Age at last birth and risk of developing epithelial ovarian cancer: a meta-analysis

Global epidemiology of epithelial ovarian cancer

Globally, ovarian cancer is the eighth most common cancer in women, accounting for an estimated 3.7% of cases and 4.7% of cancer deaths in 2020. Until the early 2000s, age-standardized incidence was highest in northern Europe and North America, but this trend has changed; incidence is now declining in these regions and increasing in parts of eastern Europe and Asia. Ovarian cancer is a very heterogeneous disease and, even among the most common type, namely epithelial ovarian cancer, five major clinically and genetically distinct histotypes exist. Most high-grade serous ovarian carcinomas are now recognized to originate in the fimbrial ends of the fallopian tube. This knowledge has led to more cancers being coded as fallopian tube in origin, which probably explains some of the apparent declines in ovarian cancer incidence, particularly in high-income countries; however, it also suggests that opportunistic salpingectomy offers an important opportunity for prevention. The five histotypes share several reproductive and hormonal risk factors, although differences also exist. In this Review, we summarize the epidemiology of this complex disease, comparing the different histotypes, and consider the potential for prevention. We also discuss how changes in the prevalence of risk and protective factors might have contributed to the observed changes in incidence and what this might mean for incidence in the future.

Incessant ovulation: a review of its importance in predicting cancer risk

Estrous cycles are recurring changes in therian mammals induced by estrogen, progesterone, and other hormones culminating in endometrial proliferation, ovulation, and implantation if fertilization occurred. In women, the estrous cycle is the menstrual cycle; but, unlike most mammals, the end of an infertile cycle is marked by endometrial sloughing and the start of another without an anestrous phase. Women stop cycling at menopause, while in most mammals, cycles continue until death. Epidemiologic studies identified menarche, menopause, births, lactation, and oral contraceptive (OC) use as key risk factors for ovarian, breast, and endometrial cancers. A composite variable was created to estimate the number of cycles not interrupted by events that stop ovulation. Captured by the phrase "incessant ovulation", repetitive cycles were first postulated to affect ovarian cancer risk and later extended to breast and endometrial cancers. These associations could be explained by cumulative effects of repetitive tissue changes within reproductive organs, immune consequences of repetitive ovulation through the glycoprotein mucin 1, and residual effects of past ovulations that enhance ovarian production of testosterone. The latter two pathways could affect the risk for cancers in other organs not considered "reproductive".

Maternal age at birth of last child and cardiovascular disease mortality later in life among a national cohort of postmenopausal women from the United States

Maternal age at last birth of child is increasing in the United States, and it has been reported to influence future chronic diseases. In this study of nationally-representative sample of postmenopausal women, there was no conclusive association between maternal age at last birth of child and cardiovascular disease mortality later in life.

Objective

Maternal age at last birth (ALB) of child is increasing in the United States, and it has been reported to influence future chronic diseases. However, the relationship of ALB and cardiovascular disease (CVD) events later in life has not been widely studied. We evaluated the association of ALB with CVD mortality.

Methods

Data were from 7,971 parous postmenopausal women older than 45 years who participated in the US National Health and Nutritional Examination Survey from 1999 to 2018 and had mortality follow-up data through to December 31, 2019. ALB was self-reported, whereas CVD mortality was assessed using International Classification of Diseases codes. Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI).

Results

The mean age of participants was 63 ± 9.8 years, with 9.5% being non-Hispanic Black, 9.7% being Hispanic women, and 21% reporting ALB ≥35 years. During a median follow-up of 8.1 years, 443 participants died from CVD. In age-adjusted models, CVD mortality was elevated for women with ALB of <25 years (HR, 1.68; 95% CI, 1.23-2.29) and ALB of ≥35 years (HR, 1.37; 95% CI, 1.00-1.88). However, after additional adjustment for race and ethnicity, foreign born, education, marital status, poverty income ratio, parity, smoking status, age at menarche, oral contraceptive pills use and family history of myocardial infarction, these estimates were attenuated resulting in no association between ALB and CVD mortality.

Conclusions

In this study of nationally representative sample of postmenopausal women, there was no conclusive association between maternal ALB and CVD mortality later in life.

Investigation of cytotoxic and apoptotic effects of disodium pentaborate decahydrate on ovarian cancer cells and assessment of gene profiling

After revealing the anti-cancer properties of boron, which is included in the category of essential elements for human health by the World Health Organization, the therapeutic potential of boron compounds has been begun to be evaluated, and its molecular effect mechanisms have still been among the research subjects. In ovarian cancer, mutations or amplifications frequently occur in the PI3K/Akt/mTOR pathway components, and dysregulation of this pathway is shown among the causes of treatment failure. In the present study, it was aimed to investigate the anti-cancer properties of boron-containing DPD in SKOV3 cells, which is an epithelial ovarian cancer model, through PI3K/AKT/mTOR pathway. The cytotoxic activity of DPD in SKOV3 cells was evaluated by WST-1 test, apoptotic effect by Annexin V and JC-1 test. The gene expressions associated with PI3K/AKT/mTOR pathway were determined by real-time qRT-PCR. In SKOV3 cells, the IC₅₀ value of DPD was found to be 6.7 mM, 5.6 mM, and 5.2 mM at 24th, 48th and 72nd hour, respectively. Compared with the untreated control group, DPD treatment was found to induce apoptosis 2.6-fold and increase mitochondrial membrane depolarization 4.5-fold. DPD treatment was found to downregulate PIK3CA, PIK3CG, AKT2, IGF1, IRS1, MAPK3, HIF-1, VEGFC, CAB39, CAB39L, STRADB, PRKAB2, PRKAG3, TELO2, RICTOR, MLST8, and EIF4B genes and upregulate TP53, GSK3B, FKBP8, TSC2, ULK1, and ULK2 genes. These results draw attention to the therapeutic potential of DPD, which is frequently exposed in daily life, in epithelial ovarian cancer and show that it can be a candidate compound in combination with chemotherapeutics.

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.

Childbearing Biographies and Midlife Women's Health

OBJECTIVES

We introduce a "childbearing biography" approach to show how multiple childbearing characteristics cluster in ways significant for midlife health.

METHODS

We analyze the National Longitudinal Survey of Youth 1979 (NLSY79; N = 3992) using mixed-mode Latent Class Analysis with eight childbearing variables (e.g., age at first birth, parity, birth spacing, and mistimed births) to identify how childbearing biographies are associated with midlife health, adjusting for key covariates-including socioeconomic status (SES) and relationship history.

RESULTS

We identify six childbearing biographies: (1) early compressed, (2) staggered, (3) extended high parity, (4) later, (5) married planned, and (6) childfree. Childbearing biographies are strongly associated with physical health but not mental health, with differences primarily explained by SES.

DISCUSSION

Different childbearing biographies are related to physical health inequalities above what is demonstrated by the typical use of one or two childbearing measures, providing a new perspective into the growing health gap among aging midlife women.

Age at last birth and risk of developing breast cancer: a meta-analysis

OBJECTIVES

Results from epidemiologic studies on age at last birth (ALB) and the risk of developing breast cancer were inconsistent. Therefore, we conducted this meta-analysis to evaluate the association between ALB and the risk of developing breast cancer quantitatively.

METHODS

Relevant articles published up to May 2019 were identified by searching systematically in PubMed, Web of Science, China National Knowledge Infrastructure, and Wan Fang Med Online. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model. Dose-response relationship was assessed by restricted cubic spline model.

RESULTS

Fourteen studies with 132 133 cases and 1 314 005 participants were eligible for this meta-analysis. The pooled RR (95% CI) of breast cancer for the highest vs. the lowest stratification of ALB was 1.22 (1.04-1.42). In the subgroup analysis, significant positive associations were also found in studies conducted in Europe (RR: 1.21, 95% CI: 1.06-1.38), studies with results adjusted for parity (RR: 1.26, 95% CI: 1.04-1.54), and studies with results adjusted for age at first birth (RR: 1.37, 95% CI: 1.08-1.74). The results of the dose-response analysis indicated that the departure from linearity was NS between ALB and the risk of breast cancer (Pnonlinearity = 0.711), but the linear associations were NS.

CONCLUSION

This meta-analysis suggested that ALB was positively associated with the risk of breast cancer. The risk of developing breast cancer increased gradually with the ALB for women. Our findings may have implications for family planning.

A Novel Clinical Nomogram for Predicting Cancer-Specific Survival in Adult Patients After Primary Surgery for Epithelial Ovarian Cancer: A Real-World Analysis Based on the Surveillance, Epidemiology, and End Results Database and External Validation in a Tertiary Center

Background

The present study aimed to construct and validate a nomogram that can be used to predict cancer-specific survival (CSS) in patients with epithelial ovarian cancer (EOC).

Methods

A total of 7,129 adult patients with EOC were extracted from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Patients were randomly divided into the training and validation cohorts (7:3). Cox regression was conducted to evaluate prognostic factors of CSS. The internal validation of the nomogram was performed using concordance index (C-index), AUC, calibration curves, and decision curve analyses (DCAs). Data from 53 adult EOC patients at Shengjing Hospital of China Medical University from 2008 to 2012 were collected for external verification. Kaplan-Meier curves were plotted to compare survival outcomes among risk subgroups.

Results

Age, grade, histological types, stage, residual lesion size, number of regional lymph nodes resected, number of positive lymph nodes, and chemotherapy were independent risk factors for CSS. Based on the above factors, we constructed a nomogram. The C-indices of the training cohort, internal validation cohort, and external verification group were 0.763, 0.750, and 0.920, respectively. The calibration curve indicated good agreement between the nomogram prediction and actual survival. AUC and DCA results indicated great clinical usefulness of the nomogram. The differences in the Kaplan-Meier curves among different risk subgroups were statistically significant.

Conclusions

We constructed a nomogram to predict CSS in adult patients with EOC after primary surgery, which can assist in counseling and guiding treatment decision making.