[A Case of Poorly Differentiated Adenocarcinoma of the Colon with Rapid Postoperative Progression Suggestive of Peritoneal Dissemination].

A 62-year-old man was admitted to our hospital because of pain in the right lower abdomen and was diagnosed with cecal cancer and an associated abscess. The patient subsequently underwent right hemicolectomy. Histopathological examination was positive for por1, se, bd3, ly3, v0, PM0, and DM0. He was discharged from the hospital 21 days postoperatively. He was hospitalized with bloating of the right lower abdomen and inflammation 31 days postoperatively. He was later diagnosed with recurrence of the initial abscess, but his symptoms did not improve, and he was considered to have peritoneal dissemination. His general condition deteriorated rapidly, and he died approximately 1.5 months postoperatively. Histopathological and anatomical examination later confirmed multiple organ failure with peritoneal dissemination. It is reported that prognosis of poorly differentiated adenocarcinoma is worse than that for well- or moderately differentiated adenocarcinoma. Poorly differentiated adenocarcinoma may recur immediately after curative surgery.