Two cases of anorectal malignant melanoma

Case 1. The patient was a 69-year-old female, who had a black nodule at the dental line. An excisional biopsy specimen from the lesion revealed malignant melanoma. She underwent an abdominoperineal resection and postoperatively received 5 courses of DAV (DTIC, ACNU,and VCR) therapy. The patient has been disease-free for 3 years and 5 months after the operation without any signs of recurrence. Case 2. The patient was a 74-year-old male, who had previously undergone local resection of an anorectal tumor with anal bleeding, and was diagnosed with anorectal malignant melanoma at another hospital before admission into our institution. One year and two months after the first resection, local recurrence was detected at the rectum, and he underwent an abdominoperineal resection in the same hospital. Two months later, he presented with multiple metastatic lesions (stomach, rectum and celiac and pelvic lymph nodes) and was admitted to our hospital. Here, the patient received DAC-Tam (DTIC, ACNU, CDDP and Tamoxifen) therapy. During 5 courses of the chemotherapy, the gastric lesion was significantly reduced in size and the rectal lesion became stable. Thus, although he was able to intake orally, the chemotherapy was useful from the viewpoint of QOL. Subsequently, multiple skin metastases developed and CDV (CDDP, DTIC and VDS) combined chemotherapy was initiated. After the second chemotherapy course, brain metastasis appeared and the patient died of melanoma 16 months after the start of chemotherapy and 33 months after the initial diagnosis of anorectal malignant melanoma.