Melanoma of the soft parts: diagnosis of metastatic and recurrent tumors by aspiration cytology.

Three cases of melanoma of the soft parts diagnosed by aspiration cytology and immunochemistry are described. Unusual clinicoradiological features, variable cytomorphology, absence of melanin, and lack of awareness due to rarity of the lesion caused diagnostic dilemma. Morphological similarity to alveolar soft part sarcoma, synovial and epithelioid sarcoma, cutaneous melanoma, poorly differentiated carcinoma, and plasmacytoma were noted. Consideration of clinical data such as age, site, and radiology was helpful in narrowing down the diagnosis. A presumptive cytologic diagnosis helped in selecting the antibody panel, which established the definitive diagnosis in all cases. This approach is valuable in preoperative management and obviates the need for an open biopsy in primary, metastatic, or recurrent tumor. Increasing experience in fine-needle aspiration of this rare entity and correlation with immunochemistry and histopathology are valuable in narrowing down the differential diagnosis, reducing diagnostic errors, and widening its clinicocytological spectrum. Copyright 2003 Wiley-Liss, Inc.