90th Annual Meeting Abstracts
A Move to the Right? The Viability of Alternatives to Colonoscopy
*Mark Y Sun, MD, *Samantha L Pugsley, BS, *Jessica P Simons, MD, Jennifer F. Tseng, MD, *Justin A Maykel, MD, *William B Sweeney, MD, *Karim Alavi, MD
University of Massachusetts Medical School, Worcester, MA
Purpose: In 1995, the US Preventative Services Task Force recommended commencing screening for colon cancer at age 50 for average-risk people; however, the type of screening method remains controversial. Alternatives to colonoscopy include flexible sigmoidoscopy, which does not evaluate the right colon, and CT colonography, which does not detect lesions <1 cm accurately. The aim of this study was to use a prospective database to determine whether flexible sigmoidoscopy and CT colonography would be viable alternatives to colonoscopy in the current era.
Methods: Using a prospective endoscopy database at a single academic medical center, 1964 consecutive adult patients having undergone a screening colonoscopy from 1/1/2007 - 10/19/2007 were identified. Basic demographic data along with polyp location, size and pathology were collected. Patients with a family history of colon cancer, previously documented polyps, or inflammatory bowel disease were excluded.
Results: Mean [±SD] age was 58.0±7.6 years; 49.9% were male. Polyps were present in 647 cases(32.9%), with adenomatous polyps accounting for 389 (62.5% of retrieved polyps). Of adenomatous polyps, 273 (70.2%) measured 0.1-0.49cm, 101 (26.0%) measured 0.5-0.99cm, 8 (2.0%) measured 1.0-1.49cm, and 7 (1.8%) measured >1.5cm. Right-sided (proximal to the splenic flexure) adenomas accounted for 192 (48.2%) cases. Of these, 186 (96.9%) polyps were <1 cm and the majority were tubular adenomas (93.6%).
Conclusion: Colonoscopy remains the most effective means of screening for colonic neoplasia. Flexible sigmoidoscopy appears insufficient as 48.2% of adenomatous lesions are found proximal to the splenic flexure. CT colonography would also have difficulty detecting the vast majority of adenomatous polyps as >96% of polyps measured less than 1cm and >70% of polyps measured less than 0.5cm.