Relationship Between Bile Reflux And Gastric Cancer And Its Precancerous Lesions

Background: Gastric cancer(GC)is one of the most common malignancies in the world.According to Correa model,GC develops from chronic non-atropy gsatritis to chronic atrophy gastritis to intestinal metaplasia to dysplasia and finally in situ carcinoma.Intestinal metaplasia and dysplasia are the socalled precancerous lesions for gastric cancer.Helicobacter pylori(H.pylori)is the most important controllable risk factor for GC.H.pylori eradication can partially but not fully reduce the occurrence of GC,which indicates that other important risk factors are involved in the occurrence and development of GC.Bile reflux(BR)is closely related to the occurrence of upper gastrointestinal diseases such as upper gastrointestinal inflammation,intestinal metaplasia,and residual gastric cancer.However,it's unknown whether BR is related to GC and its precancerous lesions.Objective: The present study aimed to explore the relationship between BR and GC and its precancerous lesions,to determine whether BR is an independent risk factor for GC and its precancerous lesions,and to provide new ideas for GC prevention.Method: This study consists of two parts,on part is a retrospective study and another is a cross-section study.Retrospective Study: Totally 30465 patients who underwent general gastroscopy between January 2018 and December 2018 were selected.All the patients were documented with the ID number,sex,age,time of endoscopy,diagnosis and bile reflux grade.Patients were divided into the chronic gastritis group(n=27807),precancerous lesion group(n=1943),and GC group(n=715)according to diagnosis.The degree of BR under gastroscopy was classified as grade 0,I,II,or III.chi-squared and hierarchical analyses were used to statistically analyse the data.Cross-Sectional Study:Totally 1162 Patients who met the criteria for admission and required gastroscopy for consultation between June 15,2019 and October 1,2019 were enrolled.All patients underwent pathological biopsy and questionnaire filling,and were divided into chronic gastritis group(n=668),precancerous lesion group(n=411)and GC group(n=83)according to pathological results.BR classification is the same as retrospective study.The questionnaire results and diagnosis results were analyzed by single factor analysis and multiple logistic regression analysis.Result: Retrospective Study:(1)There were 6236 patients diagnosed withBR(20.46%).(2)Patients aged 18-27 years had a significantly higher BR detection rate than others in different age groups(p<0.000).(3)BR detection rate was not significantly different based on both months and seasons(p =0.240,p=0.213).(4)There was a significant difference between morning and afternoon rates(p<0.001).(5)The BR detection rates in chronic gastritis,precancerous lesions and GC were 18.4%,36.4% and57.3% respectively,and there were significant differences between any two groups regardless of sex,age and time slice(p <0.001).(6)There was an interrelationship between the severity of gastric mucosal disease and the BR grade(rs=0.171,p<0.001).Cross-sectional Study:(1)The chronic gastritis group and precancerous lesions group were combined together as control for analysing rish factors of GC.The univariate analysis showed that GC was related to sex,age,BMI,marital status,long-term residence,education,type of work,rest time,income,drinking water,acid reflux,heartburn,abdominal distension,appetite,vomiting,blood in the stool,high-salt diet,smoking,overnight dishes,pickled foods,pepper,fresh vegetable intake,tea drinking and BR(p<0.05).The multivariate analysis showed that BMI> 25,marriage(widowed),appetite,blood in the stool,pepper,tea and BR were independent risk factors of GC.(2)The chronic gastritis group was used as control for analysing rish factors of precancerous lesions.The univariate analysis showed that precancerous lesions were related to sex,age,education,type of work,rest time,drinking water,hiccups,nausea,vomiting,diarrhea,blood in the stool,family history of GC,coronary heart disease,history of H.pylori infection,overnight dishes,preserved food and BR(p <0.05).The multivariate analysis showed that sex,age,family history of GC,history of H.pylori infection and BR were independent risk factors of precancerous lesions.(3)BR had no relationship with GC family history and H.pylori infection history(p> 0.05).Conclusions: The detection rate and severity of BR gradually increase from chronic gastritis to precancerous lesions to GC.BR is an independent risk factor for the occurrence of GC and its precancerous lesions.These data suggest that BR could promote evoluation of gastric mucosal lesions and development of GC and that regulation of and blocking BR might be an important strategy for GC prevetion.