Needle aspiration of metastatic melanoma.

Needle aspiration of nodal and extranodal metastases of malignant melanoma was evaluated in 74 patients. All patients had the initial diagnosis of malignant melanoma established on surgical biopsy and histologic sections. A 20-cc glass syringe and an 18-gauge needle were used, and the material obtained was stained by the Wright-Giemsa technique. Adequate material was obtained, and a cytologic diagnosis of malignant melanoma was made in 67 patients (90.5%). In seven patients (9.5%) the specimens contained nondiagnostic material. The diversity of cell types, cytoplasm staining affinity and pigmentation is described. Despite the high variability of the cytologic features encountered, malignant melanoma usually can be diagnosed on cytologic smears. Difficulties in recognizing the nonpigmented varieties are emphasized. The procedure was well tolerated, and no complications were seen.