Analysis of efficacy and safety of colonoscopic screening program at the University of Szeged and the Bács-Kiskun County Teaching Hospital between 2019 and 2022

Introduction: The Hungarian population-based colorectal screening program was initiated in 2019 for asymptomatic individuals aged between 50 and 70, aiming to prevent the development of colorectal cancer. Objective: The study aimed to examine the quality indicators, outcome indicators, and safety of colonoscopies conducted at the University of Szeged and the Bacs-Kiskun County Teaching Hospital within the context of the screening program, aligning with Hungarian professional guidelines. Methods: In this non-intervention, observational cohort study, we utilized prospectively collected data from the National Public Health Center register, supplemented retrospectively with data from the hospital information system. Results: A total of 1,739 screening colonoscopies (mean age 62.36 +/- 5.86 years, male rate 56.81%) were performed with a cecum intubation rate of 97.07%. Bowel cleansing was adequate in 90.28% of cases, including excellent in 63.31% of cases. The withdrawal time was reported for 1397 complete colonoscopies, which exceeded the guideline recommended 6 minutes in 96.35% of cases, the mean duration was 9.51 +/- 5.76 minutes. Sedation was required for 40.37% of patients, of which 92.02% received midazolam. Colonoscopies found neoplastic lesions in 62.51% of cases, and in 27.03% of patients only non-neoplastic lesions were seen. A total of 2,879 polyps were found in 1,064 patients (polyp detection rate 61.18%), of which the size of the most relevant polyp exceeded 1 cm in 39.38% of the cases and 72.97% of them were located in the left colon. Index and complementary colonoscopy made 98.97% of patients polyp-free. Adenoma was confirmed in 871 patients, resulting in an adenoma detection rate of 50.09%. Colorectal carcinoma was detected in 80 patients (4.60%). Complications were seen in 10 patients (0.58%) and no intervention related deaths occurred. Clarifying gastroscopy was performed in 24.08% of the negative colonoscopies, which confirmed esophageal squamous cell carcinoma in 1 patient. In the follow-up period, 114 patients (6.56%) underwent repeated colonoscopy, with interval colorectal carcinoma in 1 patient (0.06%). Conclusion: The screening colonoscopies performed in the two centers included in the study met the quality and outcome indicators as well as patient safety criteria defined by the Hungarian guidelines. However, improvements are needed in data entry in the registry and the rate of clarifying gastroscopies following negative colonoscopies.