Diagnostic Yield and Miss Rate of EndoRings in an Organized Colorectal Cancer Screening Program: the SMART (Study Methodology for ADR-Related Technology) Trial

Abstract

Background and aims The add-on EndoRings has been claimed to improve adenoma detection at colonoscopy, but available data are inconsistent. When testing a new technology, parallel and crossover methodologies measure different outcomes, leaving uncertainty on their correspondence. Aims of this study were to compare the diagnostic yield and miss rate of the EndoRings for colorectal neoplasia. Methods Consecutive subjects undergoing colonoscopy after a positive fecal immunochemical test (FIT) within organized screening program in 7 Italian centers, were randomized between a parallel (EndoRings or Standard) or a crossover (EndoRings/Standard or Standard/EndoRings) methodology. Outcomes measures were the detection rates of (advanced) adenomas (A-)ADR in the parallel arms and miss rate of adenomas in the crossover arms. Results Of 958 eligible subjects, 927 (317 EndoRings; 317 Standard; 142 EndoRings/Standard; 151 Standard/Endorings) were included in the final analysis. In the parallel arms (mean ADR: 51.3%; mean AADR: 25.4%), no difference between Standard and EndoRings was found for both ADR (RR, 1.10; 95% CI, 0.95-1.28) and A-ADR (RR, 1.16; 95% CI, 0.88-1.51), as well as for the mean number of adenomas and advanced adenomas per patient (EndoRings: 1.9±1.3 and 1.0±1.2; Standard 2.1±1.5 and 1.0±1.2; p=NS for both comparisons). In the crossover arms, no difference in miss rate for adenomas between EndoRings and Standard was found at per-polyp (RR, 1.43; 95% CI, 0.97-2.10), as well as at per-patient analysis (24% vs 26%; p=0.76). Conclusions No statistically significant difference in diagnostic yield and miss rate between EndoRings and Standard colonoscopy was detected in FIT+ patients. A clinically relevant correspondence between miss and detection rates was shown, supporting a cause-effect relationship.