Cervical cancer prevention in China: where are we now, and what's next?

Cervical cancer(CC) epidemiology CC, the fourth most frequently diagnosed malignancy in women worldwide, is a major global health challenge, particularly in low-resource regions. Approximately 88.1% of the 604,000 CC new cases occurred in low-and middle-income countries in 2020, and more than 90% of the 342,000 CC deaths occurred in low-and middle-income countries in 2020~1.

Plant-based dietary patterns and risk of esophageal cancer:A prospective cohort study spanning 17 years

Objective: Plant-based diets have multiple health benefits for cancers;however, little is known about the association between plant-based dietary patterns and esophageal cancer(EC).This study presents an investigation of the prospective associations among three predefined indices of plant-based dietary patterns and the risk of EC.Methods: We performed endoscopic screening for 15,709 participants aged 40-69 years from two high-risk areas of China from January 2005 to December 2009 and followed the cohort until December 31, 2022. The overall plant-based diet index(PDI), healthful plant-based diet index(h PDI), and unhealthful plant-based diet index(u PDI), were calculated using survey responses to assess dietary patterns. We applied Cox proportional hazard regression to estimate the multivariable hazard ratios(HRs) and 95% confidence intervals(95% CIs) of EC across 3plant-based diet indices and further stratified the analysis by subgroups.Results: The final study sample included 15,184 participants in the cohort. During a follow-up of 219,365person-years, 176 patients with EC were identified. When the highest quartile was compared with the lowest quartile, the pooled multivariable-adjusted HR of EC was 0.50(95% CI, 0.32-0.77) for h PDI. In addition, the HR per 10-point increase in the h PDI score was 0.42(95% CI, 0.27-0.66) for ECs. Conversely, u PDI was positively associated with the risk of EC, and the HR was 1.80(95% CI, 1.16-2.82). The HR per 10-point increase in the u PDI score was 1.90(95% CI, 1.26-2.88) for ECs. The associations between these scores and the risk of EC were consistent in most subgroups. These results remained robust in sensitivity analyses.Conclusions: A healthy plant-based dietary pattern was associated with a reduced risk of EC. Emphasizing the healthiness and quality of plant-based diets may be important for preventing the development of EC.

Epidemiology of ovarian cancer:a review

Ovarian cancer(OC) is the seventh most commonly diagnosed cancer among women in the world and the tenth most common in China. Epithelial OC is the most predominant pathologic subtype, with five major histotypes that differ in origination,pathogenesis, molecular alterations, risk factors, and prognosis. Genetic susceptibility is manifested by rare inherited mutations with high to moderate penetrance. Genome-wide association studies have additionally identified 29 common susceptibility alleles for OC, including 14 subtype-specific alleles. Several reproductive and hormonal factors may lower risk, including parity, oral contraceptive use, and lactation, while others such as older age at menopause and hormone replacement therapy confer increased risks. These associations differ by histotype, especially for mucinous OC, likely reflecting differences in etiology. Endometrioid and clear cell OC share a similar, unique pattern of associations with increased risks among women with endometriosis and decreased risks associated with tubal ligation. OC risks associated with other gynecological conditions and procedures, such as hysterectomy,pelvic inflammatory disease, and polycystic ovarian syndrome, are less clear. Other possible risk factors include environmental and lifestyle factors such as asbestos and talc powder exposures, and cigarette smoking. The epidemiology provides clues on etiology,primary prevention, early detection, and possibly even therapeutic strategies.

Comparative epidemiology of gastric cancer between Japan and China

AIM:To clarify the similarities and differences in gastric cancer epidemiology between Japan and China.METHODS:A comprehensive literature search of the PubMed database was performed.The relevant literature published in China was also been cited.Data on incidence and mortality rates in 2008 were obtained from the Cancer Mondial database,published by International Agency for Research on Cancer at http://www-dep.iarc.fr/.RESULTS:Gastric cancer remains a significant publichealth burden in both Japan and China.The prevalence of Helicobacter pylori(H.pylori)colonization is high in the adult populations of both countries.Accumulating evidence from intervention studies in both countries has shown the effectiveness of H.pylori eradication in reduc-ing gastric cancer incidence.There are differences,however,in many aspects of gastric cancer,including patterns of incidence and mortality,trends in the prevalence of H.pylori infection,H.pylori strains,the magnitude of risk of gastric cancer related to H.pylori infection,and associations with dietary habits.Compared with China,Japan has seen a more rapid decline in H.pylori infection among adolescents.While Japanese cohort studies have dominated the literature concerning the associations between gastric cancer and dietary habits,numerous case-control studies in China suggest a positive association between a high intake of preserved fish and vegetables and gastric cancer risk.There is a need for a multidisciplinary research approach to understand the interactions between various strains of H.pylori,host factors,and other lifestyle and environmental factors in gastric carcinogenesis in both countries.CONCLUSION:The shared high incidence of gastric cancer and high prevalence of H.pylori,as well as differences in many aspects of gastric cancer,provide an excellent opportunity to establish Sino-Japanese collaborations.

Cervical cancer: Epidemiology, risk factors and screening

Cervical cancer is one of the leading causes of cancer death among females worldwide and its behavior epidemiologically likes a venereal disease of low infectiousness. Early age at first intercourse and multiple sexual partners have been shown to exert strong effects on risk. The wide differences in the incidence among different countries also influenced by the introduction of screening. Although the general picture remains one of decreasing incidence and mortality, there are signs of an increasing cervical cancer risk probably due to changes in sexual behavior. Smoking and human papillomavirus(HPV) 16/18 are currently important issues in a concept of multifactorial, stepwise carcinogenesis at the cervix uteri. Therefore, society-based preventive and control measures, screening activities and HPV vaccination are recommended. Cervical cancer screening methods have evolved from cell morphology observation to molecular testing. High-risk HPV genotyping and liquid-based cytology are common methods which have been widely recommended and used worldwide. In future, accurate,cheap, fast and easy-to-use methods would be more popular. Artificial intelligence also shows to be promising in cervical cancer screening by integrating image recognition with big data technology. Meanwhile, China has achieved numerous breakthroughs in cervical cancer prevention and control which could be a great demonstration for other developing and resource-limited areas. In conclusion, although cervical cancer threatens female health, it could be the first cancer that would be eliminated by human beings with comprehensive preventive and control strategy.

Health economic evaluation on population-based Helicobacter pylori eradication and endoscopic screening for gastric cancer prevention

Gastric cancer is a global public health burden, nearly one million new cases are diagnosed per year worldwide, of which 44% of cases occur in China. The prognosis of gastric cancer varies remarkably by the stage of cancer, and most of the patients in China are diagnosed at advanced stages, resulting in poor prognoses. Effective strategies to reduce the burden of gastric cancer include primary prevention through testing and treatment of Helicobacter pylori(H. pylori) and secondary prevention by screening and early detection. Although many countries have issued management guidelines and consensus reports concerning these strategies, the limited availability of healthcare resources often precludes their widespread implementation. Therefore, assessing the costs, benefits, and harms of population-based intervention measures through health economic evaluation is necessary for informed health policy decisions. Accordingly, we synthesize management approaches from different countries on H. pylori eradication and endoscopic screening, and also summarize recent advancements in health economic evaluations on population-based preventive strategies. The goal of the review is to provide empirical evidence supporting optimal resource allocation, maximizing benefits for the population, and ultimately reducing the burden of gastric cancer.

Non-exercise estimated cardiorespiratory fitness and cancer incidence:The NIH-AARP diet and health study

Background Non-exercise estimated cardiorespiratory fitness(NEE-CRF)has been shown to be associated with mortality,although its association with cancer incidence is unknown.The study aimed to assess the prospective association between NEE-CRF and cancer incidence in a large cohort of men and women.Methods The National Institutes of Health-American Association of Retired Persons diet and health study is a prospective cohort that included 402,548 participants aged 50–71 years who were free from cancer at baseline(1995–1996)(men(n=238,835)and women(n=163,713))and were followed until December 31,2015.The exposure variable was NEE-CRF expressed in metabolic equivalents.NEE-CRF was estimated using a validated equation of self-reported predictors on demographics and lifestyle behaviors derived from baseline questionnaires.Primary outcomes were total cancer incidence and incidence of prostate,breast,lung,and colorectal cancers.Cox proportional hazards models were analyzed for the association between NEE-CRF and cancer incidence outcomes adjusted for established cancer risk factors.Results During 13.7±3.2 years of follow-up(mean±SD),64,344 men and 31,315 women developed a new cancer.For every 1-metabolic equivalent higher NEE-CRF,the hazard ratios and 95%confidence intervals(95%CIs)were 0.96(95%CI:0.94–0.97)and 0.88(95%CI:0.84–0.92)of total and colorectal cancer incidence among men,and 0.95(95%CI:0.93–0.97)and 0.94(95%CI:0.91–0.97)of total and breast cancer incidence among women,respectively(all p<0.001).NEE-CRF was not associated with incidence of prostate and lung cancers in men or colorectal and lung cancers in women.Conclusion These results suggest that higher CRF levels,as assessed by the applied non-exercise estimated method,may provide preventive benefits against the development of cancer,while low CRF could potentially serve as a modifiable cancer risk factor.Integrating NEE-CRF into screening paradigms and referring low-fit individuals to improve CRF could complement the public health prevention strategy against cancer.

Cohort profile: design and methods of the Chinese colorectal, breast, lung, liver, and stomach cancer screening trial(C-BLAST)

Given the rapid changes in social structure(urbanization),economic structure(industrialization),and demographic structure(population aging)in China,cancer has become a major public health problem1.Extensive evidence has indicated that screening can decrease cancer mortality,particularly among high-risk groups,and several representative national and regional cancer screening programs have been launched in China to cope with the increasing burden of cancer.

Clinical outcomes for men with positive surgical margins after radical prostatectomy—results from the South Australian Prostate Cancer Clinical Outcomes Collaborative community-based registry

Objective Positive surgical margins(PSMs)after radical prostatectomy(RP)indicate failure of surgery to completely clear cancer.PSMs confer an increased risk of biochemical recurrence(BCR),but how more robust outcomes are affected is unclear.This study investigated factors associated with PSMs following RP and determined their impact on clinical outcomes(BCR,second treatment[radiotherapy and/or androgen deprivation therapy],and prostate cancer-specific mortality[PCSM]).Methods The study cohort included men diagnosed with prostate cancer(pT2-3b/N0/M0)between January 1998 and June 2016 who underwent RP from the South Australian Prostate Cancer Clinical Outcomes Collaborative database.Factors associated with risk of PSMs were identified using Poisson regression.The impact of PSMs on clinical outcomes(BCR,second treatment,and PCSM)was assessed using competing risk regression.Results Of the 2827 eligible participants,28%had PSMs—10%apical,6%bladder neck,17%posterolateral,and 5%at multiple locations.Median follow-up was 9.6 years with 81 deaths from prostate cancer recorded.Likelihood of PSM increased with higher pathological grade and pathological tumor stage,and greater tumour volume,but decreased with increasing surgeon volume(odds ratio[OR]:0.93;95%confidence interval[CI]:0.88-0.98,per 100 previous prostatectomies).PSMs were associated with increased risk of BCR(adjusted sub-distribution hazard ratio[sHR]2.5;95%CI 2.1-3.1)and second treatment(sHR 2.9;95%CI 2.4-3.5).Risk of BCR was increased similarly for each PSM location,but was higher for multiple margin sites.We found no association between PSMs and PCSM.Conclusion Our findings support previous research suggesting that PSMs are not independently associated with PCSM despite strong association with BCR.Reducing PSM rates remains an important objective,given the higher likelihood of secondary treatment with associated comorbidities.

Estimation of economic burden throughout course of cervical squamous intraepithelial lesion and cervical cancer in China:A nationwide multicenter cross-sectional study

Objective: Cervical squamous intraepithelial lesion(SIL) and cervical cancer are major threats to females' health and life in China, and we aimed to estimate the economic burden associated with their diagnosis and treatment.Methods: A nationwide multicenter, cross-sectional, hospital-based survey was conducted in 26 qualified hospitals across seven administrative regions of China. We investigated females who had been pathologically diagnosed with SIL and cervical cancer, and included five disease courses(“diagnosis”, “initial treatment”,“chemoradiotherapy”, “follow-up” and “recurrence/progression/metastasis”) to estimate the total costs. The median and interquartile range(IQR) of total costs(including direct medical, direct non-medical, and indirect costs), reimbursement rate by medical insurance, and catastrophic health expenditures in every clinical stage were calculated.Results: A total of 3,471 patients in different clinical stages were analyzed, including low-grade SIL(LSIL)(n=549), high-grade SIL(HSIL)(n=803), cervical cancer stage ⅠA(n=226), ⅠB(n=610), ⅡA(n=487), ⅡB(n=282), Ⅲ(n=452) and Ⅳ(n=62). In urban areas, the estimated total costs of LSIL and HSIL were $1,637.7(IQR:$956.4-$2,669.2) and $2,467.1(IQR:$1,579.1-$3,762.3), while in rural areas the costs were $459.0(IQR:$167.7-$1,330.3) and $1,230.5(IQR:$560.6-$2,104.5), respectively. For patients with cervical cancer stage ⅠA,ⅠB, ⅡA, ⅡB, and Ⅲ-Ⅳ, the total costs were $15,034.9(IQR:$11,083.4-$21,632.4), $19,438.6(IQR:$14,060.0-$26,505.9), $22,968.8(IQR:$16,068.8-$34,615.9), $26,936.0(IQR:$18,176.6-$41,386.0) and $27,332.6(IQR:$17,538.7-$44,897.0), respectively. Medical insurance covered 43%-55% of direct medical costs for cervical cancer patients, while the coverage for SIL patients was 19%-43%. For most cervical cancer patients, the expense was catastrophic, and the extent of catastrophic health expenditure was about twice large for rural patients than that for urban patients in each stage.Conclusions: The economic burden of SIL and cervical cancer in China is substantial, with a significant proportion of the costs being avoidable for patients with LSIL. Even for those with medical insurance, catastrophic health expenditures are also a major concern for patients with cervical cancer, particularly for those living in rural areas.

Comparative effects of different types of exercise on health-related quality of life during and after active cancer treatment:A systematic review and network meta-analysis

Background The positive influence of most types of exercise has been reported repeatedly,but what the most effective exercise approaches are for improving health-related quality of life(HRQoL)in people with cancer remains unknown.The aim of this systematic review and network meta-analysis was to synthesize the evidence from intervention studies to assess the effects of different types of exercise on HRQoL during and after cancer treatment.Methods MEDLINE,SPORTDiscus,the Cochrane Library,Web of Science,and Scopus were searched for randomized controlled trials aimed at testing the effects of exercise interventions meant to improve HRQoL in people with cancer.Separate analyses were conducted for HRQoL as measured by general and cancer-specific questionnaires.We also evaluated whether the effects of exercise were different during and after cancer treatment in both the physical and mental HRQoL domains.Results In total,93 studies involving 7435 people with cancer were included.Network effect size estimates comparing exercise intervention vs.usual care were significant for combined exercise(0.35,95%confidence interval(95%CI):0.14–0.56)for HRQoL as measured by general questionnaires,and for combined(0.31,95%CI:0.13–0.48),mind–body exercise(0.54,95%CI:0.18–0.89),and walking(0.39,95%CI:0.04–0.74)for HRQoL as measured by cancer-specific questionnaires.Conclusion Exercise programs combining aerobic and resistance training can be recommended to improve HRQoL during and after cancer treatment.The scarcity and heterogeneity of these studies prevents us from making recommendations about other exercise modalities due to insufficient evidence.

Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults

Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity.

Deep insight into the B-cell associated tertiary lymphoid structure and tumor immunotherapy

Bod et al.1 recently published a study in Nature that garnered attention to B cell-associated anti-tumor immunity and immunotherapy of melanoma and other tumors1.As a promising supplemental immunotherapy to mainstream methods that target T and natural killer(NK)cells,B cell-associated anti-tumor immunotherapy is promising。

Epidemiology,etiology,and prevention of esophageal squamous cell carcinoma in China

Esophageal cancer is one of the most fatal diseases worldwide mainly because of its rapid progression and poor prognosis.Although the incidence of esophageal adenocarcinoma has markedly risen in North America and Europe in the past several decades, esophageal squamous cell carcinoma is still the predominant subtype of esophageal cancer, especially in China. It accounts for more than 90% of all esophageal squamous cell carcinoma cases in China. Geographical differentiation is one of the most distinctive characteristics of esophageal cancer. The progression, risk factors, and prognosis of these two subtypes of esophageal cancer differ. This study reviews the epidemiology, etiology, and prevention of esophageal squamous cell carcinoma in China, thereby providing systematic references for policy-makers who will decide on issues of esophageal cancer prevention and control.

Incidence and mortality of colorectal cancer in China, 2011

Objective： Colorectal cancer is the third most common type of cancer and the fourth leading cause of cancer-related death in the world. This article provides the most up-to-date overview of colorectal cancer burden in China. Methods： Totally 234 cancer registries submitted data of 2011 to the National Central Cancer Registry （NCCR）. Qualified data from 177 registries was pooled and analyzed. The crude incidence and mortality rates of colorectal cancer were calculated by age, gender and geographic area. The numbers of new cases and deaths were estimated using the 5-year age-specific cancer incidence/mortality rates and the corresponding populations. China census in 2000 and Segi＇s world population were applied for age standardized rates. Results： The estimate of new cases diagnosed with colorectal cancer of China in 2011 was 310,244 （178,404 for males and 131,840 for females, 195,117 in urban areas and 115,128 in rural areas）, accounting for 9.20% of overall new cancer cases. The crude incidence of colorectal cancer ranked fourth in all cancer sites with rate of 23.03/100,000 （25.83/100,000 for males and 20.08/100,000 for female, 28.25/100,000 in urban areas and 17.54/100,000 in rural areas）. The age-standardized rates by China population and by World population were 16.79/100,000 and 16.52/100,000, respectively. The estimated number of colorectal cancer deaths of China in 2011 was 149,722 （86,427 for males and 63,295 for females, 91,682 in urban areas and 58,040 in rural areas）, accounting for 7.09% of overall cancer deaths. The crude mortality rate for colorectal cancer ranked fifth leading cause of cancer-related death in all cancer sites with rate of 11.11/100,000 （12.51/100,000 for males and 9.64/100,000 for female, 13.27/100,000 in urban areas and 8.84/100,000 in rural areas）. The age-standardized rates by China population and by World population for mortality were 7.77/100,000 and 7.66/100,000, respectively. For both of incidence and mortality, the rates of colorectal cancer were much higher in males than in females, and in rural areas than in urban areas. The rate of colorectal cancer increased greatly with age, especially after 40 or 45 years old. Conclusions： Colorectal cancer is a relative common cancer in China, especially for males in urban areas. Targeted prevention and early detection programs should be carried out.

Oral cancer incidence and mortality in China, 2011

Objective： To descript the incidence and mortality rates of oral cancer among Chinese population in 2011, and provide valuable data for oral cancer prevention and research. Methods： Data from 177 population-based cancer registries distributed in 28 provinces were accepted for this study after evaluation based on quality control criteria, covering a total of 175,310,169 populations and accounting for 13.01% of the overall national population in 2011. Incidence and mortality rates were calculated by area, gender and age groups. The numbers of new cases and deaths were estimated using the 5-year age-specific cancer incidence/mortality rates and the corresponding populations. The Chinese population in 2000 and World Segi＇s population were used for age-standardized rates. Results： The estimate of new cases diagnosed with oral cancer was 39,450 including 26,160 males and 13,290 females. The overall crude incidence rate for oral cancer was 2.93/100,000. The age-standardized rates by China （ASRcN） population and by World population （ASRwld） were 2.22/100,000 and 2.17/100,000, respectively. Among subjects aged 0-74 years, the cumulative incidence rate was 0.25%. The estimated number of oral cancer deaths of China in 2011 was 16,933, including 11,794 males and 5,139 females. The overall crude mortality rate was 1.26/I00,000, accounting for 0.80% of all cancer deaths. The ASRcN and ASP^Id for mortality were 0.90/100,000 and 0.89/100,000, respectively. Among subjects aged 0-74 years, the cumulative mortality rate was 0.10%. The incidence and mortality rates of oral cancer were much higher in males and urban areas than in females and rural areas. In addition, the incidence and mortality rates were increased by the raising of ages. Conclusions： Results in the study may have important roles for oral cancer prevention and research. Although oral cancer burden of China is not high, we must pay attention to this malignancy as well. In addition, further researches need to be done for primary and secondary prevention research of oral cancer, especially for the high risk population.

Screening for gastric cancer in China:Advances,challenges and visions

Gastric cancer(GC)is one of the major cancers in China and all over the world.Most GCs are diagnosed at an advanced stage with unfavorable prognosis.Along with some other countries,China has developed the government-funded national screening programs for GC and other major cancers.GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs(Japan and Korea)and in studies based on selected Chinese populations.The screening of GC relies mostly on gastroendoscopy,the accuracy,reliability and safety of which have been indicated by previous studies.However,considering its invasive screening approach,requirements on skilled endoscopists and pathologists,and a high cost,developing noninvasive methods to amend endoscopic screening would be highly needed.Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen,gastrin,and Helicobacter pylori antibodies has been proposed for risk stratification,seeking to narrow down the high-risk populations for further endoscopy.Despite all the achievements of endoscopic screening,evidence on appropriate screening age,intervals for repeated screening,novel biomarkers promoting precision prevention,and health economics need to be accumulated to inform policymakers on endoscopic screening in China.With the guide of Health China 2030 Planning Outline,we have golden opportunities to promote prevention and control of GC.In this review,we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening,aiming for featuring the latest advances and key challenges,and illustrating future visions of GC screening.

Household air pollution and lung cancer in China:a review of studies in Xuanwei

Over half of the world's population is exposed to household air pollution from the burning of solid fuels at home. Household air pollution from solid fuel use is a leading risk factor for global disease and remains a major public health problem, especially in low- and mid-income countries. This is a particularly serious problem in China, where many people in rural areas still use coal for household heating and cooking. This review focuses on several decades of research carried out in Xuanwei County, Yunnan Province, where household coal use is a major source of household air pollution and where studies have linked household air pollution exposure to high rates of lung cancer. We conducted a series of case-control and cohort studies in Xuanwei to characterize the lung cancer risk in this population and the factors associated with it. We found lung cancer risk to vary substantially between different coal types, with a higher risk associated with smoky(i.e., bituminous) coal use compared to smokeless(i.e., anthracite) coal use. The installation of a chimney in homes resulted in a substantial reduction in lung cancer incidence and mortality. Overall, our research underscores the need among existing coal users to improve ventilation, use the least toxic fuel, and eventually move toward the use of cleaner fuels, such as gas and electricity.

Gene-diet interactions in gastric cancer risk: A systematic review

AIM:To conduct a systematic review of the published epidemiological studies investigating the association of the interactions between gene variants and dietary intake with gastric cancer risk.METHODS:A literature search was conducted in PubMed,EMBASE,and MEDLINE for articles published between January 2000 and July 2013,and 38 studies were identified.Previous studies included various dietary factors(e.g.,fruits and vegetables,soybean products,salt,meat,and alcohol)and genetic variants that are involved in various metabolic pathways.RESULTS:Studies suggest that individuals who carry high-risk genetic variants and demonstrate particular dietary habits may have an increased risk of gastric cancer compared with those who do not carry high-risk genetic variants.Distinctive dietary patterns and variations in the frequency of genetic variants may explain the higher incidence of gastric cancer in a particular region.However,most previous studies have limitations,such as a small sample size and a retrospective casecontrol design.In addition,past studies have been unable to elucidate the specific mechanism in gene-diet interaction associated with gastric carcinogenesis.CONCLUSION:Additional large prospective epidemiological and experimental studies are required to identify the gene-diet metabolic pathways related to gastric cancer susceptibility.

A systematic review of metabolomic profiling of gastric cancer and esophageal cancer

Objective:Upper gastrointestinal(UGI)cancers,predominantly gastric cancer(GC)and esophageal cancer(EC),are malignant tumor types with high morbidity and mortality rates.Accumulating studies have focused on metabolomic profiling of UGI cancers in recent years.In this systematic review,we have provided a collective summary of previous findings on metabolites and metabolomic profiling associated with GC and EC.Methods:A systematic search of three databases(Embase,PubMed,and Web of Science)for molecular epidemiologic studies on the metabolomic profiles of GC and EC was conducted.The Newcastle–Ottawa Scale(NOS)was used to assess the quality of the included articles.Results:A total of 52 original studies were included for review.A number of metabolites were differentially distributed between GC and EC cases and non-cases,including those involved in glycolysis,anaerobic respiration,tricarboxylic acid cycle,and protein and lipid metabolism.Lactic acid,glucose,citrate,and fumaric acid were among the most frequently reported metabolites of cellular respiration while glutamine,glutamate,and valine were among the most commonly reported amino acids.The lipid metabolites identified previously included saturated and unsaturated free fatty acids,aldehydes,and ketones.However,the key findings across studies to date have been inconsistent,potentially due to limited sample sizes and the majority being hospital-based case-control analyses lacking an independent replication group.Conclusions:Studies on metabolomics have thus far provided insights into etiological factors and biomarkers for UGI cancers,supporting the potential of applying metabolomic profiling in cancer prevention and management efforts.