Anorectal malignant melanoma: report of a case.

A 74-year-old woman presented with anal bleeding and a protuberant mass. A biopsy of the mass revealed the proliferation of spindle-shaped cells with melanin pigments, and an abdominoperineal resection was performed, the histology of which confirmed malignant melanoma. Surgery was absolutely noncurative because massive metastases were encountered in the pelvic and paraaortic lymph nodes. However, postoperative chemotherapy, composed of decarbazine (DTIC), vincristine (VCR), and nimustine hydrochloride (ACNU), achieved satisfactory results. The patient has been well without any evidence of recurrence for more than 3 years.