Abstract
The case involved a 77-year-old woman who had been followed after surgical excision of malignant melanoma of the paranasal sinus with adjuvant chemotherapy at the age of 72. A follow-up CT scan suggested thickening of the gastric wall and gastrointestinal close examinations were performed. Upper gastrointestinal endoscopy revealed no abnormalities, but colonoscopy disclosed a type I tumor at the transverse colon. A biopsy yielded a diagnosis of malignant melanoma. Colonic metastasis of malignant melanoma of the paranasal sinus was likely. The patient became to show symptoms of intestinal obstruction due to the tumor, so that partial resection of the transverse colon was carried out. According to “the General Rules for Colorectal Cancer Study”, the pathological findings of the resected specimen included Type 1, 38 x 35 x 20 mm in size, pSS, med, INFa, ly2, vl, pN0, pPM0, pDM0, and pRM0. On immunohistochemistry the cells were S-100 (±), HBM45 (+), melan-A (±), CD117 (+) and p53 (+).
It is rare that malignant melanoma metastasizes to the gastrointestinal organs and is surgically managed. Such metastasis involving the colon like in this case is especially uncommon. This case with some bibliographic comments is reported here.
