Metabolic syndrome and endometrial cancer risk

Hypertension and Risk of Endometrial Cancer: A Pooled Analysis in the Epidemiology of Endometrial Cancer Consortium (E2C2)

BACKGROUND

The incidence rates of endometrial cancer are increasing, which may partly be explained by the rising prevalence of obesity, an established risk factor for endometrial cancer. Hypertension, another component of metabolic syndrome, is also increasing in prevalence, and emerging evidence suggests that it may be associated with the development of certain cancers. The role of hypertension independent of other components of metabolic syndrome in the etiology of endometrial cancer remains unclear. In this study, we evaluated hypertension as an independent risk factor for endometrial cancer and whether this association is modified by other established risk factors.

METHODS

We included 15,631 endometrial cancer cases and 42,239 controls matched on age, race, and study-specific factors from 29 studies in the Epidemiology of Endometrial Cancer Consortium. We used multivariable unconditional logistic regression models to estimate ORs and 95% confidence intervals (CI) to evaluate the association between hypertension and endometrial cancer and whether this association differed by study design, race/ethnicity, body mass index, diabetes status, smoking status, or reproductive factors.

RESULTS

Hypertension was associated with an increased risk of endometrial cancer (OR, 1.14; 95% CI, 1.09-1.19). There was significant heterogeneity by study design (Phet < 0.01), with a stronger magnitude of association observed among case-control versus cohort studies. Stronger associations were also noted for pre-/perimenopausal women and never users of postmenopausal hormone therapy.

CONCLUSIONS

Hypertension is associated with endometrial cancer risk independently from known risk factors. Future research should focus on biologic mechanisms underlying this association.

IMPACT

This study provides evidence that hypertension may be an independent risk factor for endometrial cancer.

Metformin for endometrial hyperplasia

BACKGROUND

Endometrial cancer is one of the most common gynaecological cancers in the world. Rates of endometrial cancer are rising, in part because of rising obesity rates. Endometrial hyperplasia is a precancerous condition in women that can lead to endometrial cancer if left untreated. Endometrial hyperplasia occurs more commonly than endometrial cancer. Progesterone tablets that are currently used to treat women with endometrial hyperplasia are associated with adverse effects in up to 84% of women. A levonorgestrel intrauterine device may improve compliance, but it is invasive, is not acceptable to all women, and is associated with irregular vaginal bleeding in 82% of cases. Therefore, an alternative treatment for women with endometrial hyperplasia is needed. Metformin, a drug that is often used to treat people with diabetes, has been shown, in some human studies, to reverse endometrial hyperplasia. However, the effectiveness and safety of metformin for treatment of endometrial hyperplasia remain uncertain. This is an update of a review first published in 2017.

OBJECTIVES

To determine the effectiveness and safety of metformin in treating women with endometrial hyperplasia.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Specialised Register, CENTRAL, MEDLINE, PubMed, Embase, Google Scholar, OpenGrey, LILACS, and two trials registers from inception to 5 September 2022. We searched the bibliographies of all relevant studies, and contacted experts in the field for any additional trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cross-over trials comparing metformin (used alone or in combination with other medical therapies) versus placebo, no treatment, any conventional medical treatment, or any other active intervention for women with histologically confirmed endometrial hyperplasia of any type.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility, extracted data from included studies, assessed the risk of bias in the included studies, and assessed the certainty of the evidence for each outcome. We resolved disagreements by discussion or by deferring to a third review author. When study details were missing, review authors contacted the study authors. The primary outcome of this review was regression of endometrial hyperplasia histology (with or without atypia) towards normal histology.

MAIN RESULTS

We included seven RCTs, in which a total of 387 women took part. In the comparison, Metformin plus megestrol versus megestrol alone, we rated the certainty of the evidence as low for the outcome, regression of endometrial hyperplasia. We rated the quality of the evidence as very low for the rest of the outcomes, in all three comparisons. Although there was a low risk of selection bias, there was a high risk of bias in the blinding of personnel and outcome assessment (performance bias and detection bias) in many studies. This update identified four new RCTs and six ongoing RCTs. Metformin versus megestrol We are uncertain whether metformin increases the regression of endometrial hyperplasia towards normal histology over megestrol (odds ratio (OR) 4.89, 95% confidence interval (CI) 1.56 to 15.32; P = 0.006; 2 RCTs, 83 participants; I² = 7%; very low-certainty evidence). This evidence suggests that if the rate of regression with megestrol is 61%, the rate of regression with metformin would be between 71% and 96%. It is unresolved whether metformin results in different rates of abnormal uterine bleeding or hysterectomy compared to megestrol. No study in this comparison reported progression of hyperplasia to endometrial cancer, recurrence of endometrial hyperplasia, health-related quality of life, or adverse effects during treatment. Metformin plus megestrol versus megestrol monotherapy The combination of metformin and megestrol may enhance the regression of endometrial hyperplasia towards normal histology more than megestrol alone (OR 3.27, 95% CI 1.65 to 6.51; P = 0.0007; 4 RCTs, 258 participants; I² = 0%, low-certainty evidence). This suggests that if the rate of regression with megestrol monotherapy is 54%, the rate of regression with the addition of metformin would be between 66% and 84%. In one study, 3/8 (37.5%) of participants who took metformin had nausea that settled without further treatment. It is unresolved whether the combination of metformin and megestrol results in different rates of recurrence of endometrial hyperplasia, progression of endometrial hyperplasia to endometrial cancer, or hysterectomy compared to megestrol monotherapy. No study in this comparison reported abnormal uterine bleeding, or health-related quality of life. Metformin plus levonorgestrel (intrauterine system) versus levonorgestrel (intrauterine system) monotherapy We are uncertain whether there is a difference between groups in the regression of endometrial hyperplasia towards normal histology (OR 0.29, 95% CI 0.01 to 7.56; 1 RCT, 46 participants; very low-certainty evidence). This evidence suggests that if the rate of regression with levonorgestrel monotherapy is 96%, the rate of regression with the addition of metformin would be between 73% and 100%. It is unresolved whether the combination of metformin and levonorgestrel results in different rates of abnormal uterine bleeding, hysterectomy, or the development of adverse effects during treatment compared to levonorgestrel monotherapy. No study in this comparison reported recurrence of endometrial hyperplasia, progression of hyperplasia to endometrial cancer, or health-related quality of life.

AUTHORS' CONCLUSIONS

Review authors found insufficient evidence to either support or refute the use of metformin, specifically megestrol acetate, given alone or in combination with standard therapy, for the treatment of women with endometrial hyperplasia. Robustly designed and adequately powered randomised controlled trials, yielding long-term outcome data are still needed to address this clinical question.

Prognostic impact of metabolic syndrome in patients with primary endometrial cancer: a retrospective bicentric study

PURPOSE

Endometrial cancer (EC) is the most common gynaecological cancer. Its incidence has been rising over the years with ageing and increased obesity of the high-income countries' populations. Metabolic syndrome (MetS) has been suggested to be associated with EC. The aim of this study was to assess whether MetS has a significant impact on oncological outcome in patients with EC.

METHODS

This retrospective study included patients treated for EC between January 2010 and December 2020 in two referral oncological centers. Obesity, arterial hypertension (AH) and diabetes mellitus (DM) were criteria for the definition of MetS. The impact of MetS on progression free survival (PFS) and overall survival (OS) was assessed with log-rank test and Cox regression analyses.

RESULTS

Among the 415 patients with a median age of 64, 38 (9.2%) fulfilled the criteria for MetS. The median follow-up time was 43 months. Patients suffering from MetS did not show any significant differences regarding PFS (36.0 vs. 40.0 months, HR: 1.49, 95% CI 0.79-2.80 P = 0.210) and OS (38.0 vs. 43.0 months, HR: 1.66, 95% CI 0.97-2.87, P = 0.063) compared to patients without MetS. Patients with obesity alone had a significantly shorter median PFS compared to patients without obesity (34.5 vs. 44.0 months, P = 0.029). AH and DM separately had no significant impact on PFS or OS (p > 0.05).

CONCLUSION

In our analysis, MetS in patients with EC was not associated with impaired oncological outcome. However, our findings show that obesity itself is an important comorbidity associated with significantly reduced PFS.

The association between endometrial cancer and subsequent diabetic retinopathy severity: A retrospective nationwide study

OBJECTIVE

The endometrial cancer is a disorder with elevated oxidative stress. The high oxidative stress resulting from hyperglycemia can lead to diabetic retinopathy (DR) development which is a complication of type 2 diabetes mellitus. Accordingly, we aim to evaluate the potential relationship between the endometrial cancer and following DR development.

METHODS

A retrospective cohort study was conducted using the National Health Insurance Research Database (NHIRD) of Taiwan. Individuals diagnosed with endometrial cancer were matched to the non-endometrial cancer patients in a 1:4 ratio. The major outcomes are the presence of DR, diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) according to diagnostic codes. Cox proportional hazard regression was used to show the adjusted hazard ratio (aHR) with 95% confidence interval (CI) of major outcomes between groups.

RESULTS

There were 99 (2.3%), 20 (0.5%), and 14 (0.3%) cases with DR, DME and PDR in the endometrial cancer group, respectively. Another 303 (1.8%), 35 (0.2%), and 27 (0.2%) with DR, DME and PDR were observed in the control group, respectively. The endometrial cancer group revealed a significantly higher incidence of DR compared with the control group (aHR 1.51, 95% CI 1.20-1.90, P < 0.001). The cumulative probability of DR was also higher in the endometrial cancer group than in the control group (P < 0.001). The relationship between endometrial cancer and DR was significantly higher in patients aged over 70 years (P = 0.008). In addition, a higher incidence of DR was found during the first 5 years after the endometrial cancer diagnosis (P < 0.001).

CONCLUSIONS

The endometrial cancer correlates to a higher incidence of subsequent DR, especially within first 5 years of endometrial cancer diagnosis.

Hypertension and hyperglycaemia are positively correlated with local invasion of early cervical cancer

Background

Metabolic disorders are involved in the development of numerous cancers, but their association with the progression of cervical cancer is unclear. This study aims to investigate the association between metabolic disorders and the pathological risk factors and survival in patients with early cervical cancer.

Methods

Patients with FIGO IB1 (2009) primary cervical cancer who underwent radical hysterectomy and systematic pelvic lymph node dissection at our institution from October 2014 to December 2017 were included retrospectively. Clinical data regarding the metabolic syndrome and surgical pathology of the patient were collected. The correlations between metabolic disorders (hypertension, hyperglycemia, and obesity) and clinicopathological characteristics as well as survival after surgery were analyzed.

Results

The study included 246 patients with clinical IB1 cervical cancer, 111 (45.1%) of whom had at least one of the comorbidities of hypertension, obesity, or hyperglycemia. Hypertension was positively correlated with parametrial invasion and poorly differentiated histology; hyperglycemia was positively correlated with stromal invasion; obesity was negatively associated with lymph node metastasis; but arbitrary disorder did not show any correlation with pathologic features. Hypertension was an independent risk factor for parametrial invasion (OR=6.54, 95% CI: 1.60-26.69); hyperglycemia was an independent risk factor for stromal invasion (OR=2.05, 95% CI: 1.07-3.95); and obesity was an independent protective factor for lymph node metastasis (OR=0.07, 95% CI: 0.01-0.60). Moreover, the patients with hypertension had a significantly lower 5-year OS rate (70.0% vs. 95.3%, P<0.0001) and a significantly lower 5-year PFS rate than those without hypertension (70.0% vs. 91.2%, P=0.010).

Conclusion

Hypertension and hyperglycemia are positively associated with local invasion of early cervical cancer, which need to be verified in multi-center, large scale studies.

Association of coffee and caffeine consumption with risk and prognosis of endometrial cancer and its subgroups: a Mendelian randomization

Background

Previous studies have not established potential causal associations between coffee and caffeine consumption in endometrial cancer (EC) and its subgroups. Therefore, we used a two-sample MR method to assess the causal association between coffee and caffeine consumption and EC risk. We also evaluated the association between these genetically predicted exposures and EC prognosis.

Materials and methods

This study used 12 and two independent single-nucleotide polymorphisms (SNPs) associated with coffee and caffeine consumption as instrumental variables at a genome-wide significance level of p < 5 × 10-8. The EC Association Consortium (ECAC) performed a genome-wide association study (GWAS) analysis of 12,906 cases and 108,979 controls. FinnGen Consortium performed a GWAS analysis of 1,967 EC cases and 167,189 controls. The primary technique we employed was inverse-variance weighted, followed by the weighted median, MR-Egger regression, and MR robust adjusted profile score methods. We used the MR pleiotropy residual sum, Outlier test, and MR-Egger regression to assess Outlier and pleiotropic variants. We also conducted a sensitivity analysis through the leave-one-out method.

Results

Genetically predicted coffee consumption was not associated with EC and its subgroups in the ECAC, and the association was consistent in the FinnGen consortium. After excluding eight SNPs with confounding factors, the study performed sensitivity analyses, delivering consistent results. We also observed that caffeine consumption was not correlated with EC risk. As confirmed by MR analysis, selected SNPs determined that most do not significantly impact the likelihood of developing EC.

Conclusion

Our study indicated no convincing evidence supports coffee and caffeine consumption causing EC or impacting its prognosis. More studies are needed to validate the results.

Development and validation of a prognostic model based on metabolic risk score to predict overall survival of endometrial cancer in Chinese patients

OBJECTIVE

Metabolic syndrome (MetS) is closely related to the increased risk and poor prognosis of endometrial cancer (EC). The purpose of this study was to analyze the relationship between metabolic risk score (MRS) and EC, and establish a predictive model to predict the prognosis of EC.

METHODS

A retrospective study was designed of 834 patients admitted between January 2004 to December 2019. Univariate and multivariate Cox analysis were performed to screen independent prognostic factors for overall survival (OS). A predictive nomogram is built based on independent risk factors for OS. Consistency index (C-index), calibration plots and receiver operating characteristic curve were used to evaluate the predictive accuracy of the nomogram.

RESULTS

The patients were randomly divided into training cohort (n=556) and validation cohort (n=278). The MRS of EC patients, ranging from -8 to 15, was calculated. Univariate and multivariate Cox analysis indicated that age, MRS, FIGO stage, and tumor grade were independent risk factors for OS (p<0.05). The Kaplan-Meier analysis demonstrated that EC patients with low score showed a better prognosis in OS. Then, a nomogram was established and validated based on the above four variables. The C-index of nomogram were 0.819 and 0.829 in the training and validation cohorts, respectively. Patients with high-risk score had a worse OS according to the nomogram.

CONCLUSION

We constructed and validated a prognostic model based on MRS and clinical prognostic factors to predict the OS of EC patients accurately, which may help clinicians personalize prognostic assessments and effective clinical decisions.

Pyroptosis: the dawn of a new era in endometrial cancer treatment

Endometrial cancer (EC) is a malignancy of the inner epithelial lining of the uterus. While early-stage EC is often curable through surgery, the management of advanced, recurrent and metastatic EC poses significant challenges and is associated with a poor prognosis. Pyroptosis, an emerging form of programmed cell death, is characterized by the cleavage of gasdermin proteins, inducing the formation of extensive gasdermin pores in the cell membrane and the leakage of interleukin-1β (IL-1β) and interleukin-18 (IL-18), consequently causing cell swelling, lysis and death. It has been found to be implicated in the occurrence and progression of almost all tumors. Recent studies have demonstrated that regulating tumor cells pyroptosis can exploit synergies function with traditional tumor treatments. This paper provides an overview of the research progress made in molecular mechanisms of pyroptosis. It then discusses the role of pyroptosis and its components in initiation and progression of endometrial cancer, emphasizing recent insights into the underlying mechanisms and highlighting unresolved questions. Furthermore, it explores the potential value of pyroptosis in the treatment of endometrial cancer, considering its current application in tumor radiotherapy, chemotherapy, targeted therapy and immunotherapy.

Global incidence and mortality trends of corpus uteri cancer and associations with gross domestic product, human development index, lifestyle, and metabolic risk factors

OBJECTIVE

To evaluate the worldwide distribution, risk factors, and temporal trends of corpus uteri cancer for different countries and age groups.

METHOD

Data relating to corpus uteri cancer in 2020 were retrieved from the Global Cancer Observatory database. Data from Cancer Incidence in Five Continents and the WHO mortality database were used for trend analysis. Age-standardized rates (ASR, per 100 000 persons) were calculated for incidence and mortality. Joinpoint regression analysis was used to estimate the 10-year annual average percent change (AAPC).

RESULTS

A total of 417 367 new cases and 97 370 new deaths of corpus uteri cancer were reported globally in 2020. The highest incidence was observed in high-income countries. Higher ASR of mortality of corpus uteri cancer was associated with a higher gross domestic product per capita, higher Human Development Index, and higher prevalence of smoking, alcohol drinking, physical inactivity, obesity, hypertension, diabetes, and lipid disorders. There was a substantial increasing trend of corpus uteri cancer, with the largest AAPC in incidence found in Japan, followed by India, Chile, Korea, and Thailand.

CONCLUSION

The incidence and mortality of corpus uteri cancer have been increasing substantially for the past 10 years. Intensive lifestyle modifications are needed, especially among younger women.

Metabolic syndrome score as an indicator in a predictive nomogram for lymph node metastasis in endometrial cancer

BACKGROUND

Lymph node metastasis (LNM) is an important factor affecting endometrial cancer (EC) prognosis. Current controversy exists as to how to accurately assess the risk of lymphatic metastasis. Metabolic syndrome has been considered a risk factor for endometrial cancer, yet its effect on LNM remains elusive. We developed a nomogram integrating metabolic syndrome indicators with other crucial variables to predict lymph node metastasis in endometrial cancer.

METHODS

This study is based on patients diagnosed with EC in Peking University People's Hospital between January 2004 and December 2020. A total of 1076 patients diagnosed with EC and who underwent staging surgery were divided into training and validation cohorts according to the ratio of 2:1. Univariate and multivariate logistic regression analyses were used to determine the significant predictive factors.

RESULTS

The prediction nomogram included MSR, positive peritoneal cytology, lymph vascular space invasion, endometrioid histological type, tumor size >  = 2 cm, myometrial invasion >  = 50%, cervical stromal invasion, and tumor grade. In the training group, the area under the curve (AUC) of the nomogram and Mayo criteria were 0.85 (95% CI: 0.81-0.90) and 0.77 (95% CI: 0.77-0.83), respectively (P < 0.01). In the validation group (N = 359), the AUC was 0.87 (95% CI: 0.82-0.93) and 0.80 (95% CI: 0.74-0.87) for the nomogram and the Mayo criteria, respectively (P = 0.01). Calibration plots revealed the satisfactory performance of the nomogram. Decision curve analysis showed a positive net benefit of this nomogram, which indicated clinical value.

CONCLUSION

This model may promote risk stratification and individualized treatment, thus improving the prognosis.

Endometrial telomerase activity in women with either endometrial cancer or hyperplasia: A systematic review and meta-analysis

AIM

We performed a systematic review and meta-analysis to assess whether endometrial telomerase activity is associated with endometrial cancer or hyperplasia.

METHODS

PubMed, Web of Science, Embase, Scielo, LILAC, and CNKI databases were searched to obtain relevant literature for articles published through June 2022, following PRISMA guidelines and a registered PROSPERO protocol. We included observational studies reporting endometrial telomerase activity in patients with either endometrial cancer or hyperplasia compared with benign endometrial tissue (control women). The Newcastle-Ottawa Scale was used to evaluate the quality of studies. Data were expressed as the odds ratios (OR) and 95 % confidence intervals (CI). Random effects and inverse variance methods were used to meta-analyze associations. The I² test was used to assess heterogeneity.

RESULTS

There were significant associations between endometrial telomerase activity and either endometrial cancer (20 studies, OR = 10.65, 95 % CI 6.39, 17.75, p = 0.00001, I² = 21 %) or endometrial hyperplasia (nine studies, OR = 3.62, 95 % CI 1.61, 8.13, p = 0.002, I² = 36 %) compared to women without endometrial cancer and hyperplasia. There was not a significant difference in telomerase activity in women with endometrial cancer compared to those with endometrial hyperplasia (seven studies, OR = 1.03; 95 % CI 0.31, 3.37, p = 0.96, I² = 49 %). In subgroup analyses, there were no significant differences in telomerase activity in patients with endometrial cancer by type of observational studies and by countries of the studies.

CONCLUSION

Endometrial telomerase activity is higher in women with either endometrial cancer or endometrial hyperplasia compared to control women without those lesions.

Risk factors for endometrial cancer in Black women

PURPOSE

The incidence of endometrial cancer (EC) has been increasing faster among Black women than among other racial/ethnic groups in the United States. Although the mortality rate is nearly twice as high among Black than White women, there is a paucity of literature on risk factors for EC among Black women, particularly regarding menopausal hormone use and severe obesity.

METHODS

We pooled questionnaire data on 811 EC cases and 3,124 controls from eight studies with data on self-identified Black women (4 case-control and 4 cohort studies). We analyzed cohort studies as nested case-control studies with up to 4 controls selected per case. We used logistic regression to estimate multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

We observed a positive association between BMI and EC incidence (P_trend < 0.0001) The OR comparing BMI ≥ 40 vs. < 25 kg/m² was 3.92 (95% CI 2.91, 5.27). Abdominal obesity among those with BMI < 30 kg/m² was not appreciably associated with EC risk (OR 1.21, 95% CI 0.74, 1.99). Associations of reproductive history with EC were similar to those observed in studies of White women. Long-term use of estrogen-only menopausal hormones was associated with an increased risk of EC (≥ 5 years vs. never use: OR 2.08, 95% CI: 1.06, 4.06).

CONCLUSIONS

Our results suggest that the associations of established risk factors with EC are similar between Black and White women. Other explanations, such as differences in the prevalence of known risk factors or previously unidentified risk factors likely underlie the recent increases in EC incidence among Black women.

Statins as Repurposed Drugs in Gynecological Cancer: A Review

Discovering new drugs is an expensive and time-consuming process, including target identification, bioavailability, pharmacokinetic (PK) tests, pharmacodynamic (PD) tests, toxicity profiles, recommended dosage test, and observation of the side effects, etc. Repurposed drugs could bypass some steps, starting from phase II trials, and shorten the processes. Statins, also known as HMG-CoA inhibitors (HMGCR), are commonly used to manage and prevent various cardiovascular diseases and have been shown to improve the morbidity and mortality of patients. In addition to the inhibitory effects on the production of cholesterol, the beneficial effects of statins on the prognosis and risk of various cancers are also shown. Statins not only inhibited cell proliferation, metastasis, and chemoresistance but affected the tumor microenvironment (TME). Thus, statins have great potential to be repurposed in oncology. Hence, we review the meta-analysis, cohort, and case-control studies of statins in gynecological cancers, and elucidate how statins regulate cell proliferation, apoptosis, tumor growth, and metastasis. Although the results in gynecological cancers remain controversial and the effects of different statins in different histotypes of gynecological cancers and TME are needed to elucidate further, statins are excellent candidates and worthy of being repurposed drugs in treating gynecological cancers.

Synergism between the metabolic syndrome components and cancer incidence: results from a prospective nested case-control study based on the China Health and Retirement Longitudinal Study (CHARLS)

OBJECTIVES

Synergism between the metabolic syndrome (MetSyn) components and cancer incidence still remains inconclusive. We aimed to investigate the unique or joint role of MetSyn components in cancer onset.

DESIGN

We conducted a prospective nested case-control study based on the China Health and Retirement Longitudinal Study.

SETTING

An ongoing national representative longitudinal study included follow-up survey of people aged 45 years and older and their partners living in private households in China.

PARTICIPANTS

There were 17 708 individuals included at baseline. A total of 306 incident cancers was identified during the follow-up. For every case, we used incidence-density sampling to match three concurrent cancer-free controls by age, sex, and both duration and calendar time of follow-up. Exposure of interest was any MetSyn diagnosis at baseline.

RESULTS

We observed elevation in cancer risk associated with MetSyn in a significant way when the number of MetSyn components was over three (OR: 1.88; 95% CI: 1.19 to 2.97), or when components contained any of elevated triglycerides (OR: 1.61; 95% CI: 1.05 to 2.48), reduced high-density lipoprotein (HDL) cholesterol (OR: 2.33; 95% CI: 1.40 to 3.86) or elevated blood pressure (OR: 1.65; 95% CI: 1.04 to 2.59) after consistent multiple adjustments in different models. The highest cancer risk was in the female reproductive system and breast cancer (OR: 4.22; 95% CI: 1.62 to 10.95) followed by digestive system (OR: 1.67; 95% CI: 1.11 to 2.53). Sensitivity analyses showed similar results after first follow-up was excluded. However, any unique MetSyn component was not associated with increased cancer risk. Interestingly, the reduced HDL was observed to be widely associated with over twofold increased risk of cancer, only when together with other MetSyn components.

CONCLUSION

MetSyn components, in a collaborative manner rather than its unique component, were associated with elevated cancer risk. Not only obesity but even subtle metabolic disturbances may give rise to cancer.

Metabolic syndrome is an independent risk factor for time to complete remission of fertility-sparing treatment in atypical endometrial hyperplasia and early endometrial carcinoma patients

OBJECTIVE

Fertility-sparing treatment of atypical endometrial hyperplasia (AEH) and early endometrial carcinoma (EC) patients has recently emerged important social health topic. This study is designed to explore the risk factors for time to complete remission (CR) of fertility-sparing treatment in woman with AEH and early EC.

METHODS

A retrospective study was designed with clinical data from 106 patients admitted between January 2012 to December 2019. Univariate and multivariate logistic analysis were used to explore independent risk factors for time to CR. These factors were employed in receiver operator characteristic (ROC) curve and the decision curve analysis (DCA) to evaluate predictive accuracy of time to CR. Stratified analysis and interactive analysis was also performed for more in-depth perspective.

RESULTS

Univariate analysis showed that fasting blood glucose levels (FBG, OR = 1.6, 95%CI: 0.6-2.5, P = 0.020), metabolic syndrome (MetS, OR = 3.0, 95%CI: 1.1-5.0, P = 0.003), and polycystic ovary syndrome (PCOS, OR = 2.0, 95%CI: 0.5-3.4, P = 0.009) were associated with time to CR. Among these factors, multivariate analysis confirmed MetS (OR = 3.1, 95%CI: 1.0-5.2, P = 0.005) was an independent risk factor. The area under the ROC curve (AUC) of MetS was higher than FBG and PCOS (AUC = 0.723 vs 0.612 and 0.692). The AUC of FBG combined with PCOS was 0.779, and it was improved to 0.840 when MetS was included (P < 0.05). Additionally, MetS played different roles in time to CR in various groups. Moreover, we found high-density lipoprotein (HDL) and MetS had an interactive effect for time to CR.

CONCLUSION

MetS is an independent risk factor for time to CR and should be taken seriously in fertility-sparing management of AEH and early EC patients.

Metabolic Syndrome as a Risk Factor of Endometrial Cancer: A Nationwide Population-Based Cohort Study of 2.8 Million Women in South Korea

Background

A positive relationship was reported between metabolic syndrome and the risk of endometrial cancer. Studies on the relationship between metabolic syndrome and endometrial cancer have been mainly conducted in post-menopausal women. We aimed to investigate the risk of endometrial cancer according to metabolic syndrome and menopausal status using the Korean nationwide population-based cohort.

Methods

We enrolled 2,824,107 adults (endometrial cancer group; N = 5,604 and control group; N= 2,818,503) from the Korean National Health Insurance Service checkup database from January 1 to December 31, 2009. The median follow-up duration was 8.37 years. Metabolic syndrome was diagnosed as having at least three of the following five components: abdominal obesity, hypertriglyceridemia, low levels of high-density lipoprotein cholesterol, raised blood pressure, and hyperglycemia. Multivariate Cox proportional hazard models were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) to estimate endometrial cancer risk.

Results

The endometrial cancer risk was higher in the metabolic syndrome group than that in the non-metabolic syndrome group (HR, 1.362; 95% CI, 1.281–1.449). The association between metabolic syndrome and endometrial cancer risk was significant in the premenopausal subgroup (HR, 1.543; 95% CI, 1.39–1.713) and postmenopausal subgroup (HR, 1.306; 95% CI, 1.213–1.407). The incidence of endometrial cancer was more closely related to metabolic syndrome components in the pre-menopausal subgroup than those in the post-menopausal subgroup (for waist circumference, blood pressure, triglycerides and high-density lipoprotein cholesterol, all p for interaction <0.0001 respectively, and for fasting blood glucose, p for interaction 0.0188). The incidence of endometrial cancer positively correlated with the number of metabolic syndrome components (log-rank p <0.0001).

Conclusion

Our large population-based cohort study in Korean women suggests that metabolic syndrome and its accumulated components may be risk factors for endometrial cancer, particularly in the pre-menopausal women.

Antioxidative, Anti-Inflammatory, Anti-Obesogenic, and Antidiabetic Properties of Tea Polyphenols-The Positive Impact of Regular Tea Consumption as an Element of Prophylaxis and Pharmacotherapy Support in Endometrial Cancer

Endometrial cancer (EC) is second only to cervical carcinoma among the most commonly diagnosed malignant tumours of the female reproductive system. The available literature provides evidence for the involvement of 32 genes in the hereditary incidence of EC. The physiological markers of EC and coexisting diet-dependent maladies include antioxidative system disorders but also progressing inflammation; hence, the main forms of prophylaxis and pharmacotherapy ought to include a diet rich in substances aiding the organism’s response to this type of disorder, with a particular focus on ones suitable for lifelong consumption. Tea polyphenols satisfy those requirements due to their proven antioxidative, anti-inflammatory, anti-obesogenic, and antidiabetic properties. Practitioners ought to consider promoting tea consumption among individuals genetically predisposed for EC, particularly given its low cost, accessibility, confirmed health benefits, and above all, suitability for long-term consumption regardless of the patient’s age. The aim of this paper is to analyse the potential usability of tea as an element of prophylaxis and pharmacotherapy support in EC patients. The analysis is based on information available from worldwide literature published in the last 15 years.

Prognostic-Related Metabolic Score for Survival Prediction in Early-Stage Endometrioid Endometrial Cancer: A Multi-Center and Retrospective Study

Objective

Patients with endometrial cancer (EC) combined with metabolic syndrome (MetS) have a worse prognosis than those without MetS. This study aimed to investigate whether partial metabolic disorder significantly influenced early-stage endometrioid EC (EEC) survival and searched for a more efficient method to evaluate metabolic status.

Methods

This is a nationwide, multicenter cohort study that included 998 patients with primary early-stage EEC from 2001 to 2018. Patients were divided into different metabolic groups based on the diagnostic criteria of the Chinese Medical Association (CDC). The progression-free survival (PFS) time was compared between various metabolic status. Meanwhile, we established an EC Prognostic-Related Metabolic Score (ECPRM Score) to explore the association of the severity of metabolic status and early-stage EEC PFS. A nomogram was established for predicting PFS, which was externally validated in a testing set that includes 296 patients.

Results

A partial metabolic disorder, as well as MetS, was an independent risk factor of poor survival of patients with early-stage EEC [hazard ratio (HR) = 7.6, 95% CI = 1.01–57.5, p < 0.05]. A high ECPRM Score was associated with lower PFS (HR = 2.1, 95% CI = 1.05–4.0, p < 0.001). The nomogram, in which the ECPRM Score contributed most to the prognosis, exhibited excellent discrimination of survival supported by the internal and external validations. In addition, the calibration curve supports its robust predicting ability.

Conclusion

Even though they do not meet the criteria of MetS, partial metabolic disorders were also associated with adverse outcomes in early-stage EEC. The ECPRM Score is beneficial for clinicians to evaluate the severity of metabolic abnormalities and guide patients to ameliorate the poor prognosis of metabolic disorders.

Adult lifetime body mass index trajectories and endometrial cancer risk

OBJECTIVE

To identify body mass index (BMI) trajectories in adult life and to examine their association with endometrial cancer (EC) risk, also exploring whether relations differ by HRT use.

DESIGN

Pooled analysis of two case control studies.

SETTING

Italy and Switzerland.

POPULATION

A total of 458 EC cases and 782 controls.

METHODS

We performed a latent class growth model in order to identify homogenous BMI trajectories over 6 decades of age, with a polynomial function of age. Odds Ratios (ORs) and the corresponding 95% confidence intervals (CI) for EC risk were derived through a multiple logistic regression model, correcting for classification error.

MAIN OUTCOME MEASURES

The relation of BMI trajectories with endometrial cancer.

RESULTS

We identified 5 BMI trajectories. Compared with women in the 'Normal weight-stable' trajectory, a reduction by about 50% in the risk of EC emerged for those in the 'Underweight increasing to normal weight' (95% CI=0.28-0.99). The 'Normal weight increasing to overweight' and the 'Overweight-stable' trajectories were associated to, respectively, an excess of 3% (95% CI=0.66-1.60) and of 71% (95% CI= 1.12-2.59) in cancer risk. The OR associated to the trajectory 'Overweight increasing to obese' was 2.03 (95% CI= 1.31-3.13). Stronger effects emerged among HRT never users (OR= 2.19 for the 'Overweight-stable' trajectory and OR=2.49 for the 'Overweight increasing to obese' trajectory).

CONCLUSIONS

Our study suggests that longer exposure to overweight and obesity across lifetime is associated with an increased risk of endometrial cancer. Weight during adulthood also appears to play an important role.

Endometrial cancer

Although endometrial cancer management remains challenging, a deeper understanding of the genetic diversity as well as the drivers of the various pathogenic states of this disease has led to development of divergent management approaches in an effort to improve therapeutic precision in this complex malignancy. This comprehensive review provides an update on the epidemiology, pathophysiology, diagnosis and molecular classification, recent advancements in disease management, as well as important patient quality-of-life considerations and emerging developments in the rapidly evolving therapeutic landscape of endometrial cancers.

Adiposity and cancer: a Mendelian randomization analysis in the UK biobank

BACKGROUND

Observational and Mendelian randomization (MR) studies link obesity and cancer, but it remains unclear whether these depend upon related metabolic abnormalities.

METHODS

We used information from 321,472 participants in the UK biobank, including 30,561 cases of obesity-related cancer. We constructed three genetic instruments reflecting higher adiposity together with either "unfavourable" (82 SNPs), "favourable" (24 SNPs) or "neutral" metabolic profile (25 SNPs). We looked at associations with 14 types of cancer, previously suggested to be associated with obesity.

RESULTS

All genetic instruments had a strong association with BMI (p < 1 × 10^-300 for all). The instrument reflecting unfavourable adiposity was also associated with higher CRP, HbA1c and adverse lipid profile, while instrument reflecting metabolically favourable adiposity was associated with lower HbA1c and a favourable lipid profile. In MR-inverse-variance weighted analysis unfavourable adiposity was associated with an increased risk of non-hormonal cancers (OR = 1.22, 95% confidence interval [CI]:1.08, 1.38), but a lower risk of hormonal cancers (OR = 0.80, 95%CI: 0.72, 0.89). From individual cancers, MR analyses suggested causal increases in the risk of multiple myeloma (OR = 1.36, 95%CI: 1.09, 1.70) and endometrial cancer (OR = 1.77, 95%CI: 1.16, 2.68) by greater genetically instrumented unfavourable adiposity but lower risks of breast and prostate cancer (OR = 0.72, 95%CI: 0.61, 0.83 and OR = 0.81, 95%CI: 0.68, 0.97, respectively). Favourable or neutral adiposity were not associated with the odds of any individual cancer.

CONCLUSIONS

Higher adiposity associated with a higher risk of non-hormonal cancer but a lower risk of some hormone related cancers. Presence of metabolic abnormalities might aggravate the adverse effects of higher adiposity on cancer. Further studies are warranted to investigate whether interventions on adverse metabolic health may help to alleviate obesity-related cancer risk.

Glucose Activates Lysine-Specific Demethylase 1 through the KEAP1/p62 Pathway

Endometrial cancer incidence increases annually. Several risk factors, including high glucose intake, are associated with endometrial cancer. We investigated whether glucose affects lysine-specific demethylase 1 (LSD1) expression and the responsible molecular mechanisms. A high concentration of glucose stimulated p62 phosphorylation and increased LSD1 protein expression. Knockdown of p62 or treatment with mammalian target of rapamycin (mTOR), transforming growth factor-β activated kinase 1 (TAK1), casein kinase 1 (CK1), and protein kinase C (PKC) inhibitors abrogated glucose-regulated LSD1 expression. Unphosphorylated p62 and LSD1 formed a complex with Kelch-like ECH-associated protein 1 (KEAP1) and were degraded by the KEAP1-dependent proteasome. Phosphorylated p62 increased LSD1 protein expression by escaping the KEAP1 proteasome complex. LSD1 and KEAP1 interaction was enhanced in the presence of the nuclear factor erythroid 2-related factor 2 (NRF2) protein. LSD1 also participated in antioxidant gene regulation with NRF2. In diabetic mice, increasing LSD1and phospho-p62 expression was observed in uterine epithelial cells. Our results indicate that glucose induces p62 phosphorylation through mTOR, TAK1, CK1, and PKC kinases. Subsequently, phospho-p62 competitively interacts with KEAP1 and releases NRF2–LSD1 from the KEAP1 proteasome complex. Our findings may have public health implications for the prevention of endometrial cancer.

Diabetes Risk Reduction Diet and Endometrial Cancer Risk

Diabetes increases endometrial cancer risk. We investigated the role of a diabetes risk reduction diet (DRRD) on the risk of endometrial cancer using data from a multicentric, Italian hospital-based case-control study (1992-2006) enrolling 454 histologically confirmed cases of endometrial cancer and 908 controls matched by age and center. We derived a DRRD score assigning higher scores for higher intakes of cereal fiber, fruit, coffee, polyunsaturated:saturated fatty acid ratio, and nuts and for lower glycemic load and lower intakes of red/processed meat and sugar-sweetened beverages/fruit juices. The odds ratios (OR) of endometrial cancer according to the DRRD score were derived by multiple conditional logistic regression models. The OR for high (DRRD score >24, i.e., third tertile) versus medium-low adherence to the DRRD was 0.73 (95% confidence interval, CI, 0.55-0.97). Similar results were observed after the exclusion of diabetic women (OR 0.75; 95% CI, 0.56-1.00) and allowance for total vegetable consumption (OR 0.80; 95% CI, 0.60-1.07). Inverse associations were observed in most of the analyzed subgroups. The OR for high DRRD combined with high vegetable consumption was 0.45 (95% CI, 0.28-0.73). Our results suggest that diets able to reduce diabetes risk may also reduce endometrial cancer risk. High vegetable consumption combined with high adherence to the DRRD may provide additional benefit in endometrial cancer prevention.

The Influence of the Metabolic Syndrome on Early Postoperative Outcomes of Patients With Advanced-stage Endometrial Cancer

BACKGROUND/AIM

Endometrial cancer is one of the most commonly encountered malignancies among obese women worldwide, a strong causality relationship being established between the two entities. Furthermore, obesity is also associated with metabolic syndrome; the aim of this study was to investigate the effect of metabolic syndrome on the postoperative outcomes of patients with endometrial cancer.

PATIENTS AND METHODS

Data of 23 patients diagnosed with endometrial cancer and metabolic syndrome were retrospectively reviewed and compared to the those of a control group of patients diagnosed with endometrial cancer in the absence of metabolic syndrome.

RESULTS

Patients in the first group presented significantly higher values of body mass index when compared to the control group. There were no significant differences in terms of stage, histopathological subtype or degree of differentiation between the two groups. The completeness of cytoreduction was lower among patients with metabolic syndrome, however, this did not reach statistical significance (p=0.08). Although the rate of complete debulking was lower among those with metabolic syndrome, the rates of postoperative complications were significantly higher.

CONCLUSION

The association of metabolic syndrome significantly influences the risk of postoperative complications in patients with endometrial cancer; moreover, in certain cases, it might preclude the achievement of freedom from residual disease.

The effect of metabolic syndrome on head and neck cancer incidence risk: a population-based prospective cohort study

BACKGROUND

There are limited evidences clarifying the impact of metabolic syndrome (MS) and its components on head and neck cancer (HNC) incidence risk. We explored the correlation between MS, MS components, and the combined effects of MS and C-reactive protein (CRP) and HNC risk.

METHODS

This is a prospective analysis of 474,929 participants from the UK Biobank cohort. Cox proportional hazard regression was utilized to assess the hazard ratio (HR) and 95% confidence interval (CI) and to explore the non-linear correlation between an individual MS component and HNC risk.

RESULTS

Individuals with MS (HR, 1.05; 95%CI, 0.90-1.22) had no higher HNC risk than those without MS. More MS components showed no higher HNC risk. Nevertheless, hyperglycemia (HR, 1.22; 95%CI, 1.02-1.45) was independently correlated with elevated HNC risk. In a non-linear manner, waist circumference and high-density lipoprotein cholesterol (HDL-C) showed a U-shaped association with HNC risk. Further, piecewise linear model analysis indicated that higher male waist circumference, female waist circumference (≥93.16 cm), blood glucose (≥4.70 mmol/L) and male HDL-C (≥1.26mmo/L), and lower male HDL-C (<1.26mmo/L) were correlated with higher HNC risk. Increased CRP (≥1.00mg/dL) elevated HNC risk and individuals with MS and CRP≥1.00mg/dL had the highest HNC risk (HR, 1.29; 95%CI, 1.05-1.58). But no joint effect between MS and CRP was detected (p-interaction=0.501).

CONCLUSIONS

MS are not correlated with elevated HNC risk. High waist circumference and blood glucose are independent risk factor of HNC incidence. Controlling HDL-C in an appropriate range can get the lowest risk of male HNC. No joint effect of MS and CRP exists in HNC tumorigenesis.

Metabolic Syndrome and Risk of Upper Tract Urothelial Carcinoma: A Case-Control Study From Surveillance, Epidemiology and End Results-Medicare-Linked Database

Background

Metabolic syndrome (MetS) and its components are associated with increased risks of several cancers. However, the relationship between MetS and upper tract urothelial carcinoma (UTUC) has never been investigated before.

Methods

We identified 3,785 UTUC cases aged over 65 years old within the Surveillance, Epidemiology and End Results-Medicare database between 2007 and 2016. For comparison, non-cancer controls (n = 189,953) were selected from the 5% random sample of individuals residing within regions of SEER registries and matched with cases through diagnosis date and pseudo-diagnosis date. MetS and its components were all defined by using ICD-9-CM codes. Multivariate logistic regression models were conducted to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Time trends for MetS and its components were reported and we also performed dose-response effect analysis to test the concomitant effect of these components. The study was presented following the STROBE reporting checklist.

Results

UTUC risk was associated with metabolic syndrome (NCEP-III: OR: 1.669, 95% CI: 1.550–1.792; IDF: OR: 1.924, 95% CI: 1.676–2.172) and its component factors: elevated waist circumference/central adiposity (OR: 1.872, 95% CI: 1.693–2.055), impaired fasting glucose (OR: 1.306, 95% CI: 1.133–1.480), high blood pressure (OR: 1.295, 95% CI: 1.239–1.353), high triglycerides (OR: 1.280, 95% CI: 1.222–1.341), and low high-density lipoprotein cholesterol (OR: 1.354, 95% CI: 1.118–1.592). Consistent associations could also be observed in the subgroup analyses by tumor stages, grades, and tumor size. Additionally, the rates of MetS increased over time in both UTUC and control cohort (NCEP-III criterion; EAPC: +18.1%, P <0.001; EAPC: +16.1%, P <0.001, respectively). A significantly gradual increase in UTUC rates could be seen as the No. of the MetS components increase (χ² = 37.239, P_trend = 0.000).

Conclusions

Among people aged over 65, MetS and its components were significant risk factors for UTUC with consistent associations in different tumor stages, grades, and tumor size. Even if a subject who did not meet the criteria for MetS had only one of the components, he (she) still had an elevated risk for UTUC. Strategies to control the epidemic of MetS and its components might contribute to a reduction in the UTUC burden. The findings should be considered tentative until ascertained by more researches.

A single centre experience of metabolic syndrome and endometrial carcinoma: 5 years review

Endometrial cancer (EC) has been found to have a strong association with overweight and obesity. The aim of this study was to evaluate the link between metabolic syndrome and EC among patients. A total of 119 patients with histologically confirmed EC were recruited. About 102 cases of endometrioid carcinoma (Type I) and serous (n = 7), clear cell (n = 3) and carcinosarcoma (n = 7) were the Type II. Metabolic syndrome was significantly associated with increased risk of Type I EC (OR = 3.43, 95% CI = 1.12-10.46, p < .05) where obesity risk revealed as the main factor in Type I EC (OR = 3.88, 95% CI = 1.27-11.85, p < .05). There was no significant difference between both subtypes with other metabolic components and no impact on patients' overall survival and disease-free survival (p > .05). Metabolic syndrome was positively associated with an increased risk of Type I EC with obesity being the most influential risk factor.Impact statementWhat already known on this subject? Endometrial cancer (EC) is one of the most prevalent cancers worldwide and have a strong association with overweight and obesity of at least 40%, but there is conflicting evidence of an association of EC with metabolic syndrome (MS).What result of this study add? This study evaluated the link between EC and MS, such as high blood pressure, BMI, fasting blood sugar, triglyceride, Hyper Density Lipoprotein (HDL).What implications are of these findings for clinical practice & further research? Type I EC had and association with MS with obesity is the most potent risk factor. As the prevalence of metabolic syndrome is alarmingly high among adult Malaysians, the incidence of EC is projected to increase in the coming years. Proactive preventative measures and intervention essential for reducing the incidence of endometrial cancers. Future research to clarify the association between metabolic syndrome and endometrial cancer survival and to investigate other lifestyle factors that may affect the prognosis is needed.

Endometrial Cancer as a Metabolic Disease with Dysregulated PI3K Signaling: Shedding Light on Novel Therapeutic Strategies

Endometrial cancer (EC) is one of the most common malignancies of the female reproductive organs. The most characteristic feature of EC is the frequent association with metabolic disorders. However, the components of these disorders that are involved in carcinogenesis remain unclear. Accumulating epidemiological studies have clearly revealed that hyperinsulinemia, which accompanies these disorders, plays central roles in the development of EC via the insulin-phosphoinositide 3 kinase (PI3K) signaling pathway as a metabolic driver. Recent comprehensive genomic analyses showed that over 90% of ECs have genomic alterations in this pathway, resulting in enhanced insulin signaling and production of optimal tumor microenvironments (TMEs). Targeting PI3K signaling is therefore an attractive treatment strategy. Several clinical trials for recurrent or advanced ECs have been attempted using PI3K-serine/threonine kinase (AKT) inhibitors. However, these agents exhibited far lower efficacy than expected, possibly due to activation of alternative pathways that compensate for the PIK3-AKT pathway and allow tumor growth, or due to adaptive mechanisms including the insulin feedback pathway that limits the efficacy of agents. Overcoming these responses with careful management of insulin levels is key to successful treatment. Further interest in specific TMEs via the insulin PI3K-pathway in obese women will provide insight into not only novel therapeutic strategies but also preventive strategies against EC.

Association Between Metabolic Syndrome and Endometrial Cancer Survival in a SEER-Medicare Linked Database

BACKGROUND

Metabolic syndrome has previously been linked to increased risk of endometrial cancer. This study examines the association between metabolic syndrome and cancer-specific survival (CSS) in early stage and locoregionally advanced endometrial cancer.

METHODS

The SEER-Medicare linked database was used to identify a cohort of patients with endometrial cancer between 1992 and 2011 who underwent hysterectomy. Patients with incomplete stage or grade information were excluded. Patients were stratified into early stage (stage I to II) or locoregionally advanced (stage III to IVa) disease. Metabolic syndrome status was determined through Medicare claims 1 year before diagnosis. The relationship between metabolic syndrome and CSS was evaluated using univariable and multivariable Cox proportional hazards regression analyses.

RESULTS

A total of 10,090 patients with endometrial cancer were identified. The mean age was 75 and the majority (91.5%) were white. At diagnosis, 86.6% of patients were early stage and 13.4% were locoregionally advanced. Sixteen percent of patients had metabolic syndrome. On stage stratified multivariable analysis, race, income quartile, year of diagnosis, histopathology, and adjuvant treatment were associated with CSS in early stage disease. Presence of metabolic syndrome was associated with worse CSS in early stage disease (hazard ratio=1.28, 95% confidence interval: 1.09-1.53); this difference did not exist for locoregionally advanced disease (hazard ratio=1.18, 95% confidence interval: 0.93-1.49).

CONCLUSIONS

In elderly early stage endometrial cancer patients, metabolic syndrome is associated with worse CSS. Control of metabolic syndrome through lifestyle and pharmacologic therapies may improve cancer prognosis in this population.

Association between metabolic syndrome and endometrial cancer risk: a systematic review and meta-analysis of observational studies

Existing evidence has revealed inconsistent results on the association between metabolic syndrome (MetS) and endometrial cancer (EC) risk. Herein, we aim to better understand this association. Systematic searches of PubMed, EMBASE, and Web of Science through 12 December 2019 were conducted. Observational studies that provided risk estimates of MetS and EC risk were eligible. The quality of the included studies was judged based on the Newcastle–Ottawa scale. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Six studies, comprising 17,772 EC cases and 150,371 participants were included. MetS, diagnosed according to the criteria of the National Cholesterol Education Program—Third Adult Treatment Panel, was associated with an increased risk of EC (OR: 1.62; 95% CI = 1.26–2.07) with substantial heterogeneity (I² = 78.3%). Furthermore, we found that women with MetS, diagnosed according to the criteria of the International Diabetes Federation, had a significantly higher risk of EC compared to healthy controls (OR: 1.45; 95% CI = 1.16–1.81; I² = 64.6%). Our findings were generally consistent with the main results in the majority of prespecified subgroups, as well as in sensitivity analyses. In conclusion, MetS is associated with EC risk.

Detecting Endometrial Cancer by Blood Spectroscopy: A Diagnostic Cross-Sectional Study

Endometrial cancer is the sixth most common cancer in women, with a rising incidence worldwide. Current approaches for the diagnosis and screening of endometrial cancer are invasive, expensive or of moderate diagnostic accuracy, limiting their clinical utility. There is a need for cost-effective and minimally invasive approaches to facilitate the early detection and timely management of endometrial cancer. We analysed blood plasma samples in a cross-sectional diagnostic accuracy study of women with endometrial cancer (n = 342), its precursor lesion atypical hyperplasia (n = 68) and healthy controls (n = 242, total n = 652) using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy and machine learning algorithms. We show that blood-based infrared spectroscopy has the potential to detect endometrial cancer with 87% sensitivity and 78% specificity. Its accuracy is highest for Type I endometrial cancer, the most common subtype, and for atypical hyperplasia, with sensitivities of 91% and 100%, and specificities of 81% and 88%, respectively. Our large-cohort study shows that a simple blood test could enable the early detection of endometrial cancer of all stages in symptomatic women and provide the basis of a screening tool in high-risk groups. Such a test has the potential not only to differentially diagnose endometrial cancer but also to detect its precursor lesion atypical hyperplasia—the early recognition of which may allow fertility sparing management and cancer prevention.

Risk factors for endometrial carcinoma among postmenopausal women in Sri Lanka: a case control study

Background

Endometrial carcinoma burden is on the rise globally. The objective of this study was to determine the risk factors for endometrial carcinoma among postmenopausal women in Western province in Sri Lanka.

Methods

A case control study was conducted recruiting 83 incident cases of endometrial carcinoma and 332 unmatched hospital controls from all the secondary and tertiary care hospitals in the province using consecutive sampling technique. A case was defined as a postmenopausal woman who had been residing in the province for at least a period of 1 year, diagnosed to have endometrial carcinoma with histological confirmation within 3 months of the initiation of data collection of the study. Data were collected using validated interviewer administered questionnaire. Risk factor were identified through multiple logistic regression and results were expressed as adjusted odds ratios (AOR) and 95% confidence intervals (CI).

Results

The independent risk factors of endometrial carcinoma are having family history of any type of cancer among first degree relative (AOR = 12.6; 95% CI:5.14–30.9), generalized obesity (BMI ≥25 kg/m²) (AOR = 11.85; 95% CI:5.12–27.4), never conceived (AOR = 3.84; 95% CI:1.37–10.7), age at menarche ≤11 years (AOR = 4.07; 95% CI:1.16–14.2), age > 55 years (AOR = 4.69; 95% CI:2.16–10.2), monthly family income of ≤20,000 Rupees (AOR = 2.65; 95% CI:1.31–5.39), sub-optimal consumption of deep fried food (AOR = 0.17; 95% CI:0.06–0.46), and low level household activities (AOR = 2.82; 95% CI:1.34–5.92).

Conclusions

There were eight independent risk factors of endometrial carcinoma specific for Sri Lankan postmenopausal women identified. Some modifiable risk factors such as generalized obesity, sub-optimal dietary practices and low level physical activities need to be addressed at primary prevention level.

Association between blood pressure and risk of cancer development: a systematic review and meta-analysis of observational studies

With the exception of renal cell carcinoma, studies assessing the association between hypertension and other cancers are inconsistent. We conducted a meta-analysis to assess this evidence. We included observational studies investigating the association between any definition of hypertension or systolic and diastolic blood pressure and risk of any cancer, after searching PubMed until November 2017. We calculated summary relative risks (RR) and 95% confidence intervals (CI) using inverse-variance weighted random effects methods. A total of 148 eligible publications were identified out of 39,891 initially screened citations. Considering only evidence from 85 prospective studies, positive associations were observed between hypertension and kidney, colorectal and breast cancer. Positive associations between hypertension and risk of oesophageal adenocarcinoma and squamous cell carcinoma, liver and endometrial cancer were also observed, but the majority of studies did not perform comprehensive multivariable adjustments. Systolic and diastolic blood pressure were positively associated with risk of kidney cancer but not with other cancers. In addition to the previously well-described association between hypertension and risk of kidney cancer, the current meta-analysis suggested that hypertensive individuals may also be at higher risk of colorectal and breast cancer. However, careful interpretation is required as most meta-analyses included relatively small number of studies, several relative risks had weak or moderate magnitude and maybe affected by residual confounding.

Metabolic Syndrome in Endometrial Cancer Patients: Systematic Review

Large numbers of previously published studies show the importance of Metabolic syndrome (MetS) in the development of endometrial cancer (EC), the most common gynecologic malignancy in the United States. Defining the association between EC and MetS is complicated by inconsistencies among the MetS definitions used in EC. The aim of this study was to identify the MetS definition that is most practical for EC patients, as well as to estimate the prevalence of MetS using each definition in EC patients. A systematic literature search of PubMed and Embase was conducted to identify studies published between 1988 and 2018 and reporting the components of MetS in EC patients. Relevant studies were selected based on the presence of key MetS components, including central obesity, dyslipidemia, elevated blood pressure, and impaired glucose metabolism. Two independent reviewers extracted information from these articles. Our literature search has identified 400 articles, 8 of which were used for the final analyses. In this systematic review, the prevalence of MetS in EC patients varied based on the definition used, ranging from 6% for International Diabetes Federation (IDF) to 62% for Harmonized. IDF and Harmonized of MetS were the most practical definitions for women with EC. While our review included different approaches to diagnosing MetS and linking it to EC, we argue that there is a need for single and practical MetS definition criteria to improve diagnostics, decrease the inconsistencies across the future EC studies, and foster a cohesive understanding of the evidence regarding the association between MetS and EC.

Pretreatment triglycerides-to-high density lipoprotein cholesterol ratio in postmenopausal women with endometrial cancer

Raised triglycerides (TG) and reduced high density lipoprotein cholesterol (HDL-c) are components of metabolic syndrome. Both high TG and metabolic syndrome have been reported to be risk factors of endometrial cancer. Therefore, triglycerides-to-high density lipoprotein cholesterol ratio (TG/HDL-c ratio) may be a useful biological indicator in managing endometrial cancer. We aimed to explore the association between pretreatment TG/HDL-c ratio and endometrial cancer in postmenopausal women, and to evaluate its potential role in the disease. Pretreatment serum lipid profile and TG/HDL-c ratio were retrospectively analyzed for 167 postmenopausal women with endometrial cancer and 464 matched noncancer controls. Compared with controls, pretreatment TG/HDL-c ratio in endometrial cancer patients significantly elevated regardless of whether patients had diabetes or overweight/obesity (P < 0.05). Further analyses showed that pretreatment TG/HDL-c ratio increased significantly with advanced tumor stage. Interestingly, TG/HDL-c ratio of type I endometrial cancer patients was higher than those with type II endometrial cancer. A positive association was found between pretreatment TG/HDL-c ratio and tumor stage (adjusted r = 0.176, P = 0.027) in endometrial cancer group. Receiver operating characteristic curve analysis yielded the cut-off value of 1.52 for TG/HDL-c ratio to discriminate patients with cancer from controls (area under the curve, 0.689; sensitivity, 51.5%; specificity, 84.1%). Multivariate logistic regression model identified TG/HDL-c ratio ≥ 1.52 (odds ratio = 4.123; P < 0.001) as an independent predictor of endometrial cancer. TG/HDL-c ratio was positively associated with endometrial cancer clinical features, such as tumor stage and pathogenetic type. Accordingly, pretreatment TG/HDL-c ratio might be a potential marker for endometrial cancer.

Metabolic syndrome and risk of endometrial cancer in postmenopausal women: a prospective study

BACKGROUND

Obesity is a strong risk factor for endometrial cancer, but it is unclear whether metabolic syndrome (MetS) contributes to endometrial cancer risk over and above the contribution of obesity.

METHODS

We examined the association of MetS and its components with risk of endometrial cancer in a sub-cohort of 24,210 women enrolled in the Women's Health Initiative cohort study. Two variants of the National Cholesterol Education Program Adult Treatment Panel III definition of the MetS were used: one including and one excluding waist circumference (WC). Cox proportional hazards models were used to estimate the association of the study exposures with disease risk.

RESULTS

When WC was included in the definition, MetS showed an approximately two-fold increase in endometrial cancer risk (HR 2.20; 95% CI 1.61-3.02); however, when WC was excluded, MetS was no longer associated with risk. We also observed that women with hyperglycemia, dyslipidemia and hypertension, in combination, had almost a twofold increased risk of endometrial cancer, independent of WC (HR 1.94; 95% CI 1.09, 3.46). Glucose, and, in particular, WC and body mass index were also positively associated with risk.

CONCLUSIONS

Our findings suggest that MetS may predict risk of endometrial cancer independent of obesity among women with the remaining four Mets components.

Serum calcium is a novel parameter to assess metabolic syndrome in endometrial carcinoma

OBJECTIVES

To investigate the distribution of serum calcium and the relationship between serum calcium and serum metabolic parameters in endometrial carcinoma (EC) patients.

METHODS

Retrospective assessment of patients diagnosed with endometrial cancer from Peking University People's Hospital from 2004 to 2009. Clinical characteristics as well as pretreatment serum calcium, albumin, fasting plasma glucose (FPG), serum triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol (TC) value were extracted from patient records. Serum calcium was corrected for albumin. Unpaired t test and analysis of covariance were used to compare serum calcium among categorical variables. Simple correlation analyses and partial correlation analyses were used to assess the associations between serum calcium and continuous variables.

RESULTS

Two-hundred twenty patients were included in this study. After adjusting for confounders, postmenopausal patients had higher total serum calcium (p=0.002) and albumin-corrected serum calcium (p=0.012) than premenopausal patients, endometrioid endometrial carcinoma (EEC) patients had higher total serum calcium than non-endometrioid endometrial carcinoma (NEEC) patients (p=0.037). Significant positive correlations were found between total serum calcium and FPG (p=0.017), TG (p=0.043), HDL (p=0.042), LDL (p<0.001), and TC (p<0.001) after adjusting for multiple variables, and the corrected serum calcium showed no significant correlation with metabolic parameters.

CONCLUSION

Total serum calcium might be a more sensitive parameter for metabolic syndrome in endometrioid endometrial cancer patients than lipids.

Is there any relationship between benign endometrial pathologies and metabolic status?

The aim of this study was to assess the relation between benign endometrial pathologies (polyp and/or hyperplasia without atypia) and the metabolic status (insulin resistance and metabolic syndrome) of the patients. A total of 168 cases were enrolled in the study. The patients were classified according to the presence of benign endometrial pathologies and their menopausal status. Then, the subjects were evaluated according to the metabolic syndrome criteria and the presence of an insulin resistance. The insulin resistance levels of the cases were analysed by four different methods. Obesity and a waist circumference of greater than 88 cm were observed significantly more in the study group with endometrial pathologies (p = .005 and p < .001, respectively). It was also observed that a fasting blood glucose level of higher than 110 mg/dL increased the risk of developing endometrial polyps and/or hyperplasia without atypia by almost five folds (OR: 5.26, 95% CI: 1.25-22.12). Furthermore, an insulin resistance was found to be significantly high in the study group (p = .002). Based on the observed significant relationship between an insulin resistance and benign endometrial pathologies, it can be concluded that insulin resistance plays an important role in the development of benign endometrial pathologies. Impact Statement What is already known on this subject? Metabolic anomalies such as obesity, type 2 diabetes, hypertension and dyslipidaemia play an important role in abnormal endometrial proliferation. Also, these metabolic anomalies have been known as risk factors for type I endometrial cancer. What the results of this study add? A significant relationship between an insulin resistance and benign endometrial pathologies was observed. What the implications are of these findings for clinical practice and/or further research? Based on this finding, we concluded that an insulin resistance may play an important role in the development of benign endometrial pathologies. The prevention and the treatment of obesity as a key factor of developing an insulin resistance, may reduce not only the incidence of malignant endometrial pathologies, but also the incidence of benign pathologies and of a malignant transformation.

Obesity alters the uterine environment before pregnancy

Obesity is a metabolic disorder that predisposes to numerous diseases and has become a major global public health concern. Cafeteria diet (CAF) is the animal model used for the study of obesity that more closely reflects Western diet habits. Previously, we described that CAF administration for 60 days induces obesity in female rats and their fetuses develop macrosomia. Given that, in our model, rats are not genetically modified and that obese mothers were fed standard chow during pregnancy, the aim of the current study was to test the hypothesis that obesity alters the intrauterine environment prior to pregnancy, and this may explain the exacerbated fetal weight gain. We found that uteri from obese rats during the estrous phase developed insulin resistance through mechanisms that involve the induction of uterine hypoxia and the down-regulation of the insulin receptor gene. Moreover, uterine cell proliferation was induced by obesity concomitantly with the reduction in the uterine contractile response to a β2 AR agonist, salbutamol, and this may be consequence of the down-regulation in the uterine β2 AR expression. We conclude that CAF-induced obesity alters the uterine environment in rats during the estrous phase and may cause the fetal macrosomia previously described by us in obese animals. The lower sensitivity of the uterus to a relaxation stimulus (salbutamol) is not a minor fact given that for implantation to occur the uterus must be relaxed for embryo nidation. Thus, the alteration in the uterine quiescence may impair implantation and, consequently, the foregoing pregnancy.

The role of metabolic syndrome variant in the malignant tumors progression

Metabolic syndrome (MS) is one of the leading risk factors for the development of some common cancers (endometrial cancer, postmenopausal breast cancer, colorectal cancer). Currently, a drug-induced metabolic syndrome related with androgen deprivation therapy in patients with prostate cancer represents a serious medical problem. Not only MS, or its individual components, but MS variants with different levels of leptin, adiponectin, visfatin, resistin are associated with tumor invasion, metastasis and survival rates in patients with MS-associated malignancies.

Metformin as a Therapeutic Target in Endometrial Cancers

Endometrial cancer is the most common gynecologic malignancy in developed countries. Its increasing incidence is thought to be related in part to the rise of metabolic syndrome, which has been shown to be a risk factor for the development of hyperestrogenic and hyperinsulinemic states. This has consequently lead to an increase in other hormone-responsive cancers as well e.g., breast and ovarian cancer. The correlation between obesity, hyperglycemia, and endometrial cancer has highlighted the important role of metabolism in cancer establishment and persistence. Tumor-mediated reprogramming of the microenvironment and macroenvironment can range from induction of cytokines and growth factors to stimulation of surrounding stromal cells to produce energy-rich catabolites, fueling the growth, and survival of cancer cells. Such mechanisms raise the prospect of the metabolic microenvironment itself as a viable target for treatment of malignancies. Metformin is a biguanide drug that is a first-line treatment for type 2 diabetes that has beneficial effects on various markers of the metabolic syndrome. Many studies suggest that metformin shows potential as an adjuvant treatment for uterine and other cancers. Here, we review the evidence for metformin as a treatment for cancers of the endometrium. We discuss the available clinical data and the molecular mechanisms by which it may exert its effects, with a focus on how it may alter the tumor microenvironment. The pleiotropic effects of metformin on cellular energy production and usage as well as intercellular and hormone-based interactions make it a promising candidate for reprogramming of the cancer ecosystem. This, along with other treatments aimed at targeting tumor metabolic pathways, may lead to novel treatment strategies for endometrial cancer.

Assessing Information Needs Regarding Metabolic Syndrome Among Gynecological Cancer Survivors: A Concurrent Mixed Method

BACKGROUND

Cancer survivors have an increased risk of non-cancer-related deaths, particularly metabolic syndrome (MetS).

OBJECTIVE

We aimed to assess knowledge deficits regarding metabolism-related diseases among gynecological cancer survivors and the preferred source of health information.

METHODS

Using a mixed methods approach, 70 participants responded to a structured modified version of the MetS questionnaire. We conducted 28 semistructured interviews of gynecological cancer survivors with MetS. Responses were independently coded by 2 researchers, including MetS knowledge, behaviors for self-management, and preferred learning methods.

RESULTS

Metabolic syndrome was diagnosed in 17% of the participants. More than 50% of the participants wanted to learn about MetS and requested a consultation with healthcare providers, 70% reported that they had heard of MetS, and 61.4% reported that they had MetS-related knowledge (correct answer rate by MetS-related component, ~50%). The level of MetS-related knowledge was poor in both the quantitative and qualitative data. Most of the participants defined MetS-related self-management health behaviors as regular eating and exercise in their own words. Participants mostly wanted exercise management (29% of the participants), followed by dietary life management (27.4%), stress management (17.4%), weight management (13.7%), definition and diagnostic methods of MetS (9.1%), and smoking and drinking management (3.3%). Participants wished to use a handbook in small groups or receive counseling by healthcare providers.

CONCLUSION

We observed poor awareness and knowledge level and the need for information regarding MetS among gynecological cancer survivors.

IMPLICATIONS FOR PRACTICE

An educational handbook or counseling could effectively improve self-management of health-related behaviors.

Coffee and cancer risk: a summary overview

We reviewed available evidence on coffee drinking and the risk of all cancers and selected cancers updated to May 2016. Coffee consumption is not associated with overall cancer risk. A meta-analysis reported a pooled relative risk (RR) for an increment of 1 cup of coffee/day of 1.00 [95% confidence interval (CI): 0.99-1.01] for all cancers. Coffee drinking is associated with a reduced risk of liver cancer. A meta-analysis of cohort studies found an RR for an increment of consumption of 1 cup/day of 0.85 (95% CI: 0.81-0.90) for liver cancer and a favorable effect on liver enzymes and cirrhosis. Another meta-analysis showed an inverse relation for endometrial cancer risk, with an RR of 0.92 (95% CI: 0.88-0.96) for an increment of 1 cup/day. A possible decreased risk was found in some studies for oral/pharyngeal cancer and for advanced prostate cancer. Although data are mixed, overall, there seems to be some favorable effect of coffee drinking on colorectal cancer in case-control studies, in the absence of a consistent relation in cohort studies. For bladder cancer, the results are not consistent; however, any possible direct association is not dose and duration related, and might depend on a residual confounding effect of smoking. A few studies suggest an increased risk of childhood leukemia after maternal coffee drinking during pregnancy, but data are limited and inconsistent. Although the results of studies are mixed, the overall evidence suggests no association of coffee intake with cancers of the stomach, pancreas, lung, breast, ovary, and prostate overall. Data are limited, with RR close to unity for other neoplasms, including those of the esophagus, small intestine, gallbladder and biliary tract, skin, kidney, brain, thyroid, as well as for soft tissue sarcoma and lymphohematopoietic cancer.

Effect of metformin use on the risk and prognosis of endometrial cancer: a systematic review and meta-analysis

BACKGROUND

Previous studies have suggested that metformin may be useful for preventing and treating endometrial cancer (EC), while the results have been inconsistent. This systematic review and meta-analysis aimed to investigate the association between metformin use and risk and prognosis of patients with EC.

METHODS

PubMed, Embase, and the Cochrane Library databases were searched for observational studies evaluating the effect of metformin on EC prevention or treatment. The odds ratio (OR) was used for analyzing risks, and the hazard ratio (HR) was used for analyzing survival outcomes. A random-effects model was used for data analysis.

RESULTS

Seven studies reported data on EC risk. The pooled results suggested that metformin was not significantly associated with a lower risk of EC [OR = 1.05, 95% confidence interval (CI) 0.82-1.35, P = 0.70]. For patients with diabetes, metformin showed no advantage in reducing the EC risk compared with other interventions (OR = 0.99, 95% CI 0.78-1.26, P = 0.95). Further, seven studies were included for survival analysis. The pooled data showed that metformin could significantly improve the overall survival of patients with EC (HR = 0.61, 95% CI 0.48-0.77, P < 0.05) and reduce the risk of EC recurrence (OR = 0.50, 95% CI 0.28-0.92, P < 0.05) Finally, we noted metformin was associated with significantly improving the overall survival of EC patients among diabetes (HR = 0.47; 95%CI 0.33-0.67, P < 0.05).

CONCLUSIONS

This meta-analysis did not prove that metformin was beneficial for preventing EC. However, metformin could prolong the overall survival of patients with EC and reduce their risk of cancer relapse.

Molecular targets for the therapy of cancer associated with metabolic syndrome (transcription and growth factors)

Metabolic syndrome (MS) is one of the leading risk factors for the development of cardiovascular diseases, type II diabetes mellitus and reproductive system diseases. Currently, not only cardiovascular disease and reproductive history risks related with MS are frequently discussed, but it has been also shown that MS is associated with increased risk of some common cancers (endometrial cancer, postmenopausal breast cancer, colorectal cancer, biliary tract cancers and liver cancer for men). Further studies are required to understand the mechanisms of the involvement of MS components in the pathogenesis of malignant neoplasms. Changes in the expression of transcription and growth factors in the peripheral tissues as well as in cancer tissues of patients with MS were revealed. Transcription factors (AMP-activated protein kinase-1, STAT3, sterol regulatory element-binding protein-1 and peroxisome proliferator-activated receptor-γ), leptin and adiponectin receptors seem to be the most promising molecular targets for the therapy of cancers associated with MS.

Metformin for endometrial hyperplasia

BACKGROUND

Endometrial cancer is one of the most common gynaecological cancers in the world. Rates of endometrial cancer are rising, in part because of rising obesity rates. Endometrial hyperplasia is a precancerous condition in women that can lead to endometrial cancer if left untreated. Endometrial hyperplasia occurs more commonly than endometrial cancer. Progesterone tablets currently used to treat women with endometrial hyperplasia are associated with adverse effects in up to 84% of women. The levonorgestrel intrauterine device (Mirena Coil, Bayer HealthCare Pharmaceuticals, Inc., Whippany, NJ, USA) may improve compliance, but it is invasive, is not acceptable to all women, and is associated with irregular vaginal bleeding in 82% of cases. Therefore, an alternative treatment for women with endometrial hyperplasia is needed. Metformin, a drug that is often used to treat people with diabetes, has been shown in some human studies to reverse endometrial hyperplasia. However, the effectiveness and safety of metformin for treatment of endometrial hyperplasia remain uncertain.

OBJECTIVES

To determine the effectiveness and safety of metformin in treating women with endometrial hyperplasia.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed, Google Scholar, OpenGrey, Latin American Caribbean Health Sciences Literature (LILACS), and two trials registers from inception to 10 January 2017. We searched the bibliographies of all included studies and reviews on this topic. We also handsearched the conference abstracts of the European Society of Human Reproduction and Embryology (ESHRE) 2015 and the American Society for Reproductive Medicine (ASRM) 2015.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cross-over trials comparing metformin (used alone or in combination with other medical therapies) versus placebo or no treatment, any conventional medical treatment, or any other active intervention for women with histologically confirmed endometrial hyperplasia of any type.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility, extracted data from included studies, and assessed the risk of bias of included studies. We resolved disagreements by discussion or by deferment to a third review author. When study details were missing, review authors contacted study authors. The primary outcome of this review was regression of endometrial hyperplasia histology (with or without atypia) towards normal histology. Secondary outcome measures included recurrence of endometrial hyperplasia, progression of endometrial hyperplasia to endometrial cancer, hysterectomy rate, abnormal uterine bleeding, health-related quality of life, and adverse effects during treatment.

MAIN RESULTS

We included three RCTs in which a total of 77 women took part. We rated the quality of the evidence as very low for all outcomes owing to very serious risk of bias (associated with poor reporting, attrition, and limitations in study design) and imprecision.We performed a meta-analysis of two trials with 59 participants. When metformin was compared with megestrol acetate in women with endometrial hyperplasia, we found insufficient evidence to determine whether there were differences between groups for the following outcomes: regression of endometrial hyperplasia histology towards normal histology (odds ratio (OR) 3.34, 95% confidence interval (CI) 0.97 to 11.57, two RCTs, n = 59, very low-quality evidence), hysterectomy rates (OR 0.91, 95% CI 0.05 to 15.52, two RCTs, n = 59, very low-quality evidence), and rates of abnormal uterine bleeding (OR 0.91, 95% CI 0.05 to 15.52, two RCTs, n = 44 , very low-quality evidence). We found no data for recurrence of endometrial hyperplasia or health-related quality of life. Both studies (n = 59) provided data on progression of endometrial hyperplasia to endometrial cancer as well as one (n = 16) reporting some adverse effects in the metformin arm, notably nausea, thrombosis, lactic acidosis, abnormal liver and renal function among others.Another trial including 16 participants compared metformin plus megestrol acetate versus megestrol acetate alone in women with endometrial hyperplasia. We found insufficient evidence to determine whether there were differences between groups for the following outcomes: regression of endometrial hyperplasia histology towards normal histology (OR 9.00, 95% CI 0.94 to 86.52, one RCT, n = 16, very low-quality evidence), recurrence of endometrial hyperplasia among women who achieve regression (OR not estimable, no events recorded, one RCT, n = 8, very low-quality evidence), progression of endometrial hyperplasia to endometrial cancer (OR not estimable, no events recorded, one RCT, n = 13, very low-quality evidence), or hysterectomy rates (OR 0.29, 95% CI 0.01 to 8.37, one RCT, n = 16, very low-quality evidence). Investigators provided no data on abnormal uterine bleeding or health-related quality of life. In terms of adverse effects, three of eight participants (37.5%) in the metformin plus megestrol acetate study arm reported nausea.

AUTHORS' CONCLUSIONS

At present, evidence is insufficient to support or refute the use of metformin alone or in combination with standard therapy - specifically, megestrol acetate - versus megestrol acetate alone, for treatment of endometrial hyperplasia. Robustly designed and adequately powered randomised controlled trials yielding long-term outcome data are needed to address this clinical question.