Abstract
We report a case of metachronous anal metastasis from sigmoid colon cancer.
A 68-year-old man who underwent sigmoidectomy for sigmoid colon cancer in January 2006 was found to have a metastatic liver tumor located in the S7 by a follow-up abdominal CT scan 12 months after the operation. He underwent partial hepatectomy. Twenty-one months after his initial surgery, he complained of anal pain. Imaging studies revealed an anal tumor. On digital examination, a tumor 2 cm in diameter was felt in the subcutaneous structure on the dorsal aspect of the anus. This tumor was suspected of metastasis from sigmoid colon cancer, and abdominoperineal resection of rectum was performed. Histologically the tumor was classified into moderately differentiated adenocarcinoma and was considered to be metastasis from the primary sigmoid colon cancer. We have reported this case because it appears to be an interesting and uncommon disease.
