Alcohol consumption and gastric cancer risk—A pooled analysis within the StoP project consortium

An association between heavy alcohol drinking and gastric cancer risk has been recently reported, but the issue is still open to discussion and quantification. We investigated the role of alcohol drinking on gastric cancer risk in the “Stomach cancer Pooling (StoP) Project,” a consortium of epidemiological studies. A total of 9,669 cases and 25,336 controls from 20 studies from Europe, Asia and North America were included. We estimated summary odds‐ratios (ORs) and the corresponding 95% confidence intervals (CIs) by pooling study‐specific ORs using random‐effects meta‐regression models. Compared with abstainers, drinkers of up to 4 drinks/day of alcohol had no increase in gastric cancer risk, while the ORs were 1.26 (95% CI, 1.08–1.48) for heavy (>4 to 6 drinks/day) and 1.48 (95% CI 1.29–1.70) for very heavy (>6 drinks/day) drinkers. The risk for drinkers of >4 drinks/day was higher in never smokers (OR 1.87, 95% CI 1.35–2.58) as compared with current smokers (OR 1.14, 95% CI 0.93–1.40). Somewhat stronger associations emerged with heavy drinking in cardia (OR 1.61, 95% CI 1.11–2.34) than in non‐cardia (OR 1.28, 95% CI 1.13–1.45) gastric cancers, and in intestinal‐type (OR 1.54, 95% CI 1.20–1.97) than in diffuse‐type (OR 1.29, 95% CI 1.05–1.58) cancers. The association was similar in strata of H. pylori infected (OR = 1.52, 95% CI 1.16–2.00) and noninfected subjects (OR = 1.69, 95% CI 0.95–3.01). Our collaborative pooled‐analysis provides definite, more precise quantitative evidence than previously available of an association between heavy alcohol drinking and gastric cancer risk.     

Alcohol drinking and non-Hodgkin lymphoma risk: a systematic review and a meta-analysis

BackgroundWhether an association between alcohol drinking and non-Hodgkin lymphoma (NHL) risk exists is an open question. In order to provide quantification of the issue, we carried out a meta-analysis of published data.MethodsWe identified 21 case–control and 8 cohort studies, including a total of 18 759 NHL cases. We derived meta-analytic estimates using random-effects models, taking into account correlation between estimates.ResultsThe overall relative risk (RR) of NHL for drinkers versus non-drinkers was 0.85 [95% confidence interval (CI) 0.79–0.91]. Compared with non-drinkers, the pooled RRs were 0.88 for light (≤1 drink per day), 0.87 for moderate (1 to <4 drinks per day), and 0.84 for heavy (≥4 drinks per day) alcohol drinking. There was no association for light drinkers in cohort studies, whereas for moderate and heavy drinkers, the RRs were similar in case–control (0.85 for moderate, 0.92 for heavy) and cohort (0.89 for moderate, 0.79 for heavy) studies. The inverse relation with alcohol consumption (drinkers versus non-drinkers) was similar in men (RR = 0.83) and women (RR = 0.86), but apparently stronger in studies from Asia (RR = 0.69) than other world areas (RR = 0.88).ConclusionThis meta-analysis provides quantitative evidence of a favourable role of alcohol drinking on NHL risk, though the lack of a biological explanation suggests caution in the interpretation of results.     

A meta-analysis on alcohol drinking and gastric cancer risk

BackgroundWhether an association between alcohol drinking and gastric cancer risk exists is an open question. In order to provide a definite quantification of the association between alcohol drinking and gastric cancer risk, we conducted a meta-analysis of available data.Patients and methods:We carried out a PubMed search of articles published up to June 2010 and identified 44 case–control and 15 cohort studies, including a total of 34 557 gastric cancer cases. We derived meta-analytic estimates using random-effects models, taking into account correlation between estimates. We carried out a dose–risk analysis using nonlinear random-effects meta-regression models.ResultsCompared with nondrinkers, the pooled relative risk (RR) was 1.07 [95% confidence interval (CI) 1.01–1.13] for alcohol drinkers and 1.20 (95% CI 1.01–1.44) for heavy alcohol drinkers (≥4 drinks per day). The pooled estimates were apparently higher for gastric noncardia (RR for heavy drinkers = 1.17, 95% CI 0.78–1.75) than for gastric cardia (RR = 0.99, 95% CI 0.67–1.47) adenocarcinoma. The dose–risk model estimated a RR of 0.95 (95% CI 0.91–0.99) for 10 g/day and 1.14 (95% CI 1.08–1.21) for 50 g/day.ConclusionsThis meta-analysis provides definite evidence of a lack of association between moderate alcohol drinking and gastric cancer risk. There was, however, a positive association with heavy alcohol drinking.     

Alcohol consumption and risk of hematological malignancies: A meta‐analysis of prospective studies

Current convincing evidence suggests that alcohol intake increases the risk of several carcinomas, which might subsequently lead to a recommendation toward limiting alcohol consumption. However, there are accumulating data worth meta‐analyzing that show a different effect on the risk of hematological malignancies. Eligible cohort studies were sought in PubMed database up to August 31, 2016. Separate analyses were performed by subtype of hematological malignancy (non‐Hodgkin lymphoma [NHL] and subtypes, Hodgkin lymphoma [HL], leukemia and subtypes), time status (ever, current, former), level of consumption (light, moderate, heavy), alcoholic beverage (total alcohol, beer, liquor, wine) and gender. Moderate and heavy alcohol consumption were significantly associated with reduced risk of NHL (relative risk [RR] = 0.85, 95% confidence interval [CI]: 0.80–0.90 and RR = 0.73, 95%CI: 0.60–0.89, respectively); a protective trend was also shown for light alcohol intake (RR = 0.93, 95%CI: 0.87–1.00). Specifically, beer consumption was associated with reduced NHL risk (RR = 0.88, 95%CI: 0.81–0.95). However, the association regarding other alcoholic beverages seemed null. The beneficial effects of alcohol mainly pertained to Diffuse Large B‐Cell Lymphoma (DLBCL) (RR = 0.83, 95%CI: 0.77–0.89) and Follicular Lymphoma (FL) (RR = 0.85, 95%CI: 0.78–0.93). There was also no association between alcohol consumption and risk of HL or leukemias. In contrast to most solid malignancies, alcohol seems to confer a protective effect on NHL risk, especially on DLBCL and FL subtypes, with beer being notably beneficial.     

Coffee consumption and risk of colorectal cancer: A systematic review and meta‐analysis of prospective cohort studies

An inverse association between coffee consumption and the risk of colorectal cancer has been found in several case‐control studies, but such an association was not consistent in prospective cohort studies. We conducted a systematic meta‐analysis of prospective cohort studies on coffee consumption and colorectal cancer published up to June 2008. We combined relative risks (RR) for colorectal cancer comparing high vs. low categories of coffee consumption using random‐effects models. We identified 12 eligible cohort studies, which included 646,848 participants and 5,403 cases for colorectal cancer. The summarized result of the meta‐analysis comparing high‐ vs. low‐consumption categories showed no significant effect of coffee consumption on colorectal cancer risk (RR = 0.91; 95% confidence intervals [CI]: 0.81–1.02). The RR was 0.93 (95% CI: 0.71–1.22) when considering 4 studies conducted in the United States of America, 0.91 (95% CI: 0.76–1.10) for 5 studies from Europe, and 0.83 (95% CI: 0.62–1.10) for 3 Japanese studies. No significant differences by sex and cancer‐site were found, but there was a slight suggestion of an inverse association between coffee consumption and colon cancer in women (RR = 0.79; 95% CI: 0.60–1.04), especially Japanese women (RR = 0.62; 95% CI: 0.37–1.05). The suggestive inverse associations were slightly stronger in studies that controlled for smoking and alcohol, and in studies with shorter follow‐up times. Information on coffee type, its serving size, or brewing method may provide a better understanding of this reassuring result and the real role of coffee on colorectal cancer risk. © 2008 Wiley‐Liss, Inc.     

Adherence to Mediterranean diet and risk of cancer: A systematic review and meta‐analysis of observational studies

The aim of this research study was to meta‐analyze the effects of adherence to Mediterranean diet (MD) on overall cancer risk, and different cancer types. Literature search was performed using the electronic databases MEDLINE, SCOPUS and EMBASE until January 10, 2014. Inclusion criteria were cohort or case–control studies. Study specific risk ratios (RRs) were pooled using a random effect model by the Cochrane software package Review Manager 5.2. Twenty‐one cohort studies including 1,368,736 subjects and 12 case–control studies with 62,725 subjects met the objectives and were enclosed for meta‐analyses. The highest adherence to MD category resulted in a significantly risk reduction for overall cancer mortality/incidence (cohort; RR: 0.90, 95% CI 0.86–0.95, p < 0.0001; I² = 55%), colorectal (cohort/case–control; RR: 0.86, 95% CI 0.80–0.93, p < 0.0001; I² = 62%], prostate (cohort/case–control; RR: 0.96, 95% CI 0.92–0.99, p = 0.03; I² = 0%) and aerodigestive cancer (cohort/case–control; RR: 0.44, 95% CI 0.26–0.77, p = 0.003; I² = 83%). Nonsignificant changes could be observed for breast cancer, gastric cancer and pancreatic cancer. The Egger regression tests provided limited evidence of substantial publication bias. High adherence to a MD is associated with a significant reduction in the risk of overall cancer mortality (10%), colorectal cancer (14%), prostate cancer (4%) and aerodigestive cancer (56%).     

Fruits and vegetables consumption and risk of non‐Hodgkin's lymphoma: A meta‐analysis of observational studies

Epidemiologic evidence suggests that intakes of fruits and/or vegetables may play a role in the etiology of non‐Hodgkin's lymphoma (NHL), but the findings are inconsistent. We aimed to assess fruits and/or vegetables intakes in relation to risk of NHL by a meta‐analytic approach. We searched on PubMed database from January 1966 to September 2012 to indentify case‐control and cohort studies. We used a random‐effects model to compute summary risk estimates. For vegetables, the summary relative risks (RRs) of NHL for high versus low intake for case‐control, cohort and all studies were 0.75 (95% CI, 0.60–0.94; N = 8), 0.90 (95% CI, 0.81–1.00; N = 5) and 0.81 (95%CI, 0.71–0.92; N = 13) ; and the corresponding RRs for intake of 1 serving per day were 0.88 (95% CI, 0.80–0.96; N = 8), 0.96 (95% CI, 0.92–1.00; N = 5) and 0.92 (95%CI, 0.87–0.96; N = 13). For fruits and vegetables combined, the summary RR for high versus low intake was 0.78 (95%CI, 0.66–0.92; N = 4), and for intake of 1 serving per day was 0.95 (95%CI, 0.91–1.00; N = 4). Regarding histological subtypes, vegetables intake was significantly inversely associated with diffuse large B‐cell lymphoma and follicular lymphoma, but not small lymphocytic lymphoma/chronic lymphocytic leukemia (high vs. low intake, RR = 0.70, 0.70 and 1.01, respectively; N = 7, 7 and 10, respectively). Fruits intake was generally not associated with total NHL, or any histological subtypes. Our findings suggest that intakes of vegetables, and fruits and vegetables combined, but not fruits alone, significantly reduce risk of NHL.     

Alcohol consumption,finasteride, and prostate cancer risk

BACKGROUND:

Current research is inconclusive regarding the relation between alcohol consumption and prostate cancer risk. In this study, the authors examined the associations of total alcohol, type of alcoholic beverage, and drinking pattern with the risk of total, low‐grade, and high‐grade prostate cancer.

METHODS:

Data for this study came from the 2129 participants in the Prostate Cancer Prevention Trial (PCPT) who had cancer detected during the 7‐year trial and 8791 men who were determined by biopsy to be free of cancer at the trial end. Poisson regression was used to calculate relative risks (RRs) and 95% confidence intervals (95% CIs) for associations of alcohol intake with prostate cancer risk.

RESULTS:

Associations of drinking with high‐grade disease did not differ by treatment arm. In combined arms, heavy alcohol consumption (≥50 g of alcohol daily) and regular heavy drinking (≥4 drinks daily on ≥5 days per week) were associated with increased risks of high‐grade prostate cancer (RR, 2.01 [95% CI, 1.33‐3.05] and 2.17 [95% CI, 1.42‐3.30], respectively); less heavy drinking was not associated with risk. Associations of drinking with low‐grade cancer differed by treatment arm. In the placebo arm, there was no association of drinking with risk of low‐grade cancer. In the finasteride arm, drinking ≥50 g of alcohol daily was associated with an increased risk of low‐grade disease (RR, 1.89; 95% CI, 1.39‐2.56); this finding was because of a 43% reduction in the risk of low‐grade cancer attributable to finasteride treatment in men who drank <50g of alcohol daily and the lack of an effect of finasteride in men who drank ≥50 g of alcohol daily (P_interaction = .03).

CONCLUSIONS:

Heavy, daily drinking increased the risk of high‐grade prostate cancer. Heavy drinking made finasteride ineffective for reducing prostate cancer risk. Cancer 2009. © 2009 American Cancer Society.     

Alcohol drinking and colorectal cancer risk: an overall and dose–response meta-analysis of published studies

BackgroundThe International Agency for Research on Cancer (IARC) concluded that alcohol consumption is related to colorectal cancer (CRC). However, several issues remain unresolved, including quantification of the association for light (≤1 drink/day) and moderate (2–3 drinks/day) alcohol drinking, investigation of the dose–response relationship, and potential heterogeneity of effects by sex, colorectal site, and geographical region.MethodsTwenty-seven cohort and 34 case–control studies presenting results for at least three categories of alcohol intake were identified from a PubMed search of articles published before May 2010. The summary relative risks (RRs) were estimated by the random effects model. Second-order fractional polynomials and random effects meta-regression models were used for modeling the dose–risk relation.ResultsThe RRs were 1.21 [95% confidence interval (CI) 1.13–1.28] for moderate and 1.52 (95% CI 1.27–1.81) for heavy (≥4 drinks/day) alcohol drinking. The RR for moderate drinkers, compared with non-/occasional drinkers, was stronger for men (RR = 1.24, 95% CI 1.13–1.37) than for women (RR = 1.08, 95% CI 1.03–1.13; P_{heterogeneity} = 0.02). For heavy drinkers, the association was stronger in Asian studies (RR = 1.81, 95% CI 1.33–2.46; P_{heterogeneity} = 0.04). The dose–risk analysis estimated RRs of 1.07 (95% CI 1.04–1.10), 1.38 (95% CI 1.28–1.50), and 1.82 (95% CI 1.41–2.35) for 10, 50, and 100 g/day of alcohol, respectively.ConclusionsThis meta-analysis provides strong evidence for an association between alcohol drinking of >1 drink/day and colorectal cancer risk.     

Association between height and thyroid cancer risk: A meta‐analysis of prospective cohort studies

While several epidemiological studies have investigated the relationship between height and risk for thyroid cancer, the results were inconsistent. In the present study, a systematic review and meta‐analysis of prospective cohort studies was conducted to assess the impact of height on thyroid cancer risk. Online databases were searched up to December 30, 2014, for prospective cohort studies on the association between height and thyroid cancer risk. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated using a random‐effects model of meta‐analysis. In all, 11 articles were included in this meta‐analysis, including 15 prospective cohort studies, containing 6,695,593 participants and 7,062 cases of thyroid cancer. By comparing the highest versus the lowest categories of height, we reported that risk of thyroid cancer was increased with height in both men (summary RR = 1.40, 95%CI 1.09–1.78, p = 0.008) and women (summary RR = 1.54, 95%CI 1.30–1.83, p < 0.001). The summary RR of thyroid cancer per 5‐cm increase in height was 1.16 (95%CI 1.09–1.23, p < 0.001). The results were similar among men (per 5‐cm increase RR = 1.13, 95%CI 1.03–1.23, p = 0.011) and women (per 5‐cm increase RR = 1.18, 95%CI 1.10–1.27, p < 0.001). No obvious risk of publication bias was observed. Our meta‐analysis provides strong evidence for a dose–response relationship between height and risk of thyroid cancer in both men and women.     

Patterns of alcohol consumption and breast cancer risk in the California Teachers Study cohort.

Alcohol consumption of approximately two drinks or more per day has been associated with elevated breast cancer risk in the California Teachers Study cohort as well as in many other populations. The objective of this analysis is to examine effects of age at drinking and drinking patterns and to identify effect modifiers. Of the 103,460 at-risk cohort members, age <85, who resided in California and completed the baseline alcohol assessment, 1,742 were diagnosed with invasive breast cancer after joining the cohort and before January 2001. Incident breast cancers were identified through the California Cancer Registry and follow-up for death and confirmation of continued California residence used various sources. Multivariate Cox proportional hazards regression models were used to estimate relative risks (RRs). Elevated breast cancer risk was most evident for recent drinking [RR = 1.28, 95% confidence interval (CI): 1.06-1.54 for >/=20 g/day versus nondrinkers], with no clear pattern for consumption during earlier periods of life. This elevation in risk was 32% among postmenopausal women (95% CI: 1.06-1.63) and 21% among pre/perimenopausal women (95% CI: 0.76-1.92). Highest risks associated with heavy alcohol consumption were observed among postmenopausal women with a history of biopsy-diagnosed benign breast disease (RR = 1.97, 95% CI: 1.39-2.79 compared to nondrinkers without benign breast disease) or who had used combination hormone replacement therapy (HRT) (RR = 2.24, 95% CI: 1.59-3.14 compared to nondrinkers who never used HRT). Recent alcohol consumption equivalent to two or more drinks per day increases the risk of invasive breast cancer, with the greatest RRs observed among heavy drinkers who are also postmenopausal and have a history of benign breast disease or who use HRT.     

Dietary supplement use and colorectal cancer risk: A systematic review and meta‐analyses of prospective cohort studies

Use of dietary supplements is rising in countries where colorectal cancer is prevalent. We conducted a systematic literature review and meta‐analyses of prospective cohort studies on dietary supplement use and colorectal cancer risk. We identified relevant studies in Medline, Embase and Cochrane up to January 2013. Original and peer‐reviewed papers on dietary supplement use and colorectal cancer, colon cancer, or rectal cancer incidence were included. “Use‐no use”(U‐NU), “highest‐lowest”(H‐L) and “dose‐response”(DR) meta‐analyses were performed. Random‐effects models were used to estimate summary estimates. In total, 24 papers were included in the meta‐analyses. We observed inverse associations for colorectal cancer risk and multivitamin (U‐NU: RR = 0.92; 95% CI: 0.87,0.97) and calcium supplements (U‐NU: RR = 0.86; 95% CI: 0.79,0.95; H‐L: RR = 0.80; 95% CI: 0.70,0.92; DR: for an increase of 100 mg/day, RR = 0.96; 95% CI: 0.94,0.99). Inconsistent associations were found for colon cancer risk and supplemental vitamin A and vitamin C, and for colorectal cancer risk and supplemental vitamin D, vitamin E, garlic and folic acid. Meta‐analyses of observational studies suggest a beneficial role for multivitamins and calcium supplements on colorectal cancer risk, while the association with other supplements and colorectal cancer risk is inconsistent. Residual confounding of lifestyle factors might be present. Before recommendations can be made, an extensive assessment of dietary supplement use and a better understanding of underlying mechanisms is needed.     

Alcohol drinking and bladder cancer risk: a meta-analysis

BackgroundWe aimed at investigating the risk of bladder cancer at different levels of alcohol consumption by conducting a meta-analysis of epidemiological studies.Patients and methodsIn October 2010, we carried out a systematic literature search in the Medline database, using PubMed. We identified 16 case–control and 3 cohort studies, including a total of 11 219 cases of bladder cancer, satisfying the inclusion criteria for this meta-analysis. Moderate alcohol intake was defined as <3 drinks per day (i.e. <37.5 g of ethanol per day) and heavy intake as ≥3 drinks/day. Pooled estimates of the relative risks (RR) and the corresponding 95% confidence intervals (CI) were calculated using random effects models.ResultsCompared with non-drinkers, the pooled RRs of bladder cancer were 1.00 (95% CI 0.92–1.09) for moderate and 1.02 (95% CI 0.78–1.33) for heavy alcohol drinkers. When we excluded four studies that did not adjust for tobacco smoking, the corresponding estimates were 0.98 (95% CI 0.89–1.07) and 0.97 (95% CI 0.72–1.31).ConclusionsThis meta-analysis of epidemiological studies provides definite evidence on the absence of any material association between alcohol drinking and bladder cancer risk, even at high levels of consumption.     

Meat subtypes and their association with colorectal cancer: Systematic review and meta‐analysis

Associations between specific red meat subtypes and risk of colorectal cancer (CRC) have been investigated in a number of epidemiological studies. However, no publication to date has summarised the overall epidemiological evidence. We conducted a systematic review and meta‐analysis of prospective studies (cohort, nested case‐control or case‐cohort studies), which reported relative risk (RR) estimates and 95% confidence intervals (CI) for the association between intake of meat subtypes with colorectal, colon or rectal cancer or colorectal adenoma risk. PubMed and ISI Web of Science were searched up until August 1, 2014. Nineteen studies examined meat subtypes (5 beef, 5 pork, 2 lamb, 1 veal and 19 poultry) and associations with colorectal, colon or rectal cancer risk and 4 studies examined associations with adenoma risk (1 beef and 4 poultry). Comparing highest versus lowest intake, beef consumption was associated with an increased risk of CRC (RR = 1.11, 95% CI = 1.01 to 1.22) and colon cancer (RR = 1.24, 95% CI = 1.07 to 1.44), but no association was found with rectal cancer (RR = 0.95, 95% CI = 0.78 to 1.16). Higher consumption of lamb was also associated with increased risk of CRC (RR = 1.24, 95% CI = 1.08 to 1.44). No association was observed for pork (RR = 1.07, 95% CI = 0.90 to 1.27), but some between study heterogeneity was observed. No association was observed for poultry consumption and risk of colorectal adenomas or cancer. This meta‐analysis suggests that red meat subtypes differ in their association with CRC and its sub sites. Further analysis of data from prospective cohort studies is warranted, especially regarding the role of pork.     

Dietary acrylamide and cancer risk: An updated meta‐analysis

The debate on the potential carcinogenic effect of dietary acrylamide is open. In consideration of the recent findings from large prospective investigations, we conducted an updated meta‐analysis on acrylamide intake and the risk of cancer at several sites. Up to July 2014, we identified 32 publications. We performed meta‐analyses to calculate the summary relative risk (RR) of each cancer site for the highest versus lowest level of intake and for an increment of 10 µg/day of dietary acrylamide, through fixed‐effects or random‐effects models, depending on the heterogeneity test. Fourteen cancer sites could be examined. No meaningful associations were found for most cancers considered. The summary RRs for high versus low acrylamide intake were 0.87 for oral and pharyngeal, 1.14 for esophageal, 1.03 for stomach, 0.94 for colorectal, 0.93 for pancreatic, 1.10 for laryngeal, 0.88 for lung, 0.96 for breast, 1.06 for endometrial, 1.12 for ovarian, 1.00 for prostate, 0.93 for bladder and 1.13 for lymphoid malignancies. The RR was of borderline significance only for kidney cancer (RR = 1.20; 95% confidence interval, CI, 1.00–1.45). All the corresponding continuous estimates ranged between 0.95 and 1.03, and none of them was significant. Among never‐smokers, borderline associations with dietary acrylamide emerged for endometrial (RR = 1.23; 95% CI, 1.00–1.51) and ovarian (RR = 1.39; 95% CI, 0.97–2.00) cancers. This systematic review and meta‐analysis of epidemiological studies indicates that dietary acrylamide is not related to the risk of most common cancers. A modest association for kidney cancer, and for endometrial and ovarian cancers in never smokers only, cannot be excluded.     

Calcium intake and colorectal adenoma risk: Dose‐response meta‐analysis of prospective observational studies

Evidence from randomized controlled trials suggests that calcium may protect against recurrence of colorectal adenomas, which could lead to the subsequent prevention of cancer. Yet the trials used only a large single dose and were of small sizes, and thus, knowledge of the dose‐response relationship and influence on high‐risk adenomas is limited. To address these issues, we conducted linear and nonlinear dose‐response meta‐analyses primarily based on prospective observational studies published up to July 2014 identified from PubMed and Embase. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated for total and supplemental calcium intake, respectively, using a random‐effects model. For total calcium intake, summary RR for each 300 mg/day increase was 0.95 (95% CI = 0.92–0.98; I² = 45%; eight studies with 11,005 cases; range of intake = 333–2,229 mg/day). Evidence of nonlinearity was indicated: approximately, compared to 550 mg/day of total calcium intake, the summary RR was 0.92 (95% CI = 0.89–0.94) at 1,000 mg/day and 0.87 (95% CI = 0.84–0.90) at 1,450 mg/day (p_nonlinearity < 0.01). Associations were stronger for high‐risk adenomas (≥1 cm in diameter, (tubulo)villous histology, dysplasia, or multiplicity): approximately, compared to 550 mg/day of total calcium intake, the summary RR was 0.77 (95% CI = 0.74–0.81) at 1,000 mg/day and reduced to 0.69 (95% CI = 0.66–0.73) at 1,450 mg/da (p_nonlinearity < 0.01). For supplemental calcium intake, summary RR of total adenoma risk for each 300 mg/day increase was 0.96 (95% CI = 0.93–0.99; I² = 0%; three studies with 4,548 cases; range of supplementation = 0–1,366 mg/day). In conclusion, calcium intake may continue to decrease the risk of adenomas, particularly high‐risk adenomas, over a wide range of calcium intake.     

Alcohol consumption and cigarette smoking in combination: A predictor of contralateral breast cancer risk in the WECARE study

Alcohol drinking and, to a lesser extent, cigarette smoking are risk factors for a first primary breast cancer. Information on these behaviours at diagnosis may contribute to risk prediction of contralateral breast cancer (CBC) and they are potentially modifiable. The WECARE Study is a large population‐based case‐control study of women with breast cancer where cases (N = 1,521) had asynchronous CBC and controls (N = 2,212), matched on survival time and other factors, had unilateral breast cancer (UBC). Using multivariable conditional logistic regression to estimate rate ratios (RR) and 95% confidence intervals (CI), we examined the risk of CBC in relation to drinking and smoking history at and following first diagnosis. We adjusted for treatment, disease characteristics and other factors. There was some evidence for an association between CBC risk and current drinking or current smoking at the time of first breast cancer diagnosis, but the increased risk occurred primarily among women exposed to both (RR = 1.62, 95% CI 1.24–2.11). CBC risk was also elevated in women who both smoked and drank alcohol after diagnosis (RR = 1.54, 95% CI 1.18–1.99). In the subset of women with detailed information on amount consumed, smoking an average of ≥10 cigarettes per day following diagnosis was also associated with increased CBC risk (RR = 1.50, 95% CI 1.08–2.08; p‐trend = 0.03). Among women with a diagnosis of breast cancer, information on current drinking and smoking could contribute to the prediction of CBC risk. Women who both drink and smoke may represent a group who merit targeted lifestyle intervention to modify their risk of CBC.     

Age at menarche and risk of ovarian cancer: A meta‐analysis of epidemiological studies

Epidemiological studies have reported inconsistent associations between menarcheal age and ovarian cancer risk. To our knowledge, a meta‐analysis for the association between menarcheal age and ovarian cancer has not been reported. Relevant published studies of menarcheal age and ovarian cancer were identified using MEDLINE, EMBASE and Web of Science through the end of April 2012. Two authors (T‐T.G. and Q‐J.W.) independently assessed eligibility and extracted data. We pooled the relative risks (RRs) from individual studies using a random‐effects model and performed heterogeneity and publication bias analyses. A total of 27 observational studies consisting of 22 case–control and five cohort studies were included in our analysis. In a pooled analysis of all studies, a statistically significant inverse association was observed between menarcheal age (for the oldest compared to the youngest category) and ovarian cancer risk (RR = 0.85; 95% confidence interval [CI] = 0.75–0.97). The pooled RRs of ovarian cancer for the oldest versus the youngest categories of menarcheal age in prospective and case–control studies were 0.89 (95% CI = 0.76–1.03) and 0.84 (95% CI = 0.70–0.99), respectively. Inverse associations between menarcheal age and ovarian cancer risk were observed in most subgroups; however, the significant association was restricted to invasive and borderline serous ovarian cancer. In conclusion, findings from this meta‐analysis support that menarcheal age was inversely associated with the risk of ovarian cancer. More large studies are warranted to stratify these results by different cancer grading and histotype of ovarian cancer.     

A meta-analysis on alcohol drinking and esophageal and gastric cardia adenocarcinoma risk

BackgroundIn order to provide a precise quantification of the association between alcohol drinking and esophageal and gastric cardia adenocarcinoma risk, we conducted a meta-analysis of available data.Patients and methodsWe identified 20 case–control and 4 cohort studies, including a total of 5500 cases. We derived meta-analytic estimates using random-effects models, taking into account correlation between estimates, and we carried out a dose–risk analysis using nonlinear random-effects meta-regression models.ResultsThe relative risk (RR) for drinkers versus nondrinkers was 0.96 [95% confidence interval (CI) 0.85–1.09] overall, 0.87 (95% CI 0.74–1.01) for esophageal adenocarcinoma and 0.89 (95% CI 0.76–1.03) for gastric cardia adenocarcinoma. Compared with nondrinkers, the pooled RRs were 0.86 for light (≤1 drink per day), 0.90 for moderate (1 to <4 drinks per day), and 1.16 for heavy (≥4 drinks per day) alcohol drinking. The dose–risk model found a minimum at 25 g/day, and the curve was <1 up to 70 g/day.ConclusionsThis meta-analysis provides definite evidence of an absence of association between alcohol drinking and esophageal and gastric cardia adenocarcinoma risk, even at higher doses of consumption.     

Analgesic use and the risk of kidney cancer: A meta‐analysis of epidemiologic studies

Analgesics are the most commonly used over‐the‐counter drugs worldwide with certain analgesics having cancer prevention effect. The evidence for an increased risk of developing kidney cancer with analgesic use is mixed. Using a meta‐analysis design of available observational epidemiologic studies, we investigated the association between analgesic use and kidney cancer risk. We searched the MEDLINE and EMBASE databases to identify eligible case–control or cohort studies published in English until June 2012 for three categories of analgesics: acetaminophen, aspirin or other non‐steroidal anti‐inflammatory drugs (NSAIDs). Study‐specific effect estimates were pooled to compute an overall relative risk (RR) and its 95% confidence interval (CI) using a random‐effects model for each category of the analgesics. We identified 20 studies (14 with acetaminophen, 13 with aspirin and five with other NSAIDs) that were performed in six countries, including 8,420 cases of kidney cancer. Use of acetaminophen and non‐aspirin NSAIDs were associated with an increased risk of kidney cancer (pooled RR: 1.28; 95% CI: 1.15–1.44 and 1.25; 95% CI: 1.06–1.46, respectively). For aspirin use, we found no overall increased risk (pooled RR: 1.10; 95% CI: 0.95–1.28), except for non‐US studies (five studies, pooled RR: 1.17; 95% CI: 1.04–1.33). Similar increases in risks were seen with higher analgesic intake. In this largest meta‐analysis to date, we found that acetaminophen and non‐aspirin NSAIDs are associated with a significant risk of developing kidney cancer. Further work is needed to elucidate biologic mechanisms behind these findings.