RISK OF COLORECTAL NEOPLASIA FOLLOWING COLONOSCOPIC RESECTION OF SESSILE SERRATED ADENOMA/POLYP

Aims:

The study was conducted to investigate the risk for colorectal neoplasia after colonoscopic resection of sessile serrated adenoma/polyps.

Methods:

Among the patients who underwent colonoscopy at the University of Korea Ansan Hospital between January 2012 and December 2015, total 147 patients with any serrated adenoma/polyp were enrolled in our study. Baseline characteristics and findings on initial and surveillance colonoscopy were extracted retrospectively. The incidence and risk factors of any colorectal neoplasia at the time of surveillance colonoscopy were evaluated.

Results:

In the 147 patients with any serrated adenoma/polyp, 3 (2%) with traditional serrated adenoma at index colonoscopy were excluded. Among 144 with sessile serrated adenoma/polyp (SSA/P), male was 89 (61.8%) and mean age was 57.1 year (range 21 – 85). At index colonoscopies of 144 patients, 166 SSA/P were resected and 266 other colorectal neoplasms such as tubular adenoma, tubulovillous adenoma, and cancer were detected. Among them, 30 (20.8%) patients underwent surveillance colonoscopy until September 2016. The mean interval between surveillance colonoscopy and initial colonoscopy was 19.6 months (range, 6.2 – 37.9 months). Cumulative incidence rate for any neoplasm on surveillance colonoscopy was 53.3% (n = 16), with a rate of 6.7% (n = 2) for advanced neoplasm. In univariate analysis between two groups according to the metachronous colorectal adenomas, the risk factor was not found, although male was more prevalent (61.9% vs. 33.3%, p = 0.151).

Conclusions:

The results reveal that SSA/P is associated with increased risk of metachronous colorectal neoplasm although significant risk factor of them is not found. Therefore, the short interval of surveillance colonoscopy can be considered in the patients with SSA/P on screening colonoscopy.