Management of recalcitrant colorectal adenoma with endoscopic mucosal resection.

In this report, we present a case of an atypical presentation with a solitary recalcitrant adenomatous colonic polyp, managed by endoscopic mucosal resection (EMR). The patient is a 17-year-old previously healthy male, who was evaluated by the gastroenterology clinic in the setting of abdominal pain, hematochezia and iron deficiency anemia. Patient was found to have a solitary rectosigmoid adenomatous polyp with low-grade dysplasia, and a normal upper endoscopy. The rectosigmoid polyp was difficult to completely resect via snare polypectomy and showed persistent regrowth, requiring EMR for complete resection. Of note, family history is extensive for malignancy, with patient's hereditary colorectal cancer genetic testing showing a heterozygous variant of unknown significance in one copy of his RNF43 gene. Follow-up endoscopic evaluation was unremarkable, with no polyp recurrence and negative pathology at the resected polyp site.