Objective  To analyze the results of colonoscopy screening on colorectal cancer among high risk individuals assessed from permanent residents of Shenzhen city during 2017 – 2019 for providing evidence to the optimization of strategies on the screening.

  Methods  Totally 6 2 60 permanent adult residents (aged 40 – 74 years) were assessed as having high risk of colorectal cancer based on the survey results of Major Cancer Early Diagnosis and Treatment Project in Urban Population conducted in Shenzhen city from May 2017 through August 2019. Of the high-risk individuals, 2 622 received colonoscopy examination and the data on 1 371 examinees with complete information of questionnaire interview and clinical examination were analyzed.

  Results  The compliance rate of colonoscopy examination was 41.88% for all the high-risk individuals identified in the project-based survey. Among the 1 371 colonoscopy examinees included in the analysis, the detection rate was 0.22% (3 cases) for colorectal cancer, 11.09% (152) for precancerous lesion, 34.50% (473) for benign polyps, 6.27% (86) for inflammatory bowel disease, 2.77% (38) for benign polyps combined with inflammatory lesion, and 10.80% (148) for other colorectal diseases, respectively. For the 1 371 examinees, the detection rate of precancerous lesions and benign polyps differed significantly by gender, age, body mass index, and salty food preference, while gender and salty food preference were also significantly related to the detection rate of other colon diseases (all P < 0.05); the detection rate of benign polyps combined with inflammatory lesion was influenced significantly by the frequency of fruit and meat consumption (both P < 0.05); and the detection rate of inflammatory bowel disease was significantly associated with tea drinking (P < 0.05).

  Conclusion  In urban Shenzhen, the compliance rate of colonoscopy examination is relatively high but the detection rate of various pathological lesions is low and influenced by multiple demographic and individual characteristics among the adult residents at high risk of colorectal cancer. The results suggest that both the scheme of colorectal cancer screening and the identification of high risk individuals need to be optimized for early diagnosis and treatment of the disease.