Early versus deferred standard androgen suppression therapy for advanced hormone-sensitive prostate cancer

BACKGROUND

Standard androgen suppression therapy (AST) using surgical or medical castration is considered a mainstay of advanced hormone-sensitive prostate cancer treatment. AST can be initiated early when disease is asymptomatic or deferred when patients suffer symptoms of disseminated prostate cancer.

OBJECTIVES

To assess the effects of early versus deferred standard AST for advanced hormone-sensitive prostate cancer.

SEARCH METHODS

For this Cochrane Review update, we performed a comprehensive search of multiple databases (CENTRAL, MEDLINE, Embase, Web of Science; last searched November 2018) and two clinical trial registers, with no restrictions on the language of publication or publication status. We also searched bibliographies of included studies and conference proceedings (last searched January 2019).

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) with a direct comparison of early versus deferred standard AST. We excluded all other study designs. Participants included had advanced hormone-sensitive prostate cancer receiving surgical or medical castration.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data. The primary outcomes were time to death of any cause and serious adverse events. Secondary outcomes were time to disease progression, time to death from prostate cancer, adverse events and quality of life. We performed statistical analyses using a random-effects model and assessed the certainty of evidence according to GRADE. We performed subgroup analyses for advanced but non-metastatic disease (T2-4/N+ M0), metastatic disease (M1), and prostate-specific antigen (PSA) relapse.

MAIN RESULTS

We identified seven new RCTs since publication of the original review in 2002. In total, we included 10 RCTs.Primary outcomesEarly AST probably reduces the risk of death from any cause over time (hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.75 to 0.90; moderate-certainty evidence; 4767 participants). This corresponds to 57 fewer deaths (95% CI 80 fewer to 31 fewer) per 1000 participants at 5 years for the moderate risk group and 23 fewer deaths (95% CI 32 fewer to 13 fewer) per 1000 participants at 5 years in the low risk group. We downgraded for study limitations. Early versus deferred AST may have little or no effect on serious adverse events (risk ratio (RR) 1.05, 95% CI 0.95 to 1.16; low-certainty evidence; 10,575 participants) which corresponds to 6 more serious adverse events (6 fewer to 18 more) per 1000 participants. We downgraded the certainty of evidence for study limitations and selective reporting.Secondary outcomesEarly AST probably reduces the risk of death from prostate cancer over time (HR 0.69, 95% CI 0.57 to 0.84; moderate-certainty evidence). This corresponds to 62 fewer prostate cancer deaths per 1000 (95% CI 87 fewer to 31 fewer) at 5 years for the moderate risk group and 24 fewer death from prostate cancer (95% CI 34 fewer to 12 fewer) per 1000 men at 5 years in the low risk group. We downgraded the certainty of evidence for study limitations.Early AST may decrease the rate of skeletal events (RR 0.37, 95% CI 0.17 to 0.80; low-certainty evidence) corresponding to 23 fewer skeletal events per 1000 (95% CI 31 fewer to 7 fewer). We downgraded for study limitations and imprecision. It may also increase fatigue (RR 1.41, 95% CI 1.23 to 1.62; low-certainty evidence), corresponding to 31 more men with this complaint per 1000 (95% CI 18 more to 48 more). We downgraded for study limitations and imprecision. It may increase the risk of heart failure (RR 1.90, 95% CI 1.09 to 3.33; low-certainty evidence) corresponding to 27 more events per 1000 (95% CI 3 more to 69 more). We downgraded the certainty of evidence for study limitations and imprecision.Global quality of life is probably similar after two years as assessed with the EORTC QLQ-C30 (version 3.0) questionnaire (mean difference -1.56, 95% CI -4.50 to 1.38; moderate-certainty evidence) with higher scores reflecting better quality of life. We downgraded the certainty of evidence for study limitations.

AUTHORS' CONCLUSIONS

Early AST probably extends time to death of any cause and time to death from prostate cancer. It may slightly decrease the rate of skeletal events. Rates of serious adverse events and quality of life may be similar. It may increase fatigue and may increase the risk of heart failure. Better quality trials would be particularly important to better understand the outcomes related to possible treatment-related harm, for which we only found low-certainty evidence.

The effect of androgen deprivation therapy on body composition in men with prostate cancer: systematic review and meta-analysis

INTRODUCTION

The use of androgen deprivation therapy (ADT) in the treatment of prostate cancer is associated with changes in body composition including increased fat and decreased lean mass. Limited information exists regarding the rate and extent of these changes. This systematic review was conducted to determine the effects of ADT on body composition in prostate cancer patients.

METHODS

Literature searches were conducted on MEDLINE, EMBASE and Web of Science for studies until January 2009. Only longitudinal studies that examined ADT and body composition in prostate cancer patients were included. Data were extracted on body weight, BMI, percentage of fat mass and lean body mass.

RESULTS

Sixteen studies (14 cohorts and 2 RCTs) met the inclusion criteria. Pooled data, calculated according to a random effects model, showed that ADT increased % body fat by on average 7.7% (95% CI 4.3, 11.2, from seven studies, P < 0.0001) and decreased % lean body mass by on average -2.8% (95% CI -3.6, -2.0, from six studies, P < 0.0001) but for both there was marked heterogeneity between studies (I2 = 99% I2 = 73%, respectively). Similarly, body weight (2.1%, P < 0.0001 from nine studies) and BMI (2.2%, P < 0.0001, from eight studies) increased significantly. More extensive changes were seen with longer duration of treatment.

CONCLUSIONS

Substantial increases in fat and declines in lean mass were observed in prostate cancer patients treated with ADT. Lifestyle changes or suitable interventions to minimize the effect of ADT on body composition need to be investigated.

IMPLICATIONS FOR CANCER SURVIVORS

Prostate cancer survivors should be made aware of the side effect of treatment on body composition and further work is required to determine what interventions can minimize the impact of ADT on body composition and therefore what evidence based advice they should be provided with. In general, though recommendation of a healthy diet and moderate exercise is reasonable.

Early Versus Delayed Androgen Deprivation for Prostate Cancer: New Fuel for an Old Debate

The purpose of this review is to discuss the recent increase in data supporting the use of androgen ablation early in the clinical course for patients with nonmetastatic prostate cancer. We systematically reviewed recent publications that report on the use of androgen deprivation (AD) in nonmetastatic prostate cancer patients from the 2003 and 2004 procedings of the American Society of Clinical Oncology, the 2003 and 2004 procedings of the American Urological Association as well as published literature from 2003 to 2005. Five recently published mature randomized trials of AD plus local therapy were evaluated plus two large data sets on the use of AD for patients with serologic relapse after local therapy. Four mature randomized studies demonstrate an overall survival benefit to the use of AD in conjunction with definitive local therapy (three with radiation and one with surgery). One retrospective analysis suggests that AD administered early after serologic progression improves overall survival, and one retrospective analysis shows a reduction in metastasis-free survival but has not yet shown an overall survival benefit. For patients with nonmetastatic prostate cancer with high-risk features, as well as those for serologic relapse, the use of AD before the development of metastatic disease is supported by long-term outcomes from a series of clinical trials. Consideration of AD is therefore warranted early in the clinical course of high-risk patients.

Combination hormonal therapy: a reassessment within advanced prostate cancer

Combination hormonal therapy, comprising a luteinising hormone-releasing hormone analogue (LHRHa) with an antiandrogen, is widely used in the treatment of advanced prostate cancer. There is ongoing debate regarding the use of combination hormonal therapy as opposed to LHRHa monotherapy. The pivotal consideration is whether there are adequate benefits with combination hormonal therapy in terms of increased survival and decreased disease progression to outweigh the increased risk of adverse events and additional cost. The most recent meta-analysis by the Prostate Cancer Trialists' Collaborative Group indicates a small but statistically significant survival benefit with combination hormonal therapy using nonsteroidal antiandrogens. It is, however, noteworthy that combined conclusions derived from such meta-analyses may not apply across each of the individual antiandrogens. Individual studies have reported differences between antiandrogens in terms of both tolerability and efficacy-for example, bicalutamide has been shown to be better tolerated than flutamide, and may be associated with improved survival. In addition, it is essential that treatment decisions are taken in consultation with the patient. Owing to an increasing proportion of cases presenting with early-stage disease, combination hormonal therapy is increasingly used in the neoadjuvant or adjuvant setting with radiotherapy and, in cases of prostate-specific antigen recurrence after prior localised therapy. Further data are awaited to optimise the use of combination hormonal therapy in these new settings.

Early versus late hormonal therapy for prostate cancer

Hormonal therapy remains the critical therapeutic option for men with advanced prostate cancer. However, considerable uncertainty remains regarding the appropriate choice/timing and actual benefits of hormonal therapy in various situations. This article reviews the relevant studies of immediate versus deferred hormonal therapy in patients with prostate cancer. The evidence from the data supports that early treatment is beneficial to many patients. Significant survival benefit of early hormonal therapy has been observed among patients with asymptomatic metastatic disease, node-positive but clinically localized disease after radical prostatectomy and lymphadenectomy, and advanced local/regional disease during and after radiotherapy.

Evolution of therapeutic approaches with luteinizing hormone–releasing hormone agonists in 2003

The role of hormone therapy in the current era of widespread testing for prostate-specific antigen (PSA) continues to evolve. Although still used in patients with metastatic disease, the most common uses of luteinizing hormone-releasing hormone (LHRH) agonist therapy are in the adjuvant and neoadjuvant settings with radiotherapy and sometimes with radical prostatectomy, as well as in the treatment of PSA-only recurrence. Immediate (adjuvant) hormone therapy after prostatectomy may provide a survival advantage relative to deferred treatment in high-risk patients, whereas the survival benefit of adjuvant therapy with radiation is clearer. Combined androgen blockade with an LHRH agonist and a nonsteroidal antiandrogen provides a very modest but statistically significant survival benefit relative to LHRH agonist monotherapy in patients with metastatic disease, but it has not been proved in those with less advanced disease. Intermittent hormone therapy appears to be effective in maintaining disease control for several years, but randomized studies are needed to determine if survival is at least equivalent to continuous therapy. Finally, LHRH agonist therapy is commonly used in the setting of biochemical or PSA-only recurrence. However, there are no randomized controlled trials to prove a survival benefit over observation. In summary, hormone therapy now plays a more important role at earlier stages of disease, consistent with the changing epidemiology of prostate cancer. Additional studies are needed, however, to define how to optimally use hormone therapy across various patient types.