A Case of Giant Colonic Muco-submucosal Elongated Polyps Associated with Intussusception

Colonic muco-submucosal elongated polyp (CMSEP), a newly categorized non-neoplastic colorectal polyp, is a pedunculated and elongated polyp composed of normal mucosal and submucosal layers without any proper muscle layer. We herein report a giant variant of CMSEP associated with intussusception in the rectosigmoid colon, with a review of the literature. A 48-year-old woman underwent a laparoscopic low anterior resection due to multiple large submucosal polypoid masses associated with intussusception. Grossly, the colonic masses were multiple pedunculated polyps with a long stalk and branches ranging in size from a few millimeters to 14.0 cm in length. Microscopically, there was no evidence of hyperplasia, atypia, or active inflammation in the mucosa. The submucosal layers were composed of edematous and fibrotic stroma with fat tissue, dilated vessels, and lymphoid follicles.

Clinicopathological characteristic analysis of three cases of colonic muco-submucosal elongated polyp / 中华消化杂志

Objective To explore the clinicopathological features,diagnosis and differential diagnosis of colonic muco-submucosal elongated polyp (CMSEP).Methods The clinical manifestations,endoscopic and histological features of three cases of CMSEP were analyzed.The literature was reviewed with regard to the diagnostic criteria and differential diagnosis.Results Three patients were male,and aged 25,45 and 75 years old.Two polyps were at transverse colon and one at rectum.Under colonoscope,all three cases showed the long pedunculated polyps.The surfaces of two polyps were smooth and the colors were similar to colonic mucosa while one polyp appeared mucosal erosion and congestion on the top.Under optical microscope,three cases had similar lesions.The axis of the lesions was expanded submucosa and the surface was the layer of colonic mucosa.The expanded and thick walled blood vessels were seen paralleled to the long axis in the submucosa of the axis of lesions.One polyp with mucosal erosion on the top presented with adenocarcinomal changes.Conclusions CMSEP is a kind of specific polypoid lesion,with characteristic colonoscopic and pathological features.Most are benign changes,however malignant changes occur in a few cases.In histology,CMSEP should be identified with mucosal prolapse syndrome associated inflammatory polyp.