Detection rate of clinically significant serrated polyps in colorectal cancer screening: influencing factors and correlation with the adenoma detection rate

Aims The aims of our study were to determine the detection rate of clinically significant serrated polyps (CSSP), to explore its correlation with the adenoma detection rate (ADR), and to investigate the factors influencing the detection of CSSP [1].

Methods This retrospective study includes screening colonoscopies conducted on participants aged 50 years and older, over 18 months (from April 2022 to September 2023). Sessile serrated adenomas, traditional serrated adenomas, and hyperplastic polyps measuring at least 1 cm anywhere in the colon or more than 5 mm if located proximal to the sigmoid colon were considered clinically significant serrated polyps (CSSP)¹. Pathology reports were analyzed. Colonoscopies with poor bowel preparation assessed by the Boston Bowel Preparation Scale (BBPS) and incomplete procedures were excluded.

Results A total of 502 colonoscopies were included. The detection rate of CSSP was 3%, while the ADR was 42%. There was no statistically significant association between the detection of at least one adenoma per colonoscopy and the detection of at least one CSSP per colonoscopy (p>0.05). Furthermore, no correlation was observed between the number of adenomas per colonoscopy and the number of CSSP per colonoscopy (p>0.05). Male gender was significantly associated with the detection of at least one CSSP (Odds Ratio=2.5; 95% Confidence Interval; p<0.05). The mean withdrawal time differed significantly between patients with and without CSSP (14.2±8.2 vs 7.6±5.1 minutes; p<0.001), and there was a positive correlation between the mean withdrawal time and the total number of CSSP per colonoscopy (r=0.18; p=0.003). Factors such as age, Boston Bowel Preparation Scale (BBPS) score, schedule of colonoscopy, and endoscopist fatigue or experience were not associated with the CSSP detection rate (p>0.05).

Conclusions Despite achieving an adequate adenoma detection rate, the detection rate of CSSP in our cohort was lower than the benchmark suggested by the literature (3% versus 7%¹). The lack of association between these two indicators underscores the necessity to assess and enhance this quality metric to potentially reduce the incidence of CRC, and particularly the incidence of post- colonoscopy CRC. Additionally, male gender and longer mean withdrawal times were associated with an increased detection rate of CSSP, information that might help healthcare professionals optimize the detection of these particular colorectal cancer precursor lesions and improve related patient outcomes.

Publication History

Article published online:
27 March 2025

• References

• 1 Anderson JC, Butterly LF, Weiss JE. et al. Providing data for serrated polyp detection rate benchmarks: an analysis of the New Hampshire Colonoscopy Registry. Gastrointest Endosc 2017; 85: 1188-1194