Strategies needed to increase follow-up colonoscopies after advanced adenoma removal
Surveillance colonoscopies completed within the U.S. Multi-Society Task Force recommended 3-year interval following the removal of high-risk adenomas appear underutilized and vary by patient age and health care system location, according to results of a population-based study.
“When a patient is found to have some of these higher-risk findings, guidelines recommend that they come back for another colonoscopy in 3 years,” Jessica Chubak, PhD, a senior investigator at Kaiser Permanente Washington Health Research Institute, said in a press release. “This is called surveillance colonoscopy, and it improves our chances of preventing colorectal cancer or detecting it at an early stage.”
Chubak and colleagues conducted a population-based study of patients aged 50 years to 89 years who received a colonoscopy between January 2010 and December 2010 at which time three adenomas and/or one adenoma with villous/tubulovillous histology were found.
The study, which was part of the NCI-funded Population-based Research Optimizing Screening through Personalized Regimens (PROSPR) consortium, included participants who were members of Kaiser Permanente Northern California, Kaiser Permanente Southern California, and Kaiser Permanente Washington, or had at least one primary care visit in the Parkland Health & Hospital System on or after January 1, 2010.
The researchers noted that the health systems differed from one another in screening, follow-up strategies and organizational structures. Additionally, information that was needed to identify other high-risk findings such as large adenoma, high-grade dysplasia, serrated lesions, or serrated polyposis syndrome were not consistently available, according to the researchers.
Patients were excluded from the study if they were lost to follow-up, received a diagnosis of colorectal cancer or received an additional colonoscopy with 6 months of their initial colonoscopy.
Researchers acknowledged that they excluded patients who received a second colonoscopy within 6 months of initial procedure because a short interval between colonoscopies could have been a result of an incomplete initial exam or unsatisfactory removal of polyp at the time of the initial colonoscopy.
Receipt of a subsequent colonoscopy between 6 months and 3.5 years after index colonoscopy procedure served as the primary endpoint.
Researchers identified 6,909 eligible patients (59.7% male; mean age, 64.1 years) based on their colonoscopy findings out of the 3,258,625 individuals in the PROSPR cohort.
More than half of patients (60.6%) had one to two villous/tubulovillous adenomas; 30.9% had three or more adenomas without villous/tubulovillous features; and 8.4% had three or more adenomas with at least one villous/tubulovillous adenoma.
Median follow-up was 3.41 years [interquartile range (IQR) = 3.12–3.70 years]. Among individuals without an observed subsequent colonoscopy, median follow-up was 3.30 years (IQR = 3.04–3.64 years).
The percentage of individuals who received a colonoscopy within 6 months to 3.5 years after their initial colonoscopy varied significantly by health care system location (P < .0001).
Less than 20% (18.3%; 95% CI, 11.7-27.8) of patients at Parkland received a subsequent colonoscopy within the recommended timeframe compared with 59.5% (95% CI, 53.8-65.2).
Time to subsequent colonoscopy differed by index colonoscopy findings (P < .0001).
Age at index was also associated with time to subsequent colonoscopy (P < .0001).
“The fact that a large proportion of patients with [three or more] adenomas or any adenoma with villous/tubulovillous features did not receive a subsequent colonoscopy within 3.5 years — even in health care systems with some procedures to support colonoscopy surveillance after high-risk adenomas — suggests a need for additional evidence-based interventions to improve adherence to surveillance guidelines,” the researchers wrote.
“We encourage patients and health care providers to talk about how and when to test for colorectal cancer, and we encourage health care systems to find ways to support patients and providers in following the guidelines,” Chubak said in the release. “In the future, it will be important to understand what types of reminders work best for different patient populations and in different health care settings.” – by Ryan McDonald
Disclosures: Chubak reports no relevant financial disclosures. Please see the full study for a list of all other authors’ relevant financial disclosures.