miRNA polymorphisms and risk of gastric cancer in Asian population

miRNAs are endogenous 19-to 25-nt noncoding RNAs that can negatively regulate gene expression by directly cleaving target mRNA or by inhibiting its translation.Recent studies have revealed that miRNA plays a significant role in gastric cancer development either as a tumor suppressor gene or oncogene.miRNA-singlenucleotide polymorphisms(SNPs),as a novel class of functional SNPs/polymorphisms,have been identified as candidate biomarkers for gastric cancer susceptibility.On the basis of recent data,the present review summarizes current knowledge of the functional effects of miRNA-SNPs and their importance as candidate gastric cancer biomarkers.Additionally,this review also includes a meta-analysis of the most frequently studied miRNA-SNPs in gastric cancer.

Risk Factors of Precancerous Gastric Lesions in A Population at High Risk of Gastric Cancer

Objective： In cancer prevention, the targeting of precancerous lesions has been recognized as the most promising method. However, little attention has been paid to the risk factors of precancerous gastric lesions, especially in rural China where there is high prevalence of precancerous gastric lesions. We therefore conducted a cross-sectional study in Liaoning province, China, to investigate the potential risk and protective factors of these precancerous gastric lesions. Methods： A total of 1,179 subjects with high risk of gastric cancer from Zhuanghe County were included in this study. Standard questionnaires were used in collecting epidemiological factors and the data were then analyzed by the unconditional logistic regression model. Results： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects, and the association of smoking or drinking and the precancerous gastric lesions increased in strength with the daily consumption and duration. As the factors such as age, gender, smoking, alcohol were controlled, a multivariable analysis revealed that there was a significant correlation between the deep-fry food intake and the gastric epithelial dysplasia with the odds ratio （OR） of 1.78 [95% confidence interval （CI）： 1.01-3.12]. Garlic eating was shown to confer protection against the development of gastric ulcer （OR=0.55, 95% CI： 0.33-0.92）. Conclusion： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects. Deep-fry food intake might be one of the risk factors for the precancerous gastric lesions and garlic eating was shown to confer protection against the development of gastric ulcer among rural Chinese population.

Pre-existing diabetes mellitus increases the risk of gastric cancer:A meta-analysis

AIM:To systematically assess the association between diabetes and incidence of gastric cancer.METHODS:We searched MedLine (PubMed),EMBASE,and the Cochrane Library without any limitations with respect to publication date or language,we also searched the references of qualifying articles.Casecontrol studies and cohort studies comparing the risk of gastric cancer between diabetic patients and control subjects were included.We excluded studies reporting only standardized incidence ratios without control groups and those that investigated only mortality but not incidence.Seventeen studies met our criteria,and the qualities of these studies were assessed using theNewcastle-Ottawa Quality Assessment Scale.We performed a meta-analysis of pre-existing diabetes and gastric cancer incidence using the DerSimonian-Laird method for random-effects.For subgroup analyses,we separated the studies by study type,region,sex and method to determine confounding factors and reliability.We also conducted subgroup analyses to examine the effects of smoking,Helicobacter pylori (H.pylori) infection,and cancer site.Publication bias was evaluated using Begg's test.RESULTS:A random-effects model meta-analysis showed an increased gastric cancer risk in diabetic patients [relative risk (RR)=1.19;95%CI:1.08-1.31].Subgroup analyses indicated that this result persisted in cohort studies (RR=1.20;95%CI:1.08-1.34),in studies on populations of both Western (RR=1.18;95%CI:1.03-1.36) and Eastern countries (RR=1.19;95%CI:1.02-1.38),in a female subgroup (RR=1.24;95%CI:1.01-1.52),and in highly qualified studies (RR=1.17;95%CI:1.05-1.31).Moreover,these results persisted when the analysis was confined to studies adjusted for well-known gastric cancer risk factors such as smoking (RR=1.17;95%CI:1.01-1.34) and H.pylori infection (RR=2.35;95%CI:1.24-4.46).CONCLUSION:Pre-existing diabetes mellitus may increase the risk of gastric cancer by approximately 19%.This effect seems to be unrelated to geographical region.

Study of risk factors for gastric cancer by populational databases analysis

AIM:To study the association between the incidence of gastric cancer and populational exposure to risk/protective factors through an analysis of international databases.METHODS:Open-access global databases concerning the incidence of gastric cancer and its risk/protective factors were identified through an extensive search on the Web.As its distribution was neither normal nor symmetric,the cancer incidence of each country was categorized according to ranges of percentile distribution.The association of each risk/protective factor with exposure was measured between the extreme ranges of the incidence of gastric cancer(under the 25th percentile and above the 75th percentile)by the use of the Mann-Whitney test,considering a significance level of0.05.RESULTS:A variable amount of data omission was observed among all of the factors under study.A weak or nonexistent correlation between the incidence of gastric cancer and the study variables was shown by a visual analysis of scatterplot dispersion.In contrast,an analysis of categorized incidence revealed that the countries with the highest human development index(HDI)values had the highest rates of obesity in males and the highest consumption of alcohol,tobacco,fruits,vegetables and meat,which were associated with higher incidences of gastric cancer.There was no significant difference for the risk factors of obesity in females and fish consumption.CONCLUSION:Higher HDI values,coupled with a higher prevalence of male obesity and a higher per capita consumption of alcohol,tobacco,fruits,vegetables and meat,are associated with a higher incidence of gastric cancer based on an analysis of populational global data.

Novel risk markers for gastric cancer screening: Present status and future prospects

Initial identification of populations at high risk of gastric cancer (GC) is important for endoscopic screening of GC. As serum pepsinogen (PG) test-positive subjects with progression of chronic atrophic gastritis (CAG) show a high likelihood of future cancer development, this population warrants careful follow-up observation as a high-risk GC group. By combining the PG test with Helicobacter pylori (HP) antibody titers, the HP-related chronic gastritis stage can be classified, thus identifying not only a GC high-risk group but also a low-risk group. Among PG test-negative patients without CAG, those with high serum PG Ⅱ levels and HP antibody titers are thought to have severe gastric mucosal inflammation and the risk of diffuse-type GC is also high. Meanwhile, in gastric mucosae obtained by endoscopic biopsy, HP infection induces aberrant DNA methylation in CpG islands in multiple gene regions and the extent of methylation clearly correlates with GC risk. By quantifying aberrant DNA methylation in suitable gene markers, we can determine the extent of the epigenetic field for cancerization. These novel concepts and risk markers will have many clinical applications in gastrointestinal endoscopy, including more efficient endoscopic GC screening and a strategic approach to metachronous multiple GCs after endoscopic treatment.

MUTAGENICITY AND CARCINOGENICITY OF FISH SAUCE FROM A COUNTY WITH THE HIGH RISK FOR GASTRIC CANCER IN CHINA

The mutagenicity and carcinogenicity of fish sauce (FS) sample from Changle County, a high gastric cancer mortality (113.20/105) area, were investigated with the biologic short-term tests and laboratory animal experiment. The results showed that the extract of FS was markedly direct mutagenic toward S. typhimurium TA100, induced high sister chromatid exchanges (SCE) and micronucleus (MN) in V79 cells after nitrosation with sodium nitrite. But the non-nitrosated FS did not. The nitrosated fish sauce (NFS) also induced SOS in E. coli PQ37 and alkylation of calfthymus DNA. The potency of NFS to induce unscheduled DNA synthesis (UDS) in human normal gastric mucosal cells was increased about fivefold compared with FS. When the NFS extract was given to newborn rats by gavage, dys-plasia and adenocaroinoma were induced in the glandular stomach in the 4th and 16th experimental week, respectively. N-nitrosamides were also found in NFS, which may account for the mutagenicity and carcinogenicity of NFS. It is indicated that FS, a traditional daily eaten seasoning, may contribute to the causes of the high gastric cancer mortality for the local residents.

MiR-146a rs2910164 polymorphism increases risk of gastric cancer:A meta-analysis

AIM: To systematically evaluate the association between the miR-146a rs2910164 polymorphism and susceptibility to gastric cancer.

Risk factors for tuberculosis after gastrectomy in gastric cancer

AIM: To examine incidence of tuberculosis(TB) in gastrectomy patients and investigate the risk factors for developing TB after gastrectomy in patients with gastric cancer.METHODS: A retrospective cohort study of gastrectomy patients with gastric cancer was performed at a university-affiliated hospital in Seoul, South Korea between January 2007 and December 2009. We reviewed patient medical records and collected data associated with the risk of TB, surgery, and gastric cancer. Standardized incidence ratios(SIRs) of TB were calculated to compare the incidence of TB in gastrectomy patients with that in the general Korean population, and risk factors for TB after gastrectomies were analyzed.RESULTS: Among the 1776 gastrectomy patients, 0.9%(16/1776) developed post-gastrectomy TB, with an incidence of 223.7 cases per 100000 patients per year. The overall incidence of TB in gastrectomy patients, adjusted by sex and age, was significantly higher thanthat in the general population(SIR = 2.22, 95%CI: 1.27-3.60). Previous TB infection [odds ratio(OR) = 7.1, P < 0.001], lower body mass index(BMI)(kg/m2; OR = 1.21, P = 0.043) and gastrectomy extent(total gastrectomy vs subtotal gastrectomy)(OR = 3.48, P = 0.017) were significant risk factors for TB after gastrectomy in a multivariate analysis.CONCLUSION: TB incidence after gastrectomy is higher than that in the general population. Previous TB infection, lower BMI, and total gastrectomy are risk factors for TB after gastrectomy in patients with gastric cancer.

Risk-stratification model to select conversion surgery for advanced gastric cancer patients

Objective: Conversion surgery is a surgery with a purpose of R0 resection in primary advanced gastric cancer(GC) that responded well to systemic chemotherapy. This study aimed to explore the efficacy of conversion surgery for advanced GC.Methods: A total of 618 advanced GC patients receiving systemic chemotherapy were stratified into low-,moderate-and high-risk groups based on a nomogram-predicted probability of overall survival. The survival of conversion surgery and chemotherapy alone groups was compared using the log-rank test and Cox regression analysis after propensity score matching(PSM).Results: A nomogram with good discrimination(concordance index: 0.65) and accurate calibration was constructed. After PSM, the median survival time(MST) of conversion surgery was 26.80 months, compared with16.60 months of chemotherapy alone(P<0.001). Conversion surgery was associated with a longer MST for patients in the low-risk group(30.40 months vs. 20.90 months, P=0.013), whereas it was not associated with prolonged survival in the moderate-and high-risk groups(P=0.221 and P=0.131, respectively).Conclusions: Conversion surgery was associated with longer survival, especially for low-risk population.

Pathogenetic mechanisms in gastric cancer

Gastric cancer(GC) is a major public health issue as the fourth most common cancer and the second leading cause of cancer-related death. Recent advances have improved our understanding of its molecular pathogenesis,as best exemplified by elucidating the fundamental role of several major signaling pathways and related molecular derangements. Central to these mechanisms are the genetic and epigenetic alterations in these signaling pathways,such as gene mutations,copy number variants,aberrant gene methylation and histone modification,nucleosome positioning,and microRNAs. Some of these genetic/epigenetic alterations represent effective diagnostic and prognostic biomarkers and therapeutic targets for GC. This information has now opened unprecedented opportunities for better understanding of the molecular mechanisms of gastric carcinogenesis and the development of novel therapeutic strategies for this cancer. The pathogenetic mechanisms of GC are the focus of this review.

Analysis of demographic characteristics in 3242 young age gastric cancer patients in Korea

AIM:To evaluate the epidemiologic features of young age gastric cancer(GC). METHODS:Retrospectively,a total of 3242 patients with GC between 18 and 45 years of age and 3000 sex-and age-matched controls were reviewed.All subjects were stratified into 3 groups based on age (A,18-30 years;B,31-40 years;C,41-45 years). Epidemiologic characteristics and risk factors were investigated with reference to their age and gender. RESULTS:Compared to controls,more frequent intake of high risk diet(P=0.00075),history of heavy smoking(P=0.00087),intake of heavy alcohol(P= 0.00091),lower social economic status(P=0.00083), body mass index>30(P=0.00097),urban residence(P=0.00065),and more frequent exposure to harmful occupational environments(P=0.00072)were observed in all age groups and both genders in young age GC.These relationships were weaker in females compared to males of the same age,and were stronger as the age of patients increased.However,in group C of young age GC patients,environmental factors played important roles in females and males with a similar body weight.In females,older age at first delivery(> 35 years),lack of lactation history,nulliparity,and poor nutritional status during pregnancy were significantly associated with an increased risk of GC(P=0.00034). In this study,252 patients(7.8%)had a family history of GC with high odds ratio(OR)(3.22-4.21).In particular, family history was more closely associated with GC in males(OR,4.21 in male vs 3.46 in female)and more advanced cases(P=0.00051). CONCLUSION:Hormonal associated factors were more commonly associated with females whereas environmental factors were more commonly associated with males in young age GC patients.

Improving the outcomes in gastric cancer surgery

Gastric cancer remains a significant health problem worldwide and surgery is currently the only potentially curative treatment option. Gastric cancer surgery is generally considered to be high risk surgery and fiveyear survival rates are poor,therefore a continuous strive to improve outcomes for these patients is warranted. Fortunately,in the last decades several potential advances have been introduced that intervene at various stages of the treatment process. This review provides an overview of methods implemented in pre-,intra- and postoperative stage of gastric cancer surgery to improve outcome. Better preoperative risk assessment using comorbidity index(e.g.,Charlson comorbidity index),assessment of nutritional status(e.g.,short nutritional assessment questionnaire,nutritional risk screening- 2002) and frailty assessment(Groningen frailty indicator,Edmonton frail scale,Hopkins frailty) was introduced. Also preoperative optimization of patients using prehabilitation has future potential.Implementation of fast-track or enhanced recovery after surgery programs is showing promising results,although future studies have to determine what the exact optimal strategy is.Introduction of laparoscopic surgery has shown improvement of results as well as optimization of lymph node dissection.Hyperthermic intraperitoneal chemotherapy has not shown to be beneficial in peritoneal metastatic disease thus far.Advances in postoperative care include optimal timing of oral diet,which has been shown to reduce hospital stay.In general,hospital volume,i.e.,centralization,and clinical audits might further improve the outcome in gastric cancer surgery.In conclusion,progress has been made in improving the surgical treatment of gastric cancer.However,gastric cancer treatment is high risk surgery and many areas for future research remain.

Lethal-7-related polymorphisms are associated with susceptibility to and prognosis of gastric cancer

BACKGROUND The lethal-7(let-7)family members and their targets are involved in the development and progression of tumors.Let-7-related polymorphisms have been reported to be associated with tumorigenesis and prognosis.In gastric cancer,however,the related studies are limited.AIM To investigate the role of let-7-related microRNA polymorphisms in the tumorigenesis and prognosis of gastric cancer in a Chinese population.METHODS A total of 898 gastric cancer patients and 992 tumor-free controls were recruited into this study from 2008 to 2013.Gastric cancer patients were followed periodically.Ten single nucleotide polymorphisms(SNPs)in the let-7 gene region or their target mRNAs were genotyped using the MassARRAY system and their associations with the risk for or overall survival of gastric cancer were analyzed.RESULTS All the ten SNPs were in Hardy-Weinberg equilibrium.The C allele of the rs3811463 polymorphism in the 3’-untranslated region(UTR)of LIN28A was associated with a lower risk of gastric cancer[odds ratio(OR)=0.74,95%confidence interval(CI):0.61-0.88,P=0.001]after adjustment for age and Helicobacter pylori status.Seven hundred and thirty-five gastric cancer patients who had undergone radical tumorectomy were included in the survival analysis and their 5-year survival rate was 53.9%(95%CI:50.1%-57.6%).The rs10889677 in the 3’-UTR of IL23R was corresponded to the prognosis of gastric cancer in a dose-response manner,in which the death risk increased by 25%[hazard ratio(HR)=1.25,95%CI:1.04-1.45,P=0.011]with each increase in the number of C alleles after controlling for other potential clinicopathological parameters.CONCLUSION The let-7-related polymorphism rs3811463 in LIN28A is associated with the susceptibility to gastric cancer and the let-7-related polymorphism rs10889677 in IL23R is associated with the prognosis of gastric cancer.

Association of Helicobacter pylori babA2 with peptic ulcer disease and gastric cancer

AIM: To investigate the association between babA2 gene and peptic ulcer disease (PUD) and gastric cancer (GC) in Helicobacter pylori -infected populations. METHODS: We evaluated the relationship between babA2 and clinical outcomes (PUD and GC) using a meta-analysis. A literature search was performed using the PubMed and Web of Science databases for relevant case-control studies that met the defined inclusion criteria. The ORs and 95%CIs were calculated to estimate the association between babA2 genotype and clinical outcomes. A fixed-effect or random-effect model was performed depending on the absence or presence of significant heterogeneity. RESULTS: A total of 25 articles with 38 studies met the inclusion criteria and were finally included in this metaanalysis. The results showed that the babA2 genotype was significantly associated with an increased risk of PUD (OR = 2.069, 95%CI: 1.530-2.794, P < 0.001) and especially in the subgroup of duodenal ulcer (OR = 1.588, 95%CI: 1.141-2.209, P = 0.006). Moreover, a significant association between babA2 gene and PUD and duodenal ulcer (OR = 2.739, 95%CI: 1.860-4.032, P < 0.001; OR = 2.239, 95%CI: 1.468-3.415, P < 0.001, respectively) was observed in western countries but not in Asian countries. CONCLUSION: We demonstrated that the presence of babA2 may be associated with increased risks for PUD, especially duodenal ulcer, in western countries.

Associations between interleukin-1 polymorphisms and gastric cancers among three ethnicities

AIM:To investigate the associations between interleukin(IL)-1B and IL-1RN polymorphisms and gastric cancers among the Tibet,Hui and Han ethnicities.METHODS:Genomic DNA was extracted from peripheral blood of 210,205,and 202 healthy volunteers and from 155,158,and 197 gastric cancer patients from the Tibet,Hui,and Han populations,respectively.Polymorphisms in IL-1B and IL-1RN were analyzed by denaturing high-performance liquid chromatography.RESULTS:Carriers of the IL-1B-31 CC genotype had an increased risk of intestinal type gastric cancer [odds ratio(OR) = 2.17,P = 0.037] in the Tibet ethnicity.Carriers of the IL-1B 2/L genotype had an increased risk of both intestinal and diffuse types of gastric cancer(OR = 2.08,2.31,P = 0.007,0.016,respectively) in the Hui ethnicity.In the Han population,carriers of the IL-1B-31 CC,IL-1B-511CT,TT genotypes had increased risk of intestinal type gastric cancer(OR = 2.51,2.74,5.66,P = 0.005,0.002,0.000,respectively).CONCLUSION:IL-1B and IL-RN genotypes may differentially contribute to gastric cancer among the Tibet,Hui,and Han ethnicities in the Qinghai area of China.

Clinical outcomes and risk factors for perforation in gastric endoscopic submucosal dissection: A prospective pilot study

AIM: To evaluate clinical outcomes and risk factors for endoscopic perforation during endoscopic submucosal dissection (ESD) in a prospective study. METHODS: We investigated the clinical outcomes and risk factors for the development of perforation in 98 consecutive gastric neoplasms undergoing ESD regarding. Demographic and clinical parameters including patient-, tumor-, and treatment-related factors, clinical parameters, and duration of hospital stay were analyzed for risk factors for perforation. In subgroup analysis, we also compared the clinical outcomes between perforation and "silent" free air without endoscopically visible perforation detected only by computed tomography.RESULTS: Perforation was identified in 8.2% of patients. All patients were managed conservatively by the administration of antibiotics. The mean procedure time was significantly longer in patients with endoscopic perforation than in those without. According to the receiver-operating characteristic analysis, the resulting cutoff value of the procedure time for perforation was 115 min (87.5% sensitivity, 56.7% specificity). Prolonged procedure time (≥ 115 min) was associated with an increased risk of perforation (odds ratio 9.15; 95%CI: 1.08-77.54; P = 0.04). Following ESD, body temperature and C-reactive protein level were significantly higher in patients with perforation than in those without (P = 0.02), whereas there was no difference between these patient groups on the starting day of oral intake or of hospitalization. In subgroup analysis, the post-ESD clinical course was not different between endoscopic perforation and silent free air. CONCLUSION: Only prolonged procedure time (≥ 115 min) was significantly associated with perforation. The clinical outcomes of perforation are favorable and are comparable to those of patients with or without silent free air.

Staging laparoscopy improves treatment decision-makingfor advanced gastric cancer

AIM To evaluate the clinical value of staging laparoscopyin treatment decision-making for advancedgastric cancer （GC）.METHODS： Clinical data of 582 patients with advancedGC were retrospectively analyzed. All patientsunderwent staging laparoscopy. The strength ofagreement between computed tomography （CT） stage,endoscopic ultrasound （EUS） stage, laparoscopic stage,and final stage were determined by weighted Kappastatistic （Kw）. The number of patients with treatmentdecision-changes was counted. A χ 2 test was used toanalyze the correlation between peritoneal metastasisor positive cytology and clinical characteristics.RESULTS： Among the 582 patients, the distributions ofpathological T classifications were T2/3 （153, 26.3%）,T4a （262, 45.0%）, and T4b （167, 28.7%）. Treatmentplans for 211 （36.3%） patients were changed after staging laparoscopy was performed. Two （10.5%） of19 patients in M1 regained the opportunity for potentialradical resection by staging laparoscopy. Unnecessarylaparotomy was avoided in 71 （12.2%） patients. Thestrength of agreement between preoperative T stageand final T stage was in almost perfect agreement （Kw= 0.838; 95% confidence interval （CI）： 0.803-0.872;P 〈 0.05） for staging laparoscopy; compared with CTand EUS, which was in fair agreement. The strengthof agreement between preoperative M stage andfinal M stage was in almost perfect agreement （Kw= 0.990; 95% CI： 0.977-1.000; P 〈 0.05） for staginglaparoscopy; compared with CT, which was in slightagreement. Multivariate analysis revealed that tumorsize （≥ 40 mm）, depth of tumor invasion （T4b）, andBorrmann type （Ⅲ or Ⅳ） were significantly correlatedwith either peritoneal metastasis or positive cytology.The best performance in diagnosing P-positive wasobtained when two or three risk factors existed.CONCLUSION： Staging laparoscopy can improvetreatment decision-making for advanced GC anddecrease unnecessary exploratory laparotomy.

Factors associated with metastasis in superior mesenteric vein lymph node in subtotal gastrectomy for gastric cancer:Retrospective case control study

Objective: The revised Japanese treatment guideline for gastric cancer recommends dissection of the superior mesenteric vein lymph node(No. 14v LN) if there is metastasis in infrapyloric lymph node(No. 6 LN). However,it is still controversial whether LN dissection is necessary. The aim of this study was to investigate the factors associated with metastasis in No. 14v LN.Methods: Patients who underwent D2 lymphadenectomy between 2003 and 2010 were included. We excluded patients who underwent total gastrectomy, had multiple lesions, or had missing data about the status of metastasis in the LNs that were included in D2 lymphadenectomy. Clinicopathologic characteristics and the metastasis in regional LNs were compared between patients with No. 14v LN metastasis(14v+) and those without(14v-).Results: Five hundred sixty patients were included in this study. Univariate analysis showed that old age, larger tumor size, tumor location, differentiation, lymphatic invasion, venous invasion, perineural invasion, T classification, and N classification were related to metastasis in No. 14v LN. Multivariate analysis showed differentiation(P=0.027) and N classification(P<0.001) were independent related factors. Metastasis in infrapyloric lymph node(No. 6 LN) and proxiaml splenic lymph node(No. 11p LN) was independently associated with metastasis in No. 14v LN.Conclusions: Differentiation and N classification were independent factors associated with No. 14v LN metastasis, and No. 6 and No. 11p LN metastasis were independent risk factors for No. 14v LN metastasis.

Feasible endoscopic therapy for early gastric cancer

AIM: To analyze the relationship between lymph node metastasis and clinical pathology of early gastric cancer(EGC) in order to provide criteria for a feasible endoscopic therapy.METHODS: Clinical data of the 525 EGC patients who underwent surgical operations between January 2009 and March 2014 in the West China Hospital of Sichuan University were analyzed retrospectively. Clinical pathological features were compared between different EGC patients with or without lymph node metastasis, and investigated by univariate and multivariate analyses for possible relationships with lymph node metastasis.RESULTS: Of the 2913 patients who underwent gastrectomy with lymph node dissection, 529 cases were pathologically proven to be EGC and 525 cases were enrolled in this study, excluding 4 cases of gastric stump carcinoma. Among 233 patients with mucosal carcinoma, 43(18.5%) had lymph node metastasis. Among 292 patients with submucosal carcinoma, 118(40.4%) had lymph nodemetastasis. Univariate analysis showed that gender, tumor size, invasion depth, differentiation type and lymphatic involvement correlated with a high risk of lymph node metastasis. Multivariate analysis revealed that gender(OR = 1.649, 95%CI: 1.091-2.492, P = 0.018), tumor size(OR = 1.803, 95%CI: 1.201-2.706, P = 0.004), invasion depth(OR = 2.566, 95%CI: 1.671-3.941, P = 0.000), histological differentiation(OR = 2.621, 95%CI: 1.624-4.230, P = 0.000) and lymphatic involvement(OR = 3.505, 95%CI: 1.590-7.725, P = 0.002) wereindependent risk factors for lymph node metastasis. Comprehensive analysis showed that lymph node metastasis was absent in patients with tumor that was limited to the mucosa, size ≤ 2 cm, differentiated and without lymphatic involvement.CONCLUSION: We propose an endoscopic therapy for EGC that is limited to the mucosa, size ≤ 2 cm, differentiated and without lymphatic involvement.

Factors affecting occurrence of gastric varioliform lesions: A case-control study

AIM: To investigate the factors influencing the occurrence of gastric varioliform lesions(GVLs) and their possible link with gastric cancer.METHODS: A 1:1 matched case-control study was performed to retrospectively analyze data from 1638 chronic gastritis patients who had undergone gastroscopy at one of two Chinese hospitals between 2009 and 2014. Patients with GVLs(cases) were compared to those without such lesions(controls). Endoscopic and pathological findings were recorded, along with interview information on Helicobacter pylori(H. pylori) infection, medical, drug and family histories, lifestyle and eating habits. The association between each factor and the occurrence of GVLs was estimated, and then multivariate conditional logistic regression was used to evaluate the independent factors.RESULTS: The frequency and severity of glandular atrophy, intestinal metaplasia(IM) and low-grade intraepithelial neoplasia were significantly increased in the GVL group(P < 0.01). Overall analysis showed that H. pylori infection [3.051(2.157, 4.317), P <0.001], allergic respiratory diseases [3.636(2.183, 6.055), P < 0.001], work-related stress [2.019(1.568, 2.600), P < 0.001], irregular meals [2.300(1.462, 3.619), P < 0.001], high intake of spicy food [1.754(1.227, 2.507), P = 0.002] and high intake of fresh fruit [0.231(0.101, 0.529), P = 0.001] were significantly correlated with the occurrence of GVLs(positively, except for the latter). Stratified analyses indicated that pickled food consumption in patients over 50 years old [7.224(2.360, 22.115), P = 0.001] and excessive smoking in men [2.013(1.282, 3.163), P = 0.002] were also positively correlated, and that, for antral GVLs, vegetable consumption [0.491(0.311, 0.776), P = 0.002] was negatively correlated. CONCLUSION: Seven risk factors and two protective factors are determined for GVLs, which were found to be associated with premalignant abnormalities.