Sclerosing sweat duct carcinoma in the peri-anal skin: a case report.

We report a case of sclerosing sweat duct carcinoma, a rare tumor, occurring in the peri-anal skin, a rare position. The patient, a 41-year-old Japanese woman, was admitted to our hospital with recurrence of sclerosing sweat duct carcinoma in the peri-anal skin, which had been initially resected at a local hospital. She underwent abdomino-perineal resection. No lymph node metastases or distant metastases were found. Although we allowed a 2-cm resection margin around the tumor, microscopy showed that the tumor had extended to within 2 mm of this margin at several sites, indicating that sclerosing sweat duct carcinoma is locally aggressive. An ample resection margin should therefore be taken at initial surgery for this type of tumor. Moreover, surgical excision that is wider and deeper than primary excision is required when this tumor recurs.