Colorectal cancer starts in the colon or the rectum and is termed accordingly, based on the location. Early cases of colorectal cancer can begin as non-cancerous polyps, which are generally asymptomatic but detected by screening. Therefore, doctors recommend screenings for people at high risk or aged over 50 years. Colorectal cancer symptoms depend on the size and location of cancer. Some commonly experienced symptoms include changes in bowel habits, changes in stool consistency, blood in the stool, and abdominal discomfort. Common treatments for colorectal cancer include surgery to remove cancer, chemotherapy, and radiation therapy.

The adenoma detection rate (ADR) is directly related to colorectal cancer (CRC) incidence and mortality. ADR is a well-established quality indicator for colonoscopy and is inversely associated with the incidence of interval post-colonoscopy colorectal cancer. However, interval post-colonoscopy colorectal cancers, which generally develop from serrated polyps, are not included in the ADR. Therefore, the proximal serrated polyp detection rate (PSPDR) has been proposed as a quality indicator. The ADR is defined as the proportion of all colonoscopies in which at least one conventional adenoma is detected; and PSPDR is the proportion of colonoscopies wherein at least one serrated polyp proximal to the descending colon is detected, confirmed by histopathology.

This study aims to evaluate the association of the proximal serrated polyp detection rate (PSPDR) with interval post-colonoscopy colorectal based on data collected in the Dutch colorectal cancer screening program.

In this population-based data analysis, the association between endoscopists′ PSPDR and their patients′ risk of interval post-colonoscopy colorectal cancer was investigated and evaluated. Participants in the screening program were asymptomatic, aged between 55 to 76 years, had a positive fecal immunochemical test and underwent a colonoscopy. Detection rates were determined for each endoscopist individually. Additionally, the risk of interval post-colonoscopy colorectal cancer for endoscopists with a PSPDR and ADR, above the median versus endoscopists, with either one or both parameters, below the median was also evaluated.

The results and outcome of the study interpreted that the PSPDR of an endoscopist is inversely associated with the incidence of interval post-colonoscopy colorectal cancer. Thus, it can be concluded that the implementation of PSPDR monitoring, in addition to ADR monitoring, could optimize colorectal cancer prevention.

Keywords: Colorectal Cancer; Serrated Polyp; Colonoscopy; Adenoma Detection Rate (ADR); Proximal Serrated Polyp Detection Rate (PSPDR)

Source –David E F W M van Toledo  1 , Joep E G IJspeert  1 , Patrick M Bossuyt  2 , et al.; Serrated polyp detection and risk of interval; Lancet Gastroenterol Hepatol. 2022 Aug;7(8):747-754.