Malignant melanoma cells in the eccrine apparatus.

A case of malignant melanoma arising on the sole of a 75-year-old Japanese man is presented. Histopathologically, in addition to the intraepidermal and intradermal malignant melanoma cells reaching the upper part of the dermis, cells were also found in the deep part of the ductal epithelium of the eccrine apparatus. Melanoma cells, and melanocytic nevus cells as well, are rarely found within the epithelial structure of sweat glands, yet they are frequently found in that of hair follicles. In order to avoid a residue of melanoma cells in the deep part of the eccrine apparatus, a fairly deep excision should be performed even for this melanoma.