Oral contraceptive use and reproductive factors and risk of ovarian cancer in the European Prospective Investigation into Cancer and Nutrition

Quantitative analysis of 34 sex (pro)hormones, conjugates and bioactive oxidation products thereof in human plasma by GC- and LC-MS/MS and systematic investigation of overestimations of analyte concentrations not accounted for by method validation

When investigating endocrine disorders, it is essential to assess a comprehensive quantitative profile of sex (pro)hormones in plasma including conjugates. Thus, the present study aimed to develop and validate a comprehensive mass spectrometry-based multimethod combining the direct analysis of unconjugated sex (pro)hormones and oxidation products thereof (by GC), as well as their sulfates and glucuronides present in higher concentrations (by LC) with the indirect quantification of glucuronides present in lower concentrations after selective glucuronide hydrolysis (by GC) and its application to plasma derived from ten pre- and postmenopausal women and men each. Even guideline-compliant validation experiments cannot completely reflect overestimation of analyte concentrations due to effects depending on the individual ratio of analytes (i.e. chemical formation of analytes or incomplete removal of interfering analytes). Thus, the extent of processes not accounted for by the calibration strategy were investigated and maximum over- or underestimations of analyte concentrations were assessed for each plasma sample individually. 34 analytes were successfully calibrated, validated (median accuracy 101.1 %, median inter-day precision 8.1 %) and 31 were detected above the detection limit in plasma samples. The sporadic maximum individual over- or underestimation of analyte concentrations amounted to less than 20 %.

An epigenetic hypothesis for ovarian cancer prevention by oral contraceptive pill use

BACKGROUND

Ovarian cancer is the second most common gynecological cancer type after uterine cancers. In 2020, according to worldwide statistics, there were more than 313,000 new cases of ovarian cancer. Most concerning with ovarian cancer is the poor overall survival, with only 30% of patients surviving for longer than 5 years after diagnosis. The reason for this poor outcome includes late diagnosis due to non-specific symptoms and a lack of any highly effective biomarkers of the early stages of ovarian carcinogenesis. However, it is important to note that some modifiable lifestyle factors can be preventative [pregnancy, breastfeeding and combined oral contraceptives pill (COCP) use].

RESULTS

There is now increasing data reporting the role of epigenetic changes, which are detectable in ovarian cancer tumors, suggesting the possibility that epigenetics may also play a key role in the mechanism of long-term effective prevention of ovarian cancer. To our knowledge, there is a lack of high-quality data on the molecular mechanisms of ovarian cancer prevention, although several hypotheses have been proposed.

CONCLUSIONS

This review focusses on the evidence for a proposed novel hypothesis-that COCPs act as a chemoprevention through the impact on the epigenome of the cells of origin of ovarian cancer-fallopian tubes epithelium.

Review of mendelian randomization studies on age at natural menopause

Menopause marks the end of the reproductive phase of life. Based on epidemiological studies, abnormal age at natural menopause (ANM) is thought to contribute to a number of adverse outcomes, such as osteoporosis, cardiovascular disease, and cancer. However, the causality of these associations remains unclear. A powerful epidemiological method known as Mendelian randomization (MR) can be used to clarify the causality between ANM and other diseases or traits. The present review describes MR studies that included ANM as an exposure, outcome and mediator. The findings of MR analyses on ANM have revealed that higher body mass index, poor educational level, early age at menarche, early age at first live birth, early age at first sexual intercourse, and autoimmune thyroid disease appear to be involved in early ANM etiology. The etiology of late ANM appears to be influenced by higher free thyroxine 4 and methylene tetrahydrofolate reductase gene mutations. Furthermore, early ANM has been found to be causally associated with an increased risk of osteoporosis, fracture, type 2 diabetes mellitus, glycosylated hemoglobin, and the homeostasis model of insulin resistance level. In addition, late ANM has been found to be causally associated with an increased systolic blood pressure, higher risk of breast cancer, endometrial cancer, endometrioid ovarian carcinoma, lung cancer, longevity, airflow obstruction, and lower risk of Parkinson's disease. ANM is also a mediator for breast cancer caused by birth weight and childhood body size. However, due to the different instrumental variables used, some results of studies are inconsistent. Future studies with more valid genetic variants are needed for traits with discrepancies between MRs or between MR and other types of epidemiological studies.

Ovarian and Endometrial Endometrioid Carcinoma Following the Use of a Biologic IL-17 Inhibitor

Evidence suggests that IL-17, a pro-inflammatory cytokine, suppresses tumor carcinogenesis; therefore, the use of IL-17 inhibitors accelerates carcinoma growth. We present a case of a perimenopausal female who was diagnosed with synchronous primary ovarian and endometrial endometrioid carcinoma following the use of secukinumab, a monoclonal antibody against IL-17. After eight months of secukinumab, she developed progressive vaginal bleeding, left upper quadrant pain, and abdominal distention. CT imaging displayed a large abdominal mass, and biopsies produced the diagnosis. It is proposed that by inhibiting IL-17, carcinogenesis was expedited. This case highlights a relationship between secukinumab and accelerated carcinogenesis. Consequently, due to the incidence of endometrial carcinoma and the morbidity rate of ovarian carcinoma, individuals taking IL-17 inhibitors may need prophylactic screening and close monitoring.

Repeated Rounds of Gonadotropin Stimulation Induce Imbalance in the Antioxidant Machinery and Activation of Pro-Survival Proteins in Mouse Oviducts

Controlled ovarian stimulation (COS) through gonadotropin administration has become a common procedure in assisted reproductive technologies. COS's drawback is the formation of an unbalanced hormonal and molecular environment that could alter several cellular mechanisms. On this basis, we detected the presence of mitochondrial DNA (mtDNA) fragmentation, antioxidant enzymes (catalase; superoxide dismutases 1 and 2, SOD-1 and -2; glutathione peroxidase 1, GPx1) and apoptotic (Bcl-2-associated X protein, Bax; cleaved caspases 3 and 7; phosphorylated (p)-heat shock protein 27, p-HSP27) and cell-cycle-related proteins (p-p38 mitogen-activated protein kinase, p-p38 MAPK; p-MAPK activated protein kinase 2, p-MAPKAPK2; p-stress-activated protein kinase/Jun amino-terminal kinase, p-SAPK/JNK; p-c-Jun) in the oviducts of unstimulated (Ctr) and repeatedly hyperstimulated (eight rounds, 8R) mice. While all the antioxidant enzymes were overexpressed after 8R of stimulation, mtDNA fragmentation decreased in the 8R group, denoting a present yet controlled imbalance in the antioxidant machinery. Apoptotic proteins were not overexpressed, except for a sharp increase in the inflammatory-related cleaved caspase 7, accompanied by a significant decrease in p-HSP27 content. On the other hand, the number of proteins involved in pro-survival mechanisms, such as p-p38 MAPK, p-SAPK/JNK and p-c-Jun, increased almost 50% in the 8R group. Altogether, the present results demonstrate that repeated stimulations cause the activation of the antioxidant machinery in mouse oviducts; however, this is not sufficient to induce apoptosis, and is efficiently counterbalanced by activation of pro-survival proteins.

Trends in the incidence of ovarian cancer in sub-Saharan Africa

Ovarian cancer (OC) is one of the commonest cancers of women in sub-Saharan Africa (SSA), although to date no data have been available on time trends in incidence to better understand the disease pattern in the region. We estimate time trends by histological subtype from 12 population-based cancer registries in 11 countries: Kenya (Nairobi), Mauritius, Seychelles, Uganda (Kampala), Congo (Brazzaville), Zimbabwe (Bulawayo and Harare), Cote d'Ivoire (Abidjan), The Gambia, Mali (Bamako), Nigeria (Ibadan) and South Africa (Eastern Cape). The selected registries were those that could provide consistent estimates of the incidence of ovarian cancer and with quality assessment for periods of 10 or more years. A total of 5423 cases of OC were included. Incidence rates have been increasing in all registries except Brazzaville, Congo, where a nonsignificant decline of 1% per year was seen. Statistically significant average annual increases were seen in Mauritius (2.5%), Bamako (5.3%), Ibadan (3.9%) and Eastern Cape (8%). Epithelial ovarian cancer was responsible for the increases observed in all registries. Statistically significant average annual percentage changes (AAPC) for epithelial OC were present in Bamako (AAPC = 5.9%), Ibadan (AAPC = 4.7%) and Eastern Cape (AAPC = 11.0%). Creating awareness among professionals of the growing importance of the disease is surely an important step to improving availability of, and access to, diagnosis and treatment of OC in SSA. Support must be given to the cancer registries to improve the availability of good-quality data on this important cancer.

Sex steroid hormones and DNA repair regulation: Implications on cancer treatment responses

The role of sex steroid hormones (SSHs) has been shown to modulate cancer cytotoxic treatment sensitivity. Dysregulation of DNA repair associated with genomic instability, abnormal cell survival and not only promotes cancer progression but also resistance to cancer treatment. The three major SSHs, androgen, estrogen, and progesterone, have been shown to interact with several essential DNA repair components. The presence of androgens directly regulates key molecules in DNA double-strand break (DSB) repair. Estrogen can promote cell proliferation and DNA repair, allowing cancer cells to tolerate chemotherapy and radiotherapy. Information on the role of progesterone in DNA repair is limited: progesterone interaction with some DNA repair components has been identified, but the biological significance is still unknown. Here, we review the roles of how each SSH affects DNA repair regulation and modulates response to genotoxic therapies and discuss future research that can be beneficial when combining SSHs with cancer therapy. We also provide preliminary analysis from publicly available databases defining the link between progesterone/PR and DDRs & DNA repair regulation that plausibly contribute to chemotherapy response and breast cancer patient survival.

Nanotechnology-Based Nucleic Acid Vaccines for Treatment of Ovarian Cancer

Anticancer vaccines represent a promising approach for effective treatment of cancer and along with recent advantages of nucleic acid-based vaccines for other diseases form a prospective and potentially efficacious direction of the research, development and clinical applications. Despite the ongoing several clinical trials of mRNA vaccines for the treatment of various types of cancer, to-date no cancer vaccines were approved by the US Food and Drug Administration. The present review analyzes and summarizes major approaches for treating of different forms of ovarian cancer including mRNA-based vaccines as well as nanotechnology-based approaches for their delivery.

Validation of a GC- and LC-MS/MS based method for the quantification of 22 estrogens and its application to human plasma

In epidemiological studies, blood levels of 17β-estradiol (E2) are associated with hormone-dependent diseases. The lack of specific methods impedes studies on the role of E2 metabolites and their conjugates in the etiology of hormone-dependent diseases. Stable-isotope dilution tandem mass spectrometry methods (coupled to gas chromatography and liquid chromatography systems) for the analysis of 22 endogenous estrogens, including both oxidative metabolites, as well as sulfates and glucuronides, was validated and the method applied to plasma of women with no breast cancer. No changes in estrogen profile during sample cleanup were observed and values for limit of detection (7fmol/ml - 2 pmol/ml), accuracies (80-122%) as well as intra- and inter-day precision (below 28%) at levels near the limit of quantification were acceptable. In human plasma only seven estrogens were detected and estrone conjugates contributed most to the estrogen profile.

Dietary lactose and galactose intakes are associated with a later onset of natural menopause among women in a Japanese community

Galactose and its metabolites, primarily derived from lactose, may have toxic effects on the ovary. We aimed to prospectively examine the associations of galactose and lactose intakes with the onset of natural menopause. The data of a population-based cohort study in a Japanese community (the Takayama study) initiated in 1992 were analysed, with follow-up data collected in 2002. Among the participants of the Takayama study, premenopausal women (n 3115) aged 35-56 years at baseline were included in this study. Dietary intake, including lactose and galactose was assessed only at baseline using a FFQ. The menopausal status and age at menopause were determined based on the participants' self-reports, and natural menopause was defined as the absence of menstruation for 12 months or more. Cox proportional hazards models were used to estimate the hazard ratios (HR) and 95 % CI. A total of 1790 women experienced natural menopause within the 10-year follow-up. Lactose and galactose intakes were associated with a later onset of natural menopause after adjusting for potential confounding factors and the HR (95 % CI) for the highest v. lowest quartile were 0·80 (0·69, 0·92) (P-trend = 0·001) in lactose and 0·86 (0·74, 1·00) in galactose (P-trend = 0·036), respectively. High intakes of lactose and galactose were associated with a later onset of natural menopause. Despite the presumed ovotoxicity effects, lactose and galactose intakes at usual levels may not be deleterious to the ovarian aging process among Japanese community-dwelling women.

Microscopic Evaluation of Ovarian Surface Epithelium Following Treatment with Conjugated Estrogens in a Mouse Model

BACKGROUND

This study was designed to evaluate the effect of different concentrations of conjugated equine estrogens (CEE) on the ovarian epithelium of female CD1 mice.

METHODS

Twenty-four female mice at 7 months with irregular estrus cycles were randomly divided into four groups of 6 mice each. Group one was considered as a control group and received a daily dose of 0.5ml of propylene glycol, for three weeks, while those in the treatment groups received a daily dose of 14μg/kg, 28μg/kg and 56μg/kg conjugated equine estrogens, respectively.

RESULTS

The results from this study showed a strong correlation between elevated concentrations of CEE and histological changes in ovarian surface epithelium (OSE). They also showed that administration of high-dose estrogen created the conditions for excessive proliferation of OSE which may progress into the development of cysts in the ovaries.

CONCLUSION

This study concluded that high concentrations of CEE may increase the chances of developing epithelial ovarian cancer.

Risk Factors for Ovarian Cancer: An Umbrella Review of the Literature

Several non-genetic factors have been associated with ovarian cancer incidence or mortality. To evaluate the strength and validity of the evidence we conducted an umbrella review of the literature that included systematic reviews/meta-analyses that evaluated the link between non-genetic risk factors and ovarian cancer incidence and mortality. We searched PubMed, EMBASE, Cochrane Database of Systematic Reviews and performed a manual screening of references. Evidence was graded into strong, highly suggestive, suggestive or weak based on statistical significance of the random effects summary estimate and the largest study in a meta-analysis, the number of cases, between-study heterogeneity, 95% prediction intervals, small study effects, and presence of excess significance bias. We identified 212 meta-analyses, investigating 55 non-genetic risk factors for ovarian cancer. Risk factors were grouped in eight broad categories: anthropometric indices, dietary intake, physical activity, pre-existing medical conditions, past drug history, biochemical markers, past gynaecological history and smoking. Of the 174 meta-analyses of cohort studies assessing 44 factors, six associations were graded with strong evidence. Greater height (RR per 10 cm 1.16, 95% confidence interval (CI) 1.11-1.20), body mass index (BMI) (RR ≥ 30 kg/m² versus normal 1.27, 95% CI 1.17-1.38) and three exposures of varying preparations and usage related to hormone replacement therapy (HRT) use increased the risk of developing ovarian cancer. Use of oral contraceptive pill reduced the risk (RR 0.74, 95% CI 0.69-0.80). Refining the significance of genuine risk factors for the development of ovarian cancer may potentially increase awareness in women at risk, aid prevention and early detection.

Assessment of gynecological and lifestyle-related risk factors of ovarian cancer

INTRODUCTION

Ovarian cancer remains the most lethal gynecological cancer. Assessment of gynecological and lifestyle-related risk factors is essential to reduce the occurrence and the mortality rate of the disease.

MATERIAL AND METHODS

Surveys were collected among 71 patients with ovarian cancer and 76 women without gynecological cancer. Questionnaires included questions about medical history and lifestyle in the past.

RESULTS

The control group had breastfed longer (p = 0.034) and used hormonal contraception more often (p = 0.00037) than the study group. The patients in FIGO (French. Fédération internationale de gynécologie et d'obstétrique) stage III or IV had a higher number of lifetime ovulatory cycles (p = 0.001) than the control group. Women at FIGO stage IV slept significantly less than patients at other stages (p = 0.0026). Oncological patients reporting sedentary work more often were diagnosed at advanced stages (p = 0.00328). The risk of ovarian cancer was 0.046 times smaller for women who had given birth (p = 0.025), 0.94 times smaller for every one month longer breastfeeding (p = 0.0428), 0.677 times smaller for every one year older age at menarche (p = 0.0152), 0.106 times smaller for women who had used hormonal contraception (p = 0.0019), and 5.46 times higher for women who ever worked night shifts (p = 0.0128).

CONCLUSIONS

Our study proves the importance of both gynecological and lifestyle-related risk factors of ovarian cancer and their impact on its prevalence. Lifestyle-related risk factors cannot be ignored, as they might have a direct influence on the aggravation of the risk of this type of cancer. Promoting an adequate amount of physical activity and sleep, breastfeeding, and having children could improve the detection and treatment of ovarian cancer in general.

The influence of endogenous and exogenous hormonal factors on migraine in spontaneous postmenopausal women: A nationwide population-based study in South Korea

BACKGROUND

Hormonal and menstrual factors are known to influence migraines in women. However, studies in the postmenopausal period are relatively insufficient for clinical translation. This study investigated the influence of endogenous and exogenous hormonal factors on migraines in spontaneous menopausal women.

METHODS

We obtained and analyzed the data related to hormonal factors from the Korean Health Examination database. A migraine diagnosis was identified using the Korean National Health Insurance Service database between 2009 and 2018. We observed migraine occurrence in spontaneous postmenopausal women. Study populations were divided into two groups depending on new diagnosis of migraine during the follow up periods. We investigated the association between endogenous and exogenous hormonal factors and migraine.

RESULTS

1,114,742 spontaneous postmenopausal women were enrolled. Migraine risk tended to increase in the shorter lifetime number of years of menstruation group compared to the group with lifetime number of years of menstruation ≥40 years. All of the hormone replacement therapy (HRT) groups showed higher risk compared with the non-HRT group. Migraine risk tends to increase with greater postmenopausal years compared to the postmenopausal <5 years group.

CONCLUSION

Our study suggests that female hormonal factors, including endogenous and exogenous estrogen exposure, may be associated with migraine occurrence in spontaneous menopausal women.

Hormonally Active Contraceptives, Part II: Sociological, Environmental, and Economic Impact

To investigate the sociological, environmental, and economic impact of hormonally active contraceptives, a series of comprehensive literature surveys were employed. Sociological effects are discussed including abortion, exploitation of women, a weakening of marriage, and an increase in divorce with deleterious effects on children such as child poverty, poorer health, lower educational achievement, suicide risks, drug and alcohol abuse, criminality, and incarceration, among others. The environmental impact is discussed briefly and includes the feminization and trans-gendering of male fish downstream from the effluent of city wastewater treatment plants with declining fish populations. The potential economic impact of most of these side effects is estimated based on epidemiologic data and published estimates of costs of caring for the diseases which are linked to the use of hormonally active contraceptives. Hormonally active contraceptives appear to have a deleterious impact on multiple aspects of women's health as well as negative economic and environmental impacts. These risks can be avoided through the use of nonhormonal methods and need to be more clearly conveyed to the public.

SUMMARY

Hormonal contraceptives have wide-ranging effects.  The potential economic impact of the medical side effects is estimated. Sociological effects are discussed including abortion, exploitation of women, a weakening of marriage and an increase in divorce with negative effects on children such as child poverty, poorer health, lower educational achievement, suicide risks, drug and alcohol abuse, criminality and incarceration among others. The environmental impact includes hormonal effects on fish with declining fish populations. Women seeking birth control have a right to know about how to avoid these risks by using effective hormone-free methods like Fertility Awareness Methods.

The preventive effect of breastfeeding against ovarian cancer in BRCA1 and BRCA2 mutation carriers: A systematic review and meta-analysis

OBJECTIVE

A recent study showed that even a few months of breastfeeding is associated with a significant decrease in the risk of ovarian cancer in the general population. This study aimed to perform a systematic review and meta-analysis to determine the significance of the length of the breastfeeding period on ovarian cancer risk in BRCA1/2 mutation carriers.

METHODS

PubMed, EMBASE, and Cochrane databases were searched up to June 1, 2021. We included case-control and cohort studies that contained information on breastfeeding and the risk of ovarian cancer in BRCA1/2 mutation carriers. Odds ratios (OR) were meta-analytically pooled using a fixed-effects model.dd RESULTS: Five studies, including one cohort study and four case-control studies, were included in this meta-analysis. Of the 14,601 BRCA1/2 mutation carriers, the overall pooled OR of ever having performed breastfeeding in patients who had ovarian cancer was 0.767 (95% confidence interval [CI], 0.688-0.856) and 0.817 (95% CI, 0.650-1.028) for patients with BRCA1 and BRCA2 mutation, respectively. Breastfeeding for >1 year acted as a protective factor in both BRCA1 [OR: 0.787 (95% CI, 0.682-0.907)] and BRCA2 [OR: 0.567 (95% CI, 0.400-0.802)] mutation carriers. No significant heterogeneity was present (I2 = 0%), and the funnel plot was also properly distributed, showing no publication bias.

CONCLUSIONS

Breastfeeding is a preventive, modifiable factor for ovarian cancer in BRCA1/2 mutation carriers. Ever having performed breastfeeding was significantly preventive for ovarian cancer in the BRCA1 mutation carriers, however a period of 1 year or more of breastfeeding is required for a reduced ovarian cancer risk in BRCA2 mutation carriers.

Remodeling of the maternal gut microbiome during pregnancy is shaped by parity

BACKGROUND

The maternal microbiome has emerged as an important factor in gestational health and outcome and is associated with risk of preterm birth and offspring morbidity. Epidemiological evidence also points to successive pregnancies-referred to as maternal parity-as a risk factor for preterm birth, infant mortality, and impaired neonatal growth. Despite the fact that both the maternal microbiome and parity are linked to maternal-infant health, the impact of parity on the microbiome remains largely unexplored, in part due to the challenges of studying parity in humans.

RESULTS

Using synchronized pregnancies and dense longitudinal monitoring of the microbiome in pigs, we describe a microbiome trajectory during pregnancy and determine the extent to which parity modulates this trajectory. We show that the microbiome changes reproducibly during gestation and that this remodeling occurs more rapidly as parity increases. At the time of parturition, parity was linked to the relative abundance of several bacterial species, including Treponema bryantii, Lactobacillus amylovorus, and Lactobacillus reuteri. Strain tracking carried out in 18 maternal-offspring "quadrads"-each consisting of one mother sow and three piglets-linked maternal parity to altered levels of Akkermansia muciniphila, Prevotella stercorea, and Campylobacter coli in the infant gut 10 days after birth.

CONCLUSIONS

Collectively, these results identify parity as an important environmental factor that modulates the gut microbiome during pregnancy and highlight the utility of a swine model for investigating the microbiome in maternal-infant health. In addition, our data show that the impact of parity extends beyond the mother and is associated with alterations in the community of bacteria that colonize the offspring gut early in life. The bacterial species we identified as parity-associated in the mother and offspring have been shown to influence host metabolism in other systems, raising the possibility that such changes may influence host nutrient acquisition or utilization. These findings, taken together with our observation that even subtle differences in parity are associated with microbiome changes, underscore the importance of considering parity in the design and analysis of human microbiome studies during pregnancy and in infants. Video abstract.

Cardiac Tamponade Unmasking Recurrent Ovarian Cancer

Pericardial disease is a common manifestation of malignancy. Gynecologic malignancies such as ovarian cancer rarely present with cardiac involvement. Cardiac tamponade may be the initial presentation of malignancy in as many as half of pericardial disease cases. We report the case of a 60-year-old female with known ovarian adenocarcinoma, who achieved initial success with tumor debulking and adjuvant chemotherapy but was lost to follow-up. She presented again three years later with new-onset dyspnea and described a syncopal episode. A chest radiograph showed an enlarged cardiac silhouette and bilateral pleural effusions. Transthoracic echocardiography revealed a large pericardial effusion with diastolic collapse of the right atrium and ventricle, consistent with tamponade physiology. Subxiphoid pericardiocentesis and pigtail drain were placed under fluoroscopy with resolution of symptoms and no recurrence. Neoplastic etiology was confirmed by immunocytochemistry on cell block positive for PAX-8. As an adjunct or alternative to cytologic evaluation, diffusion-weighted magnetic resonance imaging and calculation of the apparent diffusion coefficient can be used to differentiate between malignant and benign effusions. Malignant pericardial effusion in ovarian cancer is a treatable oncologic emergency where timely diagnosis and management may facilitate palliation and prolong life.

Worldwide incidence and mortality of ovarian cancer and Human Development Index (HDI): GLOBOCAN sources and methods 2018

Objective

Ovarian cancer is known as the seventh most common cancer among women, accounting for about 4% of all cancers associated with the females.

Method

This is a descriptive cross-sectional study based on cancer incidence data and cancer mortality rates from the Global Cancer Data in 2018. The incidence and mortality rates were estimated and ovarian cancer distribution maps for world countries were drawn. To analyze data, correlation and regression tests were used to evaluate association between its incidence and mortality with human development index (HDI)

Results

Results revealed a direct and significant correlation between ovarian cancer incidence (R = 0.409, P < 0.0001) and mortality (R = 0.193, P < 0.05) with HDI. It also projected a direct and significant correlation between incidence with Gross National Income per 1,000 capita (GNI), mean years of schooling (MYS), life expectancy at birth (LEB) and expected years of schooling (EYS) (P < 0.0001). The findings also demonstrated a direct and significant correlation between mortality and GNI, MYS, LEB as well as EYS (P < 0.05). The linear regression model showed that a higher MYS [B = 0.2, CI 95%: (-0.03, 0.5)] can significantly augment the incidence of ovarian cancer while an increased MYS [B = 0.2, CI 95% (0.03, 0.4)] can induce mortality.

Conclusions

Given the direct and significant correlation between ovarian cancer incidence and mortality with HDI, attention to risk factors in these countries can be effective in curbing its incidence and mortality.

Endogenous sex steroid hormones and colorectal cancer risk: a systematic review and meta-analysis

Preclinical data suggest that endogenous sex steroid hormones may be implicated in colorectal cancer (CRC) development, however, findings from epidemiological studies are conflicting. The aim of this systematic review and meta-analysis was to investigate the associations between endogenous concentrations of sex hormones and CRC risk. PubMed and Scopus were searched until June 2020 for prospective studies evaluating the association between pre-diagnostic plasma/serum concentrations of estradiol, testosterone and sex-hormone binding globulin (SHBG) and CRC risk. Summary relative risks (RRs) and 95% confidence intervals (CIs) were estimated using the inverse-variance weighted random-effects model based on the DerSimonian-Laird estimator. Eight studies were included in the meta-analysis after evaluating 3,859 non-duplicate records. Four of the eight studies had a nested case-control design, one study was a case-cohort and the rest three studies were cohort studies, and they included on average 295 cases (range:48-732) and 2,105 controls. No associations were found for endogenous sex steroid hormones in men or post-menopausal women with CRC risk, with evidence for substantial heterogeneity observed among women. Findings from this meta-analysis do not support presence of associations between pre-diagnostic concentrations of testosterone, estradiol and SHBG with incident CRC risk in men and post-menopausal women.

Expanding Our Understanding of Ovarian Cancer Risk: The Role of Incomplete Pregnancies

BACKGROUND

Parity is associated with decreased risk of invasive ovarian cancer; however, the relationship between incomplete pregnancies and invasive ovarian cancer risk is unclear. This relationship was examined using 15 case-control studies from the Ovarian Cancer Association Consortium (OCAC). Histotype-specific associations, which have not been examined previously with large sample sizes, were also evaluated.

METHODS

A pooled analysis of 10 470 invasive epithelial ovarian cancer cases and 16 942 controls was conducted. Odds ratios (ORs) and 95% confidence intervals (CIs) for the association between incomplete pregnancies and invasive epithelial ovarian cancer were estimated using logistic regression. All models were conditioned on OCAC study, race and ethnicity, age, and education level and adjusted for number of complete pregnancies, oral contraceptive use, and history of breastfeeding. The same approach was used for histotype-specific analyses.

RESULTS

Ever having an incomplete pregnancy was associated with a 16% reduction in ovarian cancer risk (OR = 0.84, 95% CI = 0.79 to 0.89). There was a trend of decreasing risk with increasing number of incomplete pregnancies (2-sided Ptrend < .001). An inverse association was observed for all major histotypes; it was strongest for clear cell ovarian cancer.

CONCLUSIONS

Incomplete pregnancies are associated with a reduced risk of invasive epithelial ovarian cancer. Pregnancy, including incomplete pregnancy, was associated with a greater reduction in risk of clear cell ovarian cancer, but the result was broadly consistent across histotypes. Future work should focus on understanding the mechanisms underlying this reduced risk.

Age of Natural Menopause Among Jordanian Women and Factors Related to Premature and Early Menopause

OBJECTIVE

The aim of this study was to assess factors related to the onset of premature/early natural menopause among Jordanian women.

METHODS

A cross-sectional study was conducted in early 2016. Subjects were enrolled based on random drop-off technique to the Obstetrics and Gynecology clinics at the Jordan University Hospital. Women 18 years of age and above were initially eligible to enroll, and women who had surgically induced menopause or specific disease were excluded from the analysis. Relevant data were collected using a questionnaire that included 30 questions. The following variables were collected: socio-demographic, body mass index, chronic conditions, diseases, reproductive characteristics, and health status. Hormone indicators of menopause were tested by measuring estrogen (E2) and follicle-stimulating hormone (FSH) levels. Age at natural menopause (ANM) was self-reported retrospectively and considered an independent variable against BMI, smoking, hormone therapy, and concomitant diseases. Association analysis and multinomial logistic regression were used to examine the associated factors of ANM with adjusted odds ratios (ORs), and their 95% confidence intervals (CIs) were reported.

RESULTS

A total of 409 women were included in the analysis, aged between 20-75 years. The mean ANM in our sample was 48.5±5.0, with 2.7% of the women experienced premature menopause (ANM <40) and 7.8% early menopause (ANM 40-44). Within the menopause women (n=242), the percentage of women who had premature menopause was 4.5%, 13.6% with early menopause, and 21.1% with late menopause (ANM >52). Smoking was the major risk factor for premature/early menopausal age among Jordanian women with an OR of 2.46 (95% CI: 1.08-5.59, p<0.05). On the other hand, women with occasional arthritis symptoms and diseases such as hypertension, diabetes, dyslipidemia, and their combination were associated with average (45-52 years) or late menopause (>52 years).

CONCLUSION

Smoking is the main contributor of premature/early menopause in Jordanian women. Increased awareness and public health policy about the adverse effects of smoking on women's reproductive health are needed.

Targeting progesterone signaling prevents metastatic ovarian cancer

Effective cancer prevention requires the discovery and intervention of a factor critical to cancer development. Here we show that ovarian progesterone is a crucial endogenous factor inducing the development of primary tumors progressing to metastatic ovarian cancer in a mouse model of high-grade serous carcinoma (HGSC), the most common and deadliest ovarian cancer type. Blocking progesterone signaling by the pharmacologic inhibitor mifepristone or by genetic deletion of the progesterone receptor (PR) effectively suppressed HGSC development and its peritoneal metastases. Strikingly, mifepristone treatment profoundly improved mouse survival (∼18 human years). Hence, targeting progesterone/PR signaling could offer an effective chemopreventive strategy, particularly in high-risk populations of women carrying a deleterious mutation in the BRCA gene.

Influence of breast cancer risk factors and intramammary biotransformation on estrogen homeostasis in the human breast

Understanding intramammary estrogen homeostasis constitutes the basis of understanding the role of lifestyle factors in breast cancer etiology. Thus, the aim of the present study was to identify variables influencing levels of the estrogens present in normal breast glandular and adipose tissues (GLT and ADT, i.e., 17β-estradiol, estrone, estrone-3-sulfate, and 2-methoxy-estrone) by multiple linear regression models. Explanatory variables (exVARs) considered were (a) levels of metabolic precursors as well as levels of transcripts encoding proteins involved in estrogen (biotrans)formation, (b) data on breast cancer risk factors (i.e., body mass index, BMI, intake of estrogen-active drugs, and smoking) collected by questionnaire, and (c) tissue characteristics (i.e., mass percentage of oil, oil%, and lobule type of the GLT). Levels of estrogens in GLT and ADT were influenced by both extramammary production (menopausal status, intake of estrogen-active drugs, and BMI) thus showing that variables known to affect levels of circulating estrogens influence estrogen levels in breast tissues as well for the first time. Moreover, intratissue (biotrans)formation (by aromatase, hydroxysteroid-17beta-dehydrogenase 2, and beta-glucuronidase) influenced intratissue estrogen levels, as well. Distinct differences were observed between the exVARs exhibiting significant influence on (a) levels of specific estrogens and (b) the same dependent variables in GLT and ADT. Since oil% and lobule type of GLT influenced levels of some estrogens, these variables may be included in tissue characterization to prevent sample bias. In conclusion, evidence for the intracrine activity of the human breast supports biotransformation-based strategies for breast cancer prevention. The susceptibility of estrogen homeostasis to systemic and tissue-specific modulation renders both beneficial and adverse effects of further variables associated with lifestyle and the environment possible.

Association Between Breastfeeding and Ovarian Cancer Risk

Importance

Breastfeeding has been associated with a reduced risk of epithelial ovarian cancer in multiple studies, but others showed no association. Whether risk reduction extends beyond that provided by pregnancy alone or differs by histotype is unclear. Furthermore, the observed associations between duration and timing of breastfeeding with ovarian cancer risk have been inconsistent.

Objective

To determine the association between breastfeeding (ie, ever/never, duration, timing) and ovarian cancer risk overall and by histotype.

Design, Setting, and Participants

A pooled analysis of parous women with ovarian cancer and controls from 13 case-control studies participating in the Ovarian Cancer Association Consortium was performed. Odds ratios (ORs) and 95% CIs of the overall association were calculated using multivariable logistic regression and polytomous logistic regression for histotype-specific associations. All data were collected from individual sites from November 1989 to December 2009, and analysis took place from September 2017 to July 2019.

Exposures

Data on breastfeeding history, including duration per child breastfed, age at first and last breastfeeding, and years since last breastfeeding were collected by questionnaire or interview and was harmonized across studies.

Main Outcomes and Measures

Diagnosis of epithelial ovarian cancer.

Results

A total of 9973 women with ovarian cancer (mean [SD] age, 57.4 [11.1] years) and 13 843 controls (mean [SD] age, 56.4 [11.7] years) were included. Breastfeeding was associated with a 24% lower risk of invasive ovarian cancer (odds ratio [OR], 0.76; 95% CI, 0.71-0.80). Independent of parity, ever having breastfed was associated with reduction in risk of all invasive ovarian cancers, particularly high-grade serous and endometrioid cancers. For a single breastfeeding episode, mean breastfeeding duration of 1 to 3 months was associated with 18% lower risk (OR, 0.82; 95% CI, 0.76-0.88), and breastfeeding for 12 or more months was associated with a 34% lower risk (OR, 0.66; 95% CI, 0.58-0.75). More recent breastfeeding was associated with a reduction in risk (OR, 0.56; 95% CI, 0.47-0.66 for <10 years) that persisted for decades (OR, 0.83; 95% CI, 0.77-0.90 for ≥30 years; P for trend = .02).

Conclusions and Relevance

Breastfeeding is associated with a significant decrease in risk of ovarian cancer overall and for the high-grade serous subtype, the most lethal type of ovarian cancer. The findings suggest that breastfeeding is a potentially modifiable factor that may lower risk of ovarian cancer independent of pregnancy alone.

An Overview of Candidate Therapeutic Target Genes in Ovarian Cancer

Ovarian cancer (OC) shows the highest mortality rate among gynecological malignancies and, because of the absence of specific symptoms, it is frequently diagnosed at an advanced stage, mainly due to the lack of specific and early biomarkers, such as those based on cancer molecular signature identification. Indeed, although significant progress has been made toward improving the clinical outcome of other cancers, rates of mortality for OC are essentially unchanged since 1980, suggesting the need of new approaches to identify and characterize the molecular mechanisms underlying pathogenesis and progression of these malignancies. In addition, due to the low response rate and the high frequency of resistance to current treatments, emerging therapeutic strategies against OC focus on targeting single factors and pathways specifically involved in tumor growth and metastasis. To date, loss-of-function screenings are extensively applied to identify key drug targets in cancer, seeking for more effective, disease-tailored treatments to overcome lack of response or resistance to current therapies. We review here the information relative to essential genes and functional pathways recently discovered in OC, often strictly interconnected with each other and representing promising biomarkers and molecular targets to treat these malignancies.

Vitamin D Exposure and Ovarian Cancer Risk and Prognosis

Given the poor prognosis of ovarian cancer and limited population-level strategies for early detection and long-term treatment success, knowledge of modifiable risk factors for prevention and improved prognosis is important. Vitamin D has received wide scientific interest in cancer research as having the potential to be one such factor. We carried out a systematic narrative review of the literature on vitamin D and ovarian cancer risk and survival. We included 17 case-control and cohort studies on ovarian cancer incidence. Five analyses were of sun exposure, among which three reported an inverse association. Of 11 analyses of dietary vitamin D, two reported an inverse association. Among five studies of 25(OH)D levels, an inverse association was reported in two. Across all studies the findings were inconsistent, but some recent studies have suggested that vitamin D exposure at earlier ages may be important. Only three studies examining vitamin D exposure in relation to survival among ovarian cancer survivors were identified and the findings were inconsistent. The evidence to date supports a null influence of vitamin D on both ovarian cancer risk and survival. Future research should ensure that exposure assessment captures vitamin D exposure from all sources and for the etiologically or prognostically pertinent period.

Patterns of ovarian cancer and uterine cancer mortality and incidence in the contiguous USA

The main objective is to investigate the geographical variation in ovarian cancer and uterine cancer mortality, and to test associations between some risk factors and these cancer types in the contiguous US for mortality and for incidence. The modern disease surveillance software SaTScan™ was used for a spatial cluster analysis to assess any observable geographical variation in ovarian and uterine cancer mortality rates and to identify and test for spatial clusters with elevated relative risk. The analyses were first completed using age adjusted cancer rates for ovarian cancer and for uterine cancer. The cancer data was then adjusted for the risk factors (or covariates) obesity rate, smoking rate, urban, poverty rate, college education rate, race, opioids mortality rate, and for arsenic intake from well water rate. All used data for cancer mortality were for 2000-2014 while incidence data were for 2011-2015. There exist seven significant mortality clusters of ovarian cancer, with large clusters in NW, NE and SE of the US, and there exist two large mortality clusters of uterine cancer in NE and Central US. Most risk factors studied for mortality and for incidence were significant at significance levels much lower than 0.05 for either of the two cancer types, except race for ovarian cancer mortality and arsenic for ovarian incidence. This study has identified several important factors, and these findings could be used for a more effective search for cancer prevention for uterine and ovarian cancer. LIMITATIONS OF THE STUDY: The accuracy of the data could not be controlled as data were downloaded from websites. While the mortality data was complete, the incidence data had counties with missing data. The data were obtained at the county resolution. No data were available on women who had one type of cancer and then had the second type of cancer later in life. Only purely spatial clusters were studied and no temporal analysis was done.

Assisted reproductive technology treatment and risk of ovarian cancer—a nationwide population-based cohort study

STUDY QUESTION

Does hormone stimulation during assisted reproductive technology (ART) treatment increase the risk of ovarian cancer?

SUMMARY ANSWER

No increased risk of ovarian cancer was found among ART-treated women, with the exception of ART-treated women with endometriosis.

WHAT IS KNOWN ALREADY

Previous studies on the association between ovarian stimulation during ART and ovarian cancer have shown conflicting results. The risk of ovarian cancer varies according to the cause of infertility, and only a few studies on ART treatment and risk of ovarian cancer have had sufficient data to address this issue. Endometriosis has been linked to an increased risk of ovarian cancer.

STUDY DESIGN, SIZE, DURATION

Women undergoing ART treatment during 1994–2015 were registered in the Danish IVF register. Data were linked with data from the Danish Cancer Register and socio-demographic population registers using an individual person identification number assigned to people residing in Denmark.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All women undergoing ART treatment were age-matched with a random sample of the female background population and followed for up to 22 years. After relevant exclusions, the population consisted of 58 472 ART-treated women and 625 330 untreated women, all with no previous malignancies. Ovarian cancer risk was assessed using multivariable cox regression analyses with adjustment for educational level, marital status, parity and treatment year. Results are shown as hazard ratios (HRs) with corresponding CIs.

MAIN RESULTS AND THE ROLE OF CHANCE

In total, 393 (0.06%) women were diagnosed with ovarian cancer during follow-up (mean 9.7 years). Women treated with ART had an increased risk of ovarian cancer (HR 1.20, 95% CI 1.10–1.31), which diminished over time. The increased risk was apparent among women with female factor infertility (HR 1.36, 95% CI 1.25–1.48), whereas no female factor infertility was associated with a lower risk (HR 0.87, 95% CI 0.76–1.00). The risk was increased among women with endometriosis (HR 3.78, 95% CI 2.45–5.84), whereas no increased risk was found among ART-treated women with polycystic ovary syndrome, other female causes of infertility and unexplained infertility.

LIMITATIONS, REASONS FOR CAUTION

The association between ART treatment and ovarian cancer is likely influenced by increased detection due to multiple ultrasound scans during ART treatment.

WIDER IMPLICATIONS OF THE FINDINGS

Undergoing ART treatment without the presence of endometriosis was not associated with an increased risk of ovarian cancer, which is reassuring. Whether ART treatment increases the risk of ovarian cancer among women with endometriosis needs further investigation.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a PhD grant to D.V. from the Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. Funding for establishing the Danish National ART-couple II cohort was achieved from Ebba Rosa Hansen Foundation. The funders had no influence on data collection, analyses or results presented. The authors have no conflicts of interest to declare.

Qualitative and quantitative differences in estrogen biotransformation in human breast glandular and adipose tissues: implications for studies using mammary biospecimens

Because of its assumed role in breast cancer etiology, estrogen biotransformation (and interaction of compounds therewith) has been investigated in human biospecimens for decades. However, little attention has been paid to the well-known fact that large inter-individual variations exist in the proportion of breast glandular (GLT) and adipose (ADT) tissues and less to adequate tissue characterization. To assess the relevance of this, the present study compares estrogen biotransformation in GLT and ADT. GLT and ADT were isolated from 47 reduction mammoplasty specimens derived from women without breast cancer and were characterized histologically and by their percentages of oil. Levels of 12 unconjugated and five conjugated estrogens were analyzed by GC- and UHPLC-MS/MS, respectively, and levels of 27 transcripts encoding proteins involved in estrogen biotransformation by Taqman^® probe-based PCR. Unexpectedly, one-third of specimens provided neat GLT only after cryosection. Whereas 17β-estradiol, estrone, and estrone-3-sulfate were detected in both tissues, estrone-3-glucuronide and 2-methoxy-estrone were detected predominately in GLT and ADT, respectively. Estrogen levels as well as ratios 17β-estradiol/estrone and estrone-3-sulfate/estrone differed significantly between GLT and ADT, yet less than between individuals. Furthermore, estrogen levels in GLT and ADT correlated significantly with each other. In contrast, levels of most transcripts encoding enzymes involved in biotransformation differed more than between individuals and did not correlate between ADT and GLT. Thus, mixed breast tissues (and plasma) will not provide meaningful information on local estrogen biotransformation (and interaction of compounds therewith) whereas relative changes in 17β-estradiol levels may be investigated in the more abundant ADT.

Appraising the role of previously reported risk factors in epithelial ovarian cancer risk: A Mendelian randomization analysis

BACKGROUND

Various risk factors have been associated with epithelial ovarian cancer risk in observational epidemiological studies. However, the causal nature of the risk factors reported, and thus their suitability as effective intervention targets, is unclear given the susceptibility of conventional observational designs to residual confounding and reverse causation. Mendelian randomization (MR) uses genetic variants as proxies for risk factors to strengthen causal inference in observational studies. We used MR to evaluate the association of 12 previously reported risk factors (reproductive, anthropometric, clinical, lifestyle, and molecular factors) with risk of invasive epithelial ovarian cancer, invasive epithelial ovarian cancer histotypes, and low malignant potential tumours.

METHODS AND FINDINGS

Genetic instruments to proxy 12 risk factors were constructed by identifying single nucleotide polymorphisms (SNPs) that were robustly (P < 5 × 10-8) and independently associated with each respective risk factor in previously reported genome-wide association studies. These risk factors included genetic liability to 3 factors (endometriosis, polycystic ovary syndrome, type 2 diabetes) scaled to reflect a 50% higher odds liability to disease. We obtained summary statistics for the association of these SNPs with risk of overall and histotype-specific invasive epithelial ovarian cancer (22,406 cases; 40,941 controls) and low malignant potential tumours (3,103 cases; 40,941 controls) from the Ovarian Cancer Association Consortium (OCAC). The OCAC dataset comprises 63 genotyping project/case-control sets with participants of European ancestry recruited from 14 countries (US, Australia, Belarus, Germany, Belgium, Denmark, Finland, Norway, Canada, Poland, UK, Spain, Netherlands, and Sweden). SNPs were combined into multi-allelic inverse-variance-weighted fixed or random effects models to generate effect estimates and 95% confidence intervals (CIs). Three complementary sensitivity analyses were performed to examine violations of MR assumptions: MR-Egger regression and weighted median and mode estimators. A Bonferroni-corrected P value threshold was used to establish strong evidence (P < 0.0042) and suggestive evidence (0.0042 < P < 0.05) for associations. In MR analyses, there was strong or suggestive evidence that 2 of the 12 risk factors were associated with invasive epithelial ovarian cancer and 8 of the 12 were associated with 1 or more invasive epithelial ovarian cancer histotypes. There was strong evidence that genetic liability to endometriosis was associated with an increased risk of invasive epithelial ovarian cancer (odds ratio [OR] per 50% higher odds liability: 1.10, 95% CI 1.06-1.15; P = 6.94 × 10-7) and suggestive evidence that lifetime smoking exposure was associated with an increased risk of invasive epithelial ovarian cancer (OR per unit increase in smoking score: 1.36, 95% CI 1.04-1.78; P = 0.02). In analyses examining histotypes and low malignant potential tumours, the strongest associations found were between height and clear cell carcinoma (OR per SD increase: 1.36, 95% CI 1.15-1.61; P = 0.0003); age at natural menopause and endometrioid carcinoma (OR per year later onset: 1.09, 95% CI 1.02-1.16; P = 0.007); and genetic liability to polycystic ovary syndrome and endometrioid carcinoma (OR per 50% higher odds liability: 0.89, 95% CI 0.82-0.96; P = 0.002). There was little evidence for an association of genetic liability to type 2 diabetes, parity, or circulating levels of 25-hydroxyvitamin D and sex hormone binding globulin with ovarian cancer or its subtypes. The primary limitations of this analysis include the modest statistical power for analyses of risk factors in relation to some less common ovarian cancer histotypes (low grade serous, mucinous, and clear cell carcinomas), the inability to directly examine the association of some ovarian cancer risk factors that did not have robust genetic variants available to serve as proxies (e.g., oral contraceptive use, hormone replacement therapy), and the assumption of linear relationships between risk factors and ovarian cancer risk.

CONCLUSIONS

Our comprehensive examination of possible aetiological drivers of ovarian carcinogenesis using germline genetic variants to proxy risk factors supports a role for few of these factors in invasive epithelial ovarian cancer overall and suggests distinct aetiologies across histotypes. The identification of novel risk factors remains an important priority for the prevention of epithelial ovarian cancer.

No. 329-Canadian Contraception Consensus Part 4 of 4 Chapter 9: Combined Hormonal Contraception

OBJECTIVE

To provide guidelines for health care providers on the use of contraceptive methods to prevent pregnancy and on the promotion of healthy sexuality.

OUTCOMES

Overall efficacy of cited contraceptive methods, assessing reduction in pregnancy rate, safety, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the availability of cited contraceptive methods in Canada.

EVIDENCE

Medline and the Cochrane Database were searched for articles in English on subjects related to contraception, sexuality, and sexual health from January 1994 to December 2015 in order to update the Canadian Contraception Consensus published February-April 2004. Relevant Canadian government publications and position papers from appropriate health and family planning organizations were also reviewed.

VALUES

The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice are ranked according to the method described in this report.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Incidence of intraepithelial fallopian tube neoplasias in mexican women over 40 years of age that underwent elective hysterectomy

AIMS

The incidence of intraepithelial neoplasia in the fallopian tubes of women over 40 years of age who had undergone elective hysterectomy was assessed at the Aguascalientes Women's Hospital.

METHODS

An observational, prospective, descriptive study was carried out at the Aguascalientes Women's Hospital on female patients over 40 years of age who underwent elective hysterectomy between July and October 2017. In these 4 months, 85 patients underwent elective hysterectomy.

RESULTS

In this study, 85 patients who received a hysterectomy for non-oncological reasons were analyzed. Salpinx alterations compatible with intraepithelial neoplasia in the Fallopian tubes were found in 2.4% of the patients studied.

CONCLUSIONS

The incidence of intraepithelial neoplasia in the fallopian tubes of high-risk patients at the Aguascalientes Women's Hospital is 2.4%. Prophylactic salpingectomy is a simple procedure and has the potential to decrease the risk of high-grade ovarian cancer. In premenopausal patients, total abdominal hysterectomy with bilateral salpingectomy should be the procedure most often performed.

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.

Association of Combined Estrogen-Progestogen and Progestogen-Only Contraceptives with the Development of Cancer

Combined estrogen-progestogen contraceptives (oral contraceptives or OCs) and progestogen-only contraceptives (POCs) are synthetic steroids that bind to steroid hormone receptors, which are widespread throughout the body. They have a profound effect on cellular physiology. Combined OCs have been classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogens, but their findings have not been updated recently. In order to update the information and better understand the impact that OCs and POCs have on the risk of development of cancers, a comprehensive literature search was undertaken, focusing on more recently published papers. In agreement with the IARC, the recent literature confirms an increased risk of breast cancer and cervical cancer with the use of OCs. The recent literature also confirms the IARC conclusion that OCs decrease the risk of ovarian and endometrial cancers. However, there is little support from recent studies for the IARC conclusion that OCs decrease the risk of colorectal cancer or increase the risk of liver cancer. For liver cancer, this may be due to the recent studies having been performed in areas where hepatitis is endemic. In one large observational study, POCs also appear to increase the overall risk of developing cancer. OCs and POCs appear to increase the overall risk of cancer when carefully performed studies with the least intrinsic bias are considered.

Summary

OCs have been classified as cancer-causing agents, especially leading to increases in breast cancer and cervical cancer. A review of the recent scientific literature was performed to see whether this still appears to be the case. The recent literature supports the cancer-causing role of OCs especially for breast cancer and cervical cancer. Studies also indicate that progesterone-only contraceptives (such as implants and vaginal rings) also can cause cancer. This is especially true for breast cancer and cervical cancer.

Diet and risk of breast, endometrial and ovarian cancer: UK Women's Cohort Study

This study aimed to investigate the association between diet and the risk of breast, endometrial and ovarian cancer in the UK Women's Cohort Study. A total of 35 372 women aged 35-69 years were enrolled between 1995 and 1998 and completed a validated 217-item FFQ. The individual foods were collapsed into sixty-four main food groups and compared using Cox proportional models, adjusting for potential confounders. Hazard ratio (HR) estimates are presented per portion increase in food items. After approximately 18 years of follow-up, there were 1822, 294 and 285 cases of breast, endometrial and ovarian cancer, respectively. A high consumption of processed meat and total meat was associated with an increased risk of breast and endometrial cancer. High intake of tomatoes (HR 0·87, 99 % CI 0·75, 1·00) and dried fruits (HR 0·60, 99 % CI 0·37, 0·97) was associated with a reduced risk of breast and endometrial cancer, respectively. Mushroom intake was associated with a higher risk of ovarian cancer (HR 1·57, 99 % CI 1·09, 2·26). Subgroup analysis by pre- or postmenopausal cancer further demonstrated an association between processed meat intake and both postmenopausal breast cancer and endometrial cancer. Intake of dried fruits was associated with a reduced risk of postmenopausal endometrial cancer (HR 0·55, 99 % CI 0·31, 0·98). Our findings suggest that while some foods may trigger the risk of these cancers, some foods may also be protective; supporting the call for further randomised controlled trials of dietary interventions to reduce the risk of cancer among pre- and postmenopausal women.

An Overview on the Anticancer Activity of Azadirachta indica (Neem) in Gynecological Cancers

In recent years, a wide range of studies have pointed out the importance of nutraceuticals as reservoirs of therapeutic compounds for several diseases, including cancer. This study is centered on the role of some nutraceuticals as anticancer agents and on their efficiency in the oncological gynecological field. Gynecological cancers include cervical, ovarian, and breast neoplasia and these are the major causes of morbidity and mortality in the female population. Cervical neoplasia affects sexually active women aged between 30 and 40 years and is considered the second leading cause of death for women worldwide. Epidemiological studies have shown a strong association of this cancer with human papilloma virus (HPV) infection, independent of any others risk factors. Ovarian cancer represents about 4% of all women’s cancers and breast neoplasia registers 52.8 new cases per 100,000 women annually. Since ancient times, herbal therapies have shown a wide range of beneficial effects and a high potential for safeguarding human health. Azadirachta indica (Neem) is a medicinal plant of Indian origin, a tree with more of 140 isolated compounds and at least 35 biologically active principles that have shown an important influence as tumor suppressors by interfering with the carcinogenesis process. Used for centuries in Asia as a natural remedy for cancer, neem compounds present in bark, leaves, flowers, and seed oil have been shown to possess properties such as chemopreventive capacity, apoptotic activities, immunomodulatory effects, and induction of p53-independent apoptosis. The current study is a systematic literature review based on the anticarcinogenic potential of neem compounds in gynecological cancers.

Hormone Levels in Pregnancy and Subsequent Risk of Maternal Breast and Ovarian Cancer: A Systematic Review

OBJECTIVE

Some maternal hormone levels in pregnancy are associated with a higher risk of breast and ovarian cancer. This study systematically assessed the association between blood hormone levels measured in pregnancy and future risk of these cancers.

METHODS

Two reviewers independently conducted a literature search of MEDLINE and EMBASE databases from January 1970 to August 2017. Studies were included that measured one or more serum hormone levels in pregnancy and later assessed for cancer. Cancer outcomes were considered by cancer type, each in relation to a specific maternal hormone.

RESULTS

Eleven studies were included, comprising a total of 57 967 women. The interval between pregnancy and cancer onset varied from 4.1 to 20.5 years. Elevated serum chorionic gonadotropin (two of four studies) and alpha fetoprotein (two of three studies) were each associated with a lower risk of maternal breast cancer, whereas elevated estrone levels suggested a higher risk (one of three studies). Elevated testosterone (one of one study) and androstenedione (one of one study) were each associated with a significantly greater risk of sex-cord stromal ovarian tumours. Higher serum 17-hydroxyprogesterone was associated with an increased risk of sex-cord stromal (one of one study) and epithelial (one of one study) ovarian cancer.

CONCLUSION

Observational studies suggest some degree of association between serum hormones measured in pregnancy and a woman's future risk of breast and ovarian cancer. More data are needed to determine sufficiently whether certain blood hormone levels measured in pregnancy are predictive of future cancer risk.

VEGFR2 Expression Is Differently Modulated by Parity and Nulliparity in Mouse Ovary

Parity and nulliparity exert opposite effects on women's health, as parity is considered a protective factor for several reproductive diseases. This study is aimed at determining if ovarian VEGF and VEGFR2 expression are differently modulated in the ovaries of parous and nulliparous mice. To this end primiparous and nulliparous fertile mice were sacrificed at postovulatory stage. Whole ovaries, corpus luteum, and residual stromal tissues were analyzed to assess VEGF/VEGFR2 expression levels. Ovarian mRNA amounts of Vegfa (120 and 164) and Vegfr2 were comparable between primiparous and nulliparous mice; both isoforms and receptor were accumulated mainly in corpus luteum tissues. VEGF 120 and 164 protein accumulation and distribution mirrored that of mRNA. Conversely, VEGFR2 protein content was significantly higher in ovaries of nulliparous mice and was more efficiently phosphorylated in ovaries of primiparous mice. In both groups, VEGFR2 was preferentially expressed in corpus luteum, while its phosphorylated form was equally distributed in two somatic compartments. We suggest that parity influences VEGFR2/phospho-VEGFR2 expression and tissue distribution. This difference could be part of a more complex mechanism that at least in mice is activated after the first pregnancy and likely aims to preserve female health.

Association between contemporary hormonal contraception and ovarian cancer in women of reproductive age in Denmark: prospective, nationwide cohort study

OBJECTIVES

To investigate the association between contemporary combined hormonal contraceptives (including progestogen types in combined preparations and all progestogen-only products) and overall and specific types of ovarian cancer.

DESIGN

Prospective, nationwide cohort study.

SETTING

Denmark, 1995-2014.

PARTICIPANTS

All women aged 15-49 years during 1995-2014 were eligible. Women were excluded if they immigrated after 1995, had cancer (except non-melanoma skin cancer), had venous thrombosis, or were treated for infertility before entry (final study population included 1 879 227 women). Women were categorised as never users (no record of being dispensed hormonal contraception), current or recent users (≤1 year after stopping use), or former users (>1 year after stopping use) of different hormonal contraceptives.

MAIN OUTCOME MEASURES

Poisson regression was used to calculate relative risk of ovarian cancer among users of any contemporary combined hormonal contraceptives and by progestogen type in combined preparations and all progestogen-only products, including non-oral preparations. Separate analyses examined women followed up to their first contraception type switch and those with full contraceptive histories. Duration, time since last use, and tumour histology were examined and the population prevented fraction were calculated.

RESULTS

During 21.4 million person years, 1249 incident ovarian cancers occurred. Among ever users of hormonal contraception, 478 ovarian cancers were recorded over 13 344 531 person years. Never users had 771 ovarian cancers during 8 150 250 person years. Compared with never users, reduced risks of ovarian cancer occurred with current or recent use and former use of any hormonal contraception (relative risk 0.58 (95% confidence interval 0.49 to 0.68) and 0.77 (0.66 to 0.91), respectively). Relative risks among current or recent users decreased with increasing duration (from 0.82 (0.59 to 1.12) with ≤1 year use to 0.26 (0.16 to 0.43) with >10 years' use; P<0.001 for trend). Similar results were achieved among women followed up to their first switch in contraceptive type. Little evidence of major differences in risk estimates by tumour type or progestogen content of combined oral contraceptives was seen. Use of progestogen-only products were not associated with ovarian cancer risk. Among ever users of hormonal contraception, the reduction in the age standardised absolute rate of ovarian cancer was 3.2 per 100 000 person years. Based on the relative risk for the never use versus ever use categories of hormonal contraception (0.66), the population prevented fraction was estimated to be 21%-that is, use of hormonal contraception prevented 21% of ovarian cancers in the study population.

CONCLUSIONS

Use of contemporary combined hormonal contraceptives is associated with a reduction in ovarian cancer risk in women of reproductive age-an effect related to duration of use, which diminishes after stopping use. These data suggest no protective effect from progestogen-only products.

Personal, reproductive, and familial characteristics associated with bilateral oophorectomy in premenopausal women: A population-based case-control study

OBJECTIVES

We investigated the association of personal, reproductive, and familial characteristics with bilateral oophorectomy performed for nonmalignant indications in a US population.

STUDY DESIGN

In an established cohort study, we used the records-linkage system of the Rochester Epidemiology Project (REP http://www.rochesterproject.org) to identify 1653 premenopausal women who underwent bilateral oophorectomy in Olmsted County, Minnesota between 1988 and 2007 for a nonmalignant indication. Each woman was matched by age (±1 year) to a population-based referent woman who had not undergone bilateral oophorectomy as of the index date. We used case-control analyses to investigate several characteristics associated with bilateral oophorectomy. Odds ratios and their 95% confidence intervals were adjusted for race, education, and income.

RESULTS

In the overall analyses, infertility was more common in women who underwent bilateral oophorectomy than in the controls, whereas use of oral contraceptives, a history of breast feeding, and fibrocystic breast disease were less common. The women who underwent bilateral oophorectomy weighed more than controls, had a higher body mass index and were younger at menarche. The associations were more pronounced for women who underwent the bilateral oophorectomy before age 46 years, and some associations were different for women with or without a benign ovarian indication. Reported family histories of uterine and other cancers were more common in women without a benign ovarian indication.

CONCLUSIONS

We identified a number of personal, reproductive, and familial characteristics that were associated with bilateral oophorectomy over a 20-year period. Our historical findings may help inform decision-making about oophorectomy in the future.

Case for a role of the microbiome in gynecologic cancers: Clinician's perspective

In this review, we aimed to provide insight into the microbiome and its association with endometrial and ovarian cancer and their risk factors. We reviewed the literature focusing on the relationship between the microbiome and cancer, as well as the relationship between gynecologic diseases and cancers. The human body contains different kinds of microorganisms in various body parts, which is termed the microbiome. The number of microorganisms that live in and on the human body is greater than that of the human germ and somatic cells by 10-fold. The relationship between a human and their microbiome is complex; it is also one of the most important components of homeostasis. Impairment of microbiome-host homeostasis has been associated with obesity, several cancers, preterm labor, inflammatory and allergic conditions and neurodevelopmental disorders. Direct and strong causal relationships have been established for several cancers and microorganisms, such as gastric lymphoma and Helicobacter pylori infection. Interestingly, eradication of the infectious agents has also been shown to be therapeutic. The association between cancer and the microbiome, however, is more complicated than a 1 bacteria-1 cancer model, and a shift in a healthy microbiome can result in various cancers via inflammation, change in microenvironment or DNA-damaging toxins. The human microbiome is an integral part of homeostasis. Understanding the mechanisms that cause dysbiosis will enable us to elucidate the pathways that result in malignancy and investigate new treatment modalities.

Lifetime number of years of menstruation as a risk index for postmenopausal endometrial cancer in the Norwegian Women and Cancer Study

INTRODUCTION

Lifetime number of years of menstruation (LNYM) reflects a woman's cumulative exposure to endogenous estrogen and can be used as a measure of the combined effect of reproductive factors related to endometrial cancer (EC) risk.

MATERIAL AND METHODS

We aimed to study the association between LNYM and EC risk among postmenopausal women and calculate the population attributable fraction of EC for different LNYM categories. Our study sample consisted of 117 589 women from the Norwegian Women and Cancer (NOWAC) Study. All women were aged 30-70 years at enrollment and completed a baseline questionnaire between 1991 and 2006. Women were followed up for EC to December 2014 through linkages to national registries. We used Cox proportional hazards models to estimate hazard ratios with 95% confidence intervals (95% CIs), adjusted for potential confounders.

RESULTS

In all, 720 women developed EC. We found a statistically significant, positive dose-response relationship between LNYM and EC, with a 9.1% higher risk for each additional year of LNYM (P for trend < .001). Using the LNYM category ≥40 as a reference, the hazard ratios for LNYM <25, 25-29, 30-34, 35-39 were 0.17 (95% CI 0.22-0.27), 0.25 (95% CI 0.17-0.36), 0.43 (95% CI 0.32-0.58), and 0.68 (95% CI 0.51-0.92), respectively. The association between LNYM and EC was independent of incomplete pregnancies, menopausal hormone therapy, diabetes, and body mass index. When considering the population attributable fraction, 67% of EC was estimated to be attributable to LNYM ≥25 years.

CONCLUSIONS

Our study supports that increasing LNYM is an important and independent predictor of EC risk.

Preoperative assessment of ovarian tumors using a modified multivariate index assay

Background

Preoperative differentiation between benign and malignant masses can be challenging. The aim of this research was to evaluate the performance of a modified multivariate index assay (MIA) in detecting ovarian cancer and to compare the effectiveness of gynecologist assessment, cancer antigen (CA) 125, and MIA for identifying ovarian masses with high suspicion of malignancy.

Results

This prospective observational study included 150 women with ovarian masses who underwent surgery in the Maternity Teaching Hospital from December 2014 to May 2016. Preoperative estimation of modified MIA, assessment by a gynecologist, and CA 125 level correlated with the surgical histopathology. A modified MIA was implemented because of lack of access to the software typically used. Among 150 enrolled women there were 30 cases of malignancy, including 8 cases (26%) of early-stage ovarian cancer and 22 cases (74%) of late-stage cancer. MIA showed high specificity (96.7%) in detecting cancer and a sensitivity of 70%, with a positive predictive value of 84% and a negative predictive value of 92.8%. No significant differences were detected between the MIA results and the histopathology results (P = 0.267). For early-stage ovarian cancer, the sensitivity of MIA was 100% compared with 75% for CA 125 alone.

Conclusion

MIA seems to be effective for evaluation of ovarian tumors with higher specificity and positive predictive value than CA 125 while maintaining high negative predictive value and with only a slightly lower overall sensitivity. For evaluation of early-stage ovarian cancer, MIA showed a much higher sensitivity that markedly outperformed CA 125 alone. This modified MIA strategy may be particularly useful in low resource setting.

Ovarian cancer initially presenting with supra-clavicular lymph node metastasis: A case report

Supra-clavicular lymph node metastasis from ovarian cancer is rare. The present study reports the unique case of a 43-years-old patient who initially presented with left supra-clavicular lymph node metastasis, and was nulliparous. According to fine-needle aspiration cytology of the metastatic left supra-clavicular lymph nodes and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) scan, the patient was diagnosed with poorly differentiated serous carcinoma of ovarian cancer, stage IV. Following two cycles of platinum-based chemotherapy, PET/CT showed that the patient had achieved a complete response. Next, cytoreductive surgery was performed and the postoperative histological findings showed that the patient had achieved a complete pathological response. According to NCCN Clinical Practice Guidelines in Oncology, the patient was stage IV and four cycles of chemotherapy were provided, with no recurrence observed during 3 years of follow-up. This case indicates that patients who initially present with distant metastatic lymph nodes and are nulliparous might have a better prognosis and avoid overtreatment.

The Chemoprevention of Ovarian Cancer: the Need and the Options

PURPOSE OF REVIEW

Ovarian cancer (OvCa) is the most lethal of all gynecological cancers, with a 5-year survival around 46%, mainly due to limitations in early diagnosis and treatment. Consequently, the chemoprevention of OvCa emerges as an important option to control this dismal disease. Here, we discuss the role of risk assessment in the design of chemoprevention strategies for OvCa, describe candidate agents, and assess future directions in this field.

RECENT FINDINGS

OvCa chemoprevention represents an opportunity for all women, especially those at high risk such as carriers of BRCA1 or BRCA2 mutations. The use of oral contraceptives confers substantial protection against OvCa including women at high risk, which increases with longer use. Despite strong evidence for their efficacy, safety concerns and the magnitude of the requisite interventional clinical trials seem to have precluded definitive studies of oral contraceptives for this application. Several other classes of drugs, including non-steroidal anti-inflammatory drugs, retinoids, angiopreventive agents, poly(ADP-ribose) polymerase inhibitors, and tyrosine kinase inhibitors have shown promise for OvCa chemoprevention.

SUMMARY

Currently, no agent is proven by interventional trials to possess chemopreventive properties against OvCa. The key opportunities in the chemoprevention of OvCa include the development of surrogate biomarkers for OvCa, the molecular definition of OvCa risk that will help select those who may benefit the most from chemoprevention, the identification of additional agents likely driven by understanding the molecular pathogenesis of OvCa, and the development of dedicated resources and support mechanisms for OvCa. Overall, there is significant optimism for the future of OvCa chemoprevention.