Analysis Of Pathological Features And Detection Related Factors Of Colorectal Flat Adenoma

Objective:Objective to analyze the clinicopathological features of colorectal flat adenoma and explore the independent influencing factors of flat adenoma detection,so as to improve the detection rate of colorectal flat adenoma and reduce the risk of colorectal cancer.Methods:the clinical and endoscopic data of patients who underwent colonoscopy in digestive endoscopy center of Affiliated Hospital of North Sichuan Medical College from July 2018 to November 2020 were retrospectively analyzed.According to the shape of adenoma,adenoma was divided into flat adenoma and protuberant adenoma;Objective to understand the clinicopathological features of flat adenoma by comparative analysis.According to whether flat adenoma was detected or not,the patients were divided into detection group and non detection group;By univariate analysis of the differences between the two groups in patient factors and colonoscopy related factors,the potential influencing factors of flat adenoma detection were screened,and these potential influencing factors were included in the multivariate logistic regression to analyze the independent risk factors of flat adenoma detection.Results:In this study,7998 patients were included,2550 adenomas were detected;Among them,396(18.5%)of patients with flat adenoma and 499(19.6%)of flat adenomas.In terms of the characteristics of adenoma,the proportion of flat adenoma and protuberant adenoma in the right hemicolon was 49.7%and 29.6%,respectively,the difference was statistically significant(χ2=73.104,P<0.001);The proportion of the two in the adenomas was 52.7%and 26.7%,respectively,the difference was statistically significant(χ2=129.760,P<0.001);The composition ratio of the two low-risk adenomas was 80%and 64.8%,respectively,the difference was statistically significant(χ2=41.955,P<0.001);In the right colon,the proportion of the two patients with advanced tumor change was 39.5%and 33.8%,respectively,the difference was statistically significant(χ2=7.735,P<0.05).In terms of influencing factors of flat adenoma detection,age>60 years old(or1.744,95%CI 1.337～2.273),history of adenoma(or3.793,95%CI 2.835～5.074),intestinal symptoms(or1.827,95%CI 1.438～2.322),sufficient intestinal cleaning(or4.223,95%CI 2.771～6.436),doctor’s experience≥ 1000 cases(or1.543,95%CI 1.215～1.960),and the time of endoscopy withdrawal ≥ 6min(or 1.587,95%CI 1.215～1.960),Flat adenoma was more likely to be detected in patients with rectal inversion(or 1.690,95%CI 1.315～2.170),NBI observation(or 1.312,95%CI 1.063～1.619),ascending colon inversion(or 2.188,95%CI 1.450～3.300)(P<0.05).Conclusion:Compared with the protuberant adenoma,the flat type adenoma is more common than the right half colon,and the small adenoma and low-risk adenoma with<5mm are more common.In the right half colon,the flat type adenoma is more likely to develop high-level intraepithelial tumor.In addition,age,history of adenoma,intestinal symptoms,quality of intestinal preparation,experience of doctors,time of retreat,imaging method and observation method were independent factors for detection of flat adenomas.This study can provide theoretical basis for endoscopic doctors to screen high-risk population of flat adenoma patients and identify flat adenomas.