The U.S. Multi-Society Task Force on Colorectal Cancer (CRC) recently updated recommendations for patient follow-up after colonoscopy and polypectomy.
The new guidance was based on advancements in both research and technology since the last recommendations were published in 2012, reported lead author, of the University of California, San Diego, and colleagues.
“[Since 2012,] a number of articles have been published on risk of CRC based on colonoscopy findings and patient characteristics, as well as the potential impact of screening and surveillance colonoscopy on outcomes, such as incident CRC and polyps,” the investigators wrote in. “Further, recent studies increasingly reflect the modern era of colonoscopy with more awareness of the importance of quality factors (e.g., adequate bowel preparation, cecal intubation, adequate adenoma detection, and complete polyp resection), and utilization of state of the art technologies (e.g., high-deﬁnition colonoscopes).”
The task force identified key topics using PICO (patient, intervention, comparison, and outcome) questions before conducting a comprehensive literature review that included 136 articles. Based on these findings, two task force members generated recommendations that were further refined through consensus discussion.
According to Dr. Gupta and colleagues, some of the new recommendations, particularly those that advise less stringent follow-up, may encounter resistance from various stakeholders.
“Patients, primary care physicians, and colonoscopists may have concerns about lengthening a previously recommended interval, and will need to engage in shared decision making regarding whether to lengthen the follow-up interval based upon the guidance here or utilize the recommendation made at the time of the prior colonoscopy,” the task force wrote.
The most prominent recommendations of this kind concern patients who undergo removal of tubular adenomas less than 10 mm in size. For patients who have 1-2 of these adenomas removed, the task force now recommends follow-up after 7-10 years, instead of the previously recommended interval of 5-10 years.
“[This decision was] based on the growing body of evidence to support low risk for metachronous advanced neoplasia,” the task force wrote. “In this population, the risk for metachronous advanced neoplasia is similar to that for individuals with no adenoma. Importantly, the observed risk for fatal CRC among individuals with 1-10 adenomas less than 10 mm is lower than average for the general population.”
Along similar lines, patients who undergo removal of 3-4 small adenomas now have a recommended 3-5 year follow-up window, instead of the previously strict recommendation for follow-up at 3 years.
But not all of the new guidance is less stringent. While the task force previously recommended a follow-up period of less than 3 years after removal of more than 10 adenomas, they now recommend follow-up at 1 year. This change was made to simplify guidance, the investigators wrote, noting that the evidence base in this area “has not been markedly strengthened” since 2012.
Compared with the old guidance, the updated publication offers more detailed recommendations for follow-up after removal of serrated polyps. On this topic, 10 clinical scenarios are presented, with follow-up ranging from 6 months after piecemeal resection of a sessile serrated polyp greater than 20 mm to 10 years after removal of 20 or fewer hyperplastic polyps less than 10 mm that were located in the rectum or sigmoid colon. Incidentally, these two recommendations are strong and based on moderate evidence, whereas the remaining recommendations for serrated polyps are weak and based on very-low-quality evidence.
Because of such knowledge gaps, the investigators emphasized the need for more data. The publication includes extensive discussion of pressing research topics and appropriate methods of investigation.
“Our review highlights several opportunities for research to clarify risk stratification and management of patients post-polypectomy,” the task force wrote. “In order to optimize risk-reduction strategies, the mechanisms driving metachronous advanced neoplasia after baseline polypectomy and their relative frequency need to be better understood through studies that include large numbers of patients with interval cancers and/or advanced neoplasia after baseline polypectomy. Mechanisms may include new/incident growth, incomplete baseline resection, and missed neoplasia; each of these potential causes may require different interventions for improvement.”
The task force also suggested that some basic questions beyond risk stratification remain unanswered, such as the impact of surveillance on CRC incidence and mortality.
“Such evidence is needed given the increasing proportion of patients who are having adenomas detected as part of increased participation in CRC screening,” the task force wrote.
Other suggested topics of investigation include age-related analyses that incorporate procedural risk, cost-effectiveness studies, and comparisons of nonendoscopic methods of surveillance, such as fecal immunochemical testing.
The study was funded by the National Institutes of Health and the Department of Veterans Affairs. The investigators reported relationships with Covidien, Ironwood, Medtronic, and others.
SOURCE: Gupta S et al. Gastroenterology. 2020 Feb 7.