An Unusual Diagnosis of Rectosigmoid Leiomyoma in an Adult: A Rare Case Report.

Leiomyomas are uncommon tumors of the gastrointestinal system, representing around 0.03% to 0.05% of all rectal tumors. They tend to have a benign biological behavior and are mostly asymptomatic. When leiomyomas are large in size, they can cause symptoms and complications, including abdominal pain, perforation, intestinal obstruction, and bleeding. We herein present a case of a 57-year-old male patient presenting for colonoscopic evaluation following a positive screening with a fecal occult blood test. The patient was found to have a 10 mm pedunculated polyp at the level of the recto-sigmoid junction, which was removed by hot snare polypectomy and was found to have spindle cells that were positive for desmin, consistent with the rare diagnosis of recto-sigmoid leiomyoma. That being said, this case evokes a rare entity that endoscopists should keep in mind when approaching a recto-colonic polyp.