ORGANIZED COLORECTAL CANCER SCREENING IN HEALTHCARE WORKERS: POSITIVITY OF IMMUNOHISTOCHEMICAL AND IMMUNOCHROMATOGRAPHIC FECAL TESTS FOLLOWED BY COLONOSCOPY

Introduction Given the increasing incidence of colorectal cancer, prevention programs and strategies that include screening for occult blood in feces, either through quantitative fecal immunochemical testing (FIT) or qualitative immunochromatographic fecal testing (ICT), followed by colonoscopy, are being applied to detect lesions. FIT is an anti-globulin test with high specificity, while ICT can detect blood from the entire gastrointestinal tract.

Objective To evaluate the positivity rate of fecal tests and the adenoma detection rate (ADR) and colorectal cancer (CRC) detection rate in patients who tested positive.

Methods A cross-sectional, analytical, and single-center study. During the organized CRC screening of healthcare workers at a reference hospital in the Coloproctology service between April 2021 and June 2024, the positivity rates of FIT and ICT were evaluated. Patients with positive tests were referred for colonoscopy, and adenoma and CRC detection rates were assessed.

Results Of a total of 6679 healthcare workers aged 50 to 75 years, 4048 (56%) underwent testing, of which 230 (5.7%) were positive, indicating the need for colonoscopy. Using a cutoff value of 50 ng/mL, the positivity rate for FIT was 8%, and for ICT, it was 3%, a difference that could represent a significant loss of patients when using the qualitative test. Of the 230 positive individuals, 156 underwent colonoscopy (67.8%). Of these, 129 (82.7%) used FIT and 27 (17.3%) used ICT. The adenoma detection rate was 58.1% for FIT and 55.5% for ICT. In patients who underwent FIT, 6 serrated lesions, 75 adenomas (74 low-grade, 6 high-grade), and 4 neoplasms (1 neuroendocrine, 3 adenocarcinomas) were found. In patients who underwent ICT, 4 serrated lesions, 16 adenomas (15 low-grade, 1 high-grade), and no neoplasms were found.

Conclusion 1. The results showed higher positivity for FIT compared to ICT. 2. The adenoma detection rate was similar for both tests. 3. Despite the difference in the number of tests, CRC was diagnosed only in the FIT group. 4. In an asymptomatic, average-risk population, occult blood testing followed by colonoscopy is an essential strategy for diagnosing precursor and advanced colorectal lesions.

Publikationsverlauf

Artikel online veröffentlicht:
25. April 2025