A Case of Juvenile Polyposis Accompanied by Transverse Colon Adenoma in Whom Total Colectomy was Performed

A fifty-six years-old man without a particular colorectal family history was referred to a near-by clinic due to anemia found during a health care examination. At the clinic, multiple colon polyps and a tumor in the transverse colon were found as a result of barium enema examination. He was referred to our hospital and, by means of colonoscopic examination, numerous pedunculated type polyps were identified from the cecum through the rectum. Colonoscopic polypectomy was performed on some of the ascending colon polyps. Since a tumor-like lesion with a diameter of 4cm was also identified by enhanced CT, total colectomy was performed. By histopathological examination, pedunculated polyps densely distributed around the rectum and polyps of ascending colon were diagnosed as juvenile polyps and a tumor in the transverse colon was identified as tubulovillous adenoma (severe atypia). Compared with adenomatous polyposis, cases of juvenile polyposis have been reported as being poorly related with malignant tumors since it is classified as a teratoma. However, the number of reports in which juvenile polyposis may represent a pre-cancerous state have been increasing. Here we report a case of juvenile polyposis accompanied by tubulovillous adenoma with severe atypia, as well as on a review of related papers.