Use of a novel risk-adaptive screening modality synthesizing 5 risk factors for colorectal cancer (CRC) is associated with higher diagnostic yield than fecal immunochemical tests (FIT) in detecting advanced neoplasm, according to a study in the American Journal of Gastroenterology.
Findings were part of an interim analysis of baseline screening in the ongoing TARGET-C trial. Researchers from China randomized 19,546 participants (age range, 50-74 years) to received colonoscopy screening (n=3916), annual FIT (n=7854), or annual risk-adapted screening (n=7776).
Researchers used a modified version of the Asia-Pacific Colorectal Screening score for risk stratification in the risk-adaptive screening cohort. The score synthesizes risk factors for CRC, including age, sex, family history of CRC among first-degree relatives, smoking, and body mass index. A score ≥4 categorized a patient as high risk, whereas a score <4 defined low-risk patients. High- and low-risk patients were referred to either colonoscopy or FIT screening, respectively. Patients with positive FIT were referred for a diagnostic colonoscopy. The primary outcome of the study was detection rate of advanced neoplasm.
Higher participation rates were observed for patients undergoing FIT (94.0%) and risk-adapted screening (85.2%) compared with those undergoing colonoscopy (42.5%). The detection rate of advanced neoplasms during the intention-to-screen analysis was highest for those in the colonoscopy group (2.40%) and lowest for those in the FIT group 1.13%. The detection rate for the risk-adaptive approach was 1.66%. Corresponding odds ratios (ORs) were 2.16 (95% CI, 1.61-2.90; P <.001) for colonoscopy vs FIT, 1.49 (95% CI, 1.13-1.97; P <.001) for risk-adapted screening vs FIT, and 1.45 (1.10-1.90; P <.001) for colonoscopy vs risk-adapted screening.
The detection rate of advanced neoplasm among high-risk patients in the risk-adapted screening group was approximately 5.4%, which was significantly higher than the 2.4% detection rate observed in the colonoscopy group (OR, 1.72; 95% CI, 1.20-2.48; P =.004). A total of 18, 11, and 10 in the colonoscopy, risk-adapted screening, and FIT groups, respectively, required colonoscopy to detect at least 1 advanced neoplasm.
Limitations of the study included suboptimal compliance to diagnostic colonoscopy in FIT-positive participants, as well as the lack of long-term participation and diagnostic yield data.
The researchers concluded that “development of effective risk prediction models and design of suitable risk-adapted screening strategies” for CRC “are highly promising and deserve further attention in the era of precision medicine.”
Chen H, Lu M, Liu C, et al. Comparative evaluation of participation and diagnostic yield of colonoscopy vs fecal immunochemical test vs risk-adapted screening in colorectal cancer screening: Interim analysis of a multicenter randomized controlled trial (TARGET-C) [published online April 13, 2020]. Am J Gastroenterol. doi: 10.14309/ajg.0000000000000624