A case of colonic muco-submucosal elongated polyp (CMSEP) with various forms of polyps in the cecum

A 57 years old male was referred to our hosphtal because of abdominal discomfort. On barium enema and colonoscopic examination, there were various forms of polyps including pedunculated polyps with a elongated stalk, measuring 70mm in maximal length and small hemispherical polyps in the cecum. In addition, there were ulcer scars at the same site. Endoscopic polypectomy was performed and the resected specimen was characterized by submucosal tissue, which were mainly composed of normal mucosa and edematous submucosal layer with loose fibrous connective tissues. Thus, the resected polyp was diagnosed as "colonic muco-submucosal elongated polyps (CMSEP), which has been proposed by Matake et al. as a new clinical entity for unclassified colonic polyps. As endoscopic examination has become more widespread, CMSEP have increasingly been reported. However, there has been no report of CMSEP with varied forms of polyps at the same site. Thus, this case was thought to be very interesting with regard to the pathogenesis of CMSEP.