The Efficacy and Sequencing of a Short Course of Androgen Suppression on Freedom From Biochemical Failure When Administered With Radiation Therapy for T2-T3 Prostate Cancer

Prostate Radiotherapy With Adjuvant Androgen Deprivation Therapy (ADT) Improves Metastasis-Free Survival Compared to Neoadjuvant ADT: An Individual Patient Meta-Analysis

PURPOSE

There remains a lack of clarity regarding the influence of sequencing of androgen deprivation therapy (ADT) and radiotherapy (RT) on outcomes in prostate cancer (PCa). Herein, we evaluate the optimal sequencing of ADT with prostate-directed RT in localized PCa.

METHODS

MEDLINE (1966-2018), Embase (1982-2018), ClinicalTrials.gov, and conference proceedings (1990-2018) were searched to identify randomized trials evaluating the sequencing, but not duration, of ADT with RT. Two randomized phase III trials were identified, and individual patient data were obtained: Ottawa 0101 and NRG Oncology's Radiation Therapy Oncology Group 9413. Ottawa 0101 randomly assigned patients to neoadjuvant or concurrent versus concurrent or adjuvant short-term ADT. Radiation Therapy Oncology Group 9413, a 2 × 2 factorial trial, included a random assignment of neoadjuvant or concurrent versus adjuvant short-term ADT. The neoadjuvant or concurrent ADT arms of both trials were combined into the neoadjuvant group, and the arms receiving adjuvant ADT were combined into the adjuvant group. The primary end point of this meta-analysis was progression-free survival (PFS).

RESULTS

The median follow-up was 14.9 years. Overall, 1,065 patients were included (531 neoadjuvant and 534 adjuvant). PFS was significantly improved in the adjuvant group (15-year PFS, 29% v 36%, hazard ratio [HR], 1.25 [95% CI, 1.07 to 1.47], P = .01). Biochemical failure (subdistribution HR [sHR], 1.37 [95% CI, 1.12 to 1.68], P = .002), distant metastasis (sHR, 1.40 [95% CI, 1.00 to 1.95], P = .04), and metastasis-free survival (HR, 1.17 [95% CI, 1.00 to 1.37], P = .050) were all significantly improved in the adjuvant group. There were no differences in late grade ≥ 3 gastrointestinal (2% v 3%, P = .33) or genitourinary toxicity (5% v 5%, P = .76) between groups.

CONCLUSION

The sequencing of ADT with prostate-directed RT has significant association with long-term PFS and MFS in localized PCa. Our findings favor use of an adjuvant over a neoadjuvant approach, without any increase in long-term toxicity.

Androgen deprivation therapy and radiotherapy in intermediate-risk prostate cancer: A randomised phase III trial

BACKGROUND

The role of androgen deprivation therapy (ADT) in combination with radiotherapy (RT) in intermediate-risk prostate cancer (IRPC) remains controversial, particularly in patients receiving dose-escalated RT (DERT). We compared outcomes between patients with IRPC treated with ADT and two different doses of RT vs. RT alone.

METHODS

From December 2000 to September 2010, 600 patients with IRPC were randomised to a three-arm trial consisting of 6 months of ADT plus RT 70 Gy (ADT + RT70) vs. ADT plus a DERT of 76 Gy (ADT + DERT76) vs. DERT of 76 Gy alone (DERT76). Primary end-point was biochemical failure (BF), and secondary end-points were overall survival (OS) and toxicity. RT toxicity was assessed by Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer criteria.

FINDINGS

With a median follow-up of 11.3 years (interquartile range: 10.9-11.7), patients receiving DERT76 alone, compared with patients receiving ADT + RT70 and ADT + DERT76, had higher rates of BF (32%, 18% and 14%, respectively, p < 0.001), higher rates of prostate cancer progression (12%, 4.5% and 3.3%, respectively, p = 0.001) and more deaths due to prostate cancer (6.5%, 3.0% and 1.5%, respectively, p = 0.03) with no significant difference seen between ADT + RT70 and ADT + DERT76. There was no significant difference in OS between the 3 arms. A higher dose of RT (76 Gy) increased late gastrointestinal (GI) toxicity grade ≥ II compared with lower dose (70 Gy) (16% vs 5.3%, p < 0.001) with no statistical difference for late genitourinary toxicity.

INTERPRETATION

In IRPC, the addition of 6 months of ADT to RT70 or DERT76 significantly improves BF and appears to decrease the risk of death from prostate cancer compared with DERT76 alone with no difference in OS. In the setting of IRPC, ADT plus RT 70 Gy yields effective disease control with a better GI toxicity profile. Clinicaltrials.gov#NCT00223145.

Patterns of practice of androgen deprivation therapy combined to radiotherapy in favorable and unfavorable intermediate risk prostate cancer. Results of The PROACT Survey from the French GETUG Radiation Oncology group

PURPOSE

The intermediate-risk (IR) prostate cancer (PCa) group is heterogeneous in terms of prognosis. For unfavorable or favorable IR PCa treated by radiotherapy, the optimal strategy remains to be defined. In routine practice, the physician's decision to propose hormonal therapy (HT) is controversial. The PROACT survey aimed to evaluate pattern and preferences of daily practice in France in this IR population.

MATERIALS AND METHODS

A web questionnaire was distributed to French radiotherapy members of 91 centers of the Groupe d'Etude des Tumeurs Uro-Genitales (GETUG). The questionnaire included four sections concerning: (i) the specialists who prescribe treatments and multidisciplinary decisions (MTD) validation; (ii) the definition of IR subsets of patients; (iii) radiotherapy parameters; (iv) the pattern of practice regarding cardiovascular (CV) and (iv) metabolic evaluation. A descriptive presentation of the results was used.

RESULTS

Among the 82 responses (90% of the centers), HT schedules and irradiation techniques were validated by specific board meetings in 54% and 45% of the centers, respectively. Three-fourths (76%) of the centers identified a subset of IR patients for a dedicated strategy. The majority of centers consider PSA>15 (77%) and/or Gleason 7 (4+3) (87%) for an unfavorable IR definition. Overall, 41% of the centers performed systematically a CV evaluation before HT prescription while 61% consider only CV history/status in defining the type of HT. LHRH agonists are more frequently prescribed in both favorable (70%) and unfavorable (98%) IR patients. Finally, weight (80%), metabolic profile (70%) and CV status (77%) of patients are considered for follow-up under HT.

CONCLUSION

To the best of our knowledge, this is the first survey on HT practice in IR PCa. The PROACT survey indicates that three-quarters of the respondents identify subsets of IR-patients in tailoring therapy. The CV status of the patient is considered in guiding the HT decision, its duration and type of drug.

Second-Generation Antiandrogen Therapy Radiosensitizes Prostate Cancer Regardless of Castration State through Inhibition of DNA Double Strand Break Repair

(1) Background: The combination of the first-generation antiandrogens and radiotherapy (RT) has been studied extensively in the clinical setting of prostate cancer (PCa). Here, we evaluated the potential radiosensitizing effect of the second-generation antiandrogens abiraterone acetate, apalutamide and enzalutamide. (2) Methods: Cell proliferation and agarose-colony forming assay were used to measure the effect on survival. Double strand break repair efficiency was monitored using immunofluorescence staining of γH2AX/53BP1. (3) Results: We report retrospectively a minor benefit for PCa patients received first-generation androgen blockers and RT compared to patients treated with RT alone. Combining either of the second-generation antiandrogens and 2Gy suppressed cell growth and increased doubling time significantly more than 2Gy alone, in both hormone-responsive LNCaP and castration-resistant C4-2B cells. These findings were recapitulated in resistant sub-clones to (i) hormone ablation (LNCaP-abl), (ii) abiraterone acetate (LNCaP-abi), (iii) apalutamide (LNCaP-ARN509), (iv) enzalutamide (C4-2B-ENZA), and in castration-resistant 22-RV1 cells. This radiosensitization effect was not observable using the first-generation antiandrogen bicalutamide. Inhibition of DNA DSB repair was found to contribute to the radiosensitization effect of second-generation antiandrogens, as demonstrated by a significant increase in residual γH2AX and 53BP1 foci numbers at 24h post-IR. DSB repair inhibition was further demonstrated in 22 patient-derived tumor slice cultures treated with abiraterone acetate before ex-vivo irradiation with 2Gy. (4) Conclusion: Together, these data show that second-generation antiandrogens can enhance radiosensitivity in PCa through DSB repair inhibition, regardless of their hormonal status. Translated into clinical practice, our results may help to find additional strategies to improve the effectiveness of RT in localized PCa, paving the way for a clinical trial.

Does ADT benefit unfavourable intermediate risk prostate cancer patients treated with brachytherapy boost and external beam radiotherapy? A propensity-score matched analysis

PURPOSE

To investigate the role of androgen deprivation therapy (ADT) in unfavorable intermediate risk (UIR) prostate cancer patients treated with high-dose rate (HDR) brachytherapy (BT) boost.

MATERIAL AND METHODS

Data from 326 consecutive NCCN UIR prostate cancer patients treated in a single institution from 2009 to 2016 with 15 Gy HDR-BT boost plus 37.5 Gy external beam radiotherapy (EBRT) in 15 fractions to prostate and proximal seminal vesicles were retrospectively collected. Baseline information was collected and patients receiving vs. not receiving ADT were matched using a propensity-score model. Primary endpoint was biochemical-failure-free survival (BFFS). Kaplan-Meier estimates and stratified log-rank tests (adjusting for matched design) were used to compare BFFS, castration-resistance (CRFS) and metastasis free survival (MFS) outcomes between both groups.

RESULTS

A total of 326 patients were included in the analysis of which 52 ADT patients were matched to 104 non-ADT patients in a 1:2 ratio. Median follow-up was 3.4 years and 5.5 years for ADT and non-ADT respectively. No significant baseline differences were observed. ADT was used for a median total time of 6 months (interquartile range [IQR]: 4-6) and delivered a median time of 2.7 months (IQR: 1.7-4.3) prior to HDR-BT. BFFS was significantly improved in the ADT group (stratified log-rank: p = 0.043) with 3-year and 6-year BFFS of 98% and 90% for the ADT group and 92% and 82% for the non-ADT group, respectively. No significant differences were detected for CRFS or MFS.

CONCLUSION

Short-term ADT increased BFFS in UIR prostate cancer patients treated with HDR-BT boost plus EBRT.

Combining prostate cancer radiotherapy with therapies targeting the androgen receptor axis

Background

Prostate cancer (pca) is the most common non-dermatologic cancer and the 3rd leading cause of male cancer mortality in Canada. In patients with high-risk localized or recurrent pca, management typically includes the combination of long-term androgen deprivation therapy (adt) and radiotherapy (rt). New androgen-receptor-axis targeted therapies (arats), which await validation, offer an option to intensify therapy.

Methods

In this narrative review, we report the relevant history that has supported combining adt with rt. The literature in PubMed was searched for studies involving pca and novel arats (abiraterone acetate, enzalutamide, apalutamide, darolutamide) published between 1995 and 2019. Literature discussing clinical trials in which those modalities were combined was extracted and synthesized into a combined molecular and clinical discussion. Potential treatment intensification mechanisms and rationales are explored.

Results

Early results from three phase i/ii trials demonstrated that concurrent abiraterone acetate, adt, and rt is safe, improves the extent of chemical castration, and is associated with limited treatment failures. A single in vitro study implies synergy for radiosensitization beyond that facilitated by conventional adt. Studies investigating the combination of other arats with rt are under way, including multiple phase iii trials, but short-term results are not yet available.

A pilot study of patient reported outcomes evaluating treatment related symptoms and quality of life for men receiving high dose rate brachytherapy combined with hypo-fractionated radiotherapy or hypo-fractionated radiotherapy alone for the treatment of localised prostate cancer

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PROMs have an important role to play in clinical practice.

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The radiographer-led collection of multiple PROMs is feasible.

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Monotherapy Group reported higher levels of bowel toxicity than Combination Group.

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RTOG scale was not of sufficient sensitivity and under-reported symptoms.

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A good QoL was maintained throughout treatment for both treatment groups.

Patient Reported Outcome Measures (PROMS) are useful metrics in evidence-based clinical care and translational research. Recording treatment-related symptoms and Quality of Life (QoL) can provide information in counselling patients to aid decision-making. This prospective study tested the feasibility of radiographer-led collection of multiple validated PROMS from Prostate Cancer (PCa) patients comparing High Dose Rate Brachytherapy combined with hypo-fractionated external beam radiotherapy (hEBRT) and hEBRT alone.

From June to August 2017, 20 men with localised PCa (T1-T3aN0M0) consented to participate in the study. Ten patients received combination treatment (37.5 Gray/15 fractions followed by a 15 Gray implant), and ten patients received monotherapy (60 Gray/20 fractions). PROMS were collected at four time-points (1) at baseline, (2) final fraction of hEBRT, (3) 8 weeks after commencing radiotherapy and (4) 12 weeks after commencing radiotherapy. The PROMS used were EPIC-26, IPSS, IIEFF-5 and SF-12. The difference between the two groups were tested using Mann-Whitney U test and Wilcoxon Signed-Rank Test.

All participants completed all PROMS (100% response-rate). The Monotherapy group reported a higher incidence of bowel symptoms compared to the combination group and at Week 12, EPIC-26 bowel summary score demonstrated a statistically significant difference (p = 0.005). The prevalence of erectile dysfunction increased within both groups. Maintenance of QoL was reported throughout treatment.

This small study demonstrated feasibility of radiographer-led PROMS collection by 100% completion rate. Streamlining of these tools into integrated technology applications and real time PROMS measurement has the ability to benefit patients and guide clinicians in adapting therapies based on individual need.

Practice patterns of primary EBRT with and without ADT in prostate cancer treatment

BACKGROUND

Androgen deprivation therapy (ADT) has been shown to improve survival for men with intermediate and high-risk prostate cancer undergoing external-beam radiation therapy (EBRT). Using data from a community-based prospective disease registry, we investigated usage of EBRT with or without neoadjuvant ADT.

METHODS

The CaPSURE database contains 14,863 men with prostate cancer, including 1337 men diagnosed between 1990 and 2014 with localized disease who received EBRT as primary treatment. Prostate cancer risk was calculated using the CAPRA score. Patient characteristics were compared using the Mantel-Haenszel chi-square test for trend and analysis of variance.

RESULTS

Between 1990 and 2014, 14,010 men were diagnosed with localized disease within the CaPSURE registry. Of those, 1337 underwent EBRT. Patients had a median age of 71 years. The use of ADT in addition to EBRT increased from 24% in 1990 to 60% in 1996 with a decrease seen to 47% in 2011. Men receiving ADT have differing clinical characteristics including higher PSA at diagnosis, higher Gleason grade, and higher CAPRA scores. Median ADT duration was 4 months.

CONCLUSIONS

The use of ADT in conjunction with primary EBRT has increased in frequency and duration since 1990. Men receiving ADT have higher risk characteristics than those receiving EBRT alone. There is substantial variability in use of ADT in clinical practice.

The use of Hormonal Therapy to Augment Radiation Therapy in Prostate Cancer: An Update

PURPOSE OF REVIEW

Androgen deprivation therapy (ADT) is an important adjunctive therapy to external beam radiation therapy (RT) for the definitive management of prostate cancer. The role of ADT is well-established for locally advanced or high-risk disease in conjunction with standard doses of RT, but less defined for intermediate-risk disease or with dose-escalated RT. The goal of this review is to summarize evidence evaluating the combination of ADT/RT, focusing on recent trials and current controversies as they pertain to the practicing clinician.

RECENT FINDINGS

The benefit of ADT on biochemical control is maintained with dose-escalated RT according to recently reported phase III studies. Furthermore, there is now prospective, randomized evidence to support the addition of ADT to RT in the post-prostatectomy setting. ADT continues to play an important role for prostate cancer patients receiving dose-escalated RT. Future research is needed to identify subgroups most likely to benefit from this combination.

Prostate cancer as a paradigm of multidisciplinary approach? Highlights from the Italian young radiation oncologist meeting

Aims and background

The diagnostic and therapeutic approach to prostate cancer has evolved rapidly in last decades. Young professionals need an update about these recent developments in order to improve the care of patients treated in their daily clinical practice.

Methods

On May 18, 2013, AIRO Giovani (the young section of the Italian Association of Radiation Oncology) organized a multidisciplinary meeting involving, as speakers, several young physicians from many parts of Italy actively involved in the diagnostic and therapeutic approach to prostate cancer. The meeting was specifically addressed to young physicians (radio-oncologists, urologists, medical oncologists) and presented the state-of-the-art of the diagnostic/therapeutic approach based on the latest evidence on the issue. Highlights of the congress are summarized and presented in this report.

Results

The large participation in the meeting (more than 120 participants were present) confirmed the interest of young radiation oncologists in improving their skills in prostate cancer management. The contributions of the speakers confirmed the need for regular updates, considering the promising results of recently published studies and the many new ongoing trials, on the diagnostic and therapeutic approaches to prostate cancer.

Conclusions

Multidisciplinary meetings are helpful to improve the skills of young professionals.

Neoadjuvant and adjuvant treatment in high-risk prostate cancer

INTRODUCTION

High-risk prostate cancer (HRPCa) represents a heterogeneous disease with potential risk for local and distant progression. In these patients, a multi-modal approach consisting of neoadjuvant and/or adjuvant systemic therapies has been proposed. The aim of this review is to summarize the emerging roles of neoadjuvant and adjuvant therapies in HRPCa patients. Areas covered: This review collects the most relevant phase III randomized controlled trials (RCTs) testing the effect of neoadjuvant and adjuvant systemic therapies in combination with radical prostatectomy (RP) or radiotherapy (RT) for HRPCa patients. Specifically, the review examines the benefit provided by androgen deprivation therapy (ADT), chemotherapy (CHT), and novel antiandrogen agents in this setting. A search of bibliographic databases for peer-reviewed literature was conducted. Expert commentary: Three decades of RCTs demonstrated that adjuvant ADT is fundamental in HRPCa treated with RT. Conversely, ADT and CHT did not improve the survival of HRPCa patients managed with RP. The recent introduction of novel antiandrogen agents combined with an appropriated selection of patients at risk of cancer progression, may ultimately extend the indication of neoadjuvant and adjuvant therapy in surgical- and radio-treated patients.

The Role of External-Beam Radiation Therapy in the Treatment of Clinically Localized Prostate Cancer

Background

The treatment of clinically localized prostate cancer is controversial. Options include radical prostatectomy, external-beam radiation therapy (EBRT), brachytherapy, cryotherapy, and watchful waiting.

Methods

The author reviews EBRT as treatment for clinically localized prostate cancer, with particular emphasis on the technological advances that have allowed dose escalation and fewer therapy-related side effects.

Results

Technological advances in the last two decades have significantly improved the delivery of EBRT to the prostate. This has resulted in an overall increase in the total dose that can be safely delivered to the prostate, which has led to modest improvements in biochemical outcome. An alternative approach of combining androgen suppression therapy and EBRT has also been successful in improving clinical outcomes. However, establishing the optimal therapy for prostate cancer remains controversial.

Conclusions

Recent progress has led to improvements in clinical outcomes in patients treated with EBRT for prostate cancer. It is hoped that the next decades will bring continued advances in the development of biologicals that will further improve current clinical outcomes.

The evolution of brachytherapy for prostate cancer

Brachytherapy (BT), using low-dose-rate (LDR) permanent seed implantation or high-dose-rate (HDR) temporary source implantation, is an acceptable treatment option for select patients with prostate cancer of any risk group. The benefits of HDR-BT over LDR-BT include the ability to use the same source for other cancers, lower operator dependence, and - typically - fewer acute irritative symptoms. By contrast, the benefits of LDR-BT include more favourable scheduling logistics, lower initial capital equipment costs, no need for a shielded room, completion in a single implant, and more robust data from clinical trials. Prospective reports comparing HDR-BT and LDR-BT to each other or to other treatment options (such as external beam radiotherapy (EBRT) or surgery) suggest similar outcomes. The 5-year freedom from biochemical failure rates for patients with low-risk, intermediate-risk, and high-risk disease are >85%, 69-97%, and 63-80%, respectively. Brachytherapy with EBRT (versus brachytherapy alone) is an appropriate approach in select patients with intermediate-risk and high-risk disease. The 10-year rates of overall survival, distant metastasis, and cancer-specific mortality are >85%, <10%, and <5%, respectively. Grade 3-4 toxicities associated with HDR-BT and LDR-BT are rare, at <4% in most series, and quality of life is improved in patients who receive brachytherapy compared with those who undergo surgery.

Evidence-based recommendations on androgen deprivation therapy for localized and advanced prostate cancer

Introduction

The management of prostate cancer (PC) is still evolving. Although, androgen deprivation therapy (ADT) is an established treatment option, particularly in patients with disseminated disease, important data regarding hormonal manipulation have recently emerged. The aim of this paper is to review the evidence on ADT, make recommendations and address areas of controversy associated with its use in men with PC.

Material and methods

An expert panel was convened. Areas related to the hormonal management of patients with PC requiring evidence review were identified and questions to be addressed by the panel were determined. Appropriate literature review was performed and included a search of online databases, bibliographic reviews and consultation with experts.

Results

The panel was able to provide recommendations on: 1) which patients with localised PC should receive androgen deprivation in conjunction with radiotherapy (RT); 2) what standard initial treatment should be used in metastatic hormone-naïve PC (MHNPC); 3) efficacy of androgen deprivation agents; 4) whether ADT should be continued in patients with castration resistant PC (CRPC). However, no recommendations could be made for combined ADT and very high-dose RT in patients with an intermediate-risk disease.

Conclusions

ADT remains the cornerstone of treatment for both metastatic hormone-naïve and castration-resistant PC. According to the expert panel's opinion, based on the ERG report, luteinizing hormone-releasing hormone agonists might not be equivalent but this needs to be confirmed in long-term data. The combined use of ADT and RT improves outcome and survival in men with high-risk localised disease. The benefits in patients with intermediate-risk disease, particularly those subject to escalated dose RT are controversial.

Improved survival with the addition of radiotherapy to androgen deprivation: questions answered and a review of current controversies in radiotherapy for non-metastatic prostate cancer

The contemporary standard of care for locally advanced high-risk prostate cancer includes a combination of dose-escalated radiotherapy (RT) plus androgen-deprivation therapy (ADT). However, 20 years ago, at the inception of the National Cancer Institute of Canada (NCIC) led study (NCIC Clinical Trials Group PR.3/Medical Research Council PR07/Intergroup T94-0110), the survival impact of prostate RT for high-risk disease was uncertain. Recently, Mason, Warde and colleagues presented the final results of this NCIC/MRC study (PMID: 25691677) randomizing 1,205 high-risk prostate cancer patients to ADT + RT vs. ADT alone. These updated results confirm substantial improvements with the addition of RT to ADT for the endpoints of overall survival (OS), disease-free survival (DFS), and biochemical recurrence. Close examination of subtleties of this trial's design highlight some of the most salient controversies in the field of prostate RT, including the risk-stratified roles of ADT, optimal ADT duration, and RT field design in the dose-escalated and intensity-modulated radiotherapy (IMRT) era.

Radiotherapy for high-risk prostate cancer

The combination of radiation treatment and long-term androgen deprivation therapy (ADT) has been shown in multiple clinical trials to prolong overall survival in men with high-risk prostate cancer compared with either treatment alone. New radiation technologies enable the safe delivery of high radiation doses that improve cancer control compared with lower radiation doses. Based on the results of multiple randomized trials, clinical practice guidelines for high-risk prostate cancer recommend total radiation doses of at least 75.6 Gy, with long-term (2-3 years) ADT. Ongoing research into hypofractionated radiation treatment, whole-pelvic radiation, and combinations of radiation with novel hormonal agents could further improve cancer control and survival outcomes for patients with high-risk prostate cancer.

Neo-adjuvant hormone therapy for non-metastatic prostate cancer: a systematic review and meta-analysis of 5,194 patients

Background

Neo-adjuvant hormone therapy (NHT) following radical prostatectomy (RP) or radiotherapy has been utilized in the multimodal approach to patients with intermediate- to high-risk prostate cancer (PCa). Herein, we performed a systematic review and meta-analysis of published randomized trials to evaluate the clinical efficacy of NHT.

Methods

Literatures were searched from PubMed, EMBASE, Web of Science, and Cochrane Library for comparing neo-adjuvant therapy group (NHT plus radiotherapy or radical prostatectomy) with traditional therapy (radiotherapy or prostatectomy) alone. Quality of the research was assessed on the basis of the Cochrane’s risk of bias of randomized controlled trial. Comparable information were obtained from eligible trials and assembled for meta-analysis up to 31 August 2014. RevMan 5.2 software was used for statistical analysis.

Results

Fifteen randomized controlled trials (RCTs) (total 5,194 patients) were included in this study. Meta-analysis showed there was a significant improvement in overall survival (OS) (Odds ratio (OR) = 1.51, 95% confidence interval (CI) 1.22 to 1.87, P = 0.0002), positive surgical margin (PSM) rate (OR = 0.30, 95% CI 0.24 to 0.38, P < 0.00001), and biochemical disease-free survival (bDFS) (OR = 1.95, 95% CI 1.13 to 3.39, P = 0.02), but no significant difference in disease-free survival (OR = 1.52, 95% CI 0.90 to 2.59, P = 0.12) and clinical disease-free survival (cDFS) (OR = 0.96, 95% CI 0.22 to 4.18, P = 0.95). Heterogeneity and risk of bias were observed between different studies.

Conclusions

Patients with aggressive prostate cancer would better benefit from the receipt of neo-adjuvant therapy. Physicians should make individualized treatment strategies according to adverse reactions, financial capacities, and personal wishes.

Efficacy and toxicity of external-beam radiation therapy for localised prostate cancer: a network meta-analysis

BACKGROUND

Many radiation regimens for treating prostate cancer have been used over the years, but which regimen is optimal for localised or locally advanced prostate cancer lacks consensus. We performed a network meta-analysis to identify the optimal radiation regimen.

METHODS

We systematically reviewed data from 27 randomised controlled trials and could group seven radiation regimens as follows: low- and high-dose radiation therapy (LDRT and HDRT), LDRT+ short- or long-term androgen deprivation therapy (LDRT+SADT and LDRT+LADT), HDRT+SADT, hypofractionated radiotherapy (HFRT), and HFRT+SADT. The main outcomes were overall mortality (OM), prostate-specific antigen (PSA) failure, cancer-specific mortality, and adverse events.

RESULTS

For the network meta-analysis of 27 trials, LDRT+LADT and LDRT+SADT were associated with decreased risk of OM as compared with LDRT alone as was LDRT+LADT compared with HDRT. Apart from HFRT, all other treatments were associated with decreased risk of PSA failure as compared with LDRT. HFRT+SADT was associated with decreased risk of cancer-specific mortality as compared with HFRT, LDRT+SADT, HDRT, and LDRT.

CONCLUSIONS

HFRT+SADT therapy might be the most efficacious treatment but with worst toxicity for localised or locally advanced prostate cancer, and HDRT showed excellent efficacy but more adverse events.

Current trends for the use of androgen deprivation therapy in conjunction with radiotherapy for patients with unfavorable intermediate-risk, high-risk, localized, and locally advanced prostate cancer

Androgen deprivation therapy (ADT) is now a well-established standard of care in combination with definitive radiotherapy for patients with unfavorable intermediate-risk to high-risk locally advanced prostate cancer. It is also well established that combination modality treatment with ADT and radiotherapy is superior to either of these modalities alone for the treatment of patients with high-risk locally advanced disease. Current treatment guidelines for prostate cancer in the United States are based on the estimated risk of recurrence and death. This review examines the clinical evidence underpinning the use of ADT and radiotherapy among patients with high-risk localized and locally advanced disease in the United States. This review also considers the rationale for moving from traditional luteinizing hormone-releasing hormone agonists to more recently developed gonadotrophin-releasing hormone antagonists.

Multimodality therapy for patients with high-risk prostate cancer: current status and future directions

Prostate cancer is the most commonly diagnosed cancer and second most common cause of cancer death in American men. Although high-risk disease accounts for less than 15% of diagnoses, high-risk prostate cancer patients have a cancer-specific mortality rate of 15% at 10 years. There is currently no consensus on the optimal management of high-risk disease because (1) there are different primary modalities available (ie, surgery, radiation), for which there are no randomized trials comparing efficacy; and (2) unstandardized timing of different therapies (ie, neoadjuvant v concurrent v adjuvant), which makes comparisons of efficacy problematic. Increased understanding into the mechanisms leading to the formation of advanced metastatic disease has spurred the development of agents to target these pathways. However, new questions regarding optimal management of disease arise with regard to the role of these therapies in combination with "conventional" primary modalities for earlier stage, high-risk prostate cancer patients. In this article, we review the transforming world of multimodality therapy in high-risk prostate cancer.

Randomised pilot study of dose escalation using conformal radiotherapy in prostate cancer: long-term follow-up

BACKGROUND

Radical three-dimensional conformal radiotherapy (CFRT) with initial androgen suppression (AS) is a standard management for localised prostate cancer (PC). This pilot study evaluated the role of dose escalation and appropriate target volume margin. Here, we report long-term follow-up.

METHODS

Eligible patients had T1b-T3b N0 M0 PC. After neoadjuvant AS, they were randomised to CFRT, giving (a) 64 Gy with either a 1.0- or 1.5-cm margin and (b) ±10 Gy boost to the prostate alone.

RESULTS

One hundred and twenty-six men were randomised and treated. Median follow-up was 13.7 years. The median age was 66.6 years at randomisation. Median presenting prostate-specific antigen (PSA) was 14 ng ml(-1). Sixty-four out of 126 patients developed PSA failure. Forty-nine out of 126 patients restarted AS, 34 out of 126 developed metastases and 28 out of 126 developed castrate-resistant prostate cancer (CRPC). Fifty-one out of 126 patients died; 19 out of 51 died of PC. Median overall survival (OS) was 14.4 years. Although escalated dose results were favourable, no statistically significant differences were seen between the randomised groups; PSA control (hazard ratio (HR): 0.77 (95% confidence interval (CI): 0.47-1.26)), development of CRPC (HR: 0.81 (95% CI: 0.40-1.65)), PC-specific survival (HR: 0.59 (95% CI:0.23-1.49)) and OS (HR: 0.81 (95% CI: 0.47-1.40)). There was no evidence of a difference in PSA control according to margin size (HR: 1.01 (95% CI: 0.61-1.66)).

INTERPRETATION

Long-term follow-up of this small pilot study is compatible with a benefit from dose escalation, but confirmation from larger trials is required. There was no obvious detriment using the smaller radiotherapy margin.

Androgen receptors in hormone-dependent and castration-resistant prostate cancer

In the United States, prostate cancer (PCa) is the most commonly diagnosed non-cutaneous cancer in males and the second leading cause of cancer-related death for men. The prostate is an androgen-dependent organ and PCa is an androgen-dependent disease. Androgen action is mediated by the androgen receptor (AR), a hormone activated transcription factor. The primary treatment for metastatic PCa is androgen deprivation therapy (ADT). For the most part, tumors respond to ADT, but most become resistant to therapy within two years. There is persuasive evidence that castration resistant (also termed castration recurrent) PCa (CRPC) remains AR dependent. Recent studies have shown that there are numerous factors that contribute to AR reactivation despite castrate serum levels of androgens. These include changes in AR expression and structure through gene amplification, mutation, and alternative splicing. Changes in steroid metabolism, cell signaling, and coregulator proteins are also important contributors to AR reactivation in CRPC. Most AR targeted therapies have been directed at the hormone binding domain. The finding that constitutively active AR splice variants that lack the hormone binding domain are frequently expressed in CRPC highlights the need to develop therapies that target other portions of AR. In this review, the role of AR in normal prostate, in PCa, and particularly the mechanisms for its reactivation subsequent to ADT are summarized. In addition, recent clinical trials and novel approaches to target AR are discussed.

Biochemical outcomes for patients with intermediate risk prostate cancer treated with I-125 interstitial brachytherapy monotherapy

BACKGROUND AND PURPOSE

Routine use of I-125 interstitial brachytherapy (BT) alone in intermediate risk (IR) prostate cancer is controversial. It is often combined with external beam radiotherapy (EBRT). The biochemical outcome of a large cohort of only IR disease treated with BT monotherapy is reported.

MATERIALS AND METHODS

Between 2003 and 2007, 615 patients with Memorial Sloan-Kettering Cancer Centre (MSKCC) defined IR disease (one risk factor only-T2b, or Gleason score (GS) 7, or raised initial PSA (iPSA) 10.1-20ng/ml) were treated with BT monotherapy. ASTRO (3 consecutive rises) and Phoenix (nadir plus 2) criteria defined biochemical failure. Potential prognostic factors (pre- and post-implant dosimetric indices, GS 3+4 versus 4+3, androgen deprivation therapy (ADT)) were analysed.

RESULTS

Median follow-up was 5.0years. Forty-three patients had stage T2b, 180 had raised iPSA, 392 had GS 7 disease. ADT was received by 108 patients. The 5-year biochemical no evidence of disease (bNED) rates are 87.3% (by ASTRO), 88.6% (by Phoenix). Stratification by risk factor (T2b, GS7, raised iPSA) demonstrated raised iPSA to have poorer outcome only by Phoenix criteria (p=0.0002). Other potential prognostic variables were non-significant.

CONCLUSION

Good rates of biochemical control can be achieved in the medium term with BT monotherapy in IR disease. Raised iPSA correlated with a poorer outcome.

Prostate cancer and osteoporosis

Adenocarcinoma of the prostate is one of the commonest cancers in the world. Due to a combination of earlier detection and better treatments, survival has increased dramatically. Prostate cancer itself is associated with lower bone density and increased fractures. This is compounded by the use of androgen deprivation therapy, which causes dramatic falls in circulating testosterone and estrogen, resulting in rapid falls in bone density, decreased muscle mass, and increased fracture rates. Bisphosphonates have been demonstrated to prevent and reverse this bone loss, but there are no anti-fracture data. Denosumab, a monoclonal antibody to RANKL, has recently been shown to increase bone density and reduce fracture rates. Prostate cancer also commonly metastasizes to bone where it can cause complications such as fracture and pain. Both zoledronic acid and denosumab have been demonstrated to reduce skeletal related events. Comparative studies would suggest that densosumab may have an advantage over zoledronic acid.

Short-term versus long-term hormone therapy plus radiotherapy or prostatectomy for prostate cancer: a systematic review and meta-analysis

PURPOSE

To compare the efficacy and safety of short-term versus long-term hormonotherapy (HT) plus radiotherapy (RT) or prostatectomy (RP) for prostate cancer.

METHODS

Literatures were searched from Embase, PubMed, Web of science and Cochrane Library up to October, 2012. Quality of the study was evaluated according to the Cochrane's risk of bias of randomized controlled trial (RCT); the Grading of Recommendations Assessment, Development and Evaluation System was used to rate the level of evidence. RevMan 5.1 was used for statistical analysis. Two comparisons were of interest: RT plus short-term HT versus RT plus long-term HT and RP plus short-term HT versus RP plus long-term HT. Pooled risk ratio or standardized mean differences were calculated; HT adverse reactions were descriptively evaluated.

RESULTS

Nine RCTs (total 4,743 patients) were included, 7 RCTs compared RT plus short-term HT with RT plus long-term HT, 2 RCTs compared RP plus short-term HT with RP plus long-term HT. Meta-analysis showed there was no significant difference in overall survival, disease-free survival and PSA level before RP; long-term was superior to short-term hormonotherapy in biochemical failure rate, clinical progression rate, prostate cancer-specific mortality, positive surgical margin rate and prostate volume before RP. Systematic review demonstrated adverse events caused by the increased length of HT were more common.

CONCLUSIONS

Long-term HT plus RT showed a trend toward improved overall survival; long-term HT plus RP declined positive surgical margin rate and prostate volume before RP. So, long-term HT may benefit more, but it did not significantly improve the patients' overall survival, and the adverse reactions are inevitable.

Castration therapy results in decreased Ku70 levels in prostate cancer

PURPOSE

Neoadjuvant castration improves response to radiotherapy of prostate cancer. Here, we determine whether castration therapy impairs nonhomologous end-joining (NHEJ) repair of DNA double-strand breaks (DSB) by downregulating Ku70 protein expression.

EXPERIMENTAL DESIGN

Twenty patients with locally advanced prostate cancer were enrolled, and 6 to 12 needle core biopsy specimens were taken from the prostate of each patient before treatment. Bilateral orchidectomy was conducted in eight patients and 12 patients were treated with a GnRH agonist. After castration, two to four similar biopsies were obtained, and the levels of Ku70 and γ-H2AX foci were determined by immunofluorescence in verified cancer tissues.

RESULTS

We observed that the androgen receptor binds directly to Ku70 in prostate tissue. We also found a reduction of the Ku70 protein levels in the cell nuclei in 12 of 14 patients (P < 0.001) after castration. The reduction in Ku70 expression correlated significantly with decreased serum prostate-specific antigen (PSA) levels after castration, suggesting that androgen receptor activity regulates Ku70 protein levels in prostate cancer tissue. Furthermore, a significant correlation between the reductions of Ku70 after castration versus changes induced of castration of γ-H2AX foci could be seen implicating a functional linkage of decreased Ku70 levels and impaired DNA repair.

CONCLUSIONS

Castration therapy results in decreased levels of the Ku70 protein in prostate cancer cells. Because the Ku70 protein is essential for the NHEJ repair of DSBs and its downregulation impairs DNA repair, this offers a possible explanation for the increased radiosensitivity of prostate cancer cells following castration.

Androgen deprivation therapy toxicity and management for men receiving radiation therapy

Androgen deprivation therapy is commonly used in combination with radiotherapy as part of the definitive treatment for men with clinically localized and locally advanced prostate cancer. Androgen deprivation has been associated with a wide range of iatrogenic effects impacting a variety of body systems including metabolic, musculoskeletal, cardiovascular, neurocognitive, and sexual. This review aims to provide the radiation oncology community with the knowledge to monitor and manage androgen deprivation therapy toxicity in an effort to provide the highest level of care for patients and to minimize the iatrogenic effects of androgen deprivation as much as possible.

High-dose conformal radiotherapy reduces prostate cancer-specific mortality: results of a meta-analysis

PURPOSE

To determine in a meta-analysis whether prostate cancer-specific mortality (PCSM), biochemical or clinical failure (BCF), and overall mortality (OM) in men with localized prostate cancer treated with conformal high-dose radiotherapy (HDRT) are better than those in men treated with conventional-dose radiotherapy (CDRT).

METHODS AND MATERIALS

The MEDLINE, Embase, CANCERLIT, and Cochrane Library databases, as well as the proceedings of annual meetings, were systematically searched to identify randomized, controlled studies comparing conformal HDRT with CDRT for localized prostate cancer.

RESULTS

Five randomized, controlled trials (2508 patients) that met the study criteria were identified. Pooled results from these randomized, controlled trials showed a significant reduction in the incidence of PCSM and BCF rates at 5 years in patients treated with HDRT (p = 0.04 and p < 0.0001, respectively), with an absolute risk reduction (ARR) of PCSM and BCF at 5 years of 1.7% and 12.6%, respectively. Two trials evaluated PCSM with 10 years of follow up. The pooled results from these trials showed a statistical benefit for HDRT in terms of PCSM (p = 0.03). In the subgroup analysis, trials that used androgen deprivation therapy (ADT) showed an ARR for BCF of 12.9% (number needed to treat = 7.7, p < 0.00001), whereas trials without ADT had an ARR of 13.6% (number needed to treat = 7, p < 0.00001). There was no difference in the OM rate at 5 and 10 years (p = 0.99 and p = 0.11, respectively) between the groups receiving HDRT and CDRT.

CONCLUSIONS

This meta-analysis is the first study to show that HDRT is superior to CDRT in preventing disease progression and prostate cancer-specific death in trials that used conformational technique to increase the total dose. Despite the limitations of our study in evaluating the role of ADT and HDRT, our data show no benefit for HDRT arms in terms of BCF in trials with or without ADT.

Androgen deprivation therapy: past, present and future

Since Huggins and Hodges demonstrated the responsiveness of prostate cancer to androgen deprivation therapy (ADT), androgen-suppressing strategies have formed the cornerstone of management of advanced prostate cancer. Approaches to ADT have included orchidectomy, oestrogens, luteinizing hormone-releasing hormone (LHRH) agonists, anti-androgens and more recently the gonadotrophin-releasing hormone antagonists. The most extensively studied antagonist, degarelix, avoids the testosterone surge and clinical flare associated with LHRH agonists, offering more rapid PSA and testosterone suppression, improved testosterone control and improved PSA progression-free survival compared with agonists. The clinical profile of degarelix appears to make it a particularly suitable therapeutic option for certain subgroups of patients, including those with metastatic disease, high baseline PSA (>20 ng/mL) and highly symptomatic disease. As well as forming the mainstay of treatment for advanced prostate cancer, ADT is increasingly used in earlier disease stages. While data from clinical trials support the use of ADT neoadjuvant/adjuvant to radiotherapy for locally advanced or high-risk localized prostate cancer, it remains to be established whether specific ADT classes/agents provide particular benefits in this clinical setting.

Androgen deprivation therapy in combination with radiotherapy for high-risk clinically localized prostate cancer

Androgen deprivation therapy (ADT) has remained the main therapeutic option for patients with advanced prostate cancer (PCa) for about 70 years. Several reports and our findings revealed that aggressive PCa can occur under a low dihydrotestosterone (DHT) level environment where the PCa of a low malignancy with high DHT dependency cannot easily occur. Low DHT levels in the prostate with aggressive PCa are probably sufficient to propagate the growth of the tumor, and the prostate with aggressive PCa can produce androgens from the adrenal precursors more autonomously than that with non-aggressive PCa does under the low testosterone environment with testicular suppression. In patients treated with ADT the pituitary-adrenal axis mediated by adrenocorticotropic hormone has a central role in the regulation of androgen synthesis. Several experimental studies have confirmed the potential benefits from the combination of ADT with radiotherapy (RT). A combination of external RT with short-term ADT is recommended based on the results of phase III randomized trials. In contrast, the combination of RT plus 6 months of ADT provides inferior survival as compared with RT plus 3 years of ADT in the treatment of locally advanced PCa. Notably, randomized trials included patients with diverse risk groups treated with older RT modalities, a variety of ADT scheduling and duration and, importantly, suboptimal RT doses. The use of ADT with higher doses of RT or newer RT modalities has to be properly assessed.

Androgenic suppression combined with radiotherapy for the treatment of prostate adenocarcinoma: a systematic review

BACKGROUND

Locally advanced prostate cancer is often associated with elevated recurrence rates. Despite the modest response observed, external-beam radiotherapy has been the preferred treatment for this condition. More recent evidence from randomised trials has demonstrated clinical benefit with the combined use of androgen suppression in such cases. The aim of this meta-analysis is to compare the combination of distinct hormone therapy modalities versus radiotherapy alone for overall survival, disease-free survival and toxicity.

METHODS

Databases (MEDLINE, EMBASE, LILACS, Cochrane databases and ClinicalTrials.gov) were scanned for randomised clinical trials involving radiotherapy with or without androgen suppression in local prostate cancer. The search strategy included articles published until October 2011. The studies were examined and the data of interest were plotted for meta-analysis. Survival outcomes were reported as a hazard ratio with corresponding 95% confidence intervals.

RESULTS

Data from ten trials published from 1988 to 2011 were included, comprising 6555 patients. There was a statistically significant advantage to the use of androgen suppression, in terms of both overall survival and disease free survival, when compared to radiotherapy alone. The use of long-term goserelin (up to three years) was the strategy providing the higher magnitude of clinical benefit. In contrast to goserelin, there were no trials evaluating the use of other luteinizing hormone-releasing hormone (LHRH) analogues as monotherapy. Complete hormonal blockade was not shown to be superior to goserelin monotherapy.

CONCLUSIONS

Based on the findings of this systematic review, the evidence supports the use of androgen suppression with goserelin monotherapy as the standard treatment for patients with prostate cancer treated with radiotherapy, which are at high risk of recurrence or metastases.

ACR Appropriateness Criteria® definitive external beam irradiation in stage T1 and T2 prostate cancer

PURPOSE

: External beam radiation therapy is a standard of care treatment for men who present with clinically localized (T1-T2) prostate cancer. The purpose of this review was to provide clarification on the appropriateness criteria and management considerations for the treatment of prostate cancer with external beam radiation therapy.

METHODS

: A panel consisting of physicians with expertise on prostate cancer was assembled and provided with a number of clinical scenarios for consensus treatment and management guidelines. Prostate cancer patient vignettes were presented along with specific management recommendations based on an extensive review of the modern external beam radiotherapy literature. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances, where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

RESULTS

: Modern external beam radiation therapy series demonstrate favorable biochemical control rates for patients with localized prostate cancer. Morbidity profiles are also favorable and it is clear that this is enhanced by modern techniques like 3-dimensional conformal radiation therapy and intensity-modulated radiation therapy. An active area of investigation is evaluating the use of hypofractionated dosing.

CONCLUSIONS

: Continued investigation to refine patient selection, external beam radiation technology application, and alternative dosing schedules should result in further improvements in biochemical outcome and decreased morbidity with external beam radiation treatment for localized prostate cancer.

Risk stratification in the hormonal treatment of patients with prostate cancer

Prostate cancer (PCa) is the most common type of cancer found in American men, other than skin cancer. The American Cancer Society estimates that there will be 186,320 new cases of prostate cancer in the United States in 2008. About 28,660 men will die of this disease this year and PCa remains the second-leading cause of cancer death in men. One in six men will get PCa during his lifetime and one in 35 will die of the disease. Today, more than 2 million men in the United States who have had PCa are still alive. The death rate for PCa continues to decline, chiefly due to early detection and treatment, and improved salvage therapy such as hormone therapy (HT). HT continues to be a mainstay for primary-recurrent PCa and locally-advanced PCa. However, HT is associated with many undesirable side effects including sexual dysfunction, osteoporosis and hot flashes, all of which can lead to decreased quality of life (QOL). These risks are seen in both long- and short-term HT regimens. Additionally, research in recent years has revealed trends related to clinico pathological variables and their predictive ability in HT outcomes. Awareness of the potential adverse effects, the risks associated with HT and the prognostic ability of clinical and pathological variables is important in determining optimal therapy for individual patients. A rigorous evaluation of the current scientific literature associated with HT was conducted with the goal of identifying the most favorable balance of benefits and risks associated with HT.

Androgen deprivation therapy and definitive radiotherapy for prostate cancer

Adjuvant androgen deprivation therapy (ADT) improves outcomes of patients receiving definitive radiotherapy (RT) for local-regionally advanced prostate cancer. However, patients in most randomized trials had more advanced disease than observed in many practices and were treated with suboptimal RT doses. Although data are conflicting, long-term ADT likely has adverse side-effects in patients with comorbidities. We recommend 6 months of ADT monotherapy with gonadotropin-releasing hormone agonist and RT for patients with high-risk prostate cancer (≥T2c, Gleason Score 8 to 10, and/or prostate-specific antigen ≥20 ng/mL) with minimal or no comorbidities. Adjuvant ADT for unfavorable intermediate-risk patients with a Gleason Score of 4+3=7 is also reasonable.

Treatment for intermediate and high-risk prostate cancer: controversial issues and the role of hyperthermia

For patients affected by intermediate- and high-risk prostate cancer, a single local therapy is not enough, and a more aggressive treatment, such as androgen suppression therapy (AST) and pelvic irradiation, is indicated. Biochemical disease-free survival (bDFS) and overall survival (OS) improve in intermediate- and high-risk prostate cancer using radiotherapy (RT) combined with AST as compared with the RT alone. Hyperthermia (HT), combined with RT for the treatment of prostate cancer with intermediate- and high-risk, has been defined as "promising". In the development of new strategies, the reduction of short and long-term treatment related toxicity is of primary importance. Quality of Life (QoL) has been previously investigated and the authors concluded that HT does not negatively impact QoL in patients treated with radiation and HT. The use of HT in treating advanced prostate cancer has been reported by many centres; several studies suggest the feasibility of HT added to conventional RT. In intermediate- and high-risk prostate cancer, the combination of RT plus a long-term androgen suppression provides good results in terms of OS and QoL. HT, improving the anti-cancer effects of irradiation, as demonstrated by experimental in vitro and in vivo studies, could increase the outcome in the treatment of locally advanced prostate tumours without adding toxicity. A randomised phase III trial comparing RT-AST combined treatment plus/minus HT is needed to demonstrate the efficacy of HT.

Combining radiation therapy and androgen deprivation for localized prostate cancer-a critical review

Interest has been increasing in the use of androgen deprivation therapy (ADT) combined with radiation therapy (RT) in the management of localized prostate cancer. Preclinical studies have provided some rationale for the use of this combination. In patients with high-risk disease, the benefit of a combined approach, with the addition of adjuvant hormonal therapy, is supported by results of randomized trials. In contrast, for patients with low-risk disease, there is no obvious therapeutic advantage except for cytoreduction. The usefulness of short-term hormonal therapy in association with rt for intermediate-risk patients is still debatable, particularly in the context of doseescalated RT. The optimal timing and duration of ADT, in the neoadjuvant and adjuvant settings alike, are still under investigation. In view of the potential side effects with ADT, further studies are being performed to better identify subsets of patients who will definitely benefit from this therapy in combination with rt.

Impact of hormonal treatment duration in combination with radiotherapy for locally advanced prostate cancer: meta-analysis of randomized trials

Background

Hormone therapy plus radiotherapy significantly decreases recurrences and mortality of patients affected by locally advanced prostate cancer. In order to determine if difference exists according to the hormonal treatment duration, a literature-based meta-analysis was performed.

Methods

Relative risks (RR) were derived through a random-effect model. Differences in primary (biochemical failure, BF; cancer-specific survival, CSS), and secondary outcomes (overall survival, OS; local or distant recurrence, LR/DM) were explored. Absolute differences (AD) and the number needed to treat (NNT) were calculated. Heterogeneity, a meta-regression for clinic-pathological predictors and a correlation test for surrogates were conducted.

Results

Five trials (3,424 patients) were included. Patient population ranged from 267 to 1,521 patients. The longer hormonal treatment significantly improves BF (with significant heterogeneity) with an absolute benefit of 10.1%, and a non significant trend in CSS. With regard to secondary end-points, the longer hormonal treatment significantly decrease both the LR and the DM with an absolute difference of 11.7% and 11.5%. Any significant difference in OS was observed. None of the three identified clinico-pathological predictors (median PSA, range 9.5-20.35, Gleason score 7-10, 27-55% patients/trial, and T3-4, 13-77% patients/trial), did significantly affect outcomes. At the meta-regression analysis a significant correlation between the overall treatment benefit in BF, CSS, OS, LR and DM, and the length of the treatment was found (p≤0.03).

Conclusions

Although with significant heterogeneity (reflecting different patient' risk stratifications), a longer hormonal treatment duration significantly decreases biochemical, local and distant recurrences, with a trend for longer cancer specific survival.

A randomized trial (Irish clinical oncology research group 97-01) comparing short versus protracted neoadjuvant hormonal therapy before radiotherapy for localized prostate cancer

PURPOSE

To examine the long-term outcomes of a randomized trial comparing short (4 months; Arm 1) and long (8 months; Arm 2) neoadjuvant hormonal therapy before radiotherapy for localized prostate cancer.

METHODS AND MATERIALS

Between 1997 and 2001, 276 patients were enrolled and the data from 261 were analyzed. The stratification risk factors were prostate-specific antigen level >20 ng/mL, Gleason score≥7, and Stage T3 or more. The intermediate-risk stratum had one factor and the high-risk stratum had two or more. Staging was done from the bone scan and computed tomography findings. The primary endpoint was biochemical failure-free survival.

RESULTS

The median follow-up was 102 months. The overall survival, biochemical failure-free survival. and prostate cancer-specific survival did not differ significantly between the two treatment arms, overall or at 5 years. The cumulative probability of overall survival at 5 years was 90% (range, 87-92%) in Arm 1 and 83% (range, 80-86%) in Arm 2. The biochemical failure-free survival rate at 5 years was 66% (range, 62-71%) in Arm 1 and 63% (range, 58-67%) in Arm 2.

CONCLUSION

No statistically significant difference was found in biochemical failure-free survival between 4 months and 8 months of neoadjuvant hormonal therapy before radiotherapy for localized prostate cancer.