@article{oai:u-ryukyu.repo.nii.ac.jp:02015978, author = {Miyazato, Hiroshi and Yamada, Mamoru and Tamai, Osamu and Matsumoto, Mitsuyuki and Shiraishi, Masayuki and Kusano, Toshiomi and Muto, Yoshihiro and Kiyuna, Masaya and Toda, Takayoshi and Nakasone, Katsu}, issue = {3}, journal = {琉球医学会誌 = Ryukyu Medical Journal}, month = {}, note = {A case of anorectal amelanotic melanoma in a 72-year-old female is reported. The patient presented with several episodes of anal bleeding after defecation. Endoscopic examination showed a 1 cm-polypoid tumor with a roughly irregular surface in the right wall of the anorectum about 5 cm from the anal verge. No pigmentation was evident in the tumor. Endoscopic ultrasonography (EUS) revealed the depth of invasion to be limited to the submucosa. Although poorly differentiated adenocarcinoma was suspected by biopsy, it was difficult to classify the tumor as malignant lymphoma or malignant melanoma. Transanal simple excision of the tumor was performed. The tumor appeared homogeneously gray-whitish and was 10x17 mm in size. The tumor was finally diagnosed to be amelanotic melanoma by electron microscopy and immunohistochemistry. The depth of invasion was limited to the submucosa. The tumor was resected with 1 cm-free margins. A few decades ago, abdominoperineal resection combined with or without pelvic and bilateral inguinal lymph node dissection was recommended for the patients who had anorectal malignant melanoma with no distant metastases. However, recent studies have demonstrated that overall survival is related to the tumor size and staging of the depth of invasion, but not the extent of surgical margins. So we didn't perform additional resection. She is now living and well 11 months after operation with no evidence of recurrence of the disease. She comes to the hospital every three months., 論文}, pages = {147--151}, title = {[症例報告]Primary amelanotic melanoma of the anorectum : A case report and literature review}, volume = {15}, year = {1995} }