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.

Real-World Practice Patterns and Predictors of Continuous versus Intermittent Androgen Deprivation Therapy Use for Prostate Cancer in Older Men

PURPOSE

Phase-III randomized control trial evidence suggests intermittent androgen deprivation therapy (IADT) is not significantly inferior to continuous androgen deprivation therapy (ADT) for patients with prostate cancer (PC). However, clinical practice and guidelines differ in their recommendations. We evaluate real-world utilization and practice patterns of IADT.

MATERIALS AND METHODS

Ontario men ≥65 years of age with PC who initiated ADT for ≥3 months were identified (1997-2017). Lapses in ADT ≥6 months (initial gap) and ≥3 months (subsequent gaps) were used to classify IADT. Neoadjuvant/adjuvant therapy was excluded. Disease stage adjustment was completed for patients with likely metastatic disease based on de novo presentation with ADT. Patient and physician predictors of IADT were analyzed using multivariable logistic regression.

RESULTS

We identified 8,544 patients with 1,715 having previously received local therapy. Among all patients, 16.4% received IADT. This ranged from 11.4%-24.8% across health-planning regions and increased to 26.6% in those with previous local therapy. Mean followup was 8.3 years. Patients with prior local therapy (OR 1.85, 95% CI 1.59-2.17, p <0.001) and those in the highest income quintile (OR 1.32, 95% CI 1.08-1.60, p=0.005) had increased odds of receiving IADT. Radiation oncologists were more likely to use IADT than urologists (OR 1.99, 95% CI 1.59-2.50, p <0.001), as were physicians with more experience (≥10 years in practice: OR 1.44, 95% CI 1.11-1.88, p=0.007). In specialty-stratified analyses, case volume was significantly associated with IADT for radiation oncologists (highest quartile: OR 1.73, 95% CI 1.14-2.62, p=0.009).

CONCLUSIONS

IADT remains underutilized for patients with PC who ≥65 years of age with only 1 in 4 to 1 in 6 eligible patients receiving this form of care. Clinical, sociodemographic and physician characteristics play an important role in treatment selection.

Abiraterone acetate in combination with androgen deprivation therapy compared to androgen deprivation therapy only for metastatic hormone-sensitive prostate cancer

BACKGROUND

Systemic androgen deprivation therapy (ADT), also referred to as hormone therapy,àhas long been the primary treatment for metastatic prostate cancer. Additional agents have been reserved for the castrate-resistant disease stage when ADT start becoming less effective. Abiraterone is an agent with an established role in that disease stage, which has only recently been evaluated in the hormone-sensitive setting.

OBJECTIVES

To assess the effects of early abiraterone acetate, in combination with systemic ADT, for newly diagnosed metastatic hormone-sensitive prostate cancer.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, six other databases, two trials registries, grey literature, and conference proceedings, up to 15 May 2020. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized trials, in which men diagnosed with hormone-sensitive prostate cancer were administered abiraterone acetate and prednisolone with ADT or ADTàalone.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data from the included studies. We performed statistical analyses using a random-effects model. We rated the quality of evidence according to the GRADE approach.

MAIN RESULTS

The search identified two randomized controlled trials (RCT), with 2201 men, who were assigned to receive either abiraterone acetate 1000 mg once daily and low dose prednisone (5mg) in addition to ADT, or ADT alone. In the LATITUDE trial, the median age and range of men in the intervention group was 68 (38 to 89) years, and 67 (33 to 92) years in the control group. Nearly all of the men in thisàstudy (97.6%) had prostate cancer with a Gleason score of at least 8 (ISUP grade group 4). Primary outcomes The addition of abiraterone acetate to ADT reduces the probability of death from any cause compared to ADT alone (hazard ratio [HR] 0.64, 95% confidence interval [CI] 0.56 to 0.73; 2 RCTs, 2201 men; high certainty of evidence); this corresponds to 163 fewer deaths per 1000 men with hormone-sensitive metastaticàprostate cancerà(210 fewer to 115 fewer) at five years. Abiraterone acetate in addition to ADT probably results in little to no differenceàin quality of life compared to ADT alone, measured with the Functional Assessment of Cancer Therapy-prostate total score (FACT-P; range 0 to 156; higher values indicates better quality of life),àat 12 months (mean difference [MD] 2.90 points, 95% CI 0.11 to 5.60; 1 RCT, 838 men; moderate certainty of evidence). Secondary outcomes Abiraterone plus ADT increases the risk of grades III to V adverse events compared to ADT alone (risk ratio [RR] 1.34, 95% CI 1.22 to 1.47; 1 RCT, 1199 men; high certainty of evidence); this corresponds to 162 more grade III to Vàevents per 1000 men with hormone-sensitive metastaticàprostate cancerà(105 more to 224 more) at a median follow-up of 30àmonths. Abiraterone acetate in addition to ADT probably reduces the probability of death due to prostate cancer compared to ADT alone (HR 0.58, 95% CI 0.50 to 0.68; 2 RCTs, 2201 men; moderate certainty of evidence). This corresponds to 120 fewer death from prostate cancer per 1000 men with hormone-sensitive metastaticàprostate cancerà(95% CI 145 fewer to 90 fewer) afteràa median follow-up of 30 months. The addition of abiraterone acetate to ADT probably decreases the probability of disease progression compared to ADT alone (HR 0.35, 95%CI 0.26 to 0.49; 2 RCTs, 2097 men; moderate certainty of evidence). This corresponds to 369 fewer incidences of disease progression per 1000 men with hormone-sensitive metastaticàprostate cancerà(456 fewer to 256 fewer)àafter a median follow-up of 30 months. The addition of abiraterone acetate to ADT probably increases the risk of discontinuing treatment due to adverse events compared to ADT alone (RR 1.50, 95% CI 1.17 to 1.92; 1 RCT, 1199 men; moderate certainty of evidence). This corresponds to 51 more men (95% CI 17 more to 93 more) discontinuing treatment because of adverse events per 1000 men treated with abiraterone acetate and ADT compared to ADT alone afteràa median follow-up of 30 months.

AUTHORS' CONCLUSIONS

The addition of abiraterone acetate to androgen deprivation therapy improves overall survival but probably not quality of life. Itàprobably also extends disease-specific survival, and delays disease progression compared to androgen deprivation therapy alone. However, the risk of grades III to V adverse events is increased, and probably, so is the risk of discontinuing treatment due to adverse events.

Epididymal Sparing Bilateral Simple Orchiectomy: Cost-Effectiveness and Aesthetic Preservation for Men with Metastatic Prostate Cancer

INTRODUCTION

In the last 2 decades medical androgen deprivation therapy has replaced surgical castration for the treatment of metastatic prostate cancer. We assessed costs and patient satisfaction associated with epididymal sparing bilateral simple orchiectomy in an underinsured, immigrant population.

METHODS

We performed epididymal sparing bilateral simple orchiectomy in patients with metastatic prostate cancer between January 2003 and September 2014 at our institution. Procedures were performed in the operating room with the patient under general anesthesia and later under conscious sedation. Associated material and facility costs were calculated and compared to costs of androgen deprivation therapy with leuprolide or degarelix. Medication costs were calculated using wholesale acquisition costs. Patient satisfaction and body image perception were evaluated using a survey questionnaire.

RESULTS

A total of 108 orchiectomies were performed in the operating room and 12 in the outpatient unit. The total cost of bilateral simple orchiectomy in the operating room was $4,118. By performing orchiectomy in the outpatient unit we reduced the cost to $2,101. The cost of orchiectomy in the operating room is the equivalent of 4 months of leuprolide and 7.8 months of degarelix. When performed in the outpatient clinic the cost of bilateral simple orchiectomy is equivalent to 2.1 months of leuprolide and 4 months of degarelix. Overall 95% of participants surveyed were pleased with the surgical results.

CONCLUSIONS

The average life expectancy of men with metastatic prostate cancer is 30 months and, thus, a onetime surgical cost offers significant cost savings. Further cost reductions are achieved by performing bilateral simple orchiectomy in the outpatient setting. By sparing the epididymis, patients are left with a sense of testicular preservation. Epididymal sparing bilateral simple orchiectomy is a cost-effective and cosmetically acceptable method of androgen deprivation therapy for patients with metastatic prostate cancer.

Non-steroidal antiandrogen monotherapy compared with luteinising hormone-releasing hormone agonists or surgical castration monotherapy for advanced prostate cancer

BACKGROUND

Non-steroidal antiandrogens and castration are the main therapy options for advanced stages of prostate cancer. However, debate regarding the value of these treatment options continues.

OBJECTIVES

To assess the effects of non-steroidal antiandrogen monotherapy compared with luteinising hormone-releasing hormone agonists or surgical castration monotherapy for treating advanced stages of prostate cancer.

SEARCH METHODS

We searched the Cochrane Prostatic Diseases and Urologic Cancers Group Specialized Register (PROSTATE), the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Web of Science with Conference Proceedings, three trial registries and abstracts from three major conferences to 23 December 2013, together with reference lists, and contacted selected experts in the field and manufacturers.

SELECTION CRITERIA

We included randomised controlled trials comparing non-steroidal antiandrogen monotherapy with medical or surgical castration monotherapy for men in advanced stages of prostate cancer.

DATA COLLECTION AND ANALYSIS

One review author screened all titles and abstracts; only citations that were clearly irrelevant were excluded at this stage. Then, two review authors independently examined full-text reports, identified relevant studies, assessed the eligibility of studies for inclusion, assessed trial quality and extracted data. We contacted the study authors to request additional information. We used Review Manager 5 for data synthesis and used the fixed-effect model for heterogeneity less than 50%; we used the random-effects model for substantial or considerable heterogeneity.

MAIN RESULTS

Eleven studies involving 3060 randomly assigned participants were included in this review. The quality of evidence is hampered by risk of bias. Use of non-steroidal antiandrogens decreased overall survival (hazard ratio (HR) 1.24, 95% confidence interval (CI) 1.05 to 1.48, six studies, 2712 participants) and increased clinical progression (one year: risk ratio (RR) 1.25, 95% CI 1.08 to 1.45, five studies, 2067 participants; 70 weeks: RR 1.26, 95% CI 1.08 to 1.45, six studies, 2373 participants; two years: RR 1.14, 95% CI 1.04 to 1.25, three studies, 1336 participants), as well as treatment failure (one year: RR 1.19, 95% CI 1.02 to 1.38, four studies, 1539 participants; 70 weeks: RR 1.27, 95% CI 1.05 to 1.52, five studies, 1845 participants; two years: RR 1.14, 95% CI 1.05 to 1.24, two studies, 808 participants), compared with medical or surgical castration. The quality of evidence for overall survival, clinical progression and treatment failure was rated as moderate according to GRADE. Predefined subgroup analyses showed that use of non-steroidal antiandrogens, compared with castration, was less favourable for overall survival, clinical progression (at one year, 70 weeks, two years) and treatment failure (at one year, 70 weeks, two years) in men with metastatic disease. Use of non-steroidal antiandrogens also increased the risk for treatment discontinuation due to adverse events (RR 1.82, 95% CI 1.13 to 2.94, eight studies, 1559 participants), including events such as breast pain (RR 22.97, 95% CI 14.79 to 35.67, eight studies, 2670 participants), gynaecomastia (RR 8.43, 95% CI 3.19 to 22.28, nine studies, 2774 participants) and asthenia (RR 1.77, 95% CI 1.36 to 2.31, five studies, 2073 participants). The risk of other adverse events, such as hot flashes (RR 0.23, 95% CI 0.19 to 0.27, nine studies, 2774 participants), haemorrhage (RR 0.07, 95% CI 0.01 to 0.54, two studies, 546 participants), nocturia (RR 0.38, 95% CI 0.20 to 0.69, one study, 480 participants), fatigue (RR 0.52, 95% CI 0.31 to 0.88, one study, 51 participants), loss of sexual interest (RR 0.50, 95% CI 0.30 to 0.83, one study, 51 participants) and urinary frequency (RR 0.22, 95% CI 0.11 to 0.47, one study, 480 participants) was decreased when non-steroidal antiandrogens were used. The quality of evidence for breast pain, gynaecomastia and hot flashes was rated as moderate according to GRADE. The effects of non-steroidal antiandrogens on cancer-specific survival and biochemical progression remained unclear.

AUTHORS' CONCLUSIONS

Currently available evidence suggests that use of non-steroidal antiandrogen monotherapy compared with medical or surgical castration monotherapy for advanced prostate cancer is less effective in terms of overall survival, clinical progression, treatment failure and treatment discontinuation due to adverse events. Evidence quality was rated as moderate according to GRADE. Further research is likely to have an important impact on results for patients with advanced but non-metastatic prostate cancer treated with non-steroidal antiandrogen monotherapy. However, we believe that research is likely not necessary on non-steroidal antiandrogen monotherapy for men with metastatic prostate cancer. Only high-quality, randomised controlled trials with long-term follow-up should be conducted. If further research is planned to investigate biochemical progression, studies with standardised follow-up schedules using measurements of prostate-specific antigen based on current guidelines should be conducted.

WITHDRAWN: Ovarian ablation for early breast cancer

BACKGROUND

Among women with early breast cancer, the effects of ovarian ablation on recurrence and death have been assessed by several randomised trials that now have long follow-up.

OBJECTIVES

In this report, the Early Breast Cancer Trialists' Collaborative Group present their third 5-yearly systematic overview (meta-analysis), now with 15 years' follow-up.

SEARCH STRATEGY

Trial identification procedures for the EBCTCG overviews have been described elsewhere. See under "EBCTCG" in the Breast Cancer Collaborative Review Group module.

SELECTION CRITERIA

All properly randomised trials that began recruiting before 1990 which compared the ablation or suppression of ovarian function, sometimes with the addition of prednisone, versus no such adjuvant treatment for women with operable breast cancer. In practice, all the trials that can be reviewed here began before 1980, and all involved surgical or therapeutic ablation.

DATA COLLECTION AND ANALYSIS

In 1995, information was sought on each patient in any randomised trial of ovarian ablation or suppression versus control that began before 1990. Data were obtained for 12 of the 13 studies that assessed ovarian ablation by irradiation or surgery, all of which began before 1980, but not for the four studies that assessed ovarian suppression by drugs, all of which began after 1985. Menopausal status was not consistently defined across trials; therefore, the main analyses are limited to women aged under 50 (rather than "premenopausal") when randomised. Oestrogen receptors were measured only in the trials of ablation plus cytotoxic chemotherapy versus the same chemotherapy alone.

MAIN RESULTS

Among 2102 women aged under 50 when randomised, most of whom would have been premenopausal at diagnosis, 1130 deaths and an additional 153 recurrences were reported. 15-year survival was highly significantly improved among those allocated ovarian ablation (52.4 vs 46.1%, 6.3 [SD 2.3] fewer deaths per 100 women, logrank 2p=0.001), as was recurrence-free survival (45.0 vs 39.0%, 2p=0.0007). The numbers of events were too small for any subgroup analyses to be reliable. The benefit was, however, significant both for those with ("node positive") and for those without ("node negative") axillary spread when diagnosed. In the trials of ablation plus cytotoxic chemotherapy versus the same chemotherapy alone, the benefit appeared smaller (even for women with oestrogen receptors detected on the primary tumour) than in the trials in the absence of chemotherapy (where the observed survival improvements were about six per 100 node-negative women and 12 per 100 node-positive women). Among 1354 women aged 50 or over when randomised, most of whom would have been perimenopausal or postmenopausal, there was only a non-significant improvement in survival and recurrence-free survival.

AUTHORS' CONCLUSIONS

In women aged under 50 with early breast cancer, ablation of functioning ovaries significantly improves long-term survival, at least in the absence of chemotherapy. Further randomised evidence is needed on the additional effects of ovarian ablation in the presence of other adjuvant treatments, and to assess the relevance of hormone-receptor measurements.

Advanced prostate cancer: an update

A number of therapeutic options are available or on the horizon for patients for whom initial treatment of localized prostate cancer has failed. Currently under study are time of therapy, maximum androgen blockade, and palliative and adjunctive therapies.