Impact of Adenoma Detection Rate on Prevalent Colorectal Cancer Identification in a National Colonoscopy Registry

The study investigated the impact of adenoma detection rate (ADR), a key quality metric for colonoscopy, on the identification of prevalent colorectal cancer (CRC) during colonoscopy. While ADR is known to inversely correlate with post-colonoscopy CRC, its association with detecting existing CRC at the time of the procedure was less clear. Using data from a large national colonoscopy registry, the researchers analyzed both screening colonoscopies and those conducted after abnormal fecal test results.

The primary aim was to assess the relationship between individual endoscopists' ADR and the likelihood of identifying CRC present during the procedure. Secondary analyses examined related quality indicators, such as detection of sessile serrated lesions and advanced precancerous lesions, while considering patient demographics, procedural factors, and endoscopist-specific variables.

The findings revealed a strong positive association between higher ADR and increased detection of prevalent CRC in both screening and follow-up colonoscopies. Endoscopists with lower ADRs consistently missed more cancers, regardless of their ability to detect sessile serrated lesions. Detection of advanced precancerous lesions also mirrored ADR patterns, suggesting overlapping skills in identifying adenomas and invasive cancers.

The study concluded that many post-colonoscopy CRCs might arise from cancers missed during the initial examination, not just from undetected precursor lesions progressing over time. These results underscore the importance of maintaining high ADRs and enhancing colonoscopy quality improvement initiatives. Improving ADR can lead to better recognition of early-stage cancers and subtle neoplastic lesions, ultimately reducing the burden of CRC.