Causal relationships between coffee intake, apolipoprotein B and gastric, colorectal, and esophageal cancers: univariable and multivariable Mendelian randomization.

PURPOSE: Coffee intake and apolipoprotein B levels have been linked to gastric, colorectal, and esophageal cancers in numerous recent studies. However, whether these associations are all causal remains unestablished. This study aimed to assess the potential causal associations of apolipoprotein B and coffee intake with the risk of gastric, colorectal, and esophageal cancers using Mendelian randomization analysis. METHODS: In this study, we utilized a two-sample Mendelian randomization analysis to access the causal effects of coffee intake and apolipoprotein B on gastric, colorectal, and esophageal cancers. The summary statistics of coffee intake (n = 428,860) and apolipoprotein B (n = 439,214) were obtained from the UK Biobank. In addition, the summary statistics of gastric cancer, colorectal cancer, and esophageal cancer were obtained from the FinnGen biobank (n = 218,792). Inverse variance weighted, MR-Egger, weighted median, and weighted mode were applied to examine the causal relationship between coffee intake, apolipoprotein B and gastric, colorectal, and esophageal cancers. MR-Egger intercept test, Cochran's Q test, and leave-one-out analysis were performed to evaluate possible heterogeneity and pleiotropy. Steiger filtering and bidirectional mendelian randomization analysis were performed to evaluate the possible reverse causality. RESULTS: The result of the inverse variance weighted method indicated that apolipoprotein B levels were significantly associated with a higher risk of gastric cancer (OR = 1.392, 95% CI 1.027-1.889, P = 0.0333) and colorectal cancer (OR = 1.188, 95% CI 1.001-1.411, P = 0.0491). Furthermore, multivariable Mendelian randomization analysis also revealed a positive association between apolipoprotein B levels and colorectal cancer risk, but the effect of apolipoprotein B on gastric cancer risk disappeared after adjustment of coffee intake, body mass index or lipid-related traits. However, we did not discover any conclusive evidence linking coffee intake to gastric, colorectal, or esophageal cancers. CONCLUSIONS: This study suggested a causal association between genetically increased apolipoprotein B levels and higher risk of colorectal cancer. No causal relationship was observed between coffee intake and gastric, colorectal, or esophageal cancers.

Association between type of drinking water and upper gastrointestinal cancer incidence in the Linxian General Population.

BACKGROUND: This study aimed to explore the association between drinking water source and risk of upper gastrointestinal (UGI) cancer, including esophageal cancer (EC) and gastric cancer (GC), in the Linxian General Population Nutrition Intervention Trial (NIT) cohort. METHODS: In this study, we used data from the Linxian NIT cohort, which included 29,584 healthy adults aged 40 to 69 years. Subjects were enrolled in April 1986 and followed up until March 2016. Tap water drinking status and demographic characteristics were collected at baseline. Subjects who drank tap water were treated as the exposed group. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazard model. RESULTS: A total of 5,463 cases of UGI cancer were identified during the 30-year follow-up period. After adjusting for multiple factors, the incidence rate of UGI cancer in participants who drank tap water was significantly lower compared with individuals in the control (HR = 0.91, 95% CI: 0.86-0.97). A similar association was observed between tap water drinking and EC incidence (HR = 0.89, 95% CI: 0.82-0.97). The association between drinking tap water and risk of UGI cancer and EC incidence did not vary across the subgroup by age and gender (All Pinteraction > 0.05). For EC incidence, an interaction effect was observed for riboflavin/niacin supplements and drinking water source (Pinteraction = 0.03). No association was observed between drinking water source and GC incidence. CONCLUSIONS: In this prospective cohort study in Linxian, participants who drank tap water had a lower risk of EC incidence. As a source of drinking water, use of tap water may reduce the risk of EC by avoiding exposure to nitrate/nitrite. Measures should be taken to improve the quality of drinking water in high-incidence areas of EC. TRIAL REGISTRATION: The trial is registered with ClinicalTrials.gov (NCT00342654, 21/06/2006), and the trial name is Nutrition Intervention Trials in Linxian Follow-up Study.

Esophagus cancer and essential trace elements.

Numerous epidemiological and laboratory studies on essential trace elements have reported protective associations in developing various cancer types, including esophagus cancer (EC). However, the results are not always consistent. Some essential trace elements could play a vital role in preventing esophagus cancer. Some showed no association with esophageal cancer risk, while others harmed individuals. This article reviews the association between the intake or supplementation of essential trace elements (especially zinc, copper, iron, and selenium) and the risk of esophageal cancer. Generally, zinc intake may decrease the risk of esophageal cancer (EC), especially in high esophageal squamous cell carcinoma (ESCC) prevalence regions. The association between copper supplementation and EC remains uncertain. Total iron consumption is thought to be associated with lower EC risk, while heme iron intake may be associated with higher EC risk. Selenium intake showed a protective effect against EC, especially for those individuals with a low baseline selenium level. This review also prospects the research direction of the association between EC and essential trace elements.

Coffee consumption and cancer risk: a Mendelian randomisation study.

BACKGROUND: Coffee contains many bioactive chemicals and associations with cancer have been reported in observational studies. In this Mendelian randomisation (MR) study we investigated the causal associations of coffee consumption with a broad range of cancers. MATERIALS AND METHODS: Twelve independent genetic variants proxied coffee consumption. Genetically-predicted risk of any cancer (59,647 cases) and 22 site-specific cancers was estimated in European-descent individuals in UK Biobank. Univariable and multivariable MR analyses were conducted. RESULTS: Genetically-predicted coffee consumption was not associated with risk of any cancer in the main analysis (OR 1.05, 95% CI 0.98-1.14, p = 0.183) but was associated with an increased risk of digestive system cancer (OR 1.28, 95% CI 1.09-1.51, p = 0.003), driven by a strong association with oesophageal cancer (OR 2.79, 95% CI 1.73-4.50, p = 2.5×10-5). This association was consistent after adjustment for genetically-predicted body mass index, smoking and alcohol consumption. There was no strong evidence supporting a causal relationship between genetically-predicted coffee consumption and the majority of cancers studied. However, genetically-predicted coffee consumption was associated with increased risk of multiple myeloma (OR 2.25, 95% CI 1.30-3.89, p = 0.004) and reduced ovarian cancer risk (OR 0.63, 95% CI 0.43-0.93, p = 0.020). CONCLUSIONS: This MR study provides strong support for a causal association of coffee consumption with oesophageal cancer, but not for the majority of cancer types, and the underlying mechanisms require investigation.

Diet and Esophageal Cancer Risk: An Umbrella Review of Systematic Reviews and Meta-Analyses of Observational Studies.

Diet may play an important role in the occurrence of esophageal cancer (EC). The aim of this umbrella review was to grade the evidence for the association between dietary factors and EC risk. A protocol for this review was registered with the PROSPERO database (CRD42021283232). Publications were identified by searching PubMed, EMBASE, Web of Science, Cochrane Database of Systematic Reviews, and CINAHL databases. Only systematic reviews and meta-analyses of observational studies (cohort studies, case-cohort studies, nested case-control studies) were eligible. AMSTAR-2 (A Measurement Tool to Assess Systematic Reviews) was used to assess the methodological quality of included systematic reviews. For each association, random-effects pooled effect size, 95% CI, number of cases, 95% prediction interval, heterogeneity, small-study effect, and excess significance bias were calculated to grade the evidence. From 882 publications, 107 full-text articles were evaluated for eligibility, and 20 systematic reviews and meta-analyses describing 32 associations between dietary factors and EC risk were included in the present umbrella review. By assessing the strength and validity of the evidence, 1 association (positively associated with alcohol intake) was supported by highly suggestive evidence and 1 (inversely associated with calcium intake) showed a suggestive level of evidence. Evidence for 7 associations was weak (positively associated with red meat and processed-meat intake; inversely associated with whole grains, fruits, green leafy vegetables, green tea, and zinc intake). The remaining 23 associations were nonsignificant. In conclusion, the findings of this umbrella review emphasize that habitually consuming calcium, whole grains, fruits, green leafy vegetables, green tea, and zinc and reducing alcohol, red meat, and processed-meat intake are associated with a lower risk of EC. Since this umbrella review included only observational study data and some of the associations were graded as weak, caution should be exercised in interpreting these relations.

Statins and the risk of gastric, colorectal, and esophageal cancer incidence and mortality: a cohort study based on data from the Korean national health insurance claims database.

BACKGROUND: This study investigated the association between the use of statins, the incidence of gastric, colorectal, and esophageal cancers, and mortality between January 2005 and June 2013 in South Korea. METHODS: We compared patients aged 45-70 years statin users for at least 6 months to non-statin users matched by age and sex, from 2004 to June 2013 using the National Health Insurance database. Main outcomes were gastric, colorectal, and esophageal cancer incidence and mortality. Cox proportional hazard regression was used to calculate the adjusted hazard ratios (aHRs) and 95% confidence intervals (95% CIs) among overall cohort and matched cohort after propensity score matching with a 1:1 ratio. RESULTS: Out of 1,008,101 people, 20,473 incident cancers, 3938 cancer deaths occurred and 7669 incident cancer, 1438 cancer death in matched cohort. The aHRs for the association between the risk of cancers and statin use were 0.7 (95% CI 0.65-0.74) for gastric cancer, 0.73 (95% CI 0.69-0.78) for colorectal cancer, and 0.55 (95% CI 0.43-0.71) for esophageal cancer. There were associations between statin use and decreased gastric cancer mortality (HR 0.46, 95% CI 0.52-0.57), colorectal cancer mortality (HR 0.43, 95% CI 0.36-0.51), and esophageal cancer mortality (HR 0.41, 95% CI 0.27-0.50) in the overall cohort and this pattern was similar in the matched cohort. DISCUSSION: Statin use for at least 6 months was significantly associated with a lower risk of stomach, colorectal, and esophageal cancer incidence as well as cancer mortality after a diagnosis.

Mortality after multivitamin supplementation: Nearly 35-year follow-up of the randomized Linxian Dysplasia Nutrition Intervention Trial.

BACKGROUND: The objective of this study was to update the association between multivitamin supplementation and total or cause-specific mortality in a population with a high prevalence of undernutrition in China. METHODS: The Linxian Dysplasia Nutrition Intervention Trial was a randomized, double-blind, placebo-controlled trial in which 3318 persons aged 40-69 years with esophageal squamous dysplasia were assigned to receive daily multivitamin supplementation or a placebo for 6 years and were followed for 29 years. The primary outcome was esophageal/gastric cardia cancer mortality. The data were analyzed with Cox proportional hazards regression models. Subgroup analyses were performed by common characteristics such as age and gender. RESULTS: The cumulative total mortality was 83.5%. Multivitamin supplementation did not affect total or cause-specific mortality in the participants as a whole (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.89-1.03). Subgroup analyses showed that no association between multivitamin supplementation and all-cause mortality was observed in men (HR, 0.90; 95% CI, 0.81-1.01), women (HR, 1.01; 95% CI, 0.91-1.12), younger participants (HR, 0.97; 95% CI, 0.87-1.08), or older participants (HR, 0.94; 95% CI, 0.85-1.04). Significant reductions in heart disease mortality (HR, 0.64; 95% CI, 0.47-0.87) and cerebrovascular disease mortality (HR, 0.74; 95% CI, 0.56-1.00) were seen in older men. In a subgroup of younger men and a subgroup of moderate or severe dysplasia, subjects receiving multivitamin supplementation had a lower risk of esophageal/cardia cancer mortality (HR for younger men, 0.76; 95% CI, 0.58-0.99; HR for moderate or severe dysplasia, 0.76; 95% CI, 0.58-1.00). No association between multivitamin supplementation and any cause-specific mortality was observed in a mild dysplasia population. CONCLUSIONS: Multivitamin supplementation in a population with esophageal squamous dysplasia was not associated with the risk of total mortality in the 35-year follow-up of this randomized controlled trial. In light of this and previous trials, multivitamin supplements should be used thoughtfully to improve health status of populations with esophageal squamous dysplasia. LAY SUMMARY: Multivitamin supplementation is common, yet its effect on mortality is unclear. The aim of this study was to update the long-term effects of multivitamin supplementation on total and cause-specific mortality during nearly 35 years of follow-up in the Linxian Dysplasia Nutrition Intervention Trial in China. Multivitamin supplementation in a population with esophageal squamous dysplasia was not associated with the risk of total mortality in the 35-year follow-up of this randomized controlled trial, and this indicates that multivitamin supplements should be used thoughtfully to improve health status.

Dietary fatty acid patterns and risk of oesophageal squamous cell carcinoma.

Background: To characterize and examine the associations between dietary fatty acid intake patterns and the risk of oesophageal squamous cell carcinoma (ESCC). Methods: A total of 422 patients and 423 controls were recruited. Dietary fatty acids were entered into a factor analysis. Multivariable logistic regression and restricted cubic spline were used to evaluate the risk of ESCC specific for different dietary fatty acid patterns (FAPs). A forest plot was applied to show the association between FAPs and ESCC risk after stratification by lifestyle exposure factors (tobacco smoking, alcohol drinking, pickled food, fried food, hot food, hard food). Results: The factor analysis generated four major fatty acid patterns: a medium- and long-chain SFA (MLC-SFA) pattern; an even-chain unsaturated fatty acid (EC-UFA) pattern, a saturated fatty acid (SFA) pattern and an n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) pattern. In the multivariate-adjusted model, the odds ratios (ORs) with 95% confidence intervals (CIs) of ESCC were 2.07 (1.31, 3.26) and 0.53 (0.34, 0.81) for the highest versus the lowest tertiles of the EC-UFA pattern and n-3 LC-PUFA pattern, respectively. The MLC-SFA and SFA patterns were not associated with ESCC. An association between FAPs and ESCC risk after stratification by lifestyle exposure factors was also observed. Conclusions: Our study indicates that the EC-UFA pattern and n-3 LC-PUFA pattern intake are associated with ESCC, providing a potential dietary intervention for ESCC prevention.

Dietary intake of monounsaturated and polyunsaturated fatty acids is related to the reduced risk of esophageal squamous cell carcinoma.

BACKGROUND: The relationship of consumption of dietary fat and fatty acids with esophageal squamous cell carcinoma (ESCC) risk remains unclear. This study aimed to explore the relationship of dietary fat and fatty acids intake with ESCC risk. METHODS: This case-control study included 879 incident cases and 892 community-based controls recruited from Southwest China. A food frequency questionnaire was adopted to collect information about dietary information, and intake of fat, saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA), and total fatty acid (TFA) was calculated. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were estimated using the logistic regression model. RESULTS: When comparing the highest with lowest intake quintiles, MUFA (OR: 0.33, 95% CI: 0.21-0.51), PUFA (OR: 0.32, 95% CI: 0.20-0.51), and TFA (OR: 0.44, 95% CI: 0.28-0.70) were related to a reduced risk of ESCC after adjusting for confounders; for non-drinkers rather than drinkers, the intake of SFA was significantly related to a 61% (OR: 0.39, 95% CI: 0.19-0.81) reduced risk of ESCC when comparing the highest with the lowest intake quintiles. Dietary fat was not related to the risk of ESCC. CONCLUSIONS: This study suggested that the more intake of MUFA and PUFA, the lower risk of ESCC, whereas the protective effect of TFA was only observed among non-drinkers. Strategic nutritional programs should consider food rich in unsaturated fatty acids to mitigate the occurrence of ESCC.

Hot Tea Drinking and the Risk of Esophageal Cancer: A Systematic Review and Meta-Analysis.

This study aimed to explore the association between hot tea drinking and the risk of esophageal cancer. PubMed, Web of Science, Embase, Scopus and Cochrane library were searched for relevant studies from inception to October 29, 2020 by using (Tea OR "Green Tea" OR "Black Tea") AND ("Esophageal Neoplasms" OR "Esophageal Cancer" OR "Esophagus Cancer") as key words. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the literatures. The meta-analysis was performed using the Revman 5.3 and Stata 13.0 software. The subgroup analyses were conducted on publication year, population regions, tea type, tea temperature, and type of esophageal cancer, and the publication bias was calculated using the funnel plot and Begg's regression. A total of 12 case-control studies with 5253 cases and 8273 controls were included. The meta-analysis displayed that hot tea drinking was significantly associated with the risk of esophageal cancer (pooled odds ratio, 2.04; 95% CI, 1.78-2.31). However, the research evidence is still limited, therefore, it needs further discussion.

Risk Factors Related to Esophageal Cancer, a Case-Control Study in Herat Province of Afghanistan.

BACKGROUND: The Herat province of Afghanistan is located on the Asian Esophageal Cancer Belt (AECB), a wide area in Central and Eastern Asia where very high rates of esophageal cancer (EC) have been observed. Several risk factors have been reported in the AECB Region by previous studies. Considering lack of information in Afghanistan on this issue, a study was conducted to determine the major risk factors related to EC in order to guide protective measures. METHODS: A population-based case-control study was performed from July 2015 to August 2016 among 657 EC patients in the Herat Province and 180 histopathological confirmed cases and 189 controls were interviewed. A structured questionnaire was used and face-to-face interviews were conducted. RESULTS: Low body mass index (BMI), low socio-economic status, family history of EC, consumption of dark tea, very hot beverage and qulurtoroosh were found to be statistically significant for EC and esophageal squamous cell carcinoma (ESCC) in univariate analyses. According to multivariate analyses, sex (OR=2.268; 95% CI=1.238-4.153), very hot beverages (OR=2.253; 95% CI=1.271- 3.996), qulurtoroosh (OR=5.679; 95% CI=1.787-18.815), dark tea (OR=2.757; 95% CI=1.531-4.967), high previous BMI (OR=0.215; 95% CI=0.117-0.431) and low socio-economic status (OR=1.783; 95% CI=1.007-3.177) were associated with ESCC. Being male was found to increase the risk of ESCC with OR=2.268 (95% CI=1.238-4.153). CONCLUSION: Consuming very hot beverages dark tea and a local food, qulurtoroosh, were found as important risk factors for EC. Our findings warrant further studies and necessitate the implementation of protective measures for EC which is one of the leading cancers in the region.

Meta-Analysis of the Association between Asbestos Exposure and Esophageal Cancer.

BACKGROUND: We conducted a meta-analysis to quantitatively assess the association between asbestos exposure and esophageal cancer. METHODS: We systematically collected articles from three electronic databases and calculated the pooled standardized mortality rate (SMR) from the meta-analysis. Subgroup analysis according to the type of asbestos exposure, follow-up years, sample size, industry classification, sex, and high-dose exposure was conducted. RESULTS: From 242 studies, 34 cohort studies were included in our meta-analysis. Pooled SMR was positively associated with asbestos exposure and esophageal cancer (pooled SMR = 1.28; 95% confidence interval (CI) 1.19-1.38, p < 0.00001). In the subgroup analysis, (1) chrysolite, (2) four groups with follow-up over ten years, (3) the textile industry and shipyard, (4) both male and female, and (5) eight studies on highest asbestos exposure, all the subgroups showed significantly increased pooled SMRs. CONCLUSION: Asbestos exposure was significantly and positively associated with esophageal cancer, especially chrysolite. Considering the long latency period, we suggest that patients should be followed up for cancer, including esophageal cancer, for over ten years.

Independent and opposing associations of dietary phytosterols intake and PLCE1 rs2274223 polymorphisms on esophageal squamous cell carcinoma risk.

PURPOSE: This study was to evaluate the associations of dietary intake of total and specific phytosterols and risk of esophageal squamous cell carcinoma (ESCC) and to explore their joint effects with PLCE1 rs2274223 polymorphisms. METHODS: A population-based case-control study was conducted in a Chinese rural population and 856 eligible incident ESCC cases and 856 controls were included. A validated food frequency questionnaire was used to collect dietary consumption and PLCE1 rs2274223 polymorphisms were genotyped. Unadjusted and adjusted odds ratios (ORs) with 95% confidence interval (CI) were assessed via logistic regression model. RESULTS: When comparing the highest with lowest intake quartiles, ß-sitosterol, campesterol, stigmasterol, ß-sitostanol, campestanol, and total phytosterols were all associated with a decreased risk of ESCC, with adjusted ORs being 0.32 (95% CI 0.20-0.48), 0.18 (95% CI 0.11-0.27), 0.45 (95% CI 0.29-0.70), 0.13 (95% CI 0.08-0.20), 0.14 (95% CI 0.09-0.22) and 0.28 (95% CI 0.18-0.43), respectively. An exposure-response relationship was also observed for both total and five specific phytosterols (all P for trend < 0.001). In comparison to rs2274223 AA genotype, both GA genotype (OR: 1.47, 95% CI 1.16-1.85) and GG genotype (OR: 2.13, 95% CI 1.20-3.84) were associated with an increased risk of ESCC. However, no interaction was observed between total/specific phytosterols intake and rs2274223 polymorphisms. CONCLUSION: Higher dietary intake of total and five specific phytosterols was associated with a lower risk of ESCC, and the risk of ESCC increased with the increment of rs2274223 G allele. The negative association between phytosterols and ESCC risk was not modified by rs2274223 polymorphisms. Foods or supplements rich in phytosterols are a promising source for chemoprevention of ESCC, and still, clinical trials will be required in any specific case.

Dietary flavonoid intake and risk of esophageal squamous cell carcinoma: A population-based case-control study.

OBJECTIVES: The aim of this population-based case-control study was to investigate the association between dietary consumption of the total flavonoids, subclasses, and specific flavonoids and the risk of esophageal squamous cell carcinoma (ESCC) among adults in a high-risk area of China. METHODS: We recruited 820 ESCC participants and 863 control participants from Yanting County. Dietary flavonoids were assessed using a validated 76-item food frequency questionnaire. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using logistic regression after considering potential confounders. RESULTS: Comparing the highest and lowest intake quartiles, we observed a negative association of ESCC risk with consumption of isoflavones (OR = 0.34, 95% CI = 0.23-0.50, P for trend < 0.001), daidzein (OR = 0.31, 95% CI = 0.21-0.45, P for trend < 0.001), genistein (OR = 0.34, 95% CI = 0.23-0.50, P for trend < 0.001), and glycitein (OR = 0.32, 95% CI = 0.22-0.48, P for trend < 0.001) after adjustment for potential confounders. A more pronounced negative association was observed when comparing the third quartile, rather than the fourth, with the lowest quartile for consumption of anthocyanidins (OR = 0.58, 95% CI = 0.42-0.80, P for trend = 0.004), delphinidin (OR = 0.57, 95% CI = 0.41-0.78, P for trend = 0.004), and cyanidin (OR = 0.48, 95% CI = 0.35-0.66, P for trend = 0.003) after considering potential confounders. Consumption of total flavonoids, flavones, flavonols, and six other specific flavonoids (quercetin, myricetin, kaempferol, luteolin, apigenin, and peonidin) was not associated with ESCC risk. CONCLUSIONS: The results suggest that increased dietary intake of isoflavones and moderate consumption of anthocyanidins were associated with a decreased risk of ESCC. Future nutritional guidelines may emphasize foods or supplements rich in specific isoflavones and anthocyanidins for ESCC chemoprevention.

Green tea consumption and risk for esophageal cancer: A systematic review and dose-response meta-analysis.

OBJECTIVE: Controversial results of the association between green tea consumption and risk for esophageal cancer (EC) were reported by previous meta-analysis. Thus, the aim of this study was to quantitatively investigate the association. METHODS: The Cochrane Library, PubMed, and EMBASE databases were searched for relevant studies. We used a "one-stage approach" with a restricted cubic spline model to summarize the dose-specific relationships between green tea and risk for EC. Odds ratios (ORs) were used to measure the effects. Fourteen studies were included with a total of 5057 ECs among 493 332 participants. RESULTS: In the dose-response analysis, the summary OR for a 1 cup/d increase in green tea was 1.00 (95% confidence interval [CI], 0.95-1.04; I2 = 77%). No nonlinearity association was observed between tea consumption and risk for EC (P = 0.71 for nonlinearity). In the subgroup of sex, the summary OR for a 1 cup/d increase in green tea was 1.03 (95% CI, 0.95-1.11, I2 = 67%) for men and 0.79 (95% CI, 0.68-0.91; I2 = 0%) for women. CONCLUSION: Contrary to previous studies, based on current evidence, the present dose-response study suggested no association between green tea and risk for EC. However, there might be a protective effect of green tea in women. Notably, our conclusion might be influenced by limited studies and potential bias, such as dose of green tea assessment and select bias of case-control studies. Further larger number, prospective, and well-designed larger-scale studies are needed to provide more precise evidence, especially in women and more regions (United States and Europe).

Tea drinking and the risk of esophageal cancer: focus on tea type and drinking temperature.

The association between tea drinking and esophageal cancer is still contradictory. This study is to determine the association between tea drinking and esophageal squamous cell carcinoma focusing on drinking temperature and tea types. A population-based case-control study was conducted in a high esophageal squamous cell carcinoma risk area in China. A total of 942 incident esophageal squamous cell carcinoma cases with historical confirmation and 942 age- and sex- individually matched community controls were recruited from the study area. Trained interviewers using a structured questionnaire collected detailed information on tea drinking, diet, smoking and alcohol drinking habits. Habitual tea drinking temperature was measured with a thermometer during interviews. We analyzed the association between tea consumption, drinking temperature and esophageal squamous cell carcinoma, stratified by tea type, while adjusting for other potentially confounding factors. Drinking very hot tea (>65°C) was significantly associated with the increased risk of esophageal squamous cell carcinoma (odds ratio = 1.67, 95% confidential interval 1.25-2.24) relative to non-drinkers. Consumption of black tea, irrespective of the frequency, intensity and tea leaf amount, was significantly associated with a higher risk (P for trend <0.01). Compared to those who consumed <300 g/month tea leaves at ≤65°C, those who consumed more than 300 g/month tea leave at >65°C had a more than 1.8-fold higher risk of esophageal squamous cell carcinoma for both green tea and black tea. Our results provide more evidence that drinking very hot tea (above 65°C) are significantly associated with an increased risk of esophageal squamous cell carcinoma.

Risk Factors of Esophageal Squamous Cell Cancer Specific for Different Macroscopic Types.

Objective: To further explore risk factors of esophageal squamous cell cancer specific for different macroscopic types.Methods: A total of 423 patients and 423 age (±3 years) and gender matched controls were recruited. Multinomial logistic regression and multivariable logistic regression analysis were used to evaluate the risk factors of ESCC specific for different macroscopic types.Results: In this study, we found that drinking hot tea (OR = 1.98, 95% CI:1.14-3.43) and higher intake of hard food (OR = 1.64, 95% CI:1.05-2.58) positively associated with ulcerative type of ESCC, but not with medullary type or other types. Although alcohol drinking and lower intake of fresh vegetable appeared to be more harmful to the ulcerative-type ESCC, the discrepant risks were not significantly different in ulcerative type and medullary type. Moreover, tobacco smoking, intake of hot food, spicy food, fresh fruit, scallion and garlic were related to ESCC risk, whereas no significant difference in magnitude of their associations with respect to macroscopic type was observed. Furthermore, significant multiplicative interaction between tobacco smoking and alcohol drinking was found in ulcerative-type and medullary-type ESCC.Conclusion: Drinking hot tea and higher intake of hard food were associated with increased risk of ulcerative type of ESCC. However, the mechanism for this difference needs to be further studied.

Green Tea Consumption and Esophageal Cancer Risk: A Meta-analysis.

Background: The protective role of green tea against cancer is still unknown.Objectives: To investigate the association between green tea consumption and esophageal cancer risk through meta-analysis.Methods: We searched MEDLINE, EMBASE, Web of Science and Cochrane Library for studies on the relationship between green tea and esophageal cancer risk. We assessed heterogeneity (I2) and publication bias (Begg's and Egger's tests). Pooled relative risks (RRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random effects models.Results: A total of 20 studies were included. The RRs for all studies was 0.65 (95% CI: 0.57-0.73), with I2 = 75.3% and P = 0. In the subgroup analysis, the following variables showed marked heterogeneity: Asian (RR: 0.64; 95% CI: 0.56-0.73) and non-Asian countries (RR: 0.74; 95% CI: 0.45-1.03), female (RR: 0.55; 95% CI: 0.39-0.71) and male + female (RR: 0.64; 95% CI: 0.54-0.75), case-control study (RR: 0.62; 95% CI: 0.52-0.71), impact factor >3 (RR: 0.65; 95% CI: 0.56-0.75), impact factor <3 (RR: 0.64; 95% CI: 0.48-0.80), Newcastle-Ottawa Scale >7 (RR: 0.82; 95% CI: 0.66-0.97) and Newcastle-Ottawa Scale ≤7 (RR: 0.59; 95% CI: 0.49-0.68).Conclusion: Green tea consumption could be a protective factor for esophageal cancer.

A prospective study of tea drinking temperature and risk of esophageal squamous cell carcinoma.

Previous studies have reported an association between hot tea drinking and risk of esophageal cancer, but no study has examined this association using prospectively and objectively measured tea drinking temperature. We examined the association of tea drinking temperature, measured both objectively and subjectively at study baseline, with future risk of esophageal squamous cell carcinoma (ESCC) in a prospective study. We measured tea drinking temperature using validated methods and collected data on several other tea drinking habits and potential confounders of interest at baseline in the Golestan Cohort Study, a population-based prospective study of 50,045 individuals aged 40-75 years, established in 2004-2008 in northeastern Iran. Study participants were followed-up for a median duration of 10.1 years (505,865 person-years). During 2004-2017, 317 new cases of ESCC were identified. The objectively measured tea temperature (HR 1.41, 95% CI 1.10-1.81; for ≥60°C vs. <60°C), reported preference for very hot tea drinking (HR 2.41, 95% CI 1.27-4.56; for "very hot" vs. "cold/lukewarm"), and reported shorter time from pouring tea to drinking (HR 1.51, 95% CI 1.01-2.26; for <2 vs. ≥6 min) were all associated with ESCC risk. In analysis of the combined effects of measured temperature and amount, compared to those who drank less than 700 ml of tea/day at <60°C, drinking 700 mL/day or more at a higher-temperature (≥60°C) was consistently associated with an about 90% increase in ESCC risk. Our results substantially strengthen the existing evidence supporting an association between hot beverage drinking and ESCC.

Oolong tea consumption and its interactions with a novel composite index on esophageal squamous cell carcinoma.

BACKGROUND: No previous study has investigated the association between oolong tea consumption and esophageal squamous cell carcinoma (ESCC), we aim to elucidate the association between oolong tea consumption and ESCC and its joint effects with a novel composite index. METHODS: In a hospital-based case-control study, 646 cases of ESCC patients and 646 sex and age matched controls were recruited. A composite index was calculated to evaluate the role of demographic characteristics and life exposure factors in ESCC. Unconditional logistic regression was used to calculate the point estimates between oolong tea consumption and risk of ESCC. RESULTS: No statistically significant association was found between oolong tea consumption and ESCC (OR = 1.39, 95% CI: 0.94-2.05). However, drinking hot oolong tea associated with increased risk of ESCC (OR = 1.60, 95% Cl: 1.06-2.41). Furthermore, drinking hot oolong tea increased ESCC risk in the high-risk group (composite index> 0.55) (OR = 3.14, 95% CI: 1.93-5.11), but not in the low-risk group (composite index≤0.55) (OR = 1.16, 95% CI: 0.74-1.83). Drinking warm oolong tea did not influence the risk of ESCC. CONCLUSIONS: No association between oolong tea consumption and risk of ESCC were found, however, drinking hot oolong tea significantly increased the risk of ESCC, especially in high-risk populations.