Abstract
BACKGROUND: This study aimed to evaluate the diagnostic yield of colonoscopy in asymptomatic individuals aged 45-49 years compared with those aged 50-54 years in a Turkish population, providing insights into region-specific screening strategies. METHODS: This retrospective multicenter study was conducted across three tertiary endoscopy units in Turkey. Screening colonoscopy data from 3943 asymptomatic individuals aged 45-54 years between 2018 and 2023 were analyzed. The patients were stratified into two groups: 45-49 years (Group 1) and 50-54 years (Group 2). Demographic characteristics, polyp size, histological features, and prevalence of early-onset advanced colorectal neoplasia (EAO-aCRN) were assessed. RESULTS: A total of 3943 patients were included, with 862 in Group 1 (45-49 years) and 3081 in Group 2 (50-54 years). The polyp detection rate was 16.6% in Group 1 and 22.9% in Group 2 (p < 0.001). The adenoma detection rates were 10.8% and 13.9% in Groups 1 and 2, respectively (p = 0.018). The advanced polyp detection rates were 3.2% and 7.3% in Groups 1 and 2, respectively (p < 0.001). Mean polyp size was 6.5 ± 5.1 mm in Group 1 and 8.8 ± 8.4 mm in Group 2 (p < 0.001). The mean number of polyps per patient was 1.5 ± 0.8 in Group 1 and 1.9 ± 1.6 in Group 2 (p = 0.023). Advanced neoplasia was detected in 16.6% of Group 1 patients compared with 22.9% of Group 2 patients (p < 0.001). CONCLUSIONS: While CRC screening at age 45 demonstrated lower detection rates of polyps and advanced neoplasia than at age 50, the higher prevalence of EAO-CRN among 45-49-year-olds in Turkey underscores the importance of early screening in high-risk populations. Tailored regional strategies incorporating individual risk factors are crucial for optimizing CRC prevention policies.