Summary. Rectal leiomyomas are a rare conditions, with low reported incidence in literature and constitute
about 0.1% of rectal tumours; in fact rectal leiomyomas occur in approximately 1 out of 2000-3000 rectal
tumors. We report on a patient with a 3 cm semi-pedunculated colonic leiomyoma, which was successfully
removed by endoscopic polypectomy after normal saline-epinephrine submucosal injection. When we encounter
a tumor during a colonoscopic examination, we usually evaluate the tumor carefully and perform an
endoscopic resection when we judge it is appropriate. When a symptomatic smooth muscle tumors smaller
than 2 cm are incidentally found on colonoscopy, surgical resection is unnecessary. Furthermore, if a tumor
can be lifted with a snare and it is either pedunculated or semi-pedunculated, endoscopic resection might be a
safe option. For those tumors with wide-based or exoluminal growth, endoscopic removal should be avoided
due to the higher risks of bleeding and perforation. The histological findings of the resected tumor are important.
If there is any malignant element that can not be completely eradicated, we would suggest surgical
treatment. We believe our process allows to avoid unnecessary surgery and reduces medical costs