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

Association between coffee and tea consumption and ovarian cancer incidence: A prospective analysis in the PLCO dataset

Epidemiological evidence regarding the relationship between coffee and tea consumption and the risk of ovarian cancer (OC) is inconsistent. Therefore, we aimed to quantitatively investigate this topic in a large prospective cohort study. This cohort study included 24,715 individuals recruited from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trials between 1993 and 2001. The data used for our analysis included the latest follow-up information collected up to 2015. Coffee intake of ≥4 cups/day (hazard ratio [HR], 0.586; 95% confidence interval [CI]: 0.356-0.966) or caffeine intake of 458.787 mg/day (HR, 0.607; 95% CI: 0.411-0.895) were associated with the lowest HR of incident OC in the fully adjusted model. Participants who consumed varying amounts of tea did not exhibit a statistically significant reduction in the risk of OC. Our findings suggest that a higher consumption of coffee or caffeine is associated with a reduced risk of OC. However, no statistically significant association was observed between tea consumption and the risk of OC.

Prevention of Epithelial Ovarian Cancer

Given the challenges with achieving effective and durable treatment for epithelial ovarian cancer, primary prevention is highly desirable. Fortunately, decades of research have provided evidence for several strategies that can be deployed to optimize risk reduction. These include surgery, chemoprevention, and lifestyle factor modifications. These broad categories vary in terms of the magnitude of risk reduction possible, the possible short-term and long-term side effects, the degree of difficulty, and acceptability. Thus, the concept of a risk-based model to personalize preventive interventions is advocated to guide discussion between care providers and women at risk. For women with inherited major gene mutations that greatly increase risk of ovarian cancer, surgical approaches have favorable risk to benefit ratios. Chemoprevention and lifestyle factor modifications portend a lower degree of risk reduction but confer lower risk of undesirable side effects. Since complete prevention is not currently possible, better methods for early detection remain a high priority.

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.

Epidemiological trends and risk factors of gynecological cancers: an update

Gynecological cancers, the most common cancer among women worldwide, disrupt the function of women's reproductive system, significantly impacting the quality of life. The epidemiological patterns of gynecological cancers differ in various regions and alter over time. The main challenge to deal with women's cancers is focusing on potential plans to improve patient outcomes. The epidemiology and general risk elements of gynecological cancers are important in the management of these cancers, so all of the reported risk factors in gynecological cancers have been evaluated in the present review. Due to the role of gynecological cancers in women's health, preventive measures and modifiable lifestyles together with early detection in high-risk groups are effective strategies that can reduce mortality rates. This review summarizes the epidemiology and global risk factors of gynecological cancers alongside others to better management of these malignancies and improve the quality of life in the affected patients.

Association between Different Types of Tea Consumption and Risk of Gynecologic Cancer: A Meta-Analysis of Cohort Studies

Plenty of studies have shown that tea has an effect of inhibiting gynecologic tumors. However, there still remained controversy of the association between tea and gynecologic tumors in epidemiological studies. In this study, PubMed, Embase, and Cochrane Database were used to search the literature from 1 January 1960 to 26 December 2022 to investigate the association between tea intake and gynecologic cancer risk. In total, 19 cohort studies with 2,020,980 subjects and 12,155 gynecological tumor cases were retrieved. The pooled relative risk (RR) of gynecologic tumor for tea intake was 1.00 (95% CI: 0.96-1.04). RRs were 0.94 (95% CI: 0.88-1.01) for ovarian cancer, 1.02 (95% CI: 0.97-1.07) for endometrial cancer, and 1.06 (95% CI: 0.91-1.23) for cervical cancer. Subgroup analyses were adopted based on the tea type and geographic location. Interestingly, significant preventive impact of non-herbal tea on ovarian cancer (pooled relative risk: 0.67; 95% CI: 0.55-0.81) was found, especially for black tea (pooled relative risk: 0.64; 95% CI: 0.51-0.80). Dose-response analysis indicated that although it is not statistically significant, a decreasing trend of ovarian cancer risk could be observed when the tea consumption was 1.40 to 3.12 cups/day. In conclusion, our findings suggested that ovarian cancer, but not other gynecologic cancers, could possibly be prevented by drinking non-herbal tea. In addition, the preventive impact of green tea on gynecologic cancer seemed to be relatively weak and needs further cohorts to validate it.

Tobacco Smoking and Survival Following a Diagnosis with Ovarian Cancer

BACKGROUND

Little is known about the influence of smoking on ovarian cancer survival. We investigated this relationship in a hospital-based study.

METHODS

Analyses included 519 women with ovarian cancer. We used multivariable adjusted Cox proportional hazards regression models to estimate HRs and 95% confidence intervals (CI).

RESULTS

Risk of all-cause mortality was increased for current smokers (HR = 1.70; 95% CI: 1.09-2.63) versus never smokers, especially for those with ≥15 cigarettes per day (HR = 1.92; 95% CI: 1.15-3.20). Results were largely similar after additional adjustment for debulking status (current vs. never smokers, HR = 2.96; 95% CI: 1.07-8.21) or neoadjuvant chemotherapy (comparable HR = 2.87; 95% CI: 1.02-8.06). Compared with never smokers, smoking duration ≥20 years (HR = 1.38; 95% CI: 0.94-2.03) and ≥20 pack-years (HR = 1.35; 95% CI: 0.92-1.99) were suggestively associated with worse outcomes. Current smoking was also positively associated with the risk of mortality among patients with ovarian cancer recurrence (current vs. never/past smokers, HR = 2.79; 95% CI: 1.44-5.41), despite the null association between smoking and recurrence (HR = 1.46; 95% CI: 0.86-2.48). Furthermore, no association was observed for smoking initiation before age 18 (HR = 1.22; 95% CI: 0.80-1.85), or either environmental smoke exposure at home (HR = 1.16; 95% CI: 0.76-1.78) or at work (HR = 1.10; 95% CI: 0.75-1.60).

CONCLUSIONS

Our results suggest active tobacco smoking is associated with worse ovarian cancer outcomes, particularly after a recurrence.

IMPACT

Our findings support structured smoking cessation programs for patients with ovarian cancer, especially in recurrent settings. Further research to confirm these findings and examine the interplay between smoking and the tumor immune microenvironment may help provide insight into ovarian cancer etiology.

Lifetime caffeine intake and the risk of epithelial ovarian cancer

BACKGROUND

Caffeine intake has been inconsistently associated with the risk of ovarian cancer in previous studies. The measure of caffeine in these studies has not always distinguished between caffeinated and decaffeinated sources, and the time for which intake was assessed was often for late adulthood and thus may have excluded the etiologic window. We investigated lifetime caffeine intake from caffeinated coffee, black tea, green tea and cola sodas in relation to ovarian cancer risk.

METHODS

Among 497 cases and 904 controls in a population-based case-control study in Montreal, Canada, lifetime intake of caffeinated coffee, black tea, green tea and cola sodas was assessed and used to calculate lifetime total intake of caffeine. Unconditional multivariable logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the association between caffeine intake and ovarian cancer risk overall, as well as by menopausal status. Multivariable polytomous logistic regression was used to estimate the associations for invasive and borderline ovarian cancers separately.

RESULTS

Almost all participants (98.4% of cases and 97.5% of controls) had consumed caffeine in their lifetime. The mean (standard deviation) daily consumption of caffeine over the lifetime was of 117 (89) mg/day among cases and 120 (118) mg/day among controls. The OR (95% CI) of ovarian cancer for the highest versus lowest quartile of lifetime caffeine intake was 1.17 (0.83-1.64). According to menopausal status, the OR (95% CI) was 1.56 (0.85-2.86) for premenopausal women and 0.94 (0.66-1.34) for postmenopausal women, comparing the highest to lowest tertiles of intake. Associations for invasive and borderline ovarian cancers separately were similar to that observed for ovarian cancer overall.

CONCLUSION

Lifetime caffeine intake was not strongly associated with ovarian cancer risk. A difference in relationship by menopausal status is possible.

Review of Mendelian Randomization Studies on Ovarian Cancer

Ovarian cancer (OC) is one of the deadliest gynecological cancers worldwide. Previous observational epidemiological studies have revealed associations between modifiable environmental risk factors and OC risk. However, these studies are prone to confounding, measurement error, and reverse causation, undermining robust causal inference. Mendelian randomization (MR) analysis has been established as a reliable method to investigate the causal relationship between risk factors and diseases using genetic variants to proxy modifiable exposures. Over recent years, MR analysis in OC research has received extensive attention, providing valuable insights into the etiology of OC as well as holding promise for identifying potential therapeutic interventions. This review provides a comprehensive overview of the key principles and assumptions of MR analysis. Published MR studies focusing on the causality between different risk factors and OC risk are summarized, along with comprehensive analysis of the method and its future applications. The results of MR studies on OC showed that higher BMI and height, earlier age at menarche, endometriosis, schizophrenia, and higher circulating β-carotene and circulating zinc levels are associated with an increased risk of OC. In contrast, polycystic ovary syndrome; vitiligo; higher circulating vitamin D, magnesium, and testosterone levels; and HMG-CoA reductase inhibition are associated with a reduced risk of OC. MR analysis presents a2 valuable approach to understanding the causality between different risk factors and OC after full consideration of its inherent assumptions and limitations.

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.

Caffeine and Cisplatin Effectively Targets the Metabolism of a Triple-Negative Breast Cancer Cell Line Assessed via Phasor-FLIM

Triple-negative tumor cells, a malignant subtype of breast cancer, lack a biologically targeted therapy. Given its DNA repair inhibiting properties, caffeine has been shown to enhance the effectiveness of specific tumor chemotherapies. In this work, we have investigated the effects of caffeine, cisplatin, and a combination of the two as potential treatments in energy metabolism for three cell lines, triple-negative breast cancer (MDA-MB-231), estrogen-receptor lacking breast cancer (MCF7) and breast epithelial cells (MCF10A) using a sensitive label-free approach, phasor-fluorescence lifetime imaging microscopy (phasor-FLIM). We found that solely using caffeine to treat MDA-MB-231 shifts their metabolism towards respiratory-chain phosphorylation with a lower ratio of free to bound NADH, and a similar trend is seen in MCF7. However, MDA-MB-231 cells shifted to a higher ratio of free to bound NADH when cisplatin was added. The combination of cisplatin and caffeine together reduced the survival rate for MDA-MD231 and shifted their energy metabolism to a higher fraction of bound NADH indicative of oxidative phosphorylation. The FLIM and viability results of MCF10A cells demonstrate that the treatments targeted cancer cells over the normal breast tissue. The identification of energy metabolism alteration could open up strategies of improving chemotherapy for malignant breast cancer.

Prediagnosis and postdiagnosis smoking and survival following diagnosis with ovarian cancer

Little is known about the influence of prediagnosis and postdiagnosis smoking and smoking cessation on ovarian cancer survival. We investigated this relationship in two prospective cohort studies, the Nurses' Health Study (NHS) and NHSII. Analyses included 1,279 women with confirmed invasive, Stage I-III epithelial ovarian cancer. We used Cox proportional hazards regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for ovarian cancer-specific mortality by smoking status, adjusting for age and year of diagnosis, tumor stage, histologic subtype, body mass index and nonsteroidal anti-inflammatory use (postdiagnosis models only). When examining prediagnosis smoking status (assessed a median of 12 months before diagnosis), risk of death was significantly increased for former smokers (HR = 1.19, 95% CI: 1.02-1.39), and suggestively for current smokers (HR = 1.21, 95% CI: 0.96-1.51) vs. never smokers. Longer smoking duration (≥20 years vs. never, HR = 1.23, 95% CI: 1.05-1.45) and higher pack-years (≥20 pack-years vs. never, HR = 1.28, 95% CI: 1.07-1.52) were also associated with worse outcome. With respect to postdiagnosis exposure, women who smoked ≥15 cigarettes per day after diagnosis (assessed a median of 11 months after diagnosis) had increased mortality compared to never smokers (HR = 2.34, 95% CI: 1.63-3.37). Those who continued smoking after diagnosis had 40% higher mortality (HR = 1.40, 95% CI: 1.05-1.87) compared to never smokers. Overall, our results suggest both prediagnosis and postdiagnosis smoking are associated with worse ovarian cancer outcomes.

Caffeine, Type of Coffee, and Risk of Ovarian Cancer: A Dose-Response Meta-Analysis of Prospective Studies

CONTEXT

Prospective studies on caffeine and different types of coffee intake in relation to the risk of ovarian cancer have shown conflicting results.

OBJECTIVE

The aim of the present study was to perform a dose-response meta-analysis of cohort studies on the association between dietary caffeine intake, different types of coffee consumption, and the risk of ovarian cancer.

DATA SOURCES

PubMed/Medline, ISI Web of Science, Scopus, and EMBASE were searched to identify relevant studies reported until October 2018.

STUDY SELECTION

Prospective cohort studies that had considered caffeine or different types of coffee as the exposure variable and ovarian cancer as the main outcome variable or as one of the outcome variables were included in our systematic review and meta-analysis. Two of us independently screened 9344 publications. A total of 14 cohort studies were included in the meta-analysis.

DATA EXTRACTION

Two of us independently extracted the data. Any disagreements were resolved in consultation with the principal investigator.

RESULTS

Combining 13 effect sizes, we found no substantial association between coffee consumption and risk of ovarian cancer [risk ratio (RR), 1.08; 95% CI, 0.89 to 1.33]. Also, one additional cup daily of coffee consumption was marginally associated with an increased risk of ovarian cancer (RR, 1.02; 95% CI, 0.99 to 1.05; P = 0.21; I2 = 0.0%; Pheterogeneity = 0.68). No statistically significant association was observed between caffeine intake or caffeinated or decaffeinated coffee consumption and the risk of ovarian cancer.

CONCLUSIONS

We found no statistically significant association between caffeine intake or different types of coffee and the risk of ovarian cancer.

Association between Cigarette Smoking and Histotype-Specific Epithelial Ovarian Cancer: A Review of Epidemiologic Studies

Many studies have demonstrated that smoking can influence ovarian cancer risk and survival; however, the number of studies investigating this relationship according to histologic subtypes is limited. We conducted a review of epidemiologic research that assessed the role of smoking on ovarian cancer risk and survival after diagnosis, specifically capturing studies that discerned between various histologic subtypes of this disease. In the majority of studies, current smoking was associated with increased risk of mucinous cancer. There was also evidence of a decreased risk of clear cell and endometrioid histotypes. No significant association was observed between cigarette smoking and serous cancer. In the studies investigating the relationship between smoking and survival, all the studies reported an increased risk of mortality associated with smoking. Smoking appeared to be a risk factor for both ovarian cancer risk and mortality. Future studies need to investigate further a potential link between smoking and ovarian cancer by having a better assessment of exposure to smoking and having a larger number of participants with the ability to detect associations within rare histotypes.

Dose-risk relationships between cigarette smoking and ovarian cancer histotypes: a comprehensive meta-analysis

PURPOSE

Although smoking has not been associated with overall ovarian cancer risk, a different impact on various histotypes has been reported. Our aim is to provide an accurate, up-to-date estimate of the dose-risk relationships between cigarette smoking and epithelial ovarian cancer, overall and by histotypes.

METHODS

Using an innovative approach for the identification of original study publications, we conducted a systematic review and meta-analysis of epidemiological studies published on the topic until September 2018. Summary relative risks (RR) for cigarette smoking were estimated using random-effects models; dose-risk relationships were evaluated using one-stage random-effects models with restricted cubic splines.

RESULTS

Thirty-seven studies were considered in the meta-analysis. The summary RRs for current versus never smokers were 1.05 (95% confidence interval CI 0.95-1.16) for overall ovarian cancer, 1.78 (95% CI 1.52-2.07) for mucinous, 0.77 (95% CI 0.65-0.93) for clear cell, 0.81 (95% CI 0.73-0.91) for endometrioid, and 1.05 (95% CI 0.94; 1.17) for serous cancer. The risk of borderline mucinous (RR 2.09) and serous (RR 1.16) tumors was higher than for invasive cancers (RR 1.44 and 0.95, respectively). For mucinous cancer, risk was noticeably higher with smoking intensity and duration (RR 2.35 for 20 cigarettes/day, and 2.11 for 20 years of smoking). A non-significant linear relation was found with smoking intensity, duration, and time since quitting for overall ovarian cancer and other histotypes.

CONCLUSIONS

This uniquely large and comprehensive meta-analysis confirms that although cigarette smoking does not appear to be a risk factor for ovarian cancer, and it is even slightly protective for some rare histotypes, there is a strong dose-risk relationship with mucinous ovarian cancer.

In Utero Exposure to Benzo[a]pyrene Induces Ovarian Mutations at Doses That Deplete Ovarian Follicles in Mice

Polycyclic aromatic hydrocarbons like benzo[a]pyrene (BaP) are ubiquitous environmental contaminants formed during incomplete combustion of organic materials. Our prior work showed that transplacental exposure to BaP depletes ovarian follicles and increases prevalence of epithelial ovarian tumors later in life. We used the MutaMouse transgenic rodent model to address the hypothesis that ovarian mutations play a role in tumorigenesis caused by prenatal exposure to BaP. Pregnant MutaMouse females were treated with 0, 10, 20, or 40 mg/(kg day) BaP orally on gestational days 7-16, covering critical windows of ovarian development. Female offspring were euthanized at 10 weeks of age; some ovaries with oviducts were processed for follicle counting; other ovaries/oviducts and bone marrow were processed for determination of lacZ mutant frequency (MF). Mutant plaques were pooled within dose groups and sequenced to determine the mutation spectrum. BaP exposure caused highly significant dose-related decreases in ovarian follicles and increases in ovarian/oviductal and bone marrow mutant frequencies at all doses. Absence of follicles, cell packets, and epithelial tubular structures were observed with 20 and 40 mg/(kg day) BaP. Depletion of ovarian germ cells was inversely associated with ovarian MF. BaP induced primarily G > T and G > C transversions and deletions in ovaries/oviducts and bone marrow cells and produced a mutation signature highly consistent with that of tobacco smoking in human cancers. Overall, our results show that prenatal BaP exposure significantly depletes ovarian germ cells, causes histopathological abnormalities, and increases the burden of ovarian/oviductal mutations, which may be involved in pathogenesis of epithelial ovarian tumors. Environ. Mol. Mutagen. 60:410-420, 2019. © 2018 Her Majesty the Queen in Right of Canada.

Ovarian cancer in the world: epidemiology and risk factors

Aim: Ovarian cancer is one of the most common gynecologic cancers that has the highest mortality rate. Considering the fact that knowledge on the incidence, mortality of ovarian cancer, as well as its risk factors is necessary for planning and preventing complications, this study was conducted with the aim of examining the epidemiology and risk factors of ovarian cancer in the world.

Materials and methods: In order to access the articles, Medline, Web of Science Core Collection, and Scopus databases were searched from their start to the year 2018. Full-text, English observational studies that referred to various aspects of ovarian cancer were included in the study.

Results: In total, 125 articles that had been published during the years 1925–2018 were entered into the study. Ovarian cancer is the seventh most common cancer among women. Increased risk factors of cancer have led to an upward trend in the incidence of cancer around the world. In 2018, 4.4% of entire cancer-related mortality among women was attributed to ovarian cancer. Although the incidence of cancer is higher among high Human Development Index (HDI) countries, the trend of mortality rate tends to be reversing. Various factors affect the occurrence of ovarian cancer, from which genetic factor are among the most important ones. Pregnancy, lactation, and oral contraceptive pills play a role in reducing the risk of this disease.

Conclusion: This study provides significant evidence about ovarian cancer. Considering the heavy burden of ovarian cancer on women's health, preventive measures as well as health education and early detection in high risk groups of women are highly recommended. Although some risk factors cannot be changed, a focus on preventable risk factors may reduce the risk of ovarian cancer. More studies are needed to explore the role of unclear risk factors in ovarian cancer occurrence.

Role of tumor microenvironment in ovarian cancer pathobiology

Ovarian cancer is the fifth most common cancer affecting the female population and at present, stands as the most lethal gynecologic malignancy. Poor prognosis and low five-year survival rate are attributed to nonspecific symptoms and below par diagnostic criteria at early phases along with a lack of effective treatment at advanced stages. It is thus of utmost importance to understand ovarian carcinoma through several lenses including its molecular pathogenesis, epidemiology, histological subtypes, hereditary factors, diagnostic approaches and methods of treatment. Above all, it is crucial to dissect the role that the unique peritoneal tumor microenvironment plays in ovarian cancer progression and metastasis. This review seeks to highlight several important aspects of ovarian cancer pathobiology as a means to provide the necessary background to approach ovarian malignancies in the future.

Tea consumption and the risk of ovarian cancer: A meta-analysis of epidemiological studies

A large number of epidemiological studies have provided conflicting results about the relationship between tea consumption and ovarian cancer. This study aimed to clarify the association between tea consumption and ovarian cancer. A literature search of the MEDICINE, Scopus, PubMed, and Web of Science databases was performed in April 2016. A total of 18 (11 case-control and 7 cohort) studies, representing data for 701,857 female subjects including 8,683 ovarian cancer cases, were included in the meta-analysis. A random-effects meta-analysis was used to compute the pooled relative risks (RR), meta regression, and publication bias, and heterogeneity analyses were performed for the included trials. We found that tea consumption had a significant protective effect against ovarian cancer (relative risk [RR] = 0.86; 95% confidence interval [CI]: 0.76, 0.96). The relationship was confirmed particularly after adjusting for family history of cancer (RR = 0.85; 95% CI: 0.72, 0.97), menopause status (RR = 0.85; 95% CI: 0.72, 0.98), education (RR = 0.82; 95% CI: 0.68, 0.96), BMI (RR = 0.85; 95% CI: 0.70, 1.00), smoking (RR = 0.83; 95% CI: 0.72, 0.93) and Jadad score of 3 (RR = 0.76; 95% CI: 0.56, 0.95) and 5 (RR = 0.74; 95% CI: 0.59, 0.89). The Begg's and Egger's tests (all P > 0.01) showed no evidence of publication bias. In conclusion, our meta-analysis showed an inverse association between tea consumption and ovarian cancer risk. High quality cohort-clinical trials should be conducted on different tea types and their relationship with ovarian cancer.

Coffee consumption is not associated with ovarian cancer risk: a dose-response meta-analysis of prospective cohort studies

Background

Coffee consumption has been associated with numerous cancers, but evidence on ovarian cancer risk is controversial. Therefore, we performed a meta-analysis on prospective cohort studies in order to review the evidence on coffee consumption and risk of ovarian cancer.

Methods

Studies were identified through searching the PubMed and MEDLINE databases up to March 2017. Risk estimates were retrieved from the studies, and dose-response analysis was modelled by using restricted cubic splines. Additionally, a stratified analysis by menopausal status was performed.

Results

A total of 8 studies were eligible for the dose-response meta-analysis. Studies included in the analysis comprised 787,076 participants and 3,541 ovarian cancer cases. The results showed that coffee intake was not associated with ovarian cancer risk (RR = 1.06, 95% CI: 0.89, 1.26). Stratified and subgroup analysis showed consisted results.

Conclusions

This comprehensive meta-analysis did not find evidence of an association between the consumption of coffee and risk of ovarian cancer.

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.

Coffee Drinking and Mortality in 10 European Countries: A Multinational Cohort Study

BACKGROUND

The relationship between coffee consumption and mortality in diverse European populations with variable coffee preparation methods is unclear.

OBJECTIVE

To examine whether coffee consumption is associated with all-cause and cause-specific mortality.

DESIGN

Prospective cohort study.

SETTING

10 European countries.

PARTICIPANTS

521 330 persons enrolled in EPIC (European Prospective Investigation into Cancer and Nutrition).

MEASUREMENTS

Hazard ratios (HRs) and 95% CIs estimated using multivariable Cox proportional hazards models. The association of coffee consumption with serum biomarkers of liver function, inflammation, and metabolic health was evaluated in the EPIC Biomarkers subcohort (n = 14 800).

RESULTS

During a mean follow-up of 16.4 years, 41 693 deaths occurred. Compared with nonconsumers, participants in the highest quartile of coffee consumption had statistically significantly lower all-cause mortality (men: HR, 0.88 [95% CI, 0.82 to 0.95]; P for trend < 0.001; women: HR, 0.93 [CI, 0.87 to 0.98]; P for trend = 0.009). Inverse associations were also observed for digestive disease mortality for men (HR, 0.41 [CI, 0.32 to 0.54]; P for trend < 0.001) and women (HR, 0.60 [CI, 0.46 to 0.78]; P for trend < 0.001). Among women, there was a statistically significant inverse association of coffee drinking with circulatory disease mortality (HR, 0.78 [CI, 0.68 to 0.90]; P for trend < 0.001) and cerebrovascular disease mortality (HR, 0.70 [CI, 0.55 to 0.90]; P for trend = 0.002) and a positive association with ovarian cancer mortality (HR, 1.31 [CI, 1.07 to 1.61]; P for trend = 0.015). In the EPIC Biomarkers subcohort, higher coffee consumption was associated with lower serum alkaline phosphatase; alanine aminotransferase; aspartate aminotransferase; γ-glutamyltransferase; and, in women, C-reactive protein, lipoprotein(a), and glycated hemoglobin levels.

LIMITATIONS

Reverse causality may have biased the findings; however, results did not differ after exclusion of participants who died within 8 years of baseline. Coffee-drinking habits were assessed only once.

CONCLUSION

Coffee drinking was associated with reduced risk for death from various causes. This relationship did not vary by country.

PRIMARY FUNDING SOURCE

European Commission Directorate-General for Health and Consumers and International Agency for Research on Cancer.

Smoking and risk of ovarian cancer by histological subtypes: an analysis among 300 000 Norwegian women

BACKGROUND

We prospectively investigated the association between different measures of smoking exposure and the risk of serous, mucinous, and endometrioid ovarian cancers (OC) in a cohort of more than 300 000 Norwegian women.

METHODS

We followed 300 398 women aged 19-67 years at enrolment until 31 December 2013 for OC incidence through linkage to national registries. We used Cox proportional hazards models with attained age as the underlying time scale to estimate multivariable-adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for relevant confounders.

RESULTS

During more than 5.9 million person-years and a median follow-up time of 19 years, 2336 primary invasive (1647, 71%) and borderline (689, 29%) OC were identified (53% serous, 19% mucinous). Compared with never smokers, current smokers who had smoked for ⩾10 years had a higher risk of mucinous OC (HR10-19 years vs never=1.73, 95% CI 1.24-2.42; HR⩾20 vs never=2.26, 95% CI 1.77-2.89, Ptrend <0.001). When stratified by invasiveness, current smokers had a higher risk of invasive mucinous OC (HR=1.78, 95% CI 1.20-2.64) and borderline mucinous OC (HR=2.26 95% CI, 1.71-2.97) (Pheterogeneity=0.34) than never smokers. Smoking was not associated with serous or endometrioid OC.

CONCLUSIONS

Using a very large cohort of women, the current analysis provides an important replication for a similar risk of invasive and borderline mucinous OC related to smoking.

Tea, coffee, and caffeinated beverage consumption and risk of epithelial ovarian cancers

BACKGROUND

The risk for epithelial ovarian cancer associated with the consumption of caffeinated beverages (tea, coffee, and soft drinks) and green tea is inconclusive. However, few studies have investigated the type of caffeinated beverage or the type of tea.

OBJECTIVE

We assessed consumption of tea (black/caffeinated tea and green tea separately), coffee, and caffeinated soft drinks, as well as level of consumption, and the risk for epithelial ovarian cancer and its histotypes.

STUDY DESIGN

This study was conducted within a population-based case-control study in Alberta and British Columbia, Canada from 2001 to 2012. After restricting to cases of epithelial invasive cancers and controls aged 40-79 years who completed an interview that included coffee, soft drink, and tea consumption (ascertained starting in 2005 in British Columbia and 2008 in Alberta), there were a total of 524 cases and 1587 controls. Those that did not meet the threshold for beverage consumption (at least once per month for 6 months or more) were classified as non-drinkers. Adult lifetime cumulative consumption (cup-years=cups/day*years) was calculated. Unconditional logistic regression was used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) to describe the association between the relevant drink consumption and risk.

RESULTS

No excess risk was seen for coffee or caffeinated soft drinks. Similarly, any tea consumption was not associated with risk, but when stratified by the type of tea, there was an increase in risk in black tea only drinkers (aOR=1.56; 95% CI:1.07-2.28 for >40 cup-years), but no excess risk for the exclusive green tea drinkers. Similar findings were observed for post-menopausal women. The association for black tea only consumption was mainly seen in the endometrioid histotype (aOR=3.19; 95% CI: 1.32-7.69).

CONCLUSION

Black tea consumption may be associated with an increased risk epithelial ovarian carcinoma. The excess risk is seen only in the endometrioid histotype but not in serous or clear cell. Further studies are required to confirm these findings and identify the constituents in black tea that may increase the risk.

Cancer incidence attributable to tobacco in Alberta, Canada, in 2012

BACKGROUND

Strong and consistent epidemiologic evidence shows that tobacco smoking causes cancers at various sites. The purpose of this study was to quantify the proportion and total number of site-specific cancers in Alberta attributable to tobacco exposure.

METHODS

The proportion of incident cancer cases attributable to active and passive tobacco exposure in Alberta was estimated with population attributable risks. Data from the Canadian Community Health Survey (CCHS) for 2000-2007 were used to estimate prevalence of active (current or former smoker) and passive (second-hand smoke) tobacco exposure in Alberta.

RESULTS

According to the 2000/01 CCHS, 29.1% and 38.6% of Albertans were estimated to be current and former smokers, respectively. According to the 2003 CCHS, 23.7% of Albertans who had never smoked reported regular second-hand exposure to tobacco. Population attributable risk estimates for tobacco-related cancer sites ranged from about 4% for ovarian cancer to 74% for laryngeal cancer. About 5% of incident lung cancers in men and women who never smoked could be attributed to passive tobacco exposure. Overall, 37.0% of tobacco-related cancers in Alberta (or 15.7% of all cancers) were estimated to be attributable to active tobacco smoking in 2012.

INTERPRETATION

A notable proportion of cancers associated with tobacco use were estimated to be attributable to active smoking in Alberta. Strategies to reduce the prevalence of active tobacco smoking in Alberta could have a considerable impact on future cancer incidence.

Coffee and cancer risk: A meta-analysis of prospective observational studies

Meta-analyses on coffee and cancer incidence mainly restricted to limited cancers. We carried out a more comprehensive meta-analysis of cohort studies to explore association between coffee and most cancer types. We conducted comprehensive search and summarized relative risk (RR) and 95% confidence intervals for the highest versus lowest coffee intake and cancer using STATA12. We conducted dose-analysis if result suggested significant association. The publication bias was evaluated with begg's and egger's test. Finally, 105 individual prospective studies were included. Inverse associations were observed on oral, pharyngeal, colon, liver, prostate, endometrial cancer and melanoma, with RR 0.69 (95% CI = 0.48-0.99, I² = 73.4%, P = 0.044), 0.87 (95% CI = 0.78-0.96, I² = 28.4%, P = 0.007), 0.46 (95% CI = 0.37-0.57, I² = 0%, P = 0), 0.89 (95% CI = 0.84-0.93, I² = 30.3%, P = 0.003), 0.73 (95% CI = 0.67-0.80, I²  = 0%, P = 0) and 0.89 (95% CI = 0.80-0.99, I²  = 0%, P = 0.031) respectively. However, the relative risk for lung cancer is 2.18 (95% CI = 1.26-3.75, I²  = 63.3%, P = 0.005). The summary relative risk for increment of 2 cups of coffee were RR = 0.73, 95% CI = 0.67-0.79 for liver cancer, RR = 0.97, 95% CI = 0.96-0.98 for prostate cancer and RR = 0.88, 95% CI = 0.85-0.92 for endometrial cancer. Accordingly, coffee intake was associated with reduced risk of oral, pharynx, liver, colon, prostate, endometrial cancer and melanoma and increased lung cancer risk.

Association of Ovarian Tumor β2-Adrenergic Receptor Status with Ovarian Cancer Risk Factors and Survival

BACKGROUND

The β₂-adrenergic signaling pathway mediates the effects of chronic stress on ovarian cancer progression in mouse models. The relevance of this pathway to human ovarian cancer remains unknown.

METHODS

We assessed tumor expression of β₂-adrenergic receptor (ADRB2) using tissue microarrays in 237 ovarian cancer cases from the Nurses' Health Studies (NHS/NHSII). Competing risks Cox regression was used to evaluate whether associations of reproductive, hormonal, and psychosocial factors with ovarian cancer risk differed by ADRB2. We also examined the association between tumor ADRB2 expression and ovarian cancer survival.

RESULTS

Forty-five (19%) cases were positive for ADRB2 staining. High levels of anxiety symptoms were positively associated with ADRB2-positive tumors (HR, 2.59; 95% confidence interval [CI], 1.15-5.84) but not with ADRB2-negative tumors (HR, 1.16; 95% CI, 0.81-1.66; P_{heterogeneity} = 0.07). We observed similar results for depression. No associations were observed for job strain, caregiving stress, or widowhood for either positive or negative ADRB2 status. Lifetime ovulatory years were more strongly associated with ADRB2-positive tumors (HR per 5 years, 1.60; 95% CI, 1.15-2.21) compared with ADRB2-negative tumors (HR, 1.11; 95% CI, 0.96-1.27; P_{heterogeneity} = 0.04). Significant heterogeneity by ADRB2 was also observed for parity (P_{heterogeneity} = 0.01), oral contraceptive use (P_{heterogeneity} = 0.03), and age at menopause (P_{heterogeneity} = 0.04). Tumor expression of ADRB2 was not associated with ovarian cancer mortality (HR, 1.05; 95% CI, 0.69-1.59).

CONCLUSIONS

Several stress- and ovulation-related factors were differentially associated with ovarian tumors responsive to β₂-adrenergic signaling.

IMPACT

Replication in larger studies is warranted to confirm the role of β₂-adrenergic signaling in ovarian cancer etiology. Cancer Epidemiol Biomarkers Prev; 25(12); 1587-94. ©2016 AACR.

Lifestyle changes and the risk of developing endometrial and ovarian cancers: opportunities for prevention and management

Modifiable lifestyle factors, such as obesity, lack of physical activity, and smoking, contribute greatly to cancer and chronic disease morbidity and mortality worldwide. This review appraises recent evidence on modifiable lifestyle factors in the prevention of endometrial cancer (EC) and ovarian cancer (OC) as well as new evidence for lifestyle management of EC and OC survivors. For EC, obesity continues to be the strongest risk factor, while new evidence suggests that physical activity, oral contraceptive pills, and bariatric surgery may be protective against EC. Other medications, such as metformin and nonsteroidal anti-inflammatory drugs, may be protective, and interventional research is ongoing. For OC, we find increasing evidence to support the hypothesis that obesity and hormone replacement therapy increase the risk of developing OC. Oral contraceptive pills are protective against OC but are underutilized. Dietary factors such as the Mediterranean diet and alcohol consumption do not seem to affect the risk of either OC or EC. For EC and OC survivors, physical activity and weight loss are associated with improved quality of life. Small interventional trials show promise in increasing physical activity and weight maintenance for EC and OC survivors, although the impact on long-term health, including cancer recurrence and overall mortality, is unknown. Women's health providers should integrate counseling about these modifiable lifestyle factors into both the discussion of prevention for all women and the management of survivors of gynecologic cancers.

Epithelial ovarian cancer subtypes attributable to smoking in the Norwegian Women and Cancer Study, 2012

Among European women, ovarian cancer is the fifth most common cancer. Smoking is an established risk factor for mucinous tumors. We estimated the impact of smoking in Norwegian women using population attributable fractions (PAFs) of epithelial ovarian cancer (EOC), by invasiveness and by histological subtypes in the Norwegian Women and Cancer Study with an average of 13.2 years of follow‐up. During >2 million person‐years, a total of 915 incident EOC cases, of which 667 (73%) invasive and 248 (27%) borderline, were identified among 154,234 women aged 34–70 years at enrolment. Compared with never smokers, current smokers had a nonstatistically significant increased risk of mucinous tumors (hazard ratio [HR] = 1.67 [95% confidence interval, (CI), 0.96–2.96]) and more than twice statistically significant risk of borderline mucinous tumors (HR = 2.17 [95% CI, 1.06–4.45]). The corresponding PAF estimates were 16.5% for mucinous and 25% for borderline mucinous. We found that among middle‐aged women, one in six mucinous tumors and one in four borderline mucinous tumors could have been prevented if women did not smoke.

Coffee, tea, caffeine intake, and the risk of cancer in the PLCO cohort

BACKGROUND

The association between coffee intake, tea intake and cancer has been extensively studied, but associations are not established for many cancers. Previous studies are not consistent on whether caffeine may be the source of possible associations between coffee and cancer risk.

METHODS

In the Prostate, Lung, Colorectal, and Ovarian cancer screening trial, of the 97,334 eligible individuals, 10,399 developed cancer. Cancers included were 145 head and neck, 99 oesophageal, 136 stomach, 1137 lung, 1703 breast, 257 endometrial, 162 ovarian, 3037 prostate, 318 kidney, 398 bladder, 103 gliomas, and 106 thyroid.

RESULTS

Mean coffee intake was higher in lower education groups, among current smokers, among heavier and longer duration smokers, and among heavier alcohol drinkers. Coffee intake was not associated with the risk of all cancers combined (RR=1.00, 95% confidence interval (CI)=0.96-1.05), whereas tea drinking was associated with a decreased risk of cancer overall (RR=0.95, 95% CI=0.94-0.96 for 1+ cups per day vs <1 cup per day). For endometrial cancer, a decreased risk was observed for coffee intake (RR=0.69, 95% CI=0,52-0.91 for ⩾2 cups per day). Caffeine intake was not associated with cancer risk in a dose-response manner.

CONCLUSIONS

We observed a decreased risk of endometrial cancer for coffee intake, and a decreased risk of cancer overall with tea intake.

Changing trends in the incidence of ovarian neoplasia and its relationship with the risk factors: a report of 311 cases from north-eastern anatolia region

OBJECTIVE

Ovarian cancer is one of the most common and lethal gynecologic malignancy. In Turkey, the 8(th) most commonly seen neoplasm is ovarian cancer. The risk factors of ovarian cancer are menstrual reproductive events including gravida, menarche and menopause status, and life style habits such as cigarette smoking and habitat. In this study we aimed to determine the risk factors leading to ovarian cancer in Turkish women population and show the tumor markers in this population.

MATERIALS AND METHODS

This study included 311 ovarian neoplasia cases diagnosed at the Pathology Department of Ataturk University in Erzurum over last seven years extending from 2005 to 2013. This study is a retrospective analysis basing on the pathology reports and accesible patient files. Serum tumor markers of the patients were retrospectively reported from their records. Conventional stained preparations existing in our archive examined by two pathologists as well independent of each other, and histopathologic diagnosis and the distribution of the sub-group was revised.

RESULTS

A total of 311 patients were included in this study in which patients were diagnosed at the Pathology Department of Ataturk University in Erzurum. Serous cystadenoma is the most common ovarian tumor followed by mucinous cystadenoma, germ cell tumors, and dysgerminoma. All of the tumor markers were significantly normal.

CONCLUSION

Upto our knowledge this was the first epidemiological study in Turkey. Analysis of each country's statistical information reflecting its own profile is also important. The relationship between the profiles of patients and types of ovarian neoplasia may give an idea about the risk factors of the disease in its region. Additionally, distribution of tumor markers might be considered for the discriminating of the benign or malign characters of the ovarian neoplasia.

Coffee, tea, and caffeine consumption and risk of epithelial ovarian cancer and borderline ovarian tumors: Results from a Danish case-control study

BACKGROUND

Epidemiological studies that have investigated the association between coffee, tea and caffeine consumption and ovarian cancer risk have produced conflicting results. Furthermore, only few studies have examined the role of coffee and tea consumption separately for borderline ovarian tumors. By use of data from a large Danish population-based case-control study, we examined the risk of ovarian tumors associated with coffee, tea, and caffeine consumption with a particular focus on characterizing risks by tumor behavior and histology.

MATERIAL AND METHODS

From 1995 through 1999, we included 267 women with ovarian cancer, 115 women with borderline ovarian tumors and 911 randomly selected control women. All women completed a beverage frequency questionnaire with detailed information on coffee and tea consumption. Analyses were performed using multiple logistic regression models.

RESULTS

Both coffee (OR = 0.90; 95% CI 0.84-0.97 per cup/day) and total caffeine consumption from coffee and tea combined (OR = 0.93; 95% CI 0.88-0.98 per 100 mg/day) decreased the risk of ovarian cancer. These associations were significant only for the serous and "other" subtypes of ovarian cancer. No relation between tea consumption and ovarian cancer risk was observed. The risk estimates for borderline ovarian tumors resembled those observed for ovarian cancer, but did not reach statistical significance.

CONCLUSIONS

Our results indicate that coffee consumption and total caffeine consumption from coffee and tea combined is associated with a modest decreased risk of ovarian cancer. However, more biological studies are needed to identify bioactive chemical compounds in coffee that potentially could affect ovarian cancer development.

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.

Moderate wine consumption is associated with lower hemostatic and inflammatory risk factors over 8 years: The study of women's health across the nation (SWAN)

Moderate wine consumption has been associated with reduced cardiovascular (CV) risk, but most investigations have been conducted in Caucasian populations. To investigate the relationship of wine consumption to CV risk markers, we studied a multi-ethnic sample of middle-aged, healthy women (N = 2900; 48% white, 28% black, 7% Hispanic, 8% Chinese, 9% Japanese) participating in SWAN over 7 years with repeated assessments of CV risk factors. Consumption of wine was stable and common with 20% reporting none, 69% light (<1/day), 7% moderate ( = 1/day), and 4% heavy (>1/day). To guard against underreporting, we took the maximum reported wine consumption over 7 years as the predictor. We used mixed models with a random intercept and random time to assess the relationship between wine consumption and CV risk factors with moderate consumption as the reference. Outcome variables were log-transformed where necessary. Longitudinal models were adjusted for ethnicity, age, and time-varying menopausal status, hormone therapy use, overall alcohol consumption, high density lipoprotein (HDL), statin use, and a healthy lifestyle score based on physical activity, not smoking, and weight maintenance. Interactions of wine consumption with time were not significant. Moderate wine consumers had significantly lower levels of C-reactive protein (CRP, p < .001), fibrinogen (p < .001), factor VII (p < .01), and plasminogen activator inhibitor (PAI-1, p < .05) than women who drank no or little wine. These associations were independent of significant effects of healthy lifestyle and overall alcohol consumption and similar across ethnic groups. Moderate wine consumption may protect against CVD via inflammatory and clotting pathways.

Characterization of chemically induced ovarian carcinomas in an ethanol-preferring rat model: influence of long-term melatonin treatment

Ovarian cancer is the fourth most common cause of cancer deaths among women, and chronic alcoholism may exert co-carcinogenic effects. Because melatonin (mel) has oncostatic properties, we aimed to investigate and characterize the chemical induction of ovarian tumors in a model of ethanol-preferring rats and to verify the influence of mel treatment on the overall features of these tumors. After rats were selected to receive ethanol (EtOH), they were surgically injected with 100 µg of 7,12-dimethyl-benz[a]anthracene (DMBA) plus sesame oil directly under the left ovarian bursa. At 260 days old, half of the animals received i.p. injections of 200 µg mel/100 g b.w. for 60 days. Four experimental groups were established: Group C, rats bearing ovarian carcinomas (OC); Group C+EtOH, rats voluntarily consuming 10% (v/v) EtOH and bearing OC; Group C+M, rats bearing OC and receiving mel; and Group C+EtOH+M, rats with OC consuming EtOH and receiving mel. Estrous cycle and nutritional parameters were evaluated, and anatomopathological analyses of the ovarian tumors were conducted. The incidence of ovarian tumors was higher in EtOH drinking animals 120 days post-DMBA administration, and mel efficiently reduced the prevalence of some aggressive tumors. Although mel promoted high EtOH consumption, it was effective in synchronizing the estrous cycle and reducing ovarian tumor mass by 20%. While rats in the C group displayed cysts containing serous fluid, C+EtOH rats showed solid tumor masses. After mel treatment, the ovaries of these rats presented as soft and mobile tissues. EtOH consumption increased the incidence of serous papillary carcinomas and sarcomas but not clear cell carcinomas. In contrast, mel reduced the incidence of sarcomas, endometrioid carcinomas and cystic teratomas. Combination of DMBA with EtOH intake potentiated the incidence of OC with malignant histologic subtypes. We concluded that mel reduces ovarian masses and the incidence of adenocarcinomas in ethanol-deprived rats.

Coffee and tea consumption in relation to prostate cancer prognosis

BACKGROUND

Bioactive compounds found in coffee and tea may delay the progression of prostate cancer.

METHODS

We investigated associations of pre-diagnostic coffee and tea consumption with risk of prostate cancer recurrence/progression. Study participants were men diagnosed with prostate cancer in 2002-2005 in King County, Washington, USA. We assessed the usual pattern of coffee and tea consumption two years before diagnosis date. Prostate cancer-specific outcome events were identified using a detailed follow-up survey. Multivariable Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs).

RESULTS

The analysis of coffee intake in relation to prostate cancer recurrence/progression included 630 patients with a median follow-up of 6.4 years, during which 140 prostate cancer recurrence/progression events were recorded. Approximately 61 % of patients consumed at least one cup of coffee per day. Coffee consumption was associated with a reduced risk of prostate cancer recurrence/progression; the adjusted HR for ≥4 cups/day versus ≤1 cup/week was 0.41 (95 % CI: 0.20, 0.81; p for trend = 0.01). Approximately 14 % of patients consumed one or more cups of tea per day, and tea consumption was unrelated to prostate cancer recurrence/progression.

CONCLUSION

Results indicate that higher pre-diagnostic coffee consumption is associated with a lower risk of prostate cancer recurrence/progression. This finding will require replication in larger studies.

Cigarette smoking and risk of ovarian cancer: a pooled analysis of 21 case-control studies

PURPOSE

The majority of previous studies have observed an increased risk of mucinous ovarian tumors associated with cigarette smoking, but the association with other histological types is unclear. In a large pooled analysis, we examined the risk of epithelial ovarian cancer associated with multiple measures of cigarette smoking with a focus on characterizing risks according to tumor behavior and histology.

METHODS

We used data from 21 case-control studies of ovarian cancer (19,066 controls, 11,972 invasive and 2,752 borderline cases). Study-specific odds ratios (OR) and 95 % confidence intervals (CI) were obtained from logistic regression models and combined into a pooled odds ratio using a random effects model.

RESULTS

Current cigarette smoking increased the risk of invasive mucinous (OR = 1.31; 95 % CI: 1.03-1.65) and borderline mucinous ovarian tumors (OR = 1.83; 95 % CI: 1.39-2.41), while former smoking increased the risk of borderline serous ovarian tumors (OR = 1.30; 95 % CI: 1.12-1.50). For these histological types, consistent dose-response associations were observed. No convincing associations between smoking and risk of invasive serous and endometrioid ovarian cancer were observed, while our results provided some evidence of a decreased risk of invasive clear cell ovarian cancer.

CONCLUSIONS

Our results revealed marked differences in the risk profiles of histological types of ovarian cancer with regard to cigarette smoking, although the magnitude of the observed associations was modest. Our findings, which may reflect different etiologies of the histological types, add to the fact that ovarian cancer is a heterogeneous disease.

Acrylamide hemoglobin adduct levels and ovarian cancer risk: a nested case-control study

BACKGROUND

Acrylamide is a probable human carcinogen formed during cooking of starchy foods. Two large prospective cohort studies of dietary acrylamide intake and ovarian cancer risk observed a positive association, although two other studies reported no association.

METHODS

We measured acrylamide exposure using red blood cell acrylamide and glycidamide hemoglobin adducts among women in two large prospective cohorts: the Nurses' Health Study and Nurses' Health Study II. Between blood collection and 2010, we identified 263 incident cases of epithelial ovarian cancer, matching two controls per case. We used logistic regression models to examine the association between acrylamide exposure and ovarian cancer risk, adjusting for matching factors, family history of ovarian cancer, tubal ligation, oral contraceptive use, body mass index, parity, alcohol intake, smoking, physical activity, and caffeine intake.

RESULTS

The multivariate-adjusted relative risk (RR) of ovarian cancer comparing the highest versus lowest tertile of total acrylamide adducts was 0.79 (95% CI, 0.50-1.24, P trend = 0.08). The comparable RR of ovarian cancer among non-smokers at blood draw was 0.85 (95% CI, 0.57-1.27, P trend = 0.14). The association did not differ by tumor histology (serous invasive versus not), P for heterogeneity = 0.86. Individual adduct types (acrylamide or glycidamide) were not associated with risk.

CONCLUSIONS

We observed no evidence that acrylamide exposure as measured by adducts to hemoglobin is associated with an increased risk of ovarian cancer.

IMPACT

Our finding indicates that acrylamide intake may not increase risk of ovarian cancer.

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.

Non-steroidal anti-inflammatory drug use and ovarian cancer risk: findings from the NIH-AARP Diet and Health Study and systematic review

BACKGROUND

Chronic inflammation has been proposed as a risk factor for ovarian cancer. Some data suggest that anti-inflammatory medications may be protective against ovarian cancer; however, results have been inconsistent.

METHODS

We evaluated the risk of epithelial ovarian cancer with regular use of NSAIDs prospectively in the NIH-AARP Diet and Health Study, using Cox proportional hazard models. We also examined the risk of common subtypes of epithelial ovarian cancer (serous, mucinous, endometrioid, clear cell, and other epithelial) with regular use of NSAIDs. In addition, we performed meta-analyses summarizing the risk of ovarian cancer with "regular use" of NSAIDs in previously published studies.

RESULTS

We did not observe a significant association between regular use of NSAIDs with ovarian cancer risk in the AARP cohort (aspirin: RR 1.06, 95 % CI 0.87-1.29; non-aspirin NSAIDs: RR 0.93, 95 % CI 0.74-1.15); however, summary estimates from prospective cohort studies demonstrated that use of non-aspirin NSAIDs may reduce the risk of ovarian cancer (RR 0.88, 95 % CI 0.77-1.01). Although not significant, we found that mucinous tumors were inversely associated with non-aspirin NSAID use (RR 0.69, 95 % CI 0.23-2.10) in the AARP cohort, which was supported by the meta-analysis (RR 0.69, CI 0.50-0.94.)

CONCLUSION

Although results from the NIH-AARP cohort study were not statistically significant, our meta-analysis suggests that non-aspirin NSAIDs may be protective against ovarian cancer. Additional analyses, focusing on dose, duration, and frequency of NSAID use and accounting for ovarian cancer heterogeneity are necessary to further elucidate the association between NSAID use and ovarian cancer risk.

Ovarian cancer and smoking: individual participant meta-analysis including 28,114 women with ovarian cancer from 51 epidemiological studies

Background

Smoking has been linked to mucinous ovarian cancer, but its effects on other ovarian cancer subtypes and on overall ovarian cancer risk are unclear, and the findings from most studies with relevant data are unpublished. To assess these associations, we review the published and unpublished evidence.

Methods

Eligible epidemiological studies were identified by electronic searches, review articles, and discussions with colleagues. Individual participant data for 28 114 women with and 94 942 without ovarian cancer from 51 epidemiological studies were analysed centrally, yielding adjusted relative risks (RRs) of ovarian cancer in smokers compared with never smokers.

Findings

After exclusion of studies with hospital controls, in which smoking could have affected recruitment, overall ovarian cancer incidence was only slightly increased in current smokers compared with women who had never smoked (RR 1·06, 95% CI 1·01–1·11, p=0·01). Of 17 641 epithelial cancers with specified histology, 2314 (13%) were mucinous, 2360 (13%) endometrioid, 969 (5%) clear-cell, and 9086 (52%) serous. Smoking-related risks varied substantially across these subtypes (p_{heterogeneity}<0·0001). For mucinous cancers, incidence was increased in current versus never smokers (1·79, 95% CI 1·60–2·00, p<0·0001), but the increase was mainly in borderline malignant rather than in fully malignant tumours (2·25, 95% CI 1·91–2·65 vs 1·49, 1·28–1·73; p_{heterogeneity}=0·01; almost half the mucinous tumours were only borderline malignant). Both endometrioid (0·81, 95% CI 0·72–0·92, p=0·001) and clear-cell ovarian cancer risks (0·80, 95% CI 0·65–0·97, p=0·03) were reduced in current smokers, and there was no significant association for serous ovarian cancers (0·99, 95% CI 0·93–1·06, p=0·8). These associations did not vary significantly by 13 sociodemographic and personal characteristics of women including their body-mass index, parity, and use of alcohol, oral contraceptives, and menopausal hormone therapy.

Interpretation

The excess of mucinous ovarian cancers in smokers, which is mainly of tumours of borderline malignancy, is roughly counterbalanced by the deficit of endometrioid and clear-cell ovarian cancers. The substantial variation in smoking-related risks by tumour subtype is important for understanding ovarian carcinogenesis.

Funding

Cancer Research UK and MRC.

Ovarian cancer: etiology, risk factors, and epidemiology

Little is known regarding the early aspects of ovarian carcinogenesis. As a consequence, the identification of women at risk for the disease is based primarily on clinical grounds, with family history being the most important risk factor. In this review, we will discuss the various hypotheses regarding ovarian etiology and pathogenesis. In addition, we will discuss the epidemiology of ovarian cancer, including hereditary, reproductive, hormonal, inflammatory, dietary, surgical, and geographic factors that influence ovarian cancer risk.

Using bioinformatic approaches to identify pathways targeted by human leukemogens

We have applied bioinformatic approaches to identify pathways common to chemical leukemogens and to determine whether leukemogens could be distinguished from non-leukemogenic carcinogens. From all known and probable carcinogens classified by IARC and NTP, we identified 35 carcinogens that were associated with leukemia risk in human studies and 16 non-leukemogenic carcinogens. Using data on gene/protein targets available in the Comparative Toxicogenomics Database (CTD) for 29 of the leukemogens and 11 of the non-leukemogenic carcinogens, we analyzed for enrichment of all 250 human biochemical pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The top pathways targeted by the leukemogens included metabolism of xenobiotics by cytochrome P450, glutathione metabolism, neurotrophin signaling pathway, apoptosis, MAPK signaling, Toll-like receptor signaling and various cancer pathways. The 29 leukemogens formed 18 distinct clusters comprising 1 to 3 chemicals that did not correlate with known mechanism of action or with structural similarity as determined by 2D Tanimoto coefficients in the PubChem database. Unsupervised clustering and one-class support vector machines, based on the pathway data, were unable to distinguish the 29 leukemogens from 11 non-leukemogenic known and probable IARC carcinogens. However, using two-class random forests to estimate leukemogen and non-leukemogen patterns, we estimated a 76% chance of distinguishing a random leukemogen/non-leukemogen pair from each other.

CYP1A2 and coffee intake and the modifying effect of sex, age, and smoking

BACKGROUND

The enzyme CYP1A2 (cytochrome 1A2) is involved in the metabolism of certain drugs and caffeine, and its activity can be influenced by factors such as sex, age, and smoking. The single nucleotide polymorphism (SNP) rs762551A>C, which has also been studied for its modifying effect on cardiovascular disease, has been reported to alter enzyme activity.

OBJECTIVE

The objective was to study the effect of CYP1A2, sex, age, and smoking on coffee intake.

DESIGN

Within the Rotterdam Study, a population-based cohort, all coffee drinkers for whom genome-wide association data were available were selected. Because SNP rs762551 was not on the Illumina 550 platform, SNP rs2472299 was used as a proxy, with the A allele of rs762551 linked to the G allele of rs2472299. Linear regression analyses were used to determine the effect and interaction of rs2472299, sex, age, and smoking on coffee intake. Adjusted geometric means of coffee intake were calculated per genotype for the different smoking and sex strata by using multivariable general linear models. A combined analysis, with the use of a "risk score," was performed to determine the contribution of each separate factor.

RESULTS

rs2472299G>A, female sex, and nonsmoking were significantly inversely related to coffee intake. Coffee intake was lowest in nonsmoking women homozygous for rs2472299G>A (3.49 cups/d; ∼436 mL). All factors contributed almost linearly to the intake of coffee, with the highest coffee intake in smoking men without the A allele (5.32 cups/d; ∼665 mL).

CONCLUSION

rs2472299G>A, linked to rs762551A>C, sex, age, and smoking significantly contribute to coffee intake.

Green tea for ovarian cancer prevention and treatment: a systematic review of the in vitro, in vivo and epidemiological studies

OBJECTIVE

This systematic review was conducted to examine the effects of green tea or green tea components on the prevention and progression of epithelial ovarian cancer.

METHODS

Using Medline, EMBASE and SciVerse (last researched: July 2011), we retrieved 22 articles including 5 epidemiological studies.

RESULTS

In epithelial ovarian cancer cell lines, green tea and green tea components have been shown to downregulate the expression of proteins involved in inflammation, cell signalization, cell motility and angiogenesis. Green tea and green tea components would induce apoptosis and could potentiate the effects of cisplatin, a chemotherapeutic agent. In human observational studies, significant associations between green tea intake and both decreased ovarian cancer occurrence and better prognosis were reported.

CONCLUSIONS

Available literature suggests potential molecular targets for green tea in ovarian cancer treatment and also provides data supporting the clinical evaluation of the role of green tea or green tea components in ovarian cancer prevention and treatment.

Coffee and tea consumption and the risk of ovarian cancer: a prospective cohort study and updated meta-analysis

BACKGROUND

In 2007 the World Cancer Research Fund Report concluded that there was limited and inconsistent evidence for an effect of coffee and tea consumption on the risk of epithelial ovarian cancer (EOC).

OBJECTIVE

In the European Prospective Investigation into Cancer and Nutrition (EPIC), we aimed to investigate whether coffee intakes, tea intakes, or both are associated with the risk of EOC.

DESIGN

All women participating in the EPIC (n = 330,849) were included in this study. Data on coffee and tea consumption were collected through validated food-frequency questionnaires at baseline. HRs and 95% CIs were estimated by using Cox proportional hazards models. Furthermore, we performed an updated meta-analysis of all previous prospective studies until April 2011 by comparing the highest and lowest coffee- and tea-consumption categories as well as by using dose-response random-effects meta-regression analyses.

RESULTS

During a median follow-up of 11.7 y, 1244 women developed EOC. No association was observed between the risk of EOC and coffee consumption [HR: 1.05 (95% CI: 0.75, 1.46) for the top quintile compared with no intake] or tea consumption [HR: 1.07 (95% CI: 0.78, 1.45) for the top quintile compared with no intake]. This lack of association between coffee and tea intake and EOC risk was confirmed by the results of our meta-analysis.

CONCLUSION

Epidemiologic studies do not provide sufficient evidence to support an association between coffee and tea consumption and risk of ovarian cancer.

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.

Caffeinated beverage intake and reproductive hormones among premenopausal women in the BioCycle Study

BACKGROUND

Caffeinated beverages are widely consumed among women of reproductive age, but their association with reproductive hormones, and whether race modifies any such associations, is not well understood.

OBJECTIVE

We assessed the relation between caffeine and caffeinated beverage intake and reproductive hormones in healthy premenopausal women and evaluated the potential effect modification by race.

DESIGN

Participants (n = 259) were followed for up to 2 menstrual cycles and provided fasting blood specimens for hormonal assessment at up to 8 visits per cycle and four 24-h dietary recalls per cycle. Weighted linear mixed models and nonlinear mixed models with harmonic terms were used to estimate associations between caffeine and hormone concentrations, adjusted for age, adiposity, physical activity, energy and alcohol intakes, and perceived stress. On the basis of a priori assumptions, an interaction between race and caffeine was tested, and stratified results are presented.

RESULTS

Caffeine intake ≥200 mg/d was inversely associated with free estradiol concentrations among white women (β = -0.15; 95% CI: -0.26, -0.05) and positively associated among Asian women (β = 0.61; 95% CI: 0.31, 0.92). Caffeinated soda intake and green tea intake ≥1 cup/d (1 cup = 240 mL) were positively associated with free estradiol concentrations among all races: β = 0.14 (95% CI: 0.06, 0.22) and β = 0.26 (95% CI: 0.07, 0.45), respectively.

CONCLUSIONS

Moderate consumption of caffeine was associated with reduced estradiol concentrations among white women, whereas caffeinated soda and green tea intakes were associated with increased estradiol concentrations among all races. Further research is warranted on the association between caffeine and caffeinated beverages and reproductive hormones and whether these relations differ by race.