Correlation Between Serrated Polyps And Synchronous Advanced Colorectal Neoplasia

Background and aimsColorectal cancer(CRC)develops from an accumulation of genetic and molecular changes arising within initially normal mucosa.Approximately 15–20%of all sporadic CRCs arise via the serrated pathway,in which serrated polyps may be the precursor lesions.Serrated polyps comprise a heterogeneous group of lesions with distinct histological and malignant features.These lesions are usually flat and sessile,occasionally covered by a mucous cap,and may be easily missed during colonoscopy screening.Serrated polyps are classified pathologically according to the World Health Organization criteria as hyperplastic polyps(HPs),sessile serrated adenoma/polyps(SSA/Ps)with or without cytological dysplasia,and traditional serrated adenomas(TSAs).However,the prevalence and distribution of serrated polyps are not initially well-defined.The frequency of serrated polyps may differ according to the characteristics of the cohort,such as demographics and ethnicity.It is important to determine the true prevalence and clinical significance of different subtypes of serrated polyps,and then we can estimate the actual cancer risk posed by these lesions and to develop appropriate screening and surveillance strategies.With development of the research,some colonoscopic studies have shown variable prevalence rates of these three subtypes of serrated polyps.Over the past few years,several studies have highlighted the association between serrated polyps and advanced colorectal neoplasia.Large serrated polyps(LSPs)were found to be strongly associated with synchronous cancer,and SSA/Ps have been shown to be associated with an increased risk of metachronous cancer.We aimed to identify independent risk factors for synchronous advanced neoplasia(AN),and determine the correlation between the endoscopic features of serrated polyps and synchronous AN.Materials and methodsWe retrospectively reviewed all individuals who underwent screening colonoscopy in Changzhou No.2 Hospital,Jiangsu,China,between January 2017 and July 2019.We collected the following clinical information from the hospital database:age,gender,BMI,triglyceride level,total cholesterol level,smoking history,drinking history,comorbidity,and medication history.We also recorded colonoscopic features such as the location,size,and number of polyps from the colonoscopy reports.All statistical analyses were conducted using SPSS v20.0.Continuous variables were expressed as mean and standard deviation,and analyzed using the Student t-test.Categorical variables were expressed as frequency and percentage,and analyzed using the Pearsonχ~2 test.Logistic regression analyses(univariable and multivariable)were used to identify risk factors for an.Variables that were significant(P<0.05)in the univariable analysis were entered into the multivariable analysis.The two-sidedχ~2 test or Fisher exact test set at P<0.05 was deemed statistically significant.ResultThe independent predictors of synchronous AN were HP(odds ratio[OR]:2.099,95%confidence interval[CI]:1.618–2.724,P<0.001),SSP(OR:3.131,95%CI:2.178–4.502;P<0.001),and age≥60 years(OR:1.939,95%CI:1.532–2.454,P<0.001).In the HP group,big polyps(except for proximal HPs)and polyps in both the proximal and distal colon(except for diminutive HPs)were associated with a high synchronous AN incidence(P<0.05).In the SSP group,multiple,proximal SSPs(P=0.025)and multiple,big SSPs(P=0.018)were associated with high synchronous AN rate.ConclusionsHP,SSP,and age≥60 years are independently associated with synchronous AN.When colonoscopy reveals HPs,especially big HPs and HPs in both the proximal and distal colon,or SSPs,especially multiple,proximal SSPs and multiple,big SSPs,we should pay close attention to the possibility of synchronous AN.