[A Case of Adenosquamous Carcinoma of the Ascending Colon].

We report a case of adenosquamous carcinoma of the colon. A 70-year-old woman underwent a colonoscopic examination because of a positive fecal occult blood test. Colonoscopy demonstrated a type 2 tumor of the ascending colon, and a biopsy specimen showed poorly-moderately differentiated tubular adenocarcinoma. We performed a right hemicolectomy with D2 lymphadenectomy. The histopathology of the tumor demonstrated adenosquamous adenocarcinoma. Primary adenosquamous carcinoma of the colon is relatively rare and has a poor prognosis. Therefore, adenosquamous carcinoma of the colon may require strict follow-up.