Prevalence of Serrated Polyposis Syndrome (SPS) in an Irish Colorectal Cancer (CRC) Screening Population

Aims SPS is associated with an increased risk of CRC, but is often under-recognised. SPS is diagnosed clinically based on the number, size and site of serrated polyps as defined by the World Health Organisation. Correctly identifying those with SPS is essential to allow endoscopic surveillance to be implemented. Our aim was to identify individuals undergoing colonoscopy as part of the Irish National CRC screening programme, BowelScreen, who fulfilled criteria for SPS and to determine if they had been recognised previously.

Methods A retrospective review of individuals who underwent a colonoscopy at one BowelScreen screening site between 2010 and 2015 was performed. Endoscopy and histology reports were used to identify the number, size, site and histology of polyps.

Results 1,992 individuals had a colonoscopy during the study period. 9.6% (n=192) had at least one serrated polyp. 2.6% (n=53) had 5 or more serrated polyps. 0.3% (n=6) fulfilled criteria for SPS. Only 1 (16.7%) individual had been recognised as having SPS previously. 83% of those with SPS met criteria based on the cumulative polyp count over multiple colonoscopies and would not have met criteria based on polyps found at a single colonoscopy.

Conclusions The prevalence of SPS in our screening population of 0.3% is similar to the prevalence demonstrated in other screening cohorts internationally. Under-recognition was evident with only one individual having been identified as having SPS previously. The importance of tracking cumulative polyp numbers and histology in those with more than one colonoscopy has also been highlighted given the majority of individuals only met criteria following polyps found at subsequent colonoscopies.

Publication History

Article published online:
14 April 2023