Pregnancy outcomes and risk of endometrial cancer: A pooled analysis of individual participant data in the Epidemiology of Endometrial Cancer Consortium

Causal relationship between affect disorders and endometrial cancer: a Mendelian randomisation study

BACKGROUND

The aim was to assess the causal relationship between depression and anxiety disorders and endometrial cancer.

METHOD

We performed two-sample Mendelian randomisation analysis using summary statistics from genome-wide association studies to assess associations of major depressive disorder, anxiety and stress-related disorders with endometrial cancer. The genome-wide association studies(GWASs) data were derived from participants of predominantly European ancestry included in the Genome-wide Association Research Collaboration. Inverse variance-weighted, MR-Egger and weighted median MR analyses were performed, together with a range of sensitivity analyses.

RESULTS

Mendelian randomisation analysis showed no statistically significant genetic responsibility effect of anxiety and stress-related disorders on any pathological type of endometrial cancer. Only the effect of major depressive disorder under the inverse variance weighting method increasing the risk of endometrial endometrial cancer (effect 0.004 p = 0.047) and the effect of major depressive disorder under the MR-Egger method decreasing endometrial cancer of all pathology types (effect -0.691 p = 0.015) were statistically significant. Other Mendelian randomisation analyses did not show a statistically significant effect.

CONCLUSION

Major depressive disorder(MDD), anxiety and stress-related disorders(ASRD) are not genetically responsible for endometrial cancer. We consider that emotional disorders may affect endometrial cancer indirectly by affecting body mass index. This study provides us with new insights to better understand the aetiology of endometrial cancer and inform prevention strategies.

Increased risk of subsequent primary lung cancer among female hormone-related cancer patients: A meta-analysis based on over four million cases

BACKGROUND

The incidence rate of lung cancer in women has significantly increased over the past decade, and previous evidence has indicated a significant relationship between the elevated levels of sex hormones and the risk of lung cancer. Therefore, we hypothesized that female hormone-related cancer (FHRC) patients, including breast, endometrial, cervical, and ovarian cancer patients, may experience a higher risk of developing subsequent lung cancer. This meta-analysis aimed to identify the risk of lung cancer among FHRC patients compared to the general population.

METHODS

The PubMed, Web of Science, EMBASE, Cochrane Library, and CNKI databases were searched up to May 11, 2022. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were used to identify the risk of subsequent lung cancer after FHRC. Subgroup analyses based on the follow-up time and tumor type were also conducted.

RESULTS

A total of 58 retrospective cohort studies involving 4,360,723 FHRC participants were included. The pooled results demonstrated that FHRC patients had a significantly increased risk of developing subsequent primary lung cancer (SIR = 1.61, 95% CI: 1.48-1.76, P <0.001). Subgroup analysis revealed an obvious trend of increasing lung cancer risk over time (SIRs for <5 years, ≥5 years, ≥10 years, ≥20 years, and ≥30 years after FHRC: 1.32, 1.59, 1.57, 1.68, and 1.95, respectively). In addition, subgroup analysis stratified by tumor type indicated an increased risk of developing subsequent lung cancer after breast (SIR = 1.25, P <0.001), endometrial (SIR = 1.40, P = 0.019), cervical (SIR = 2.56, P <0.001), and ovarian cancer (SIR = 1.50, P = 0.010).

CONCLUSION

FHRC patients are more likely to develop lung cancer than the general population. Furthermore, the increased risk of subsequent primary lung cancer is more obvious with a longer survival time and is observed in all types of hormone-related cancer.

REGISTRATION

International Platform of Registered Systematic Review and Meta-analysis Protocols: No. INPLASY202270044; https://inplasy.com/.

Parents' age and total fertility rate in selected high-income countries from Europe and North America, 1990-2020

OBJECTIVE

To provide a comprehensive picture of trends in parents' age and total fertility rate in selected most populous high-income countries from Europe and North America.

STUDY DESIGN

Data were retrieved from official statistics published by the United Nations, the World Bank, the European Union (EU), and by national health statistics offices.

RESULTS

Mean maternal age at birth showed increasing trends in all considered countries; in 2020, the highest mean age was observed in Italy (32.2) and Spain (32.3), and the lowest one in the USA (28.8). Mean maternal age at first birth also showed upward trends. In the 1990s, mean age at first birth ranged from 25.5 to 26.9 years, except for the USA where it was below 25 years. The countries with the highest average maternal age at first birth were Italy and Spain, reaching 31 years over the most recent years. Data on mean paternal age at birth were scant. In Germany (2019) it was 34.6 and in the USA (2014) 27.9 years. In Italy, mean paternal age increased from 34.2 in 2000 to 35.5 in 2018, in the UK from 30.7 in 1990 to 33.4 in 2017, and in Canada, a decrease was observed from 29.1 in 2006 to 28.3 in 2011. Finally, Sweden and the USA had the highest fertility rates, around two children in some years, while Italy and Spain had the lowest ones, with less than 1.5 children over the whole period.

CONCLUSIONS

Monitoring of trends in reproductive factors is crucial to gain insight into society from a cultural and sociological point of view and to analyze the impact of these changes on reproductive health and related conditions.

Fraction of cancers attributable to and prevented by reproductive factors and exogenous hormones use in Italy

OBJECTIVE

Endogenous and exogenous hormonal factors have been associated with female breast, genital, and colorectal cancer risk. The aim of the present study is to conduct an evidence-based evaluation of the fraction of cancers attributable to and prevented by exogenous hormonal (i.e., combined oral contraceptives [COC] and combined estrogen-progestogen menopausal therapy [CEPMT]) and reproductive factors (i.e., parity and breastfeeding) in Italy.

STUDY DESIGN

We calculated the population attributable and prevented fractions combining relative risks and prevalence of exposure in Italian women. Italian cancer incidence and mortality data were extracted from national sources and used to estimate the number of cancer cases and deaths attributable to reproductive factors and exogenous hormones in Italy in 2020. For long-term effects, a 20-year latency period was considered.

RESULTS

COC were responsible for 4.4 % of breast and 10.9 % of cervical cancers in women aged 15-44, but also avoided 6.4 % of endometrial, 5.6 % of ovarian, and 2.9 % of colorectal cancers in women of all ages. Overall, COC use prevented 1174 cancer diagnoses and 577 cancer deaths. CEPMT caused 0.4 % of breast cancers at age 45-69. Low parity accounted for 8.1 %, 11.8 % and 15.5 % of breast, endometrial and ovarian cancers, respectively (6267 cases, 1796 deaths). Breastfeeding avoided 6.4 % of breast cancers (3775 cases, 897 deaths).

CONCLUSIONS

Our analysis quantified the complex effects of hormonal and reproductive factors on cancer burden in Italian women.

Optimizing Outcomes through a Multidisciplinary Team Approach in Endometrial Cancer

This study aimed to assess the impact of a multidisciplinary team (MDT) approach on outcomes with endometrial cancer (EC) patients, utilizing 2013-2020 data from the Reggio Emilia Cancer Registry. Recurrence rate, treatments, and outcome indicators were compared between the MDT (319 cases) and non-MDT (324 cases) groups. Among 643 cases, 52.4% were over 65 years old, 98% had microscopic confirmation, and 73% were in stage I. Surgery was performed in 89%, with 41% receiving adjuvant therapies. Recurrence rates (10%) were similar between the two groups, but MDT patients who were older and predominantly in stage I exhibited 79% recurrence within one year (21% in the non-MDT group). Disease-free survival (DFS) showed no significant difference [HR 1.1; 95% CI 0.7-1.6], while differences in overall survival (OS) were notable [HR 1.5; 95% CI 1.0-2.4]. The 5-year OS rates were 87% and 79% in the MDT and non-MDT groups. Comparing the 2013-2015 to 2016-2020 study periods, a shift towards caring for older women, more advanced-stage patients, and those residing outside the metropolitan area, along with a greater number of relapsed cases (from 16% to 76%), were accounted for. These findings underscore the impact of an MDT on EC outcomes, highlighting the evolving patient demographics over time.

Pregnancy complications and endometrial cancer in women with polycystic ovarian syndrome: a Korean National Health Insurance Service study

OBJECTIVE

Polycystic ovarian syndrome is associated with diverse pregnancy related complications and endometrial cancer. However, research on the relationship between pregnancy complications and endometrial cancer in women with polycystic ovarian syndrome is scarce. We aimed to examine the association between gestational diabetes mellitus, pregnancy induced hypertension, and preterm birth and the risk of endometrial cancer in women with polycystic ovarian syndrome.

METHODS

We analyzed data from the National Health Information Database established by the Korean National Health Insurance Service between January 2002 and December 2019. We included women with gestational diabetes mellitus, pregnancy induced hypertension, preterm birth, and endometrial cancer from among the polycystic ovarian syndrome population. All conditions were diagnosed according to the Korean Informative Classification of Diseases, 10th revision codes. Age, area of residence, income, body mass index, waist circumference, total cholesterol, high density lipoprotein, low density lipoprotein, triglycerides, fasting blood sugar, and creatinine levels were included as covariates in the multiple logistic regression analysis.

RESULTS

Of 467 221 women with polycystic ovarian syndrome included, 5099 had endometrial cancer. Age, residence, income, body mass index, waist circumference, total cholesterol, high density lipoprotein, low density lipoprotein, triglycerides, fasting blood sugar, and creatinine levels differed significantly between the endometrial cancer and non-endometrial cancer groups (p≤0.001-0.032). Among the polycystic ovarian syndrome population, the odds ratios (ORs) of endometrial cancer were 1.50, 1.43, and 1.23 in women with a history of gestational diabetes mellitus, pregnancy induced hypertension, and preterm birth, respectively, compared with those without a history of these conditions (OR 1.50, 95% confidence interval (CI) 1.32 to 1.69, p<0.001; 1.43, 1.04 to 1.97, p=0.027; and 1.23, 1.05 to 1.45, p=0.011, respectively).

CONCLUSION

Our results suggest that a history of pregnancy complications (gestational diabetes mellitus, pregnancy induced hypertension, and preterm birth) increases the risk of endometrial cancer in women with polycystic ovarian syndrome.

Risk prediction models for endometrial cancer: development and validation in an international consortium

BACKGROUND

Endometrial cancer risk stratification may help target interventions, screening, or prophylactic hysterectomy to mitigate the rising burden of this cancer. However, existing prediction models have been developed in select cohorts and have not considered genetic factors.

METHODS

We developed endometrial cancer risk prediction models using data on postmenopausal White women aged 45-85 years from 19 case-control studies in the Epidemiology of Endometrial Cancer Consortium (E2C2). Relative risk estimates for predictors were combined with age-specific endometrial cancer incidence rates and estimates for the underlying risk factor distribution. We externally validated the models in 3 cohorts: Nurses' Health Study (NHS), NHS II, and the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

RESULTS

Area under the receiver operating characteristic curves for the epidemiologic model ranged from 0.64 (95% confidence interval [CI] = 0.62 to 0.67) to 0.69 (95% CI = 0.66 to 0.72). Improvements in discrimination from the addition of genetic factors were modest (no change in area under the receiver operating characteristic curves in NHS; PLCO = 0.64 to 0.66). The epidemiologic model was well calibrated in NHS II (overall expected-to-observed ratio [E/O] = 1.09, 95% CI = 0.98 to 1.22) and PLCO (overall E/O = 1.04, 95% CI = 0.95 to 1.13) but poorly calibrated in NHS (overall E/O = 0.55, 95% CI = 0.51 to 0.59).

CONCLUSIONS

Using data from the largest, most heterogeneous study population to date (to our knowledge), prediction models based on epidemiologic factors alone successfully identified women at high risk of endometrial cancer. Genetic factors offered limited improvements in discrimination. Further work is needed to refine this tool for clinical or public health practice and expand these models to multiethnic populations.

Abortion and Female Cancer Risks among Women Aged 20 to 45 Years: A 10-Year Longitudinal Population-Based Cohort Study in Taiwan

BACKGROUND

Female cancers, including breast, cervical, uterine, and ovarian cancer, remain among the ten most common cancers among women worldwide, but the relationship between female cancers and abortion from previous studies is inconsistent. This study aimed to investigate risks of incident female cancers among women aged 20 to 45 years who underwent abortion in Taiwan compared with those who did not.

METHOD

A longitudinal observational cohort study was conducted using three nationwide population-based databases in Taiwan, focusing on 20- to 45-year-old women, with 10 years of follow-up. Matched cohorts were identified with propensity score 1-to-3 matching between 269,050 women who underwent abortion and 807,150 who did not. Multivariable Cox proportional hazard modeling was used for analysis after adjusting for covariates including age, average monthly payroll, fertility, diabetes mellitus, polycystic ovarian syndrome, endometrial hyperplasia, endometriosis, hormone-related drugs, and Charlson comorbidity index.

RESULTS

We found lower risk of uterine cancer (hazard ratio [HR]: 0.77, 95% CI: 0.70-0.85) and ovarian cancer (HR: 0.81, 95% CI: 0.75-0.88), but no significant difference in risk of breast cancer or cervical cancer, among matched abortion compared with non-abortion cohorts. Regarding subgroup analysis, cervical cancer risk was higher for parous women who underwent abortion, and uterine cancer risk was lower for nulliparous women who underwent abortion compared with non-abortion groups.

CONCLUSIONS

Abortion was related to lower uterine and ovarian cancer risk but was not associated with risks of incident breast cancer or cervical cancer. Longer follow-up may be necessary to observe risks of female cancers at older ages.

Comparison of the effectiveness of the levonorgestrel-intrauterine device and oral progestogens on regression of endometrial hyperplasia without atypia

Endometrial hyperplasia is caused by an excess of estrogen unopposed by progesterone. Oral progestogens are traditionally used for endometrial hyperplasia without atypia. However oral progestogen is not always successful at causing regression of endometrial hyperplasia. In addition, cyclic progestogens are less effective in delivering progestogen to the endometrium. Therefore, the levonorgestrel-intrauterine device (LNG-IUD), as an alternative option of delivery progestogen has been introduced in clinical practice. The effectiveness of LNG-IUD in causing regression of endometrial hyperplasia in the short-term had moderate-quality evidence, but the long-term (13 months to two years) effectiveness had low-quality evidence. In this study with relatively large sample size, we compared the effectiveness in the regression of endometrial hyperplasia without atypia for short-term and long-term between the treatment with LNG-IUD and oral progestogens or no treatment. Data on histology or ultrasound from 466 cases who received either LNG-IUD or oral progestogens or were untreated were collected. The primary treatment with LNG-IUD showed a 93% regression rate of endometrial hyperplasia, which was significantly higher than oral progestogens showing a 66% regression rate. The odds ratio of regression of endometrial hyperplasia in cases with LNG-IUD treatment was 7.128 (95%CI: 2.94, 16.76, p < 0.0001), compared to the cases with oral progestogen treatment. The regression rate in untreated cases was 16%. In addition, cases without regression by oral progestogens who then received the alternative treatment option by LNG-IUD also showed a 93% regression rate. While continuously receiving oral progestogens showed a 55% regression rate of endometrial hyperplasia, which was significantly lower than LNG-IUD treatment as an alternative option. Our data reports a significant response on regression of endometrial hyperplasia after LNG-IUD treatment in comparison with oral progestogen treatment.

Pregnancy duration and ovarian cancer risk: A 50-year nationwide cohort study

A woman's reproductive history is strongly associated with her risk of ovarian cancer. However, it is unclear how pregnancies of different duration impact a woman's ovarian cancer risk, and therefore, what part of a pregnancy explains the protective effect. Using a cohort of all Danish women followed from 1968 to 2018, with prospectively registered information on reproductive history (eg, gestational duration of pregnancies, tubal ligation and resection and hormonal pharmaceutical use), we investigated the effect of pregnancy duration on ovarian cancer risk. We adjusted for potential confounders, such as age at pregnancy and time since pregnancy, using log-linear Poisson regression to isolate the effect of pregnancy duration on ovarian cancer risk. Among 2.5 million Danish women with 4.4 million pregnancies, a pregnancy was associated with a reduction of ovarian cancer risk of 21% (95% CI, 14%-28%), 26% (95% CI, 21%-31%), 12% (95% CI, 7%-17%) and 3% (95% CI, -5% to 11%) compared to one less, for the first, second, third and fourth pregnancy, respectively (P < .001 for heterogeneity), with similar effects of induced abortions, spontaneous abortions and childbirths. Sensitivity analysis of age at pregnancy, time since pregnancy and other potential confounders did not change these findings. The reduced ovarian cancer risk associated with pregnancy is primarily driven by the first three pregnancies, with similar effects of induced abortion, spontaneous abortions and childbirth, suggesting that mainly exposure to early pregnancy factors, and not pregnancy duration, protect against ovarian cancer.

Mendelian randomization analysis of factors related to ovulation and reproductive function and endometrial cancer risk

BACKGROUND

Observational epidemiological studies suggest a link between several factors related to ovulation and reproductive function and endometrial cancer (EC) risk; however, it is not clear whether these relationships are causal, and whether the risk factors act independently of each other. The aim of this study was to investigate putative causal relationships between the number of live births, age at last live birth, and years ovulating and EC risk.  METHODS: We conducted a series of observational analyses to investigate various risk factors and EC risk in the UK Biobank (UKBB). Additionally, multivariate analysis was performed to elucidate the relationship between the number of live births, age at last live birth, and years ovulating and other related factors such as age at natural menopause, age at menarche, and body mass index (BMI). Secondly, we used Mendelian randomization (MR) to assess if these observed relationships were causal. Genome-wide significant single nucleotide polymorphisms (SNPs) were extracted from previous studies of woman's number of live births, age at menopause and menarche, and BMI. We conducted a genome-wide association analysis using the UKBB to identify SNPs associated with years ovulating, years using the contraceptive pill, and age at last live birth.

RESULTS

We found evidence for a causal effect of the number of live births (inverse variance weighted (IVW) odds ratio (OR): 0.537, p = 0.006), the number of years ovulating (IVW OR: 1.051, p = 0.014), in addition to the known risk factors BMI, age at menarche, and age at menopause on EC risk in the univariate MR analyses. Due to the close relationships between these factors, we followed up with multivariable MR (MVMR) analysis. Results from the MVMR analysis showed that number of live births had a causal effect on EC risk (OR: 0.783, p = 0.036) independent of BMI, age at menarche and age at menopause.

CONCLUSIONS

MVMR analysis showed that the number of live births causally reduced the risk of EC.

Understanding How Pregnancy Protects Against Ovarian and Endometrial Cancer Development: Fetal Antigens May Be Involved

It is well known that many factors, including infertility, obesity, type 2 diabetes, and family history of cancer, increase the risk of developing endometrial and ovarian cancer. However, multiparous women are known to have a lower risk of developing either ovarian or endometrial cancer than nonparous women. The lack of ovulation and shifting of sex hormonal balance, with decreased estrogen levels and increased progesterone levels during pregnancy, has traditionally been thought to be the major contributor to this decreased risk. However, in reality, the mechanisms underlying this phenomenon are relatively unknown. Increasing evidence suggests that endocrine factors are unlikely to completely explain the protective effect of pregnancies, and that multiple other nonendocrine mechanisms including fetal antigens and the newly proposed dormant cells hypothesis may also be involved. In this review, we summarize recent evidence and describe the potential underlying mechanisms that may explain how pregnancy protects against the development of ovarian and endometrial cancers in women's later life.

The histological type of endometrial cancer is not associated with menopause status at diagnosis

The latest evidence suggests that type 2 endometrial cancer may not be completely oestrogen-independent, indicating that the status of hormonal change may not be associated with the traditional classification of endometrial cancer, including the histological subtypes. However, this has not been investigated. Menopause is commonly considered a state of hormonal change in women. In the present study, we investigated the association of menopause with the histological types of endometrial cancer. Data on the histological type, menopause status at diagnosis, age at diagnosis, parity, body mass index (BMI), and overall survival rate from 2122 cases were collected. The difference in risk in developing type 1 or type 2 endometrial cancer between premenopausal and postmenopausal patients was 5.457%. A statistical difference in the association of menopause with the histological types between the two groups was seen in endometrioid and serous carcinoma, with a risk difference of 5.6 or 3.8%. A statistical difference in the association of menopause with parity between the groups was only seen in endometrioid and adenosquamous carcinoma, with a risk difference of 7.1 or 3.7%. However, BMI was not associated with histological type and the overall survival rate was not associated with menopause (P=0.764). We reported a relatively small difference in the association of menopause with type 1 or type 2, or the histological types of endometrial cancer. The survival rate was not associated with menopause. Our study suggests that menopause status at diagnosis was not strongly associated with the histological subtypes of endometrial cancer.

Risk factors of endometrial cancer in patients with endometrial hyperplasia: implication for clinical treatments

Background

Endometrial hyperplasia (EH) is commonly-seen in the patients with endometrial cancer (EC), we aimed to evaluated the risk factors of EC in patients with EH, to provide evidence to the clinical prevention and treatment of EC.

Methods

This study was a retrospective study design. EH patients confirmed by pathological examinations and treated with hysterectomy in our hospital from June 1, 2018 to February 28, 2021 were included. The clinical characteristics of EC and no-EC patients were compared and analyzed. Logistics regression analyses were conducted to evaluate the risk factors of EC in patients with EH.

Results

A total of 228 EH patients were included, the incidence of EC in the EH patients was 31.58%. There were significant differences in the age, BMI, diabetes, hypertension and pathology of EH between EC and no EC groups (all P < 0.05), no significant differences in the hyperlipidemia, preoperative CA₁₂₅, number of deliveries, menopause and endometrial thickness between EC and no EC groups were found (all P > 0.05). Logistic regression analyses indicated that age > 50 y (OR 3.064, 95% CI 1.945–5.931), BMI ≥ 25 kg/m² (OR 2.705, 95% CI 1.121–3.889), diabetes (OR 3.049, 95% CI 1.781–5.114), hypertension (OR 2.725, 95% CI 1.108–3.431) and severe hyperplasia (OR 3.181, 95% CI 1.496–4.228) were the risk factors of EC in patients with EH (all P < 0.05).

Conclusions

The risk of EC in EH patients is high, especially for those patients with age > 50 y, BMI ≥ 25 kg/m², diabetes, hypertension and severe hyperplasia, special attentions should be paid for occurrence of EC and early diagnosis and early treatment are needed for those patients.

Reproductive Pattern of Parous Women and the Risk of Cancer in Later Life

We assessed the risk of any and site-specific cancers in a case-control study of parous women living in northeast Scotland in relation to: total number of pregnancies, cumulative time pregnant, age at first delivery and interpregnancy interval. We analysed 6430 women with cancer and 6430 age-matched controls. After adjustment for confounders, women with increasing number of pregnancies had similar odds of cancer diagnosis as women with only one pregnancy. The adjusted odds of cancer diagnosis were no higher in women with cumulative pregnancy time 50-150 weeks compared to those pregnant ≤ 50 weeks. Compared with women who had their first delivery at or before 20 years of age, the adjusted odds ratio (AOR) among those aged 21-25 years was 0.81, 95% CI 0.74, 0.88; 26-30 years AOR 0.77, 95% CI 0.69, 0.86; >30 years AOR 0.63, 95% CI 0.55, 0.73. After adjustment, the odds of having any cancer were higher in women who had an inter-pregnancy interval >3 years compared to those with no subsequent pregnancy (AOR 1.17, 95% CI 1.05, 1.30). Older age at first pregnancy was associated with increased risk of breast and gastrointestinal cancer, and reduced risk of invasive cervical, carcinoma in situ of the cervix and respiratory cancer.