Breast carcinoma metastatic to a solitary adenomatous polyp in the colon

A 70-year-old woman with known metastatic breast cancer was found at autopsy to have widely disseminated, poorly differentiated adenocarcinoma. An incidental adenomatous polyp of the colon also contained metastatic breast carcinoma. This is the first report, to our knowledge, of a metastasis to an adenomatous polyp of the colon.