficulties in differential diagnosis considerations and diagnostic pitfalls of scrotal lesions.