Quick diagnosis of malignant melanoma with the touch-fluorescence method during operation.

Nine cases of primary melanotic melanoma, three cases of metastatic amelanotic melanoma, and 26 cases of pigmented and unpigmented tumors other than melanoma were examined with the touch-fluorescence method using preparations from the cut surface of the lesions. Fluorescent melanoma cells were easily detected with a fluorescence microscope in all the cases of malignant melanoma whether the melanoma was melanotic or amelanotic. The fluorescent melanoma cells could be divided into three types by configuration: round, spindle-shaped, and pleomorphic. The main cell type of superficial spreading melanoma was round and that of nodular melanoma and acral lentiginous melanoma was chiefly pleomorphic. Fluorescent tumor cells were not seen in pigmented and unpigmented tumors other than melanoma, except in pigmented basal cell epithelioma; this fact made it possible to apply this method routinely for quick diagnosis of malignant melanoma during operation.