A 65-year-old male noticed an itchy eruption in the scrotum and the right axilla beginning 4 years ago, and then a tumor formation in his right axilla 3 years ago. At first examination, a bean-sized tumor was found in a nut-sized brown spot in his right axilla. There were three depigmented spots which sizes were up to a thumb-head sized, located in the scrotum. Paget's cells were detected in both the axilla and scrotum by biopsy. No macroscopic eruption was seen in the other external pudendal regions or the left axilla. On January 12, 1994, the tumor site in the right axilla was removed totally with the skin and the auxiliary lymph nodes, and it was closed by a myocutaneous flap. A resection was also made at the depth of the fatty tissue, which was 3 cm apart from the eruption margin, in the external pudendal site, and a mesh skin graft was performed. In the axilla, the tumor cells infiltrated into the region from the epidermis to the dermis. Although it was suspected that those cells might infiltrate the vessels, there were no metastasis to the axillary lymph nodes. In the specimens obtained from the resected external pudendal site, the tumor cells were found in only the epidermis, and those cells were not seen in all resected edges. Four courses of VAM-UFT therapy were conducted. On December 5, 1994, new depigmented spots and erosion were found in the external pudendal site. Because Paget's cells were found in biopsy, the region was removed with the skin 2 cm apart from the border of the eruption. The tumor cells infiltrated partially into the dermis, and also into the previous skin grafts. We performed PCNA staining on paraffin embedded tissue to know the cell proliferation ability on each specimens obtained in the surgical operation. The cell proliferation ability reduced in the axillary tumor, which originally occurred, and increased in the eruptions which recurred.