Rectal villous tumors developing after resection of colon cancer

We experienced three patients who developed villous tumors in the rectum after resection of colon carcinoma. They were all men, one had ascending colon cancer and two had sigmoid colon cancer as the primary lesion. All three patients developed severe watery diarrhea during postoperative follow-up at 7 to 35 months after colectomy. The three rectal tumors were considered to be a metachronous lesions with rapid growth. There are no synchronous or metachronous colorectal carcinomas among another 23 patients with rectal villous tumors treated at our institution. Our findings suggested that villous tumors of the rectum might have a specific pathogenesis.