P4140 - Leiomyoma of the Ascending Colon: An Uncommon Lesion in an Uncommon Location

Joyce Lee, MD¹, Suzanne Elshafey, MD², Amir Soumekh, MD^2
1New York-Presbyterian / Weill Cornell Medical Center, Boston, MA; ²New York-Presbyterian Hospital/Weill Cornell Medical Center, New York, NY

Introduction: Leiomyomas are considered benign smooth muscle cell tumors that cause little to no symptoms. Colonic leiomyomas are rare, but are found incidentally during screening colonoscopies and are most common in the descending and sigmoid colon. This is a case that featured an asymptomatic muscularis mucosae leiomyoma resected from the ascending colon during a screening colonoscopy.

Case Description/Methods: A 54-year-old man with obesity, nephrolithiasis, and a calcified liver granuloma presented for a screening colonoscopy. The patient denied any symptoms, including abdominal pain, nausea, vomiting, melena, constipation, or diarrhea. Physical exam was negative for abnormal findings. Abdominal imaging from 2 years prior showed a nonspecific calcified granuloma of the liver, which had been monitored with interval imaging and laboratory studies. Screening colonoscopy revealed a 2 mm sessile polyp in the ascending colon, which was removed with a cold biopsy forceps. Resection and retrieval were complete. The specimen was sent for pathological analysis, which indicated muscularis mucosae leiomyoma. The patient was advised to repeat a colonoscopy in 5 years due to the presence of additional traditional adenomatous polyps.

Discussion: Colonic leiomyomas are typically benign and asymptomatic lesions that are found in greater frequency in individuals after the age of 60. They are reported to be most prevalent in the descending and sigmoid colon, with case studies also reporting the transverse colon. Although it is a rare and benign diagnosis, this case exhibits that colonic leiomyomas can manifest in areas as proximal as the ascending colon. The current recommended and most common treatment is endoscopic polypectomy, with limited observational evidence that up to 20% of polyps may recur. Given its rarity, there is no current evidence for evaluating their malignant potential, nor methods for endoscopically distinguishing them from other lesions, such as hyperplastic polyps. Hence, colonic leiomyomas are diagnosed based on histology. Additional reporting and studies are needed to better characterize the natural history of this disease and to form stronger evidence-based guidelines for management and surveillance of colonic leiomyomas.


Disclosures:


Joyce Lee, MD¹, Suzanne Elshafey, MD², Amir Soumekh, MD². P4140 - Leiomyoma of the Ascending Colon: An Uncommon Lesion in an Uncommon Location, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.