This is the first report of a metastatic colon cancer of breast cancer positive for estrogen receptor. A 56-year-old woman who had undergone standard radical mastectomy due to right breast cancer was suffered from left lower abdominal pain. Barium enema and proctoscopy revealed a narrowing at the rectum and the descending colon. Needle biopsy of the rectum revealed Group 5. The resection of the left colon, the rectum and the ovaries were performed. Foci were macroscopically present at the rectum, the sigmoid colon and the descending colon. Histological examination revealed that colonic foci were metastases from the breast cancer of lobular carcinoma. The colonic preparation was positive for estrogen receptor
