Intermittent hormonal therapy in the treatment of metastatic prostate cancer: a randomized trial

Clinical efficacy of different androgen deprivation therapies for prostate cancer and evaluation based on dynamic-contrast enhanced magnetic resonance imaging

Objective

To evaluate the clinical efficacy of different androgen deprivation therapies for prostate cancer (PCa) based on dynamic-contrast enhanced magnetic resonance imaging (DCE-MRI).

Methods

104 patients with PCa were studied, all of whom were treated with androgen deprivation therapy. The patients were divided into a continuous group (continuous androgen deprivation therapy) and an intermittent group (intermittent androgen deprivation therapy) by random number table method, 52 cases/group. The therapeutic effect and DCE-MRI indices were compared and the relationship between DCE-MRI indices and clinical efficacy and the evaluation value of therapeutic efficacy were analyzed.

Results

The objective response rate (ORR) of the intermittent group was higher than that of the continuous group (p < 0.05), and there was no significant difference in disease control rate (DCR) between the two groups (p > 0.05). After treatment, volume transfer coefficient (Ktrans), reverse transfer constant (Kep), volume fraction (Ve), blood volume (BV), and blood flow (BF) in both groups were lowered, and those in the intermittent group were lower than the continuous group (p < 0.05). Ktrans, Kep, Ve, BF, and BV in the ORR group were lower than those in the non-ORR group (p < 0.05). Ktrans, Kep, Ve, BF, and BV were correlated with the therapeutic effect of PCa (p < 0.05). The AUC value of the combined detection of DCE-MRI indices in evaluating the therapeutic effect of PCa was greater than that of each index alone (p < 0.05).

Conclusion

Compared with continuous androgen deprivation therapy, intermittent androgen deprivation therapy has better clinical efficacy in the treatment of PCa, and DCE-MRI indices are related to the treatment efficacy of PCa and have an evaluation value.

Optimization Therapy by Coupling Intermittent Androgen Suppression with Impulsive Chemotherapy for a Prostate Cancer Model

Intermittent androgen suppression in the prostate cancer is often relapsed by the increasing of prostate specific antigen level during the on-treatment. Historically, chemotherapy has had a limited role in the treatment of prostate cancer. However, new agents are showing promise in patients with advanced disease. Intermittent androgen suppression plus chemotherapy in pulsed pattern has become an indispensable clinical scheme for prostate cancer, which is presented to describe the transformation mechanism for three kinds of cancer cells in this paper. The model is then extended to include the residual effect of chemotherapy which suppresses the cancer cells production, thereby preventing the relapse. The optimal controls represent the efficiencies of both intermittent androgen suppression and chemotherapy in suppressing relapse of prostate cancer. Based on an optimal algorithm, numerical simulations are implemented not only to show the optimal durations of on- and off-treatment and chemotherapy dosages but also to present the effectiveness of different strategies in inhibiting the relapse for three types of patients. Results reveal that the optimal intermittent androgen suppression scheme with alterable treatment cycles is pivotal for type I and II patients, in part because it can greatly reduce the on-treatment time and degrade the level of prostate specific antigen. Furthermore, optimal hybrid schedule even averts the relapse of prostate cancer for type II and III patients. Finally, comparing the prostate specific antigen under intermittent androgen suppression schedule with residual effect of chemotherapy to one without residual effect of chemotherapy demonstrates the validity of both our model and algorithms in lessening the prostate specific antigen and decreasing the chemotherapy dosages.

A Novel Nomogram to Identify Candidates for Focal Therapy Among Patients with Localized Prostate Cancer Diagnosed via Magnetic Resonance Imaging-Targeted and Systematic Biopsies: A European Multicenter Study

BACKGROUND

Suitable selection criteria for focal therapy (FT) are crucial to achieve success in localized prostate cancer (PCa).

OBJECTIVE

To develop a multivariable model that better delineates eligibility for FT and reduces undertreatment by predicting unfavorable disease at radical prostatectomy (RP).

DESIGN, SETTING, AND PARTICIPANTS

Data were retrospectively collected from a prospective European multicenter cohort of 767 patients who underwent magnetic resonance imaging (MRI)-targeted and systematic biopsies followed by RP in eight referral centers between 2016 and 2021. The Imperial College of London eligibility criteria for FT were applied: (1) unifocal MRI lesion with Prostate Imaging-Reporting and Data System score of 3-5; (2) prostate-specific antigen (PSA) ≤20 ng/ml; (3) cT2-3a stage on MRI; and (4) International Society of Urological Pathology grade group (GG) 1 and ≥6 mm or GG 2-3. A total of 334 patients were included in the final analysis.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was unfavorable disease at RP, defined as GG ≥4, and/or lymph node invasion, and/or seminal vesicle invasion, and/or contralateral clinically significant PCa. Logistic regression was used to assess predictors of unfavorable disease. The performance of the models including clinical, MRI, and biopsy information was evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analysis. A coefficient-based nomogram was developed and internally validated.

RESULTS AND LIMITATIONS

Overall, 43 patients (13%) had unfavorable disease on RP pathology. The model including PSA, clinical stage on digital rectal examination, and maximum lesion diameter on MRI had an AUC of 73% on internal validation and formed the basis of the nomogram. Addition of other MRI or biopsy information did not significantly improve the model performance. Using a cutoff of 25%, the proportion of patients eligible for FT was 89% at the cost of missing 30 patients (10%) with unfavorable disease. External validation is required before the nomogram can be used in clinical practice.

CONCLUSIONS

We report the first nomogram that improves selection criteria for FT and limits the risk of undertreatment.

PATIENT SUMMARY

We conducted a study to develop a better way of selecting patients for focal therapy for localized prostate cancer. A novel predictive tool was developed using the prostate-specific antigen (PSA) level measured before biopsy, tumor stage assessed via digital rectal examination, and lesion size on magnetic resonance imaging (MRI) scans. This tool improves the prediction of unfavorable disease and may reduce the risk of undertreatment of localized prostate cancer when using focal therapy.

A Phase 1b Adaptive Androgen Deprivation Therapy Trial in Metastatic Castration Sensitive Prostate Cancer

Background: We hypothesize that cancer survival can be improved through adapting treatment strategies to cancer evolutionary dynamics and conducted a phase 1b study in metastatic castration sensitive prostate cancer (mCSPC). Methods: Men with asymptomatic mCSPC were enrolled and proceeded with a treatment break after achieving > 75% PSA decline with LHRH analog plus an NHA. ADT was restarted at the time of PSA or radiographic progression and held again after achieving >50% PSA decline. This on-off cycling of ADT continued until on treatment imaging progression. Results: At data cut off in August 2022, only 2 of the 16 evaluable patients were off study due to imaging progression at 28 months from first dose of LHRH analog for mCSPC. Two additional patients showed PSA progression at 12.4 and 20.5 months and remain on trial. Since none of the 16 patients developed imaging progression at 12 months, the study succeeded in its primary objective of feasibility. The secondary endpoints of median time to PSA progression and median time to radiographic progression have not been reached at a median follow up of 26 months. Conclusions: It is feasible to use an individual’s PSA response and testosterone levels to guide intermittent ADT in mCSPC.

Randomised double-blind phase 3 clinical study testing impact of atorvastatin on prostate cancer progression after initiation of androgen deprivation therapy: study protocol

INTRODUCTION

Blood cholesterol is likely a risk factor for prostate cancer prognosis and use of statins is associated with lowered risk of prostate cancer recurrence and progression. Furthermore, use of statins has been associated with prolonged time before development of castration resistance (CR) during androgen deprivation therapy (ADT) for prostate cancer. However, the efficacy of statins on delaying castration-resistance has not been tested in a randomised placebo-controlled setting.This study aims to test statins' efficacy compared to placebo in delaying development of CR during ADT treatment for primary metastatic or recurrent prostate cancer. Secondary aim is to explore effect of statin intervention on prostate cancer mortality and lipid metabolism during ADT.

METHODS AND ANALYSIS

In this randomised placebo-controlled trial, a total of 400 men with de novo metastatic prostate cancer or recurrent disease after primary treatment and starting ADT will be recruited and randomised 1:1 to use daily 80 mg of atorvastatin or placebo. All researchers, study nurses and patients will be blinded throughout the trial. Patients are followed until disease recurrence or death. Primary outcome is time to formation of CR after initiation of ADT. Serum lipid levels (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and trigyserides) are analysed to test whether changes in serum cholesterol parameters during ADT predict length of treatment response. Furthermore, the trial will compare quality of life, cardiovascular morbidity, changes in blood glucose and circulating cell-free DNA, and urine lipidome during trial.

ETHICS AND DISSEMINATION

This study is approved by the Regional ethics committees of the Pirkanmaa Hospital District, Science centre, Tampere, Finland (R18065M) and Tarto University Hospital, Tarto, Estonia (319/T-6). All participants read and sign informed consent form before study entry. After publication of results for the primary endpoints, anonymised summary metadata and statistical code will be made openly available. The data will not include any information that could make it possible to identify a given participant.

TRIAL REGISTRATION NUMBER

Clinicaltrial.gov: NCT04026230, Eudra-CT: 2016-004774-17, protocol code: ESTO2, protocol date 10 September 2020 and version 6.

Initial Management of Noncastrate Advanced, Recurrent, or Metastatic Prostate Cancer: ASCO Guideline Update

PURPOSE

Update all preceding ASCO guidelines on initial hormonal management of noncastrate advanced, recurrent, or metastatic prostate cancer.

METHODS

The Expert Panel based recommendations on a systematic literature review. Recommendations were approved by the Expert Panel and the ASCO Clinical Practice Guidelines Committee.

RESULTS

Four clinical practice guidelines, one clinical practice guidelines endorsement, 19 systematic reviews with or without meta-analyses, 47 phase III randomized controlled trials, nine cohort studies, and two review papers informed the guideline update.

RECOMMENDATIONS

Docetaxel, abiraterone, enzalutamide, or apalutamide, each when administered with androgen deprivation therapy (ADT), represent four separate standards of care for noncastrate metastatic prostate cancer. Currently, the use of any of these agents in any particular combination or series cannot be recommended. ADT plus docetaxel, abiraterone, enzalutamide, or apalutamide should be offered to men with metastatic noncastrate prostate cancer, including those who received prior therapies, but have not yet progressed. The combination of ADT plus abiraterone and prednisolone should be considered for men with noncastrate locally advanced nonmetastatic prostate cancer who have undergone radiotherapy, rather than castration monotherapy. Immediate ADT may be offered to men who initially present with noncastrate locally advanced nonmetastatic disease who have not undergone previous local treatment and are unwilling or unable to undergo radiotherapy. Intermittent ADT may be offered to men with high-risk biochemically recurrent nonmetastatic prostate cancer. Active surveillance may be offered to men with low-risk biochemically recurrent nonmetastatic prostate cancer. The panel does not support use of either micronized abiraterone acetate or the 250 mg dose of abiraterone with a low-fat breakfast in the noncastrate setting at this time.Additional information is available at www.asco.org/genitourinary-cancer-guidelines.

An analysis of survival in patients with castrate-resistant prostate cancer receiving enzalutamide with treatment breaks

Objective:

Enzalutamide is effective in treating metastatic castrate-resistant prostate cancer (mCRPC) but can have side effects that require treatment breaks (TB). We conducted a retrospective analysis of outcomes of patients who had extended TB due to toxicity compared to continuous dosing.

Methods:

Patients prescribed enzalutamide for mCRPC from September 2011 to February 2018 were included. TB was defined as an interruption of four weeks or more. Overall survival (OS) from enzalutamide start, time to prostate-specific antigen failure (TTF) and total enzalutamide treatment time (TTT) were analysed for TB and continuous responders (>50% PSA drop), and a significance level of 0.05 was assigned.

Results:

A total of 110 patients were continuous responders, and 29 had TB. The median number of interruptions was one (range 1–7), and time on treatment was 70% in the TB group. The TB group had significantly improved OS (100 vs. 60 months; hazard ratio=1.8, 95% confidence interval 1.17–2.77, p=0.02), prolonged TTF (median 11 vs. 6 months; p=0.008) and TTT (median 15 vs. 8 months; p=0.0001).

Conclusion:

Extended TB do not seem to impact OS or treatment duration adversely in patients who are responding and experiencing toxicity, and may be a useful option in managing toxicity. Prospective trials could explore this further.

Level of evidence:

Level 2c.

Population-based Assessment of Intermittent Androgen Deprivation Therapy Utilization for Relapsed, Nonmetastatic, Hormone-sensitive Adenocarcinoma of the Prostate

OBJECTIVES

Androgen deprivation therapy (ADT) is the standard of care for men with nonmetastatic hormone-sensitive prostate cancer (nmHSPC) after treatment failure. Although intermittent ADT (iADT) is noninferior to continuous ADT for prostate cancer outcomes, with superior quality of life and cost-to-benefit ratio, little is known regarding its real-world utilization. The authors aimed to determine the utilization of iADT in a Canadian Provincial Cancer Program for relapsed nmHSPC and identified risk factors associated with the nonreceipt of iADT.

MATERIALS AND METHODS

This retrospective population-based cohort study used linked administrative databases to identify all patients with relapsed nmHSPC from 2012 to 2016 and quantified ADT prescription history. Patients were defined as iADT eligible if prostate-specific antigen (PSA) was <4 ng/mL and trending downwards on ≥2 sequential PSAs after ≥6 months of ADT. Univariable and multivariable logistic regression analyses were performed to determine factors associated with nonreceipt of iADT.

RESULTS

A total of 601 men with relapsed, nmHSPC were included with a median age at relapse of 73 (range, 46 to 96), pre-ADT PSA of 12.2 ng/mL, and a median pre-ADT PSA doubling time of 7.8 months. 80.9% of the cohort were eligible to receive iADT and 74.4% were treated with iADT. On multivariable analysis, patients originally treated with surgery (odds ratio [OR], 0.19; 95% confidence interval [CI], 0.08-0.46) or having a Gleason Score ≥8 (OR, 0.30; 95% CI, 0.12-0.78) had decreased odds of receipt of iADT. Patients with longer PSA doubling times were more likely to receive iADT (OR, 2.71; 95% CI, 1.17-6.31).

CONCLUSIONS

The utilization of iADT was relatively common for men in Manitoba during the study period, however, the uptake of iADT can be improved among identified subgroups.

Resistance to Antiandrogens in Prostate Cancer: Is It Inevitable, Intrinsic or Induced?

Increasingly sophisticated therapies for chemical castration dominate first-line treatments for locally advanced prostate cancer. However, androgen deprivation therapy (ADT) offers little prospect of a cure, as resistant tumors emerge rather rapidly, normally within 30 months. Cells have multiple mechanisms of resistance to even the most sophisticated drug regimes, and both tumor cell heterogeneity in prostate cancer and the multiple salvage pathways result in castration-resistant disease related genetically to the original hormone-naive cancer. The timing and mechanisms of cell death after ADT for prostate cancer are not well understood, and off-target effects after long-term ADT due to functional extra-prostatic expression of the androgen receptor protein are now increasingly being recorded. Our knowledge of how these widely used treatments fail at a biological level in patients is deficient. In this review, I will discuss whether there are pre-existing drug-resistant cells in a tumor mass, or whether resistance is induced/selected by the ADT. Equally, what is the cell of origin of this resistance, and does it differ from the treatment-naïve tumor cells by differentiation or dedifferentiation? Conflicting evidence also emerges from studies in the range of biological systems and species employed to answer this key question. It is only by improving our understanding of this aspect of treatment and not simply devising another new means of androgen inhibition that we can improve patient outcomes.

Intermittent versus continuous androgen deprivation therapy for advanced prostate cancer

Androgen deprivation therapy (ADT) is still a mainstay of treatment for advanced prostate cancer. Continuous ADT causes considerable patient morbidity including sexual dysfunction, poor mood and physical capacity, changes in body composition and health-care-related costs. Intermittent ADT has been used as an approach to ADT monotherapy to limit morbidity by enabling cyclical recovery of serum testosterone levels. To date, a number of well-performed randomized controlled trials and meta-analyses have demonstrated statistically insignificant differences in oncological outcomes between intermittent and continuous ADT monotherapy. Sexual outcomes, morbidity profiles and cost-savings favour intermittent therapy in most randomized trials, but the benefit for clinical practice is unclear. Despite the growing body of evidence, the optimal administration regime for ADT has not been clearly established and incorporation of adjunctive upfront treatments such as chemotherapy and novel anti-androgen agents has further hampered progress. Recommendations by authoritative urological and oncological societies regarding the use of intermittent ADT are limited. The potential benefits of reduced morbidity for a particular patient must be considered in light of the possible oncological outcomes. Although the oncological changes associated with intermittent ADT are controversial, intermittent ADT does seem to provide symptomatic benefit in patients compared with continuous ADT. However, careful selection of suitable patients is crucial.

Quality-of-Life Assessment and Reporting in Prostate Cancer: Systematic Review of Phase 3 Trials Testing Anticancer Drugs Published Between 2012 and 2018

Quality of life (QoL) is not included among the end points in many studies, and QoL results are underreported in many phase 3 oncology trials. We performed a systematic review to describe QoL prevalence and heterogeneity in QoL reporting in recently published prostate cancer phase 3 trials. A PubMed search was performed to identify primary publications of randomized phase 3 trials testing anticancer drugs in prostate cancer, issued between 2012 and 2018. We analyzed QoL inclusion among end points, presence of QoL results, and methodology of QoL analysis. Seventy-two publications were identified (15 early-stage, 20 advanced hormone-sensitive, and 37 castration-resistant prostate cancer [CRPC]). QoL was not listed among study end points in 23 studies (31.9%) (40.0% early stage, 40.0% advanced hormone sensitive, and 24.3% CRPC). QoL results were absent in 15 (30.6%) of 49 primary publications of trials that included QoL among end points. Overall, as a result of absent end point or unpublished results, QoL data were lacking in 38 (52.8%) primary publications (53.3% early stage, 55.0% in advanced hormone sensitive, and 51.4% in CRPC). The most commonly used QoL tools were Functional Assessment of Cancer Therapy-Prostate (FACT-P) (21, 53.8%) and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) (14, 35.9%); most common methods of analysis were mean changes or mean scores (28, 71.8%), time to deterioration (14, 35.9%), and proportion of patients with response (10, 25.6%). In conclusion, QoL data are lacking in a not negligible proportion of recently published phase 3 trials in prostate cancer, although the presence of QoL results is better in positive trials, especially in CRPC. The methodology of QoL analysis is heterogeneous for type of instruments, analysis, and presentation of results.

Translating insights into tumor evolution to clinical practice: promises and challenges

Accelerating technological advances have allowed the widespread genomic profiling of tumors. As yet, however, the vast catalogues of mutations that have been identified have made only a modest impact on clinical medicine. Massively parallel sequencing has informed our understanding of the genetic evolution and heterogeneity of cancers, allowing us to place these mutational catalogues into a meaningful context. Here, we review the methods used to measure tumor evolution and heterogeneity, and the potential and challenges for translating the insights gained to achieve clinical impact for cancer therapy, monitoring, early detection, risk stratification, and prevention. We discuss how tumor evolution can guide cancer therapy by targeting clonal and subclonal mutations both individually and in combination. Circulating tumor DNA and circulating tumor cells can be leveraged for monitoring the efficacy of therapy and for tracking the emergence of resistant subclones. The evolutionary history of tumors can be deduced for late-stage cancers, either directly by sampling precursor lesions or by leveraging computational approaches to infer the timing of driver events. This approach can identify recurrent early driver mutations that represent promising avenues for future early detection strategies. Emerging evidence suggests that mutational processes and complex clonal dynamics are active even in normal development and aging. This will make discriminating developing malignant neoplasms from normal aging cell lineages a challenge. Furthermore, insight into signatures of mutational processes that are active early in tumor evolution may allow the development of cancer-prevention approaches. Research and clinical studies that incorporate an appreciation of the complex evolutionary patterns in tumors will not only produce more meaningful genomic data, but also better exploit the vulnerabilities of cancer, resulting in improved treatment outcomes.

Revisiting Intermittent Therapy in Metastatic Prostate Cancer: Can Less Be More in the "New World Order"?

CONTEXT

Androgen deprivation therapy (ADT) is the standard of care for men with metastatic hormone-sensitive prostate cancer (HSPC) and a potential treatment option in those with prostate-specific antigen relapse after local therapy. Based on promising biological and preclinical data, several clinical trials compared the efficacy of intermittent androgen deprivation (IAD) versus continuous androgen deprivation (CAD) with the objective of delaying disease progression and improving survival and quality of life (QoL).

OBJECTIVE

The objective of this review is to revisit the concept of IAD in the "new world order" and reconsider whether it has a potential clinical role in an era where we have seen unprecedented progress in the management of patients with metastatic HSPC.

EVIDENCE ACQUISITION

MEDLINE, Embase, and the Cochrane Library databases were searched for randomized controlled trials comparing IAD and CAD therapies. References of retrieved articles were also searched. Articles with at least 100 randomized patients, which were published in 2008 or later and had data on overall survival or QoL outcomes, were included.

EVIDENCE SYNTHESIS

The evidence to date cannot exclude inferiority of IAD compared with CAD with respect to survival outcomes. The hazard ratios in metastatic disease indicate less favorable survival with IAD. No superiority trial conclusively favored IAD or CAD. Two trials demonstrated noninferiority of IAD, although the noninferiority margins (NIMs) are clinically concerning. Another trial could not exclude noninferiority. A modest but temporary QoL and symptom benefit generally favoring IAD was observed.

CONCLUSIONS

IAD has not conclusively demonstrated an impact on disease progression or survival, and has only modest effects on QoL and symptoms measured in the short term. As such, it is not the standard of care, particularly in the era where we have seen unprecedented survival impact with combination ADT+docetaxel or abiraterone +prednisone. IAD may need to be reassessed in the context of current therapies, ideally driven by biological rationale, with the goal of minimizing physical and financial toxicities with appropriately designed informative clinical trials.

PATIENT SUMMARY

In this report, we looked at two hormone therapy approaches for prostate cancer that is still sensitive to castration: one with treatment breaks and one without. Patients may tolerate therapy with breaks more easily, but this effect is not sustained and is not associated with better longevity. The best longevity is seen in patients who receive newer hormone therapies or chemotherapy in addition to continuous hormone therapy. Whether these newer therapies would be as effective if given intermittently is an important but unanswered question.

Effect of adjuvant hormone therapy in patients with prostate cancer: A meta-analysis of randomized controlled trials

OBJECTIVES

To summarize the evidence regarding the treatment effect of adjuvant hormone therapy (AHT) in patients with prostate cancer (PCa). AHT following radiotherapy, chemotherapy, or surgery is widely used in patients with PCa. However, the treatment effect is inconsistent in individual trials.

METHODS

The electronic databases including PubMed, EmBase, and Cochrane Library were searched to identify randomized controlled trials (RCTs) in September 2016. RCTs that evaluated the effects of AHT in patients with PCa were included. Hazard ratio (HR) and relative risks (RR) were used to measure the treatment effects of AHT using a random effects model. The analyses were further stratified by factors that could affect the treatment efficacy.

RESULTS

A total of 14,594 potential studies were identified, and 27 RCTs were included. Compared with the control group, patients who received AHT were associated with a significant improvement in overall survival (OS) (HR: 0.78; 95% confidence interval [CI]: 0.71-0.85; P <.001), disease-free survival (DFS) (HR: 0.50; 95% CI: 0.39-0.65; P <.001), total mortality (RR: 0.90; 95% CI: 0.85-0.96; P = .001), recurrence (RR: 0.70; 95% CI: 0.60-0.81; P <.001), and disease-specific mortality (RR: 0.70; 95% CI: 0.56-0.87; P <.001). However, no significant difference was observed between AHT and control for response rate (RR: 1.75; 95% CI: 0.91-3.37; P = .095).

CONCLUSIONS

The findings of this meta-analysis confirmed that patients who received AHT had a significant improvement in OS, DFS, total mortality, recurrence, and disease-specific mortality. Further, large-scale RCTs are required to evaluate the treatment effect in specific subpopulations.

RETRACTED: Recommandations françaises du Comité de Cancérologie de l’AFU – Actualisation 2018–2020 : cancer de la prostate French ccAFU guidelines – Update 2018–2020: Prostate cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Cet article est retiré de la publication à la demande des auteurs car ils ont apporté des modifications significatives sur des points scientifiques après la publication de la première version des recommandations. Le nouvel article est disponible à cette adresse: DOI:10.1016/j.purol.2019.01.007. C’est cette nouvelle version qui doit être utilisée pour citer l’article. This article has been retracted at the request of the authors, as it is not based on the definitive version of the text because some scientific data has been corrected since the first issue was published. The replacement has been published at the DOI:10.1016/j.purol.2019.01.007. That newer version of the text should be used when citing the article.

Risks of Major Long-Term Side Effects Associated with Androgen-Deprivation Therapy in Men with Prostate Cancer

STUDY OBJECTIVE

To examine the risks and compare the occurrences of major long-term side effects (sexual dysfunction, bone fractures, diabetes, cardiovascular morbidity, acute myocardial infarction [MI], and dementia) in patients with prostate cancer who received androgen-deprivation therapy (ADT) with those who did not.

DESIGN

Propensity score-matched retrospective cohort study using Medicare claims data.

DATA SOURCE

National Cancer Institute's Surveillance, Epidemiology, and End Results Program-Medicare linked database.

PATIENTS

A total of 201,797 patients 66 years or older who were diagnosed with any stage of prostate cancer between 1992 and 2009; of these, 94,528 patients received ADT; 107,269 patients did not.

MEASUREMENTS AND MAIN RESULTS

We identified receipt of ADT and number of claims for ADT, and ascertained the long-term treatment-related side effects that occurred during 19 years of follow-up, from 1992-2010, from Medicare claims data. Cox proportional hazards models were used to estimate the incidences and hazard ratios (HRs) of newly developed side effects. Among all potential long-term side effects, the risk of bone fractures was highest (HR 1.39, 95% confidence interval [CI] 1.35-1.43), followed by diabetes (HR 1.21, 95% CI 1.18-1.24), dementia (HR 1.16, 95% CI 1.13-1.20), coronary heart disease (HR 1.12, 95% CI 1.09-1.14), and acute MI (HR 1.11, 95% CI 1.08-1.15) in those who received ADT compared with those who did not. The HRs for bone fractures and diabetes increased steadily as the number of ADT doses increased, indicating a linear trend in the dose-response relationship. Compared with patients who received active surveillance, ADT was associated with a 12% increased risk of sexual dysfunction (HR 1.12, 95% CI 1.05-1.20). The HR for sexual dysfunction increased to 1.68 (95% CI 1.59-1.77) when ADT was combined with radiation therapy and to 3.54 (95% CI 3.26-3.85) when ADT was combined with radiation and surgery.

CONCLUSION

The results of this study demonstrated that in men with prostate cancer, receipt of ADT was associated with higher risks of bone fractures, diabetes, dementia, coronary heart disease, acute MI, and sexual dysfunction than in those who did not receive ADT.

Racial, Socioeconomic, and Geographic Disparities in the Receipt, Timing to Initiation, and Duration of Adjuvant Androgen Deprivation Therapy in Men with Prostate Cancer

OBJECTIVE

This retrospective cohort study aims to examine the receipt, timing to initiation, and duration of androgen deprivation therapy (ADT) in men with prostate cancer by race/ethnicity, socioeconomic status, and geographic location.

METHODS

The study population are patients from Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database, who were 66 years or older and newly diagnosed with stage III and IV prostate cancer in 1992-2009 and underwent radiation therapy, where ADT was proven to be highly beneficial and its use was considered as most appropriate (n = 12,170). We use logistic regression to examine the receipt of ADT and linear regression to study factors associated with time to ADT initiation while controlling for baseline characteristics.

RESULTS

Overall, 77% of eligible patients received at least one form of ADT in combination with radiation therapy, of which 12% underwent orchiectomy and the rest received ADT, and 77.2% of non-Hispanic white and 80.7% of Hispanic patients received ADT compared to 73.8% of non-Hispanic black. After adjustment for demographic and tumor characteristics, black men and men of other races are less likely to receive ADT compared to white counterparts (OR = 0.64 and 0.74, respectively). The median time from cancer diagnosis to ADT initiation is 2 months. Once initiated, men received a median of seven drug injections. After controlling for covariates, race/ethnicity and geographic location (SEER areas) are associated with early initiation of therapy. White, Hispanic men and men living in the South initiate ADT earlier.

CONCLUSION

Significant racial disparities exist in the receipt and use of this highly beneficial therapy, and there are geographic variations in the utilization of this therapy.

Long-term treatment outcomes of intermittent androgen deprivation therapy for relapsed prostate cancer after radical prostatectomy

PURPOSE

Intermittent androgen deprivation therapy is an effective treatment for metastatic prostate cancer. However, no study to date has evaluated the long-term outcomes of this treatment among patients with prostate cancer after radical prostatectomy. We retrospectively examined the treatment outcomes of patients with prostate-specific antigen recurrence who underwent radical prostatectomy at our department.

MATERIALS AND METHODS

Of the 690 patients who underwent radical prostatectomy for local prostate cancer between 1988 and 2011, 129 patients who received androgen deprivation therapy for prostate-specific antigen recurrence were included in this study. Patient characteristics, luteinizing hormone-releasing hormone agonist administration, and outcomes were compared between the intermittent androgen deprivation group (n = 66) and the continuous androgen deprivation therapy group (n = 63). The non-recurrence and overall survival rates were compared between groups.

RESULTS

Thirty-six patients (27.9%) experienced recurrence after luteinizing hormone-releasing hormone agonist administration. The 5-year non-recurrence rate and 10-year overall survival rate were higher in the intermittent group (92.9%) than in the continuous group (92.9 vs 57.9%, P < 0.001; and 95.9% vs 84.3%, P = 0.047, respectively). Furthermore, 63 patients (48.8%) showed a PSA nadir of less than 0.01 ng/mL after initiation of luteinizing hormone-releasing hormone agonist; among these patients, the non-recurrence rate was significantly higher in the intermittent androgen deprivation group (P = 0.003).

CONCLUSIONS

Intermittent androgen deprivation therapy for prostate specific antigen recurrence after radical prostatectomy contributed to improvement of the non-recurrence rate and overall survival, and can be considered an effective therapy for better prognosis.

Cognitive function in patients on androgen suppression: A prospective, multicentric study

OBJECTIVE

To assess the effect of androgen deprivation therapy (ADT) on cognitive performance (CP) in patients with prostate cancer (PCa) after 6 months of treatment with luteinizing hormone-releasing hormone (LHRH) analogues.

MATERIAL AND METHODS

Prospective, observational, multicentre, open-label study of patients diagnosed with nonmetastatic or asymptomatic metastatic PCa scheduled to receive LHRH analogues for≥6 months. We assessed four CP domains at baseline and after 6 months of ADT: 1) Working memory: Wechsler Adult Intelligence Scale III (WAIS III) Digit Span Subtest (WAIS III-Digit); 2) Visual memory: ad hoc visual memory test; 3) Visuospatial ability: Judgement of Line Orientation (JLO) and Mental Rotation of Three-Dimensional Objects (3D-Rotation); and 4) Nonverbal analytical reasoning: WAIS III Matrix Reasoning Test (WAIS III-MRT). Changes outside the baseline 95% confidence intervals were considered significant.

RESULTS

A total of 308 patients completed the study. Of these, 245 (79.6%) experienced no statistically significant changes on any test and 63 patients (20.4%) experienced significant changes in ≥1 test. Of these, most presented a change in only one test, distributed evenly between improvements (58 patients; 18.8%) and worsening (56 patients; 18.2%). For individual tests, most patients (87.8% to 91.8%) had no change from baseline; however, the significant changes (improvement vs. deterioration, respectively) were as follows: WAIS III-Digit (6.3% vs. 5.9%); visual memory (5.3% vs. 5.7%); JLO (5.3% vs. 4.5%); 3D-Rotation (4.1% vs. 4.1%); and WAIS III-MRT (4.8% vs. 5.8%).

CONCLUSIONS

CP in patients with PCa does not appear to be adversely affected by 6 months of LHRH analogue administration.

Intermittent androgen deprivation therapy in patients with prostate cancer: Connecting the dots

Intermittent androgen deprivation therapy (IADT) is now being increasingly opted by the treating physicians and patients with prostate cancer. The most common reason driving this is the availability of an off-treatment period to the patients that provides some relief from treatment-related side-effects, and reduced treatment costs. IADT may also delay the progression to castration-resistant prostate cancer. However, the use of IADT in the setting of prostate cancer has not been strongly substantiated by data from clinical trials. Multiple factors seem to contribute towards this inadequacy of supportive data for the use of IADT in patients with prostate cancer, e.g., population characteristics (both demographic and clinical), study design, treatment regimen, on- and off-treatment criteria, duration of active treatment, endpoints, and analysis. The present review article focuses on seven clinical trials that evaluated the efficacy of IADT vs. continuous androgen deprivation therapy for the treatment of prostate cancer. The results from these clinical trials have been discussed in light of the factors that may impact the treatment outcomes, especially the disease (tumor) burden. Based on evidence, potential candidate population for IADT has been suggested along with recommendations for the use of IADT in patients with prostate cancer.

Treatment of Metastatic Prostate Cancer in Older Adults

The aging of the population, along with rising life expectancy, means that increasing numbers of older men will be diagnosed with prostate cancer, and a large proportion of these men will present with metastatic disease. In this paper, we discuss recent advances in prostate cancer treatment. In particular, we review management approaches for older patients with metastatic prostate cancer based on the decision tree developed by the International Society of Geriatric Oncology, which categorized older men as "fit," "vulnerable," and "frail" according to comprehensive geriatric assessment.

[CCAFU french national guidelines 2016-2018 on prostate cancer]

OBJECTIVES

The purpose of the guidelines national committee CCAFU was to propose updated french guidelines for localized and metastatic prostate cancer (PCa).

METHODS

A Medline search was achieved between 2013 and 2016, as regards diagnosis, options of treatment and follow-up of PCa, to evaluate different references with levels of evidence.

RESULTS

Epidemiology, classification, staging systems, diagnostic evaluation are reported. Disease management options are detailed. Recommandations are reported according to the different clinical situations. Active surveillance is a major option in low risk PCa. Radical prostatectomy remains a standard of care of localized PCa. The three-dimensional conformal radiotherapy is the technical standard. A dose of > 74Gy is recommended. Moderate hypofractionation provides short-term biochemical control comparable to conventional fractionation. In case of intermediate risk PCa, radiotherapy can be combined with short-term androgen deprivation therapy (ADT). In case of high risk disease, long-term ADT remains the standard of care. ADT is the backbone therapy of metastatic disease. In men with metastases at first presentation, upfront chemotherapy combined with ADT should be considered as a new standard. In case of metastatic castration-resistant PCa (mCRPC), new hormonal treatments and chemotherapy provide a better control of tumor progression and increase survival.

CONCLUSIONS

These updated french guidelines will contribute to increase the level of urological care for the diagnosis and treatment for prostate cancer. © 2016 Elsevier Masson SAS. All rights reserved.

Saudi oncology society and Saudi urology association combined clinical management guidelines for prostate cancer

This is an update to the previously published Saudi guidelines for the evaluation, medical, and surgical management of patients diagnosed with prostate cancer. It is categorized according to the stage of the disease using the tumor node metastasis staging system 7(th) edition. The guidelines are presented with supporting evidence level, they are based on comprehensive literature review, several internationally recognized guidelines, and the collective expertise of the guidelines committee members (authors) who were selected by the Saudi oncology society and Saudi urological association. Considerations to the local availability of drugs, technology, and expertise have been regarded. These guidelines should serve as a roadmap for the urologists, oncologists, general physicians, support groups, and health care policy makers in the management of patients diagnosed with adenocarcinoma of the prostate to.

International survey of androgen deprivation therapy (ADT) for non-metastatic prostate cancer in 19 countries

Background

Continuous androgen deprivation therapy (CADT) is commonly used for patients with non-metastatic prostate cancer as primary therapy for high-risk disease, adjuvant therapy together with radiation or for recurrence after initial local therapy. Intermittent ADT (IADT), a recently developed alternative strategy for providing ADT, is thought to potentially reduce adverse effects, but little is known about practice patterns relating to it. We aimed to describe factors related to physicians’ ADT use and modality for patients with non-metastatic prostate cancer.

Methods

A 45 min online survey was completed by urologists and oncologists responsible for treatment decisions for non-metastatic prostate cancer from 19 countries with high or increasing prevalence of non-metastatic prostate cancer.

Results

There were 441 treating physicians who completed the survey which represented 99 177 patients with prostate cancer under their care, of which 76 386 (77%) had non-metastatic prostate cancer. Of patients with non-metastatic prostate cancer, 38% received ADT (37% gonadotropin-releasing hormone (GnRH), 2% orchiectomy); among patients on GnRH, 54% received CADT (≥6 without >3 months interruption), 23% IADT and 23% <6 months. Highest rates of ADT were reported among oncologists (62%) and in Eastern Europe (Czech Republic, Hungary and Poland). Prostate-specific antigen (PSA) levels (65%), Gleason score (52%) and treatment guidelines (48%) were the most common reasons for CADT whereas PSA levels (54%), patient request (48%), desire to maintain sexual function (40%), patient age and comorbidities (38%) were cited most frequently as reasons for IADT.

Conclusions

This international survey with 441 treating physicians from 19 countries showed that ADT is commonly used in treating patients with non-metastatic prostate cancer, and type of ADT is influenced by high-risk criteria (PSA and Gleason), treatment guidelines and patient preferences. IADT use was primarily driven by PSA levels, patient request and patient age/comorbidities, likely reflecting an attempt to minimise adverse effects of ADT in patients with lower risk tumours.

Prostate Cancer Patients' Preferences for Intermittent vs. Continuous Androgen Deprivation-A Pilot Institutional Study

INTRODUCTION

With locally advanced, recurrent, and metastatic prostate cancer patients, patient preference between intermittent (IAD) and continuous (CAD) androgen deprivation therapy has not been investigated. The goal of the study was to determine patients' preference for IAD vs. CAD therapy. The secondary aim was to elucidate demographic or treatment variables that may affect a patient's preference for one type of hormonal treatment.

MATERIALS AND METHODS

Using a tradeoff model that demonstrates the difference in outcome between IAD and CAD, a survey questionnaire was developed and administered to prostate cancer patients at the Odette Cancer Centre at Sunnybrook Health Sciences Centre in Toronto, Ontario, Canada. Only patients who had (1) locally advanced prostate cancer, (2) been previously treated for prostate cancer with relapsing prostate-specific antigen, or (3) slow metastatic disease were asked to participate. Data related to patients' demographic information and their decisional preference factors were collected.

RESULTS AND CONCLUSIONS

Overall, 36 of 53 (68%) patients completed the survey. Most patients favoured IAD (n = 32) over CAD (n = 4). Patients currently on radical treatment (adjuvant hormone therapy and radiation therapy) preferred CAD compared with patients who were not on radical treatment (P = .044). Patients with high (>20 ng/L) pretreatment prostate-specific antigen showed preference for CAD; however, this was not statistically significant (P = 0.07). Patients from both groups viewed quality of life as the strongest influence on their treatment preference, but had diverging opinions on side effects and general well being. The results of this pilot study could serve as a guide for future studies; a larger study combined with qualitative methodology may better address patients' needs and minimize any regret over their hormonal treatment.

Androgen Deprivation Therapy in Prostate Cancer - Current Status in M1 Patients

Androgen deprivation therapy is the cornerstone treatment for metastatic prostate cancer. It can be done either surgically or medically. Luteinizing hormone-releasing hormone agonists and antagonist are the most effective drugs, with different side effects and modes of action, but no clear efficacy differences. Adding a non-steroidal antiandrogen adds a marginal benefit but also significant side effects and costs. Non-steroidal antiandrogens should not be used as monotherapy. In most patients with metastases, immediate castration is the standard of care. The intermittent modality is apparently non-inferior to the continuous one, with some other benefits. Upfront chemotherapy added to castration should be considered as the new standard of care in many metastatic patients. Castration leads to many adverse effects, some potentially life-threatening such as cardiovascular side effects.

Evaluating Intermittent Androgen-Deprivation Therapy Phase III Clinical Trials: The Devil Is in the Details

PURPOSE

Intermittent androgen deprivation (IAD) has been widely tested in prostate cancer. However, phase III trials testing continuous androgen deprivation (CAD) versus IAD have reached inconclusive and seemingly contradictory results. Different design and conduct issues must be critically evaluated to better interpret the results.

PATIENTS AND METHODS

Seven published phase III trials were examined for prespecified design and outcomes. Treatment specifications; primary end point; superiority versus noninferiority design assumptions, including magnitude of assumed versus observed noninferiority margin (NIM); duration of follow-up; and quality-of-life (QOL) outcomes were considered in terms of the results and conclusions reported.

RESULTS

Five trials had a superiority and three had a noninferiority primary hypothesis. Only three trials had a uniform population and overall survival (OS) end point. All trials observed better outcomes in terms of OS and progression-free survival (PFS) than assumed at time of study design, translating into prespecified NIMs or hazard ratios that reflected larger absolute differences in OS or PFS between arms. Lower-than-expected event rates also reduced statistical power for the trials. Other factors, including length of follow-up, cause of death, QOL, and primary end point, and their impact on trial interpretation are discussed.

CONCLUSION

No trial to date has demonstrated survival superiority of IAD compared with CAD. Trials concluding IAD is noninferior to CAD were based on wide NIMs that included clinically important survival differences, not likely to be considered comparable by physicians or patients. Interim analyses relying on short follow-up and including a majority of non-prostate cancer deaths will favor a noninferiority conclusion and should be interpreted cautiously. Adequate follow-up is required to ensure capture of prostate cancer deaths in both superiority and noninferiority trials.

The effect of continuous androgen deprivation treatment on prostate cancer patients as compared with intermittent androgen deprivation treatment

Purpose

To investigate the efficacy of androgen deprivation treatment (ADT) between continuous and intermittent ADT.

Materials and Methods

Between January 2006 and May 2015, 603 patients were selected and divided into continuous ADT (CADT) (n=175) and intermittent ADT (IADT) (n=428) groups. The median follow-up in this study was 48.19 (1.0-114.0) months. The primary end point was time to castration resistant prostate cancer (CRPC). The types of ADT were monotherapy and maximal androgen blockade (i.e., luteinizing hormone-releasing hormone agonist and antiandrogen).

Results

The characteristics of patients showed no significant differences between the CADT and IADT groups, except for the Gleason score (p<0.001). The median time to CRPC of all enrolled patients with ADT was 20.60±1.60 months. The median time to CRPC was 11.20±1.31 months in the CADT group as compared with 22.60±2.08 months in the IADT group. In multivariate analysis, percentage of positive core (p=0.047; hazard ratio [HR], 0.976; 95% confidence interval [CI], 0.953-1.000), Gleason score (p=0.007; HR, 1.977; 95% CI, 1.206-3.240), lymph node metastasis (p=0.030; HR, 0.498; 95% CI, 0.265-0.936), bone metastasis (p=0.028; HR, 1.921; 95% CI, 1.072-3.445), and CADT vs. IADT (p=0.003; HR, 0.254; 95% CI. 0.102-0.633) were correlated with the duration of progression to CRPC. The IADT group presented a significantly longer median time to CRPC compared with the CADT group. Additionally, patients in the IADT group showed a longer duration in median time to CRPC in subgroup analysis according to the Gleason score.

Conclusions

This study found that IADT produces a longer duration in median time to CRPC than does CADT.

The role of intermittent androgen deprivation therapy in the management of biochemically recurrent or metastatic prostate cancer

Androgen deprivation therapy (ADT) is a well-established treatment for locally advanced, biochemically recurrent and metastatic prostate cancer. However, it is associated with significant side effects including hot flashes, loss of libido and erectile function, muscular atrophy, metabolic abnormalities, and osteoporosis. In attempt to mitigate the side effects of ADT while retaining the oncological benefits, an approach of intermittent ADT (IAD) has been investigated. IAD involves alternating periods of treatment with intervals off treatment to allow hormone recovery. PSA thresholds are triggers for withdrawing and reinitiating therapy. Potential advantages of IAD include improved quality of life with fewer side effects and reduced cost. Delays in the development of hormone resistance have not been demonstrated clinically. The appropriate use of IAD requires patient selection and close monitoring of quality of life and disease status. This review presents the most recent evidence on the role of IAD in the management of prostate cancer.

Systemic therapy for the treatment of hormone-sensitive metastatic prostate cancer: from intermittent androgen deprivation therapy to chemotherapy

Treatment of advanced prostate cancer has changed considerably in recent years, but the vast majority of advances have been made in patients with metastatic castration-resistant disease. There have been relatively fewer advances in the earlier, hormonally responsive stage of metastatic disease. Since the empiric establishment of androgen deprivation therapy as first-line therapy for metastatic prostate cancer decades ago, there have been multiple studies looking at variations of suppressing testosterone, but the overall paradigm has not been strongly challenged until more recently. In particular, the dramatic results reported by the CHAARTED trial not only bring chemotherapy to an arena historically dominated solely by hormonal therapy but also stimulate renewed efforts into improving upon our management of metastatic hormone-sensitive prostate cancer.

A review of continuous vs intermittent androgen deprivation therapy: redefining the gold standard in the treatment of advanced prostate cancer. Myths, facts and new data on a ″perpetual dispute″

OBJECTIVES

To review the literature and present new data of continuous androgen deprivation therapy (ADT) vs intermittent androgen deprivation (IAD) as therapies for prostate cancer in terms of survival and quality of life and clarify practical issues in the use of IAD.

MATERIALS AND METHODS

We conducted a systematic search on Medline and Embase databases using ″prostatic neoplasm″ and ″intermittent androgen deprivation″ as search terms. We reviewed meta-analyses, randomised controlled trials, reviews, clinical trials and practise guidelines written in English from 2000 and onwards until 01/04/2013. Ten randomized controlled trials were identified. Seven of them published extensive data and results randomizing 4675 patients to IAD versus CAD. Data from the other three randomized trials were limited.

RESULTS

Over the last years studies confirmed that IAD is an effective alternative approach to hormonal deprivation providing simultaneously several potential benefits in terms of quality of life and cost effectiveness. Thus, in patients with non metastatic, advanced prostate cancer IAD could be used as standard treatment, while in metastatic prostate cancer IAD role still remains ambiguous.

CONCLUSIONS

Nowadays, revaluation of the gold standard of ADT in advanced prostate cancer appears essential. Recent data established that IAD should no longer be consi¬dered as investigational, since its effectiveness has been proven, especially in patients suffering from non-metastatic advanced prostate cancer.

Degarelix as an intermittent androgen deprivation therapy for one or more treatment cycles in patients with prostate cancer

BACKGROUND

Guidelines for prostate cancer treatment suggest that intermittent androgen deprivation (IAD) can be considered for certain patients.

OBJECTIVE

To evaluate the efficacy and safety of degarelix as IAD for one or more treatment cycle(s) in prostate cancer patients requiring androgen deprivation.

DESIGN, SETTING, AND PARTICIPANTS

This open-label uncontrolled multicenter study included patients with prostate-specific antigen (PSA) >4 to 50 ng/ml or PSA doubling time <24 mo. Induction included 7-mo treatment. Off-treatment period started when PSA was ≤4 ng/ml and lasted up to 24 mo based on PSA and testosterone levels. Treatment was reinitiated when PSA was >4 ng/ml.

INTERVENTION

Each induction period included a starting dose of degarelix 240mg, and thereafter 80mg once a month for 6 mo, followed by off-treatment periods.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary end point was time to PSA >4 ng/ml. Secondary end points were subgroup analysis of the primary end point, time to testosterone >0.5 and >2.2 ng/ml, quality of life (QoL), and sexual function during the first off-treatment period.

RESULTS AND LIMITATIONS

Of 213 patients in the first induction period, 191 entered the first off-treatment period, 35 patients entered the second induction, and 30 entered the second off-treatment period. Only two patients entered the third cycle. Median time to PSA >4 ng/ml and duration of first off-treatment period was 392 d each. Significant differences in time to PSA >4 ng/ml were observed between subgroups stratified by prognostic factors (previous curative treatment, cancer stage, PSA levels, and Gleason scores). Time to testosterone >0.5 and >2.2 ng/ml was 112 and 168 d, respectively. Change in QoL remained nonsignificant, and sexual function gradually improved during the off-treatment period. Adverse events were fewer during the off-treatment period and subsequent treatment cycles.

CONCLUSIONS

IAD with degarelix resulted in an improvement in sexual function commensurate with increased testosterone levels while PSA remained suppressed. The treatment for one treatment cycle or more was well tolerated.

PATIENT SUMMARY

Guidelines for prostate cancer treatment suggest that intermittent androgen deprivation (IAD) can be considered for certain patients. IAD with degarelix resulted in improved sexual function commensurate with increased testosterone levels while prostate-specific antigen remained suppressed. The treatment for one treatment cycle or more was well tolerated.

TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT00801242.

Is intermittent androgen-deprivation therapy beneficial for patients with advanced prostate cancer?

Use of intermittent androgen-deprivation therapy (IADT) in patients with prostate cancer has been evaluated in several studies, in an attempt to delay the development of castration resistance and reduce side-effects associated with ADT. However it is still not clear whether survival is adversely affected in patients treated with IADT. In this review, we explore the available data in an attempt to identify the most suitable candidate patients for IADT, and discuss factors that may inform appropriate patient stratification. ADT is first-line treatment for advanced/metastatic prostate cancer and is also recommended for use with definitive radiotherapy for high-risk localised prostate cancer. The changes in hormone levels induced by ADT can lead to short- and long-term side-effects which, although treatable in most cases, can significantly reduce the tolerability of ADT treatment. IADT has been investigated in several phase II and phase III studies in patients with locally advanced or metastatic prostate cancer, in an attempt to delay time to tumour progression and reduce the side-effect burden of ADT. In selected patient groups IADT is no less effective than continuous ADT, ameliorating the impact of ADT-related side-effects, and, to a degree, their impact on patient health-related quality of life (HRQL). Further comparative study is required, particularly in relation to HRQL and long-term complications associated with ADT.

Comparison of intermittent and continuous androgen deprivation and quality of life between patients with locally advanced and patients with metastatic prostate cancer: a post hoc analysis of the randomized FinnProstate Study VII

OBJECTIVE

The aim of the study was to compare intermittent (IAD) and continuous (CAD) androgen deprivation therapy (ADT) between locally advanced (M0) and metastatic (M1) prostate cancer, and the effect of ADT on the quality of life.

MATERIAL AND METHODS

In total, 852 men with advanced prostate cancer were enrolled to receive goserelin acetate for 24 weeks. Of these, 554 patients whose prostate-specific antigen (PSA) decreased to less than 10 ng/ml or by at least 50% (<20 ng/ml at baseline) were randomized to IAD or CAD. In the IAD arm, ADT was resumed for at least 24 weeks whenever PSA increased to greater than 20 ng/ml or above baseline.

RESULTS

Median follow-up time was 65 months. Median times from randomization to progression, death, prostate cancer death and treatment failure in M0 and M1 patients were 46.8 and 21.4, 57.6 and 40.3, 59.5 and 40.7, and 41.9 and 20.0 months, respectively (p < 0.001). No significant differences emerged between IAD and CAD. ADT showed a beneficial effect on pain, activity limitation and social functioning in M1 patients, and a deleterious effect on physical capacity in M0 patients and on sexual functioning in both groups. IAD offered extra benefit for activity limitation, social functioning and recovery of sexual functioning.

CONCLUSIONS

IAD is as efficient as CAD in treatment of locally advanced and metastatic prostate cancer. ADT improves quality of life in M1 patients, with IAD offering extra benefit.

A new protocol for intermittent androgen suppression therapy of prostate cancer with unstable saddle-point dynamics

Intermittent androgen suppression (IAS) therapy is a class of hormonal treatment for prostate cancer, in which a drug-induced androgen deprivation can reduce the population of prostate cancer cells. In IAS therapy, drugs are administrated only in on-treatment periods that are separated intermittently by off-treatment periods. The presence of off-treatment periods may be beneficial for maintaining the sensitivity of the tumor cells to androgen deprivation. Thus, IAS can be superior to continuous androgen suppression (CAS) for delaying or possibly preventing relapse of a tumor. IAS therapy usually monitors the level of serum prostate-specific antigen (PSA), which is related to the population of tumor cells. Each on-treatment period begins when the PSA level is greater than an upper threshold; treatment results in a decrease in the PSA level. The on-treatment period is suspended when the PSA level falls below a lower threshold; the PSA level then rises again until the beginning of the next on-treatment period. To determine the transitions between on- and off-treatment periods, we propose a new IAS protocol that uses a model-based estimate of the state point in the phase space of the tumor dynamics. We show that the proposed protocol is effective if, in each of the on- and off-treatment periods, the tumor dynamics exhibits a saddle-point instability accompanied by a stable manifold. Mathematical analysis reveals that tumor dynamics can be controlled in a more effective and robust manner with the proposed protocol than with conventional IAS. We also discuss the clinical feasibility of the proposed protocol as an alternative to conventional IAS therapy.

Intermittent versus continuous androgen deprivation for locally advanced, recurrent or metastatic prostate cancer: a systematic review and meta-analysis

BACKGROUND

Prostate cancer is the most common cancer in older men in the United States (USA) and Western Europe. Androgen deprivation (AD) constitutes, in most cases, the first-line of treatment for these cases. The negative impact of CAD in quality of life, secondary to the adverse events of sustained hormone deprivation, plus the costs of this therapy, motivated the intermittent treatment approach. The objective of this study is to to perform a systematic review and meta-analysis of all randomized controlled trials that compared the efficacy and adverse events profile of intermittent versus continuous androgen deprivation for locally advanced, recurrent or metastatic hormone-sensitive prostate cancer.

METHODS

Several databases were searched, including MEDLINE, EMBASE, LILACS, and CENTRAL. The endpoints were overall survival (OS), cancer-specific survival (CSS), time to progression (TTP) and adverse events. We performed a meta-analysis (MA) of the published data. The results were expressed as Hazard Ratio (HR) or Risk Ratio (RR), with their corresponding 95% Confidence Intervals (CI 95%).

RESULTS

The final analysis included 13 trials comprising 6,419 patients with hormone-sensitive prostate cancer. TTP was similar in patients who received intermittent androgen deprivation (IAD) or continuous androgen deprivation (CAD) (fixed effect: HR = 1.04; CI 95% = 0.96 to 1.14; p = 0.3). OS and CSS were also similar in patients treated with IAD or CAD (OS: fixed effect: HR = 1.02; CI 95% = 0.95 to 1.09; p = 0.56 and CSS: fixed effect: HR = 1.06; CI 95% = 0.96 to 1.18; p = 0.26).

CONCLUSION

Overall survival was similar between IAD and CAD in patients with locally advanced, recurrent or metastatic hormone-sensitive prostate cancer. Data on CSS are weak and the benefits of IAD on this outcome remain uncertain. Impact in QoL was similar for both groups, however, sexual activity scores were higher and the incidence of hot flushes was lower in patients treated with IAD.

Efficacy of intermittent androgen deprivation therapy vs conventional continuous androgen deprivation therapy for advanced prostate cancer: a meta-analysis

OBJECTIVE

To compare the efficacy of intermittent androgen deprivation therapy (IADT) vs continuous androgen deprivation therapy (CADT) for the treatment of advanced prostate cancer; we performed a meta-analysis of randomized controlled trials (RCTs), assessing the risks of disease progression, all-cause, and disease-specific mortality.

MATERIALS AND METHODS

We conducted a systematic search of several bibliographic systems to identify all RCTs of IADT in men with newly diagnosed metastatic or biochemical only prostate cancer. We abstracted outcome data, study characteristics, and participant demographics. We performed heterogeneity tests and calculated the summarized risk differences (RD) and risk ratios at 95% confidence intervals (CI), using inverse variance methods in random-effects approaches.

RESULTS

We identified 8 RCTs (N = 4664) comparing mortality between IADT and CADT. For all men combined, we observed small but nonsignificant differences in all-cause mortality (RD = 0.02, 95% CI = -0.02, 0.06), disease-specific mortality (RD = 0.04, 95% CI = -0.01, 0.08), and disease progression (RD = -0.03, 95% CI = -0.09, 0.04). Among the prespecified subgroup with histologically confirmed, newly diagnosed metastatic disease, we found no difference in overall survival (RD = 0.00, 95% CI = -0.09, 0.09).

CONCLUSION

We found no difference in overall survival, but a small increased risk in disease-specific survival for men treated with IADT relative to CADT was observed. IADT could be considered as an alternative to CADT because of better quality of life outcome. Patients should be informed of the possible risks and benefits of both therapies. More research confirming the benefits of IADT vs CADT is needed to inform treatment decisions.

Non-castrate metastatic prostate cancer: have the treatment options changed?

Over the past 7 decades androgen-deprivation therapy (ADT) has been the cornerstone of treatment for metastatic non-castrate prostate cancer (NCPC); however, the mechanisms to achieve this goal have evolved over time to include not only bilateral orchiectomy and estrogens, but also gonadotropin-releasing hormone (GnRH) agonists, antagonists, and the inclusion of androgen receptor (AR) blockade. Despite treatment with ADT, most men will progress to castrate-resistant prostate cancer (CRPC). Over the last decade many new treatment options for CRPC have emerged. These new treatments also could have a meaningful role earlier in NCPC. In this review, we outline the biologic drivers of NCPC, review current standard therapy available for NCPC, and discuss the evolving role of new therapeutics in metastatic disease.