Evaluation of recurrence and surgical complementation rates after endoscopic resection of large colorectal non-pedunculated lesions

Background and aim: the process that leads to the development of colorectal cancer takes many years and most tumors originate from polyps and non-polypoid lesions. Techniques of endoscopic resection are options to the surgical treatment, even in case of large lesions or with initial invasion. This study aimed to evaluate the recurrence and surgical complementation rates after endoscopic resection of large colorectal non-pedunculated lesions. Methods: a retrospective, longitudinal and descriptive trial was performed via an analysis of colonoscopies with the resection of non-pedunculated lesions larger than 3 cm, performed between 2014 and 2017. Results: sixty-two lesions were included from 61 patients and 32 (52.5 %) were female. The age ranged from 36 to 89 years, with a mean age of 60.5 years. Lesions had an average diameter of 40.08 mm, ranging from 30 to 80 mm. Regarding the location of the lesions, the most frequent colonic segments were the ascending and rectum, both accounting for 22.6 %. Considering the morphologic endoscopic classification, 67.7 % were granular laterally spreading tumors (LST), 38.8 % were homogeneous granular and 29 % were mixed granular. The most frequent histological types were tubulovillous adenoma (30.7 %) and intramucosal adenocarcinoma (29 %). The resection technique was piecemeal mucosectomy in 85.5 %. Five lesions were removed by en bloc mucosectomy, two (3.2 %) by endoscopic submucosal dissection (ESD) and two (3.2 %) by a hybrid technique. The recurrence rate was 25.8 %. Three patients needed complementary surgical treatment and the clinical success of endoscopic treatment was 95.1 %. Conclusion: recurrence rate after endoscopic resection of large colorectal lesions was 25.8 % and surgical complementation rate due to failure in the endoscopic treatment of recurrence was 4.8 %.