Screening for colorectal cancer in the Leningrad region: results of the introduction of immunochemical analysis of feces for occult blood and epidemiological trends

Introduction. Colorectal cancer (CRC) ranks second worldwide in prevalence and mortality among all malignancies. The implementation of screening programs based on fecal immunochemical testing (FIT) followed by colonoscopy is an effective strategy for reducing morbidity and mortality. In the Russian Federation, CRC screening is integrated into the clinical health examination of certain adult population groups. Aim. To assess the dynamics of colorectal cancer incidence and mortality in the Leningrad Region for the period 2015—2024, as well as the effectiveness of screening programs based on fecal immunochemical testing (FIT) and colonoscopy in the region for 2022—2025. Material and methods. A retrospective epidemiological analysis of official statistics data for the Leningradskaya Region, the Northwestern Federal District, and the Russian Federation was performed. Data from the annual reports «Malignant Neoplasms in Russia» edited by A.D. Kaprin and data from the Health Committee of the Leningrad Region for 2015—2025 were used. Incidence, mortality, stage distribution, FIT-testing coverage, number of colonoscopies, and active detection of CRC were analyzed. Results. During 2015—2024, a decrease in the incidence of colon cancer (average annual rate 24.11 vs 29.51 in Russia) and rectal cancer, rectosigmoid junction, and anal cancer (16.09 vs 20.9 in Russia) was observed in the Leningrad Region. CRC mortality decreased by 19.3% (colon cancer) and by 28% (rectal cancer). The proportion of stages III—IV decreased from 55% to 49%, while stage I detection increased from 6% to 17%. FIT-testing coverage increased from 12.6% to 30.0%, and the proportion of colonoscopies following positive FIT reached 70.0%. In 2025, 3.384 adenomatous polyps were detected. Active CRC detection in 2024 was 27%. Conclusion. CRC screening programs in the Leningrad Region have demonstrated effectiveness: increased detection of CRC and precancerous lesions is accompanied by improved stage distribution and reduced mortality. However, the active detection rate (27%) remains significantly below the target level (85%), indicating the need for further improvement in screening organization.