Colonoscopy outreach increased CRC screening more than FIT outreach; both were better than usual care

Those choosing screening tests may need to start considering the feasibility of achieving all related downstream actions as well as sensitivity, false-positive rates, safety, and cost, an ACP Journal Club commentary said.


In a recent pragmatic randomized clinical trial, 5,999 participants ages 50 to 64 years who were receiving primary care and were not up to date with colorectal cancer (CRC) screenings were randomly assigned to mailed outreach for the fecal immunochemical test (FIT), mailed outreach for colonoscopy, or usual care with clinic-based screening. Patients who received colonoscopy or FIT outreach invitations were more likely than those receiving usual care to complete CRC screening process within three years (38.4%, 28.0%, and 10.7%, respectively), with no screening-related harms noted in any groups.

The article was published Sept. 5, 2017, by JAMA. The following commentary by Robert H. Fletcher, MD, MSc, MACP, appeared in the ACP Journal Club section of the Dec. 19, 2017, Annals of Internal Medicine.

Efforts to increase CRC screening are often considered successful once patients have completed a test. But the benefits of screening depend on completion of a series of actions—screening, periodic rescreening, follow-up of positive screening results with diagnostic colonoscopy, and removal of adenomas and cancers found. These steps, from beginning to end, must be completed for the patient to benefit from having begun screening.

Singal and colleagues evaluated outreach interventions intended to achieve completion of this chain of actions for 2 commonly used tests—colonoscopy and FIT. Other studies of outreach generally consider a single test or step in the screening process.

Although screening rates in the first year were lower for colonoscopy than FIT, completion of the screening process over 3 years was higher for colonoscopy due to a reduction over time in the completion of all aspects of FIT screening. Of patients offered FIT, 70% were screened in the first year, most with FIT, but only 31% who had negative results completed 3 FITs in 3 years. These results make sense because it is easier to keep up to date with colonoscopy over time, since 1 test simultaneously achieves screening and diagnosis and is good for 10 years, whereas FIT must be done yearly, with additional testing if results are positive. FIT completion rates were low at each step: Only 33% of patients with positive results on screening FIT had colonoscopy. Even in highly regarded integrated systems, follow-up of positive FIT results needs improvement.

When screening tests are being chosen, perhaps the feasibility of achieving all downstream actions related to screening, in addition to sensitivity, false-positive rates, safety, and cost, should be considered. This would add another reason to choose colonoscopy, despite its up-front cost, small risk, and 1-time inconvenience. However, this may not be possible in all health systems or all patients with such barriers as limited endoscopic capacity, transportation, or co-payments. Those who choose to screen with FIT should pay as much attention to finishing the sequence as they do to starting it.