Endoscopic ultrasonography and submucosal resection in the diagnosis and treatment of rectal carcinoid tumors

Rectal carcinoid tumors are often diagnosed as .submucosal tumors on radiological or endoscopic examinations. Usually, its definite size and character, the infiltration of muscularis propria and vessels can not be correctly diagnosed preoperatively. In recent years, endoscopic ultrasonography （EUS） has been used in the diagnosis of submucosal tumors of the gastrointestinal tracts , Conventional endoscopic polypectomy allows local excision of local tumors, but is often associated with tumor involvement of the resection margin necessitates further interventions.