[A case of colon cancer with extramural progression].

An 84-year-old man was admitted to our hospital because of anemia and occult blood. A huge abdominal mass (12 cm on diameter) was palpable in his right upper abdomen. Colonoscopy showed Type 3-like tumor with a large ulcer in the transverse colon, and the biopsy specimen indicated moderately differentiated adenocarcinoma. The tumor had progressed far beyond the colonic wall to form a huge mass with the direct invasion into the stomach. We diagnosed this case as extramural growth type colon cancer, and he underwent a partial colectomy and sub-total gastrectomy and he has no recurrence for 11 months after the operation. Colorectal cancer presenting extramural growth is rare. We studied related factors causing such rare growth types according to summaries of the 27 cases reported in Japan and we also studied the strongly positive immunohistochemical activity of E-cadherin, a cell adhesion molecule, in this case.