Large colorectal polyps: endoscopic management and rate of malignancy: does size matter?

High rate of malignancy has been reported in large colorectal polyps. However, studies were limited by including surgically resected polypoid lesions, only polyp ≥3 cm, only sessile polyps or carcinoma in situ. The aim of the study was to define the prevalence of invasive carcinoma among colorectal polyps ≥2 cm in diameter detected by colonoscopy and also to study the success of endoscopic resection.

All polypectomies of ≥2 cm colorectal polyps were identified from our endoscopy and pathology database and patients' medical records were reviewed for gross features, techniques of resection, complications, histology, and follow-up. Standard statistical tests were applied for calculating the rates, prevalence, and difference in proportions.

Colonoscopic resection of 183 large polyps was performed in 174 patients over a period of 6 years (55% men and 45% women), mean age 64 years (median 67 y and range 25-91 y). The majority of polyps were sessile (84%). Fifty-six percent were located in the right colon. Invasive cancer was found in 10% of polyps. Endoscopic resection was successful in 89% of patients. Postpolypectomy bleeding and perforation was noted in 5% and 2% of patients, respectively. No death was observed. Seventy-eight percent of patients completed >1 year of follow-up after initial polypectomy. Recurrence of adenoma was noted in 12%, which was managed successfully by colonoscopic polypectomy techniques.

The rate of invasive cancer is low among endoscopically resected large colorectal polyps and most of these polyps can be resected successfully via colonoscopy with minimal morbidity and no mortality. A close endoscopic follow-up is required to monitor for recurrence.