Alcohol intake and ovarian cancer risk: a pooled analysis of 10 cohort studies

Alcohol consumption and cancer incidence in women: interaction with smoking, body mass index and menopausal hormone therapy

BACKGROUND

Alcohol consumption has been associated with increased risks of certain site-specific cancers and decreased risks of some other cancers. There is, however, little reliable evidence as to whether the alcohol-associated risks for specific cancers are modified by smoking, body mass index (BMI) and menopausal hormone therapy (MHT) use.

METHODS

In the prospective UK Million Women Study, 1,233,177 postmenopausal women without prior cancer, mean age 56 (SD 5) years, reported their alcohol consumption in median year 1998 (IQR 1998-1999), and were followed by record-linkage for incident cancer. 438,056 women who drank no alcohol or < 1 drink/week were excluded. Cox regression yielded adjusted relative risks (RRs) and 95% confidence intervals (CIs) for 21 cancers by alcohol amount; statistical significance of interactions with smoking, BMI and MHT use was assessed after allowing for multiple testing.

RESULTS

In 795,121 participants, mean consumption was 6.7 (SD 6.4) alcoholic drinks/week. During 17 (SD 5) years of follow-up, 140,203 incident cancers were recorded. There was strong evidence for a substantial association between alcohol intake and risk of upper aero-digestive cancers (oesophageal squamous cell carcinoma, oral cavity, pharynx and larynx; RR per 1 drink/day = 1.38 [95% CI 1.31-1.46]). There was also strong evidence for more moderate positive associations with breast, colorectal and pancreatic cancer (RRs per 1 drink/day = 1.12 [1.10-1.14], 1.10 [1.07-1.13], 1.08 [1.02-1.13] respectively), and moderate negative associations with thyroid cancer, non-Hodgkin's lymphoma, renal cell carcinoma and multiple myeloma (RRs per 1 drink/day = 0.79 [0.70-0.89], 0.91 [0.86-0.95], 0.88 [0.83-0.94], 0.90 [0.84-0.97] respectively). Significant interactions between alcohol and smoking were seen for upper aero-digestive cancers (RRs per 1 drink/day = 1.66 [1.54-1.79], 1.23 [1.11-1.36], 1.12 [1.01-1.25] in current, past, and never smokers respectively). BMI and MHT did not significantly modify any alcohol-associated risks.

CONCLUSIONS

These findings provide robust evidence that greater alcohol intake, even within relatively moderate ranges, increases the risk of cancers of the aerodigestive tract, breast, colorectal and pancreatic cancer, and probably decreases the risk of thyroid cancer, non-Hodgkin's lymphoma, renal cell carcinoma and multiple myeloma. Associations of alcohol intake with cancer risk were not modified by MHT use, adiposity or smoking, except in the case of upper aero-digestive cancers, where the alcohol-associated risk was largely confined to smokers.

Alcohol intake and the risk of epithelial ovarian cancer

PURPOSE

To investigate the association between alcohol intake over the lifetime and the risk of overall, borderline, and invasive ovarian cancer.

METHODS

In a population-based case-control study of 495 cases and 902 controls, conducted in Montreal, Canada, average alcohol intake over the lifetime and during specific age periods were computed from a detailed assessment of the intake of beer, red wine, white wine and spirits. Multivariable logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the association between alcohol intake and ovarian cancer risk.

RESULTS

For each one drink/week increment in average alcohol intake over the lifetime, the adjusted OR (95% CI) was 1.06 (1.01-1.10) for ovarian cancer overall, 1.13 (1.06-1.20) for borderline ovarian cancers and 1.02 (0.97-1.08) for invasive ovarian cancers. This pattern of association was similarly observed for alcohol intake in early (15- < 25 years), mid (25- < 40 years) and late adulthood (≥ 40 years), as well as for the intake of specific alcohol beverages over the lifetime.

CONCLUSIONS

Our results support the hypothesis that a higher alcohol intake modestly increases the risk of overall ovarian cancer, and more specifically, borderline tumours.

Utility of Matrix Metalloproteinases in the Diagnosis, Monitoring and Prognosis of Ovarian Cancer Patients

Ovarian cancer is one of the most common gynecologic malignancies. It is characterized by a high mortality rate, which is mainly due to the asymptomatic course of the disease. In light of the high mortality rate and increasing morbidity, new diagnostic methods are being explored to enable earlier detection, better monitoring, and improved prognosis. Such diagnostic methods include the assessment of tumor markers in various biological samples. Among the markers currently being investigated, extracellular matrix metalloproteinases (MMPs) are of particular interest. The objective of this article was to compile the existing knowledge of MMPs in ovarian cancer patients and to describe their potential diagnostic utility. Additionally, this article provides an overview of the symptoms, complications, and risk factors associated with ovarian cancer and the role of MMPs in physiology and pathology. Preliminary results indicate that tissue expression and blood and body fluid levels of MMPs may be different in ovarian cancer patients than in healthy women. The expression and concentration of individual MMPs have been shown to be correlated with cancer stage and disease severity. In addition, the preliminary value of some of these enzymes in predicting prognosis is discussed. However, as the amount of data is limited, more studies are needed to fully evaluate the potential function of individual MMPs in ovarian cancer patients. Based on the knowledge gathered for this article, it seems that MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-13, are tentatively the most useful. A thorough evaluation of their utility as modern biomarkers in ovarian cancer requires further investigation.

Associations between Low to Moderate Consumption of Alcoholic Beverage Types and Health Outcomes: A Systematic Review

Aims

There is limited research comparing light to moderate wine, beer and spirits consumption and their impact on long-term health. This systematic review aims to investigate the studies published in the past 10 years and qualitatively assess the similarities and differences between the three main beverages, when consumed at a low to moderate level, for their associations with various health outcomes.

Methods

A systematic search was conducted for comparative studies published in English language (2010 to mid-2021) of beverage-specific low to moderate alcohol consumption associated with all-cause mortality, cancer, cardiovascular disease and diabetes mellitus type II.

Results

The search yielded a total of 24 studies (8 meta-analyses; 15 prospective studies and 1 pooled analysis). Overall, most studies showed similar associations of different alcoholic beverages with chronic conditions, including all-cause mortality, many types of cancer, cardiovascular disease and diabetes mellitus type II. Not all data are consistent. Some studies show more beneficial or detrimental effects of wine than other beverage types, whereas other studies show such effects for other beverages.

Conclusion

Moderate consumption of one specific alcoholic beverage (wine, beer or spirits) may not be consistently associated with higher or lower risks for common health outcomes as compared with moderate consumption of any of the other alcoholic beverages.

Evaluating the role of alcohol consumption in breast and ovarian cancer susceptibility using population-based cohort studies and two-sample Mendelian randomization analyses

Alcohol consumption is correlated positively with risk for breast cancer in observational studies, but observational studies are subject to reverse causation and confounding. The association with epithelial ovarian cancer (EOC) is unclear. We performed both observational Cox regression and two-sample Mendelian randomization (MR) analyses using data from various European cohort studies (observational) and publicly available cancer consortia (MR). These estimates were compared to World Cancer Research Fund (WCRF) findings. In our observational analyses, the multivariable-adjusted hazard ratios (HR) for a one standard drink/day increase was 1.06 (95% confidence interval [CI]; 1.04, 1.08) for breast cancer and 1.00 (0.92, 1.08) for EOC, both of which were consistent with previous WCRF findings. MR ORs per genetically predicted one standard drink/day increase estimated via 34 SNPs using MR-PRESSO were 1.00 (0.93, 1.08) for breast cancer and 0.95 (0.85, 1.06) for EOC. Stratification by EOC subtype or estrogen receptor status in breast cancers made no meaningful difference to the results. For breast cancer, the CIs for the genetically derived estimates include the point-estimate from observational studies so are not inconsistent with a small increase in risk. Our data provide additional evidence that alcohol intake is unlikely to have anything other than a very small effect on risk of EOC.

Association between dietary intake and risk of ovarian cancer: a systematic review and meta-analysis

PURPOSE

It is unclear how dietary intake influences the ovarian cancer. The present paper sets out to systematically review and meta-analyze research on dietary intake to identify cases having high- or low-risk ovarian cancer.

METHODS

Scopus, PubMed, and Wiley Online Libraries were searched up to the date November 24, 2019. Two reviewers were requested to independently extract study characteristics and to assess the bias and applicability risks with reference to the study inclusion criteria. Meta-analyses were performed to specify the relationship between dietary intake and the risk of ovarian cancer identifying 97 cohort studies.

RESULTS

No significant association was found between dietary intake and risk of ovarian cancer. The results of subgroup analyses indicated that green leafy vegetables (RR = 0.91, 95%, 0.85-0.98), allium vegetables (RR = 0.79, 95% CI 0.64-0.96), fiber (RR = 0.89, 95% CI 0.81-0.98), flavonoids (RR = 0.83, 95% CI 0.78-0.89) and green tea (RR = 0.61, 95% CI 0.49-0.76) intake could significantly reduce ovarian cancer risk. Total fat (RR = 1.10, 95% CI 1.02-1.18), saturated fat (RR = 1.11, 95% CI 1.01-1.22), saturated fatty acid (RR = 1.19, 95% CI 1.04-1.36), cholesterol (RR = 1.13, 95% CI 1.04-1.22) and retinol (RR = 1.14, 95% CI 1.00-1.30) intake could significantly increase ovarian cancer risk. In addition, acrylamide, nitrate, water disinfectants and polychlorinated biphenyls were significantly associated with an increased risk of ovarian cancer.

CONCLUSION

These results could support recommendations to green leafy vegetables, allium vegetables, fiber, flavonoids and green tea intake for ovarian cancer prevention.

Alcohol consumption and risk of breast and ovarian cancer: A Mendelian randomization study

BACKGROUND

Alcohol consumption has been found to increase the risk of breast cancer in observation studies, yet it remains unknown if alcohol is related to other hormone-dependent cancers such as ovarian cancer. No Mendelian randomization (MR) studies have been performed to assess a potential causal relationship between alcohol use and risk of breast and ovarian cancer.

METHODS

We aim to determine if alcohol consumption is causally associated with the risk of female hormone-dependent cancers, by using summary level genetic data from the hitherto largest genome-wide association studies (GWAS) conducted on alcohol consumption (N=~1.5 million individuals), breast (N_case=122,977) and ovarian cancer (N_case=25,509). We examined three different alcohol intake exposures, drinks per week (drinks/week), alcohol use disorder (AUD) and age-adjusted alcohol use disorder identification test (AUDIT-C), to reflect the general and harmful drinking behavior. We constructed updated and stronger instruments using ninety-nine drinks/week-related SNPs, nine AUD-related SNPs and thirteen AUDIT-C-related SNPs and estimated the causal relationship applying several two-sample MR methods.

RESULTS

We did not find any evidence to support for a causal association between alcohol consumption and risk of breast cancer [OR_drinks/week=1.01 (0.85-1.21), P=0.89; OR_AUD=1.04 (95%CI: 0.89-1.21), P=0.62; OR_AUDIT-C=1.07 (0.90-1.28), P=0.44]; neither with its subtypes including ER-positive and ER-negative breast cancer, using any of the three alcohol-related exposures. For ovarian cancer, however, we identified a reduced risk with alcohol consumption, where a borderline significance was found for AUDIT-C but not for drinks/week or AUC [OR_drinks/week=0.83 (0.63-1.10), P=0.19; OR_AUD=0.92 (0.83-1.01), P=0.08; OR_AUDIT-C=0.83 (0.71-0.97), P=0.02]. The effect attenuated to null excluding SNPs associated with potential confounders [OR_drinks/week=0.81(0.53-1.21), P=0.31; OR_AUD=0.96(0.78-1.18), P=0.68; OR_AUDIT-C=0.89(0.68-1.16), P=0.38].

CONCLUSION

We do not find any compelling evidence in support for a causal relationship between genetically predicted alcohol consumption and risk of breast or ovarian cancer, consistent across three different alcohol-related exposures. Future MR studies validating our findings are needed, when large-scale alcohol consumption GWAS results become available.

Ovarian cancer: epidemiology and risk factors

The present overview of ovarian cancer epidemiology summarizes the main results for a network of case-control studies in Italy and from the Collaborative Group on Epidemiological Studies of Ovarian Cancer. There are consistent inverse relations between parity, oral contraceptive use and the risk of ovarian cancer. For other menstrual and hormonal factors (i.e. early age at menarche and late menopause), there are established associations, but of limited impact on ovarian cancer incidence on a population level. Serous and endometrioid ovarian cancers (but not mucinous or clear cell types) are related to current and recent use of hormone replacement therapy in menopause. There are no strong associations with alcohol and tobacco overall, but a direct link for tobacco with (borderline) mucinous cancers, of limited impact, however, on overall ovarian cancer mortality. There are direct associations of ovarian cancer risk with height and BMI, as well as possible relations with selected dietary factors - in the absence, however, of consistent findings - and a possible inverse association with physical activity. There is a strong association with a family history of ovarian cancer (and a few selected other neoplasms, including colorectum and endometrium). Recognized risk factors explain only a limited proportion of ovarian cancer cases on a population level. A key reason for the recent favourable trends of ovarian cancer incidence and mortality in several high-income countries is the widespread use of oral contraceptive in the generations born after 1930.

Ovarian cancer risk, ALDH2 polymorphism and alcohol drinking: Asian data from the Ovarian Cancer Association Consortium

The aldehyde dehydrogenase 2 (ALDH2) polymorphism rs671 (Glu504Lys) causes ALDH2 inactivation and adverse acetaldehyde exposure among Asians, but little is known of the association between alcohol consumption and rs671 and ovarian cancer (OvCa) in Asians. We conducted a pooled analysis of Asian ancestry participants in the Ovarian Cancer Association Consortium. We included seven case-control studies and one cohort study comprising 460 invasive OvCa cases, 37 borderline mucinous OvCa and 1274 controls of Asian descent with information on recent alcohol consumption. Pooled odds ratios (OR) with 95% confidence intervals (CI) for OvCa risk associated with alcohol consumption, rs671 and their interaction were estimated using logistic regression models adjusted for potential confounders. No significant association was observed for daily alcohol intake with invasive OvCa (OR comparing any consumption to none = 0.83; 95% CI = 0.58-1.18) or with individual histotypes. A significant decreased risk was seen for carriers of one or both Lys alleles of rs671 for invasive mucinous OvCa (OR = 0.44; 95% CI = 0.20-0.97) and for invasive and borderline mucinous tumors combined (OR = 0.48; 95% CI = 0.26-0.89). No significant interaction was observed between alcohol consumption and rs671 genotypes. In conclusion, self-reported alcohol consumption at the quantities estimated was not associated with OvCa risk among Asians. Because the rs671 Lys allele causes ALDH2 inactivation leading to increased acetaldehyde exposure, the observed inverse genetic association with mucinous ovarian cancer is inferred to mean that alcohol intake may be a risk factor for this histotype. This association will require replication in a larger sample.

Mediation analysis of alcohol consumption, DNA methylation, and epithelial ovarian cancer

Epigenetic factors and consumption of alcohol, which suppresses DNA methylation, may influence the development and progression of epithelial ovarian cancer (EOC). However, there is a lack of understanding whether these factors interact to affect the EOC risk. In this study, we aimed to gain insight into this relationship by identifying leukocyte-derived DNA methylation markers acting as potential mediators of alcohol-associated EOC. We implemented a causal inference test (CIT) and the VanderWeele and Vansteelandt multiple mediator model to examine CpG sites that mediate the association between alcohol consumption and EOC risk. We modified one step of the CIT by adopting a high-dimensional inference procedure. The data were based on 196 cases and 202 age-matched controls from the Mayo Clinic Ovarian Cancer Case-Control Study. Implementation of the CIT test revealed two CpG sites (cg09358725, cg11016563), which represent potential mediators of the relationship between alcohol consumption and EOC case-control status. Implementation of the VanderWeele and Vansteelandt multiple mediator model further revealed that these two CpGs were the key mediators. Decreased methylation at both CpGs was more common in cases who drank alcohol at the time of enrollment vs. those who did not. cg11016563 resides in TRPC6 which has been previously shown to be overexpressed in EOC. These findings suggest two CpGs may serve as novel biomarkers for EOC susceptibility.

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.

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.

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.

Epidemiology of epithelial ovarian cancer

Globally, ovarian cancer is the seventh most common cancer in women and the eighth most common cause of cancer death, with five-year survival rates below 45%. Although age-standardised rates are stable or falling in most high-income countries, they are rising in many low and middle income countries. Furthermore, with increasing life-expectancy, the number of cases diagnosed each year is increasing. To control ovarian cancer we need to understand the causes. This will allow better prediction of those at greatest risk for whom screening might be appropriate, while identification of potentially modifable causes provides an opportunity for intervention to reduce rates. In this paper we will summarise the current state of knowledge regarding the known and possible causes of epithelial ovarian cancer and discuss some of the main theories of ovarian carcinogenesis. We will also briefly review the relationship between lifestyle and survival after a diagnosis of ovarian cancer.

Adult lifetime alcohol consumption and invasive epithelial ovarian cancer risk in a population-based case-control study

OBJECTIVE

Meta-analyses report a null association between recent alcohol consumption and ovarian cancer risk. However, because few studies investigated different types of alcohol over adult ages, we investigated adult lifetime and type (beer, wine, spirits) of consumption and risk.

METHODS

Consumption after age 20years was ascertained in 1144 invasive epithelial ovarian cancer cases and 2513 controls in a population-based case-control study (Alberta and British Columbia, Canada, 2001-2012). Non-drinkers consumed any types of alcohol <12 times per year on average. Logistic regression was use to estimate adjusted odds ratios [aOR] and 95% confidence intervals [CIs].

RESULTS

Wine consumption was associated with a risk reduction (aOR=0.67, 95% CI: 0.50-0.88) relative to non-drinkers, but not beer (aOR=1.06, 95% CI: 0.71-1.58) or spirits (aOR=0.98, 95% CI: 0.69-1.39). The reduced risk was stronger for exclusive red wine drinkers (aOR=0.44, 95% CI: 0.19-0.92) than white wine drinkers (aOR=0.79, 95% CI: 0.46-1.34), although most women drank both types of wine. Risk decreased with increasing cumulative consumption of any wine (P-trend<0.05) and was evident for the serous histotype. Wine consumption initiated prior to age 50 was associated with a risk reduction (e.g., at 40-49years, aOR=0.58, 95% CI: 0.42-0.78), but not drinking initiated after 50years of age. For any type, level, or age at initiation of alcohol consumption, we found no increased risks.

CONCLUSIONS

For the moderate consumption in this study, higher levels of wine consumption were generally associated with risk reductions; reductions may be stronger for red wine. Our results suggest that alcohol consumption that is guideline concordant will not increase epithelial ovarian cancer risk.

An epidemiologic risk prediction model for ovarian cancer in Europe: the EPIC study

BACKGROUND

Ovarian cancer has a high case-fatality ratio, largely due to late diagnosis. Epidemiologic risk prediction models could help identify women at increased risk who may benefit from targeted prevention measures, such as screening or chemopreventive agents.

METHODS

We built an ovarian cancer risk prediction model with epidemiologic risk factors from 202,206 women in the European Prospective Investigation into Cancer and Nutrition study.

RESULTS

Older age at menopause, longer duration of hormone replacement therapy, and higher body mass index were included as increasing ovarian cancer risk, whereas unilateral ovariectomy, longer duration of oral contraceptive use, and higher number of full-term pregnancies were decreasing risk. The discriminatory power (overall concordance index) of this model, as examined with five-fold cross-validation, was 0.64 (95% confidence interval (CI): 0.57, 0.70). The ratio of the expected to observed number of ovarian cancer cases occurring in the first 5 years of follow-up was 0.90 (293 out of 324, 95% CI: 0.81-1.01), in general there was no evidence for miscalibration.

CONCLUSION

Our ovarian cancer risk model containing only epidemiological data showed modest discriminatory power for a Western European population. Future studies should consider adding informative biomarkers to possibly improve the predictive ability of the model.

Association between alcohol consumption and the risk of ovarian cancer: a meta-analysis of prospective observational studies

Background

Alcohol consumption has been inconsistently associated with the risk of ovarian cancer. The purpose of this study was to summarize the data from prospective cohort studies on the relationship between alcohol consumption and ovarian cancer using a meta-analytic approach.

Methods

We performed electronic searches of PubMed, Embase, and the Cochrane Library in May 2014 to identify studies that examined the effects of alcohol consumption on the incidence of ovarian cancer. Only prospective cohort studies that reported effect estimates about the incidence of ovarian cancer with 95% confidence intervals (CIs) of alcohol intake were included.

Results

Collectively, we included 13 prospective studies that reported on data from 1,996,841 individuals and included 5,857 cases of ovarian cancer. Alcohol consumption had little to no effect on ovarian cancer incidence when compared to non-drinkers (risk ratio [RR], 1.03; 95% CI, 0.96–1.10; P = 0.473). Similarly, low (RR, 0.96; 95% CI, 0.93–1.00; P = 0.059), moderate (RR, 1.08; 95% CI, 0.92–1.27; P = 0.333), and heavy (RR, 0.99; 95% CI, 0.88–1.12; P = 0.904) alcohol consumption was not associated with the risk of ovarian cancer. Furthermore, subgroup analyses suggested that low alcohol intake was associated with a reduced risk of ovarian cancer whereas heavy alcohol intake was associated with an increased risk of ovarian cancer in multiple subpopulations.

Conclusions

Our study suggests that alcohol intake is not associated with an increased risk of ovarian cancer. Subgroup analyses indicated that alcohol consumption might be associated with the risk of ovarian cancer in specific population or in studies with specific characteristics.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-1355-8) contains supplementary material, which is available to authorized users.

A prospective cohort study of dietary indices and incidence of epithelial ovarian cancer

BACKGROUND

Several dietary indices have been developed to measure overall diet quality, including the Healthy Eating Index-2005 (HEI-2005), which measures adherence to the 2005 Dietary Guidelines from the USDA; the Alternative Healthy Eating Index-2010 (AHEI-2010), which is based on foods and nutrients predictive of chronic disease risk; and the Alternate Mediterranean Diet Score (aMDS), which is an index that characterizes traditional food patterns of Mediterranean countries. Few studies have evaluated diet quality and ovarian cancer risk.

METHODS

We assessed the associations of the HEI-2005, AHEI-2010, and aMDS with risk of epithelial ovarian cancer prospectively among women in the Nurses' Health Study. We used Cox proportional hazards models, adjusting for known ovarian cancer risk factors.

RESULTS

During 24 years of follow-up, we documented 696 incident epithelial ovarian cancer cases among 82,948 women with diet information. The multivariate adjusted hazard ratios (95% confidence interval; Ptrend) of epithelial ovarian cancer comparing the highest with the lowest quintile were 1.03 (0.80-1.34; 0.77) for the AHEI-2010, 0.85 (0.65-1.12; 0.57) for the HEI-2005, and 0.91 (0.71-1.18; 0.44) for the aMDS.

CONCLUSIONS

We did not observe any clear association of three diet quality scores with ovarian cancer risk. Further work should other metrics of evaluating diet quality that may be more relevant cancer risk.

The impact of moderate wine consumption on health

Wine is a traditional beverage that has been associated with both healthy and harmful effects. Conceptions like the so-called "French paradox" or the beneficial impact of the Mediterranean diet suggest benefit. Wine has a complex composition, which is affected by whether it is red or white or by other variables, like the variety of grapes or others. Alcohol and phenolic compounds have been attributed a participation in the benefits ascribed to wine. The case of alcohol has been extensively studied, but the key question is whether wine offers additional benefits. Resveratrol, a non-flavonoid compound, and quercetin, a flavonol, have received particular attention. There is much experimental work confirming a beneficial balance for both substances, particularly resveratrol, in various organs and systems. The pharmacological dosages used in many of those experiments have shed doubt, however, on the clinical translation of those findings. Clinical studies are limited by their observational nature as well as for the difficulties to abstract the benefits of wine from other confounders. Notwithstanding the doubts, there is reasonable unanimity in beneficial effects of moderate wine consumption in cardiovascular disease, diabetes, osteoporosis, maybe neurological diseases, and longevity. Observations are less enthusiastic in what refers to cancer. While considering these limitations, clinicians may spread the message that the balance of moderate wine consumption seems beneficial.

Alcohol-attributable cancer deaths and years of potential life lost in the United States

OBJECTIVES

Our goal was to provide current estimates of alcohol-attributable cancer mortality and years of potential life lost (YPLL) in the United States.

METHODS

We used 2 methods to calculate population-attributable fractions. We based relative risks on meta-analyses published since 2000, and adult alcohol consumption on data from the 2009 Alcohol Epidemiologic Data System, 2009 Behavioral Risk Factor Surveillance System, and 2009-2010 National Alcohol Survey.

RESULTS

Alcohol consumption resulted in an estimated 18,200 to 21,300 cancer deaths, or 3.2% to 3.7% of all US cancer deaths. The majority of alcohol-attributable female cancer deaths were from breast cancer (56% to 66%), whereas upper airway and esophageal cancer deaths were more common among men (53% to 71%). Alcohol-attributable cancers resulted in 17.0 to 19.1 YPLL for each death. Daily consumption of up to 20 grams of alcohol (≤ 1.5 drinks) accounted for 26% to 35% of alcohol-attributable cancer deaths.

CONCLUSIONS

Alcohol remains a major contributor to cancer mortality and YPLL. Higher consumption increases risk but there is no safe threshold for alcohol and cancer risk. Reducing alcohol consumption is an important and underemphasized cancer prevention strategy.

Recent alcohol consumption and risk of incident ovarian carcinoma: a pooled analysis of 5,342 cases and 10,358 controls from the Ovarian Cancer Association Consortium

BACKGROUND

Studies evaluating the association between alcohol intake and ovarian carcinoma (OC) are inconsistent. Because OC and ovarian borderline tumor histologic types differ genetically, molecularly and clinically, large numbers are needed to estimate risk associations.

METHODS

We pooled data from 12 case-control studies in the Ovarian Cancer Association Consortium comprising 5,342 OC cases, 1,455 borderline tumors and 10,358 controls with quantitative information on recent alcohol intake to estimate odds ratios (OR) and 95% confidence intervals (CI) according to frequencies of average daily intakes of beer, wine, liquor and total alcohol.

RESULTS

Total alcohol intake was not associated with all OC: consumption of >3 drinks per day compared to none, OR=0.92, 95% CI=0.76-1.10, P trend=0.27. Among beverage types, a statistically non-significant decreased risk was observed among women who consumed >8 oz/d of wine compared to none (OR=0.83, 95% CI=0.68-1.01, P trend=0.08). This association was more apparent among women with clear cell OC (OR, 0.43; 95% CI, 0.22-0.83; P trend=0.02), although based on only 10 cases and not statistically different from the other histologic types (P value for statistical heterogeneity between histologic types = 0.09). Statistical heterogeneity of the alcohol- and wine-OC associations was seen among three European studies, but not among eight North American studies. No statistically significant associations were observed in separate analyses evaluating risk with borderline tumors of serous or mucinous histology. Smoking status did not significantly modify any of the associations.

CONCLUSIONS

We found no evidence that recent moderate alcohol drinking is associated with increased risk for overall OC, or that variation in risk is associated strongly with specific histologic types. Understanding modifiable causes of these elusive and deadly cancers remains a priority for the research community.

Alcohol drinking and epithelial ovarian cancer risk. a systematic review and meta-analysis

OBJECTIVE

In order to provide an updated quantification of the association between alcohol drinking and epithelial ovarian cancer risk, we conducted a meta-analysis of published observational studies.

METHODS

Using PubMed, we performed a literature search of all case-control and cohort studies published as original articles in English up to September 2011. We included 27 observational studies, of which 23 were case-control studies, 3 cohort studies and one pooled analysis of prospective cohort studies, including a total of 16,554 epithelial ovarian cancer cases. We derived pooled meta-analytic estimates using random-effects models.

RESULTS

The pooled relative risk (RR) for any alcohol drinking compared with non/occasional drinking was 1.00 [95% confidence interval (CI), 0.95-1.05]. The RRs were 0.97 (95% CI, 0.92-1.02), 1.03 (95% CI, 0.96-1.11) and 1.09 (95% CI, 0.80-1.50) for light (≤ 1 drink/day), moderate (>1 to <3 drinks) and heavy drinking (≥ 3 drinks/day), respectively. In particular, the pooled RR for invasive epithelial ovarian cancers was 1.00 (95% CI, 0.95-1.06), while for borderline cancers was 0.96 (95% CI, 0.74-1.26). Stratified analyses across cancer histotypes revealed a modest protective effect of alcohol on endometrioid epithelial ovarian tumors (RR=0.82, 95% CI, 0.70-0.96), while no association was found for serous (RR=1.00, 95% CI, 0.84-1.19), mucinous (RR=0.91, 95% CI, 0.78-1.08) and clear cell (RR=0.93, 95% CI, 0.76-1.14) cancers. There was no evidence of publication bias.

CONCLUSIONS

This comprehensive meta-analysis provided no evidence of a material association between alcohol drinking and epithelial ovarian cancer risk.

Ovarian cancer risk factors by histologic subtypes in the NIH-AARP Diet and Health Study

Data suggest that risk factors for ovarian carcinoma vary by histologic type, but findings are inconsistent. We prospectively evaluated risk factors by histological subtypes of incident ovarian cancer (n = 849) in a cohort of 169,391 women in the NIH-AARP Diet and Health Study. We constructed Cox models of individual exposures by comparing case subtypes to the entire non-case group and assessed p-heterogeneity in case-case comparisons using serous as the reference category. Substantial risk differences between histologic subtypes were observed for menopausal hormone therapy (MHT) use, oral contraceptive (OC) use, parity and body mass index (p-heterogeneity = 0.01, 0.03, 0.05, 0.03, respectively). MHT users were at increased risk for all histologic subtypes except for mucinous carcinomas, where risk was reduced (relative risk (RR) = 0.37; 95% confidence interval (CI): 0.18, 0.80). OC users were only at significantly decreased risk for serous cancers (RR = 0.69; 95% CI: 0.55, 0.85). Although parity was inversely associated with risk of all subtypes, the RRs ranged from 0.28 (clear cell) to 0.83 (serous). Obesity was a significant risk factor only for endometrioid cancers (RR = 1.64; 95% CI: 1.00, 2.70). Our findings support a link between etiological factors and histological heterogeneity in ovarian carcinoma.

Folate, vitamin B(6) , vitamin B(12) , methionine and alcohol intake in relation to ovarian cancer risk

Folate, methionine, vitamin B(6) and vitamin B(12) may influence carcinogenesis due to their roles in the one-carbon metabolism pathway, which is critical for DNA synthesis, methylation and repair. Low intake of these nutrients has been associated with an increased risk of breast, colon and endometrial cancers. Previous studies that have examined the relation between these nutrients and ovarian cancer risk have been inconsistent and have had limited power to examine the relation by histologic subtype. We investigated the association between folate, methionine, vitamin B(6) , vitamin B(12) and alcohol among 1910 women with ovarian cancer and 1989 controls from a case-control study conducted in eastern Massachusetts and New Hampshire from 1992 to 2008. Diet was assessed via food frequency questionnaire. Participants were asked to recall diet one-year before diagnosis or interview. Logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (95% CIs). We also examined whether the associations varied by ovarian cancer histologies using polytomous logistic regression. We observed an inverse association between dietary vitamin B(6) (covariate-adjusted OR = 0.76, 95% CI 0.64-0.92; p(trend) = 0.002) and methionine intake (covariate-adjusted OR = 0.72, 95% CI = 0.60-0.87; p(trend) < 0.001) and ovarian cancer risk comparing the highest to lowest quartile. The association with dietary vitamin B(6) was strongest for serous borderline (covariate-adjusted OR = 0.49, 95% CI = 0.32-0.77; p(trend) = 0.001) and serous invasive (covariate-adjusted OR = 0.74, 95% CI = 0.58-0.94; p(trend) = 0.012) subtypes. Overall, we observed no significant association between folate and ovarian cancer risk. One-carbon metabolism related nutrients, especially vitamin B(6) and methionine, may lower ovarian cancer risk.

Wine drinking and epithelial ovarian cancer risk: a meta-analysis

OBJECTIVE

Wine has been the focus in the prevention of epithelial ovarian cancer (EOC) development because resveratrol abundant in wine has anti-carcinogenic properties. However, epidemiologic results have been heterogenous in the chemopreventive effect of wine on the development of EOC. Thus, we performed a meta-analysis for comparing EOC risk between wine and never drinkers using previous related studies.

METHODS

After extensive search of the literature between January 1986 and December 2008, we analyzed 10 studies (3 cohort and 7 case control studies) with 135,871 women, who included 65,578 of wine and 70,293 of never drinkers.

RESULTS

In all studies, there was no significant difference in EOC risk between wine and never drinkers (odds ratio [OR], 1.13; 95% confidence interval [CI], 0.92 to 1.38; random effects). When we performed re-analysis according to the study design, 3 cohort and 7 case control studies showed that there were also no significant differences in EOC risk between wine and never drinkers, respectively (OR, 1.44 and 1.04; 95% CI, 0.74 and 2.82 and 0.88 to 1.22; random effects). In sub-analyses using 2 case-control studies, EOC risk was not different between former and never drinkers (OR, 1.12; 95% CI, 0.87 to 1.44; fixed effect), and between current and former drinkers (OR, 0.74; 95% CI, 0.41 to 1.34; random effects).

CONCLUSION

Although resveratrol, abundantly found in wine, is a promising naturally occurring compound with chemopreventive properties on EOC in preclinical studies, this meta-analysis suggests the epidemiologic evidence shows no association between wine drinking and EOC risk.

Chronic alcohol consumption prevents 8-hydroxyguanine accumulation in 3'-methyl-4-dimethylaminoazobenzene-treated mouse liver

Alcohol consumption is known to have opposing effects on carcinogenesis: promotion and prevention. In this study, we examined the effects of 12% ethanol on oxidative DNA damage accumulation and its repair in mouse livers treated with 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB), a well-known hepatic carcinogen. We previously reported that 3'-MeDAB increased 8-hydroxyguanine (8-OH-Gua) accumulation and its repair activity, accompanied by the fragmentation of 8-oxoguanine DNA glycosylase 1 (OGG1), the main repair enzyme of 8-OH-Gua. The present results showed that 12% ethanol intake attenuated the 8-OH-Gua accumulation, but not the fragmentation of OGG1 induced by 3'-MeDAB. Additionally, no significant changes in oxidative status, as monitored by lipid peroxidation (LPO), were observed among the 3'-MeDAB-treated mouse livers with/without alcohol administration. These findings suggested that 12% ethanol consumption may reduce the risk of 3'-MeDAB-induced carcinogenesis by decreasing 8-OH-Gua accumulation.

Comparing measures of model selection for penalized splines in Cox models

This article presents an application and a simulation study of model fit criteria for selecting the optimal degree of smoothness for penalized splines in Cox models. The criteria considered were the Akaike information criterion, the corrected AIC, two formulations of the Bayesian information criterion, and a generalized cross-validation method. The estimated curves selected by the five methods were compared to each other in a study of rectal cancer mortality in autoworkers. In the stimulation study, we estimated the fit of the penalized spline models in six exposure-response scenarios, using the five model fit criteria. The methods were compared based on a mean squared-error score and the power and size of hypothesis tests for any effect and for detecting nonlinearity. All comparisons were made across a range in the total sample size and number of cases.

Flavonoid intake and ovarian cancer risk in a population-based case-control study

Several recent studies have evaluated the association between dietary flavonoid intake and ovarian cancer risk, and all reported significant or suggestive inverse associations with certain flavonoids or flavonoid subclasses; however, most of these studies were small to moderate in size. We, therefore, examined this association in a large, population-based case-control study. We calculated intake of 5 common dietary flavonoids (myricetin, kaempferol, quercetin, luteolin, and apigenin), as well as total intake of these flavonoids, for 1,141 cases and 1,183 frequency-matched controls. We used unconditional logistic regression to estimate the relative risk (RR) of ovarian cancer for each quintile of flavonoid intake when compared with the lowest quintile. We did not observe an association between total flavonoid intake and ovarian cancer risk. The multivariable-adjusted RR for the highest versus lowest quintile of total flavonoid intake was 1.06 (95% confidence interval [CI] = 0.78-1.45). In analyses of each individual flavonoid, only intake of apigenin was associated with a borderline significant decrease in risk (RR, highest vs. lowest quintile = 0.79, 95% CI = 0.59-1.06; p-trend = 0.26), and this association was significant after adjustment for intake of the other 4 individual flavonoids (comparable RR = 0.72, 95% CI = 0.53-0.98; p-trend = 0.09). These results provide limited support for an association between flavonoid intake and ovarian cancer risk. However, given the findings of previous studies and the biologic plausibility of this association, additional studies are warranted.

Dietary patterns and ovarian cancer risk

BACKGROUND

Evidence for a role of individual foods and nutrients in the causation of ovarian cancer is inconclusive. To date, few studies have considered dietary patterns in relation to ovarian cancer risk.

OBJECTIVE

We conducted a population-based case-control study in Australia to identify and analyze dietary patterns in relation to ovarian cancer risk.

DESIGN

Principal components analysis of 40 food groups was performed to identify eating patterns in 683 women with epithelial ovarian cancer and in 777 control women aged 18-79 y. Detailed information on risk factors was obtained through face-to-face interviews, whereas dietary information was obtained by administering a semiquantitative food-frequency questionnaire for subjects to complete themselves. Multivariable-adjusted odds ratios (ORs) for ovarian cancer risk were estimated with logistic regression modeling.

RESULTS

Three major eating patterns were identified: "snacks and alcohol," "fruit and vegetable," and "meat and fat." A significant inverse association between the snacks and alcohol pattern and ovarian cancer risk (highest compared with lowest group, multivariable-adjusted OR: 0.59; 95% CI: 0.43, 0.82; P for trend: 0.001) was attenuated after further adjustment for white or red wine intake. The fruit and vegetable pattern was not associated with risk. The meat and fat pattern was associated with an increased risk of ovarian cancer (highest compared with lowest group, multivariable-adjusted OR: 2.49; 95% CI: 1.75, 3.55; P for trend < 0.0001). Further adjustment for body mass index strengthened this association.

CONCLUSIONS

A diet characterized by high meat and fat intake may increase the risk of epithelial ovarian cancer. A diet high in fruit and vegetables was not associated with reduced risk.

Epidemiology of ovarian cancer

Ovarian cancer represents the sixth most commonly diagnosed cancer among women in the world, and causes more deaths per year than any other cancer of the female reproductive system. Despite the high incidence and mortality rates, the etiology of this disease is poorly understood. Established risk factors for ovarian cancer include age and having a family history of the disease, while protective factors include increasing parity, oral contraceptive use, and oophorectomy. Lactation, incomplete pregnancies, and surgeries such as hysterectomy and tubal ligation may confer a weak protective effect against ovarian cancer. Infertility may contribute to ovarian cancer risk among nulliparous women. Other possible risk factors for ovarian cancer include postmenopausal hormone-replacement therapy and lifestyle factors such as cigarette smoking and alcohol consumption. Many of the causes of ovarian cancer are yet to be identified. Additional research is needed to better understand the etiology of this deadly disease.

Caffeine, alcohol, smoking, and the risk of incident epithelial ovarian cancer

BACKGROUND

Smoking, caffeine, and alcohol intake are all potentially modifiable factors that have an unclear association with ovarian cancer risk. Therefore, the associations between these exposures and ovarian cancer risk were prospectively examined among 110,454 women in the Nurses' Health Study (NHS) for the smoking analyses and 80,253 women for the dietary analyses.

METHODS

Women completed biennial questionnaires assessing ovarian cancer risk factors beginning in 1976, with food frequency questionnaires administered every 2 to 4 years starting in 1980. For the smoking analyses, 737 confirmed cases of epithelial ovarian cancer were identified and for the dietary aims, 507 cases were identified through June 1, 2004.

RESULTS

Compared with never-smokers, neither current nor past smoking was associated with ovarian cancer risk overall; however, both were associated with mucinous tumors (n = 69; rate ratio [RR], past = 2.02 [95% confidence interval (CI), 1.15-3.55]; RR, current = 2.22 [95% CI, 1.16-4.24]). A modest inverse association between caffeine intake and ovarian cancer risk was observed (RR, top vs bottom quintile = 0.80; 95% CI, 0.60-1.07 [P = .03]), which was strongest for women who had never used either oral contraceptives (RR = 0.65; 95% CI, 0.46-0.92 [P for heterogeneity = .02]) or postmenopausal hormones (RR = 0.57; 95% CI, 0.36-0.91 [P for heterogeneity = .13]). Alcohol was not associated with ovarian cancer risk.

CONCLUSIONS

The results of the current study suggest that cigarette smoking may only increase the risk for mucinous ovarian tumors, and alcohol intake was not associated with risk. However, an inverse association was observed between caffeine intake and ovarian cancer risk, particularly in women not using hormones; this finding merits further study.

A prospective study of dietary flavonoid intake and incidence of epithelial ovarian cancer

Flavonoids are antioxidant compounds found in plants, including fruits, vegetables and tea. No prior prospective studies have examined the association between intake of flavonoids in the flavonol and flavone subclasses and ovarian cancer risk. We analyzed the association between intake of 5 common dietary flavonoids and incidence of epithelial ovarian cancer among 66,940 women in the Nurses' Health Study. We calculated each participant's intake of myricetin, kaempferol, quercetin, luteolin and apigenin from dietary data collected at multiple time points, and used Cox proportional hazards regression to model the incidence rate ratio (RR) of ovarian cancer for each quintile of intake. Our analysis included 347 cases diagnosed between 1984 and 2002, and 950,347 person-years of follow-up. There was no clear association between total intake of the 5 flavonoids examined and incidence of ovarian cancer (RR = 0.75 for the highest versus lowest quintile, 95% confidence interval [CI] = 0.51-1.09). However, there was a significant 40% decrease in ovarian cancer incidence for the highest versus lowest quintile of kaempferol intake (RR = 0.60, 95% CI = 0.42-0.87; p-trend = 0.002), and a significant 34% decrease in incidence for the highest versus lowest quintile of luteolin intake (RR = 0.66, 95% CI = 0.49-0.91; p-trend = 0.01). There was evidence of an inverse association with consumption of tea (nonherbal) and broccoli, the primary contributors to kaempferol intake in our population. These data suggest that dietary intake of certain flavonoids may reduce ovarian cancer risk, although additional prospective studies are needed to further evaluate this association. If confirmed, these results would provide an important target for ovarian cancer prevention.

Wine and other alcohol consumption and risk of ovarian cancer in the California Teachers Study cohort

Objective

Whether alcohol consumption influences ovarian cancer risk is unclear. Therefore, we investigated the association between alcohol intake at various ages and risk of ovarian cancer.

Methods

Among 90,371 eligible members of the California Teachers Study cohort who completed a baseline alcohol assessment in 1995–1996, 253 women were diagnosed with epithelial ovarian cancer by the end of 2003. Multivariate Cox proportional hazards regression analysis was performed to estimate relative risks (RRs) and 95% confidence intervals (CIs).

Results

Consumption of total alcohol, beer, or liquor in the year prior to baseline, at ages 30–35 years, or at ages 18–22 years was not associated with risk of ovarian cancer. Consumption of at least one glass per day of wine, compared to no wine, in the year before baseline was associated with increased risk of developing ovarian cancer: RR = 1.57 (95% CI 1.11–2.22), P_trend = 0.01. The association with wine intake at baseline was particularly strong among peri-/post-menopausal women who used estrogen-only hormone therapy and women of high socioeconomic status.

Conclusions

Alcohol intake does not appear to affect ovarian cancer risk. Constituents of wine other than alcohol or, more likely, unmeasured determinants of wine drinking were associated with increased risk of ovarian cancer.