S3373 Endoscopic Mucosal Resection of a Lateral Spreading Tumors Descending Colon

Abstract

INTRODUCTION: Lateral spreading tumors (LST) are nonpolypoid lesions larger than 10 mm in width that extend laterally and circumferentially rather than vertically. These lesions have the potential for malignant transformation. Therefore, complete resection is recommended. However, given the fact that these lesions most of the time are flat in morphology and have large dimensions, complete resection using simple methods such as snare polypectomy is challenging. Endoscopic Mucosal Resection (EMR) and endoscopic mucosal dissection (ESD) are minimally invasive resection techniques that can be used to resect LST completely. Nonetheless, careful examination and evaluation of LST using high-quality images such as narrowband imaging (NBI) and Chromoendoscopy are important before performing EMR or ESD. Here, we present a case of large LST that was nicely demarcated using Chromoendoscopy. CASE DESCRIPTION/METHODS: A 71-year-old Caucasian male with multiple comorbidities who initially presented for colon cancer screening. LST greater than 2 cm in size and involving multiple folds was found. The lesion was encompassing >50% of mucosal surface of the descending colon. The polyp was carefully examined with narrowband imaging (NBI) and Chromoendoscopy (indigo carmine was sprayed on top of the lesion and subsequently crystal violet). The lesion met Paris classification 0–2A and Kudo pit pattern 3L. ORISE gel was injected to create a submucosal pillow at the base of this polyp and the polyp lifted well. The polyp was then completely resected via EMR. A small residual defect was seen but no closure was required. Histopathology report showed hyperplastic polyp. A follow-up colonoscopy was performed few months later. The resection site was notable for significant scarring and narrowing of the colonic lumen. The mucosa appeared pale with slightly larger pits, and irregular sparse vessels. However, there was no evidence of recurrent adenoma at the resection site upon evaluation by NBI and Chromoendoscpy. Biopsies were taken from the base of the resection site. Final histopathology report from the resection site showed tubular adenoma with low grade dysplasia. DISCUSSION: Careful examination and evaluation of LST by using chromoendoscopy and NBI are crucial before performing EMR or ESD safely and effectively.