Linked-color imaging (LCI) outperformed white-light (WL) colonoscopy in the detection of colon adenomas, according to cohort study data published in Gastrointestinal Endoscopy.
LCI is an imaging technology that highlights contrast in mucosal color. While prior studies suggest that LCI reduces polyp miss rate, its impact on adenoma detection rate has remained unclear. This multicenter, placebo-controlled, randomized clinical trial enrolled participants at 7 endoscopy sites around Italy. Eligible patients were aged 50-74 years and had returned a positive fecal immunochemical test (≥20 μg mercury [Hb]/g feces). Patients were randomized (1:1) to receive colonoscopy using either LCI or WL. Study endoscopists each had prior experience with LCI. Randomization was stratified by patient age, gender, and screening round. The primary outcome was adenoma detection rate (ADR), which was defined as the proportion of patients with at least 1 adenoma detected during colonoscopy. Secondary outcomes included advanced adenoma and sessile serrated lesion detection rates. Relative risk (RR) estimates for adenoma and ADR were calculated by study condition. Logistic regression was used to determine correlates of adenoma detection. Analyses were adjusted for relevant covariates, including age, sex, screening history, screening center, bowel preparation status, and procedure duration.
The total cohort comprised 649 patients: 326 randomized to LCI and 323 to WL. Mean age of the cohort was 60.8 ± 7.3 years, and 49.6% were men. Demographic and screening characteristics were comparable between study arms. The ADR in the LCI arm was 51.8%, compared with 43.7% in the WL arm (RR, 1.19; 95% CI, 1.01-1.40; P =.044). The detection rates for advanced adenomas (21.2% vs 18.9%; P =.53) and sessile serrated lesions (8.6% vs 5.9%; P =.23) were numerically—though not significantly—higher in the LCI arm. In per-polyp analyses, the mean number of adenomas per colonoscopy was comparable between study conditions. However, the number of proximal adenomas detected was higher with LCI compared with WL (0.72 ± 1.2 vs 0.55 ± 1.07; P =.05). In logistic regression models, patients who underwent LCI were significantly more likely to have any adenoma detected (OR, 1.53; 95% CI, 1.09-2.15). However, the odds of advanced adenoma detection were not significantly higher with LCI compared with WL (OR, 1.23; 95% CI, 0.85-1.80; P >.05).
Based on these results, routine use of LCI colonoscopy may improve adenoma detection in patients with a positive FIT.
As study limitations, investigators noted that endoscopists could not be blinded to each study condition, which may have introduced bias in favor of LCI. However, the ADR was also very high in the control arm and exceeded average detection rates observed at each clinic. As such, the risk for bias was likely low. “If further studies will confirm these data, such new artificial light may be expected to replace white-light for polyp detection, while reserving blue-based lights for characterization,” investigators wrote.
Disclosure: Several study authors declared affiliations with the manufacturer of the product tested in this study. Please see the original reference for a full list of authors’ disclosures.
Silvia P, Franco R, Carlo S, et al. Linked-color imaging versus white-light colonoscopy in an organized colorectal cancer screening program [published online June 2, 2020]. Gastrointest Endosc. doi: 10.1016/j.gie.2020.05.044