[A case of clear cell sarcoma of tendons and aponeuroses with a large amount of melanin--malignant melanoma of the soft part].

We report a 62-year-old male with a clear cell sarcoma of tendons and aponeuroses arising in the area of the M. flexor carpi ulnaris. Grossly, the tumor had a black appearance. Light microscopic inspection showed a large amount of melanin. Electron microscopically, the tumor pigment was located within melanosomes. The possibility that the tumor represents a neural crest-derived melanotic tumor (malignant melanoma) of the soft part is discussed.