This article is more than 5 years old. Information may no longer be current.
Serrated polyp detection rate tied to post-colonoscopy cancer risk
Click Here to Manage Email Alerts
SAN ANTONIO — A higher serrated polyp detection rate was associated with a decreased incidence of post-colonoscopy colorectal cancer, according to study results presented at the American College of Gastroenterology Annual Meeting.
Joseph C. Anderson, MD, MHCDS, FACG, of White River Junction VA Medical Center in Vermont, said the serrated pathway may account for as much as 30% of CRC, but the link with serrated polyp detection rate (SDR) is unclear.
“We know that they’re difficult to detect because they have flat morphology and indistinct borders. These are their characteristics,” Anderson said in his presentation. “There is significant variation in published data with regard to [proximal] SDR, which is one of the rates that people will use. This spurred us to provide data to help guide recommendations for benchmark SDR.”
Researchers used data from the New Hampshire Colonoscopy Registry to determine if exams performed by endoscopists who have a clinically significant SDR of at least 7% reduced the incidence of post-colonoscopy CRC (PCCRC). They defined PCCRC as any CRC diagnoses between 6 and 36 months after a colonoscopy with an adenoma detected and between 6 and 60 months after a normal colonoscopy. They also defined clinically significant serrated polyps as any sessile serrated polyp, traditional serrated adenoma, serrate polyp at least 1 cm in size anywhere in the colon and any serrated polyp greater than 5 mm proximal to the sigmoid.
In the study group (n = 142,950), investigators found 75 CRCs diagnosed in the 6 to 60 months period following colonoscopy, including 45 diagnoses between 6 and 36 months. A clinically significant SDR of 7% had a similar hazard ratio (HR = 0.37; 95% CI, 0.17–0.83) compared with an adenoma detection rate of 25% (HR = 0.45; 95% CI, 0.23–.089).
Anderson said their findings show that a clinically significant SDR was associated with a decreased incidence of PCCRC.
“These data suggest that a [clinically significant] SDR of 7% or greater may be associated with lower PCCRC rates,” he concluded. – by Alex Young
Reference:
Anderson JC, et al. Abstract 23. Presented at: American College of Gastroenterology Annual Meeting; Oct. 25-30, 2019; San Antonio.
Disclosures: Anderson reports no relevant financial disclosures.
Perspective
Back to Top
This study tackles an issue that is important for endoscopists who perform screening and surveillance colonoscopies: preventing colorectal cancer and, specifically, interval colorectal cancers. Ideally, an individual should not develop colorectal cancer following a colonoscopy and prior to their next recommend colonoscopy. If they do, it is an interval cancer. The reality is that we do see interval colorectal cancers. Why is this happening? There are a multiple number of reasons, which include the biology of the tumors and the quality of the exam. This study targets both of these facts.
About one-third of colorectal cancers may arise from sessile serrated polyps. Due to their characteristics, they are difficult to spot. By focusing on the detection of sessile lesions, Anderson and colleagues have found a correlation between interval colorectal cancers and these biologically distinct lesions. Similarly, one would expect that endoscopists who are able to identify more of these lesions will have a lower rate of interval colorectal cancers. The adenoma detection rate is a validated quality metric for colonoscopy.
The higher the adenoma detection rate, the lower the risk for interval cancer. Based on this study, a clinically significant serrated detection rate of 7% correlated with an adenoma detection rate of 25%, providing framework for what a serrated detection rate should be. The serrated detection rate is important to follow, and it should be validated like the adenoma detection rate.
Read more about
Click Here to Manage Email Alerts