Detection rates of proximal or large serrated polyps in Chinese patients undergoing screening colonoscopy

Objective: The aim was to determine the detection rates and characteristics of large or proximal serrated polyps in Chinese patients undergoing screening colonoscopy.

Methods: Consecutive screening colonoscopies performed between 2008 and 2011 were analyzed. Serrated polyps consisted of all hyperplastic polyps, sessile serrated adenomas and traditional serrated adenomas. Large serrated polyps were defined as serrated polyps with a diameter ≥ 10 mm. Lesions proximal to the descending colon were considered as proximal lesions. Advanced neoplasia included invasive adenocarcinomas, adenomas with high grade dysplasia, adenomas with any villous histology and tubular adenomas ≥ 10 mm.

Results: In total, 1282 colonoscopies were included. The detection rates for adenoma, advanced neoplasia, proximal serrated polyps and large serrated polyps were 26.1%, 10.5%, 7.2% and 2.3%, respectively. There was a significant association between synchronous advanced neoplasia and large serrated polyps (P = 0.002) or proximal serrated polyps (P = 0.013). Age ≥ 55 years (OR 1.9, 95% CI 1.2-2.8) and the presence of advanced neoplasia (OR 1.8, 95% CI 1.0-3.1) were significantly associated with the presence of large or proximal serrated polyps. Males had more advanced neoplasia (OR 2.0, 95% CI 1.4-2.9), but not more large or proximal serrated polyps, than females.

Conclusions: Large and proximal serrated polyps were detected in 2.3% and 7.2% of Chinese patients undergoing screening colonoscopies, respectively. Individuals with large or proximal serrated polyps have a higher risk of synchronous advanced neoplasia.