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Background: The optimal duration of androgen suppression for men with locally advanced prostate cancer receiving radiotherapy with curative intent is yet to be defined. Zoledronic acid is effective in preventing androgen suppression-induced bone loss, but its role in preventing castration-sensitive bone metastases in locally advanced prostate cancer is unclear. The RADAR trial assessed whether the addition of 12 months of adjuvant androgen suppression, 18 months of zoledronic acid, or both, can improve outcomes in men with locally advanced prostate cancer who receive 6 months of androgen suppression and prostatic radiotherapy. This report presents 10-year outcomes from this trial.Methods: For this randomised, phase 3, 2 × 2 factorial trial, eligible men were 18 years or older with locally advanced prostate cancer (either T2b-4, N0 M0 tumours or T2a, N0 M0 tumours provided Gleason score was ≥7 and baseline prostate-specific antigen [PSA] concentration was ≥10 μg/L). We randomly allocated participants in a 2 × 2 factorial design by computer-generated randomisation (using the minimisation technique, and stratified by centre, baseline PSA concentration, clinical tumour stage, Gleason score, and use of a brachytherapy boost) in a 1:1:1:1 ratio to four treatment groups. Patients in the control group received 6 months of neoadjuvant androgen suppression with leuprorelin (22·5 mg every 3 months, intramuscularly) and radiotherapy alone (short-term androgen suppression [STAS]); this treatment was either followed by another 12 months of adjuvant androgen suppression with leuprorelin (22·5 mg every 3 months, intramuscularly; intermediate-term androgen suppression [ITAS]), or accompanied by 18 months of zoledronic acid (4 mg every 3 months, intravenously) starting at randomisation (STAS plus zoledronic acid), or both (ITAS plus zoledronic acid). All patients received radiotherapy to the prostate and seminal vesicles, starting from the end of the fifth month of androgen suppression; dosing options were 66, 70, and 74 Gy in 2-Gy fractions per day, or 46 Gy in 2-Gy fractions followed by a high-dose-rate brachytherapy boost dose of 19·5 Gy in 6·5-Gy fractions. Treatment allocation was open label. The primary endpoint was prostate cancer-specific mortality and was analysed according to intention-to-treat using competing-risks methods. The trial is closed to follow-up and this is the final report of the main endpoints. This trial is registered with ClinicalTrials.gov, number NCT00193856.Findings: Between Oct 20, 2003, and Aug 15, 2007, 1071 men were enrolled and randomly assigned to STAS (n=268), ITAS (n=268), STAS plus zoledronic acid (n=268), and ITAS plus zoledronic acid (n=267). Median follow-up was 10·4 years (IQR 7·9-11·7). At this 10-year follow-up, no interactions were observed between androgen suppression and zoledronic acid so the treatment groups were collapsed to compare treatments according to duration of androgen suppression: 6 months of androgen suppression plus radiotherapy (6AS+RT) versus 18 months of androgen suppression plus radiotherapy (18AS+RT) and to compare treatments according to whether or not patients received zoledronic acid. The total number of deaths was 375 (200 men receiving 6AS+RT and 175 men receiving 18AS+RT), of which 143 (38%) were attributable to prostate cancer (81 men receiving 6AS+RT and 62 men receiving 18AS+RT). When analysed by duration of androgen suppression, the adjusted cumulative incidence of prostate cancer-specific mortality was 13·3% (95% CI 10·3-16·0) for 6AS+RT versus 9·7% (7·3-12·0) for 18AS+RT, representing an absolute difference of 3·7% (95% CI 0·3-7·1; sub-hazard ratio [sHR] 0·70 [95% CI 0·50-0·98], adjusted p=0·035). The addition of zoledronic acid did not affect prostate cancer-specific mortality; the adjusted cumulative incidence of prostate cancer-specific mortality was 11·2% (95% CI 8·7-13·7) with zoledronic acid vs 11·7% (9·2-14·1) without, representing an absolute difference of -0·5% (95% CI -3·8 to 2·9; sHR 0·95 [95% CI 0·69-1·32], adjusted p=0·78). Although safety analysis was not prespecified for this 10-year analysis, one new serious adverse event (osteonecrosis of the mandible, in a patient who received 18 months of androgen suppression plus zoledronic acid) occurred since our previous report, bringing the total number of cases of this serious adverse event to three (<1% out of 530 patients who received zoledronic acid evaluated for safety) and the total number of drug-related serious adverse events to 12 (1% out of all 1065 patients evaluable for safety). No treatment-related deaths occurred during the study.Interpretation: 18 months of androgen suppression plus radiotherapy is a more effective treatment option for locally advanced prostate cancer than 6 months of androgen suppression plus radiotherapy, but the addition of zoledronic acid to this treatment regimen is not beneficial. Evidence from the RADAR and French Canadian Prostate Cancer Study IV trials suggests that 18 months of androgen suppression with moderate radiation dose escalation is an effective but more tolerable option than longer durations of androgen suppression for men with locally advanced prostate cancer including intermediate and high risk elements.Funding: National Health and Medical Research Council of Australia, Novartis Pharmaceuticals Australia, AbbVie Pharmaceuticals Australia, New Zealand Health Research Council, New Zealand Cancer Society, Cancer Standards Institute New Zealand, University of Newcastle (Australia), Hunter Medical Research Institute, Calvary Mater Newcastle Radiation Oncology Fund, and Maitland Cancer Appeal. [ABSTRACT FROM AUTHOR]

Summary Background We investigated whether 18 months of androgen suppression plus radiotherapy, with or without 18 months of zoledronic acid, is more effective than 6 months of neoadjuvant androgen suppression plus radiotherapy with or without zoledronic acid. Methods We did an open-label, randomised, 2 × 2 factorial trial in men with locally advanced prostate cancer (either T2a N0 M0 prostatic adenocarcinomas with prostate-specific antigen [PSA] ≥10 μg/L and a Gleason score of ≥7, or T2b–4 N0 M0 tumours regardless of PSA and Gleason score). We randomly allocated patients by computer-generated minimisation—stratified by centre, baseline PSA, tumour stage, Gleason score, and use of a brachytherapy boost—to one of four groups in a 1:1:1:1 ratio. Patients in the control group were treated with neoadjuvant androgen suppression with leuprorelin (22·5 mg every 3 months, intramuscularly) for 6 months (short-term) and radiotherapy alone (designated STAS); this procedure was either followed by another 12 months of androgen suppression with leuprorelin (intermediate-term; ITAS) or accompanied by 18 months of zoledronic acid (4 mg every 3 months for 18 months, intravenously; STAS plus zoledronic acid) or by both (ITAS plus zoledronic acid). The primary endpoint was prostate cancer-specific mortality. This analysis represents the first, preplanned assessment of oncological endpoints, 5 years after treatment. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov , number NCT00193856 . Findings Between Oct 20, 2003, and Aug 15, 2007, 1071 men were randomly assigned to STAS (n=268), STAS plus zoledronic acid (n=268), ITAS (n=268), and ITAS plus zoledronic acid (n=267). Median follow-up was 7·4 years (IQR 6·5–8·4). Cumulative incidences of prostate cancer-specific mortality were 4·1% (95% CI 2·2–7·0) in the STAS group, 7·8% (4·9–11·5) in the STAS plus zoledronic acid group, 7·4% (4·6–11·0) in the ITAS group, and 4·3% (2·3–7·3) in the ITAS plus zoledronic acid group. Cumulative incidence of all-cause mortality was 17·0% (13·0–22·1), 18·9% (14·6–24·2), 19·4% (15·0–24·7), and 13·9% (10·3–18·8), respectively. Neither prostate cancer-specific mortality nor all-cause mortality differed between control and experimental groups. Cumulative incidence of PSA progression was 34·2% (28·6–39·9) in the STAS group, 39·6% (33·6–45·5) in the STAS plus zoledronic acid group, 29·2% (23·8–34·8) in the ITAS group, and 26·0% (20·8–31·4) in the ITAS plus zoledronic acid group. Compared with STAS, no difference was noted in PSA progression with ITAS or STAS plus zoledronic acid; however, ITAS plus zoledronic acid reduced PSA progression (sub-hazard ratio [SHR] 0·71, 95% CI 0·53–0·95; p=0·021). Cumulative incidence of local progression was 4·1% (2·2–7·0) in the STAS group, 6·1% (3·7–9·5) in the STAS plus zoledronic acid group, 1·5% (0·5–3·7) in the ITAS group, and 3·4% (1·7–6·1) in the ITAS plus zoledronic acid group; no differences were noted between groups. Cumulative incidences of bone progression were 7·5% (4·8–11·1), 14·6% (10·6–19·2), 8·4% (5·5–12·2), and 7·6% (4·8–11·2), respectively. Compared with STAS, STAS plus zoledronic acid increased the risk of bone progression (SHR 1·90, 95% CI 1·14–3·17; p=0·012), but no differences were noted with the other two groups. Cumulative incidence of distant progression was 14·7% (10·7–19·2) in the STAS group, 17·3% (13·0&#82 [ABSTRACT FROM AUTHOR]

Abstract: Purpose: In the TROG 96.01 trial 6month neo-adjuvant androgen suppression (NAS) and radiotherapy (RT) for locally advanced prostate cancer prevented distant progressions (DPs) when compared to RT alone, but 3months did not. We ask why? Methods: Between 1996 and 2000, 802 men with T2-4 N0 M0 prostate cancers received RT alone (0month NAS) to 66Gy, 3months or 6months NAS before RT. Interval hazards and cumulative incidences of DP were compared using competing risks methodology. Results: In the first 4 follow-up years 39, 40 and 26 DPs were diagnosed in subjects treated with 0, 3 and 6month NAS, respectively. Compared with 0month, significant reductions in PSA doubling time in subjects with DP occurred following 3month NAS (p =0.01), but a significant reduction (p =0.01) and a near significant delay in DPs (p =0.06) occurred after 6month NAS. Subsequently 25, 20 and 11 DPs occurred in the three trial arms. After early secondary therapy for PSA or local progression 34, 19 and 12 DPs were diagnosed after median delays of almost 4years. Conclusions: The data are consistent with the failure of 3month NAS to prevent the progression of sub-clinical metastatic deposits already present before treatment. [Copyright &y& Elsevier]

Summary: Background: Adjuvant androgen suppression and bisphosphonates with escalating doses of radiotherapy might improve efficacy outcomes in men with locally advanced prostate cancer. In this study, we investigated whether these treatments had a detrimental effect on patient-reported-outcome (PRO) scores. Methods: We undertook a phase 3 trial with a 2×2 factorial design in 23 centres in Australia and New Zealand in men with non-metastatic adenocarcinoma of the prostate (stage T2b–4 or T2a, Gleason score ≥7, and baseline prostate-specific antigen concentration [PSA] ≥10 μg/L), and without previous lymph node or systemic metastases or comorbidities that could reduce life expectancy to less than 5 years. The men were randomly assigned in a 1:1:1:1 ratio to 6 months of neoadjuvant (short-term) androgen suppression (STAS) with leuprorelin (22·5 mg every 3 months, intramuscularly) or an additional 12 months (intermediate-term androgen suppression [ITAS]) of leuprorelin with or without 18 months of zoledronic acid (4 mg every 3 months, intravenously). Study drug administration commenced at randomisation after which radiotherapy started within the fifth month in all groups. Treatment allocation was open-label, and computer-generated randomisation, stratified by centre, baseline concentrations of PSA, clinical stage of the tumour, Gleason score, and use of a brachytherapy boost, was done by use of the minimisation technique. PRO scores were calculated from European Organization for Research and Treatment of Cancer quality-of-life and prostate-specific quality-of-life module questionnaires and compared with multiple regression models at baseline, and end of radiotherapy, and 18 months and 36 months according to group and radiation dose. The trial is ongoing and the primary endpoint, prostate-cancer-specific mortality, will be reported in 2014. This study is the final report of PRO scores (a secondary endpoint). Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00193856. Findings: 1071 men were randomly assigned to STAS (n=268), STAS plus zoledronic acid (n=268), ITAS (n=268), and ITAS plus zoledronic acid (n=267). At the end of radiotherapy, significant detrimental changes in PRO scores (p<0·01) occurred in all groups. There were no significant differences in global health status between groups at any timepoint. At 18 months, PROs that were significantly worse in the ITAS groups when compared with STAS were hormone-treatment-related symptoms (HTRS; STAS, 10·20 [95% CI 8·66–11·75]; ITAS, 17·36 [13·63–21·08], p<0·01; and ITAS plus zoledronic acid, 19·14 [15·43–22·85], p<0·01), sexual activity (STAS, 26·38 [23·50–29·27]; ITAS, 14·40 [7·44–21·36], p<0·01; and ITAS plus zoledronic acid, 16·34 [9·39–23·28], p<0·01), social function (STAS, 90·31 [87·89–92·73]; ITAS, 87·35 [81·52–93·18], p=0·09; and ITAS plus zoledronic acid, 83·66 [77·85–89·48], p<0·01), fatigue (STAS, 17·05 [14·58–19·51]; ITAS 24·52 [18·58–30·46], p<0·01; and ITAS plus zoledronic acid, 24·26 [18·33–30·18], p<0·01), and financial problems (STAS, 3·39 [1·29–5·48]; ITAS, 8·97 [3·92–14·02], p<0·01; and ITAS plus zoledronic acid, 8·92 [3·89–13·96], p<0·01). With the exception of HTRS, in which marginal differences remained, persisting significant differences disappeared by 36 months. Other factors associated with significant detrimental changes in PRO scores were a brachytherapy boost, incomplete testosterone and haemoglobin recoveries, age, and smoking. Interpretation: Compared with 6 months of androgen suppression, 18 months of androgen suppression causes additional detrimental changes at the 18 month follow-up in some PRO scores but not in global quality-of-life scores. However, with the exception of HTRS, these differences resolved by 36 months. The use of zoledronic acid every 3 months over 18 months does not result in additional detrimental changes, but the use of a brachytherapy boost to achieve radiation dose escalation in the prostate can adversely affect emotional function and financial problems. Funding: National Health and Medical Research Council of Australia, Novartis Pharmaceuticals Australia, Abbott Pharmaceuticals Australia, New Zealand Health Research Council, New Zealand Cancer Society, University of Newcastle (Australia), Hunter Medical Research Institute, Calvary Mater Radiation Oncology Fund, and Maitland Cancer Appeal. [Copyright &y& Elsevier]

Abstract: Background: The RADAR trial determines whether adjuvant androgen suppression, bisphosphonates and radiation dose escalation for localised prostate cancer (PC) may improve oncologic outcomes. This study examines whether these measures increase rectal and urinary dysfunction and are secondary trial endpoints. Methods: Using a 2×2 factorial trial design men with locally advanced PC were randomly allocated 6months i.m. leuprorelin prior to radiotherapy either alone or followed by 12months i.m. leuprorelin. These two groups received 18months i.v. zoledronic acid (Z) commencing at randomisation or no further treatment. Radiotherapy dose was escalated in a regulated way using external beam techniques (EBRT) or by a high dose rate brachytherapy (HDRB) boost. Prevalence rates of rectal and urinary dysfunctional symptoms were compared at baseline, the end of RT, 18 and 36months according to treatment arm, dose and technique using multiple regression models. Results: Between 2003 and 2007, 1071 men were randomly allocated and eligible for inclusion in this study. No persistent differences in rectal or urinary dysfunction were attributable to treatment arm or to increasing EBRT dose. However following HDRB statistical increases (p <0.001) in urinary dysfunction were measured using the EORTC PR25 instrument at 18 and 36months. Conclusion: Adjuvant androgen suppression, bisphosphonates and increasing EBRT dose did not increase rectal or urinary dysfunction in this trial. However dose escalation using HDRB increased urinary dysfunction. [Copyright &y& Elsevier]

Purpose: We sought to compare the prognostic value of early prostate-specific antigen (PSA) test-based variables for the 802 eligible patients treated in the Trans-Tasman Radiation Oncology Group 96.01 randomized trial. Methods and Materials: Patients in this trial had T2b, T2c, T3, and T4 N0 prostate cancer and were randomized to 0, 3, or 6 months of neoadjuvant androgen deprivation therapy (NADT) prior to and during radiation treatment at 66 Gy to the prostate and seminal vesicles. The early PSA test-based variables evaluated were the pretreatment initial PSA (iPSA) value, PSA values at 2 and 4 months into NADT, the PSA nadir (nPSA) value after radiation in all patients, and PSA response signatures in men receiving radiation. Comparisons of endpoints were made using Cox models of local progression-free survival, distant failure-free survival, biochemical failure-free survival, and prostate cancer-specific survival. Results: The nPSA value was a powerful predictor of all endpoints regardless of whether NADT was given before radiation. PSA response signatures also predicted all endpoints in men treated by radiation alone. iPSA and PSA results at 2 and 4 months into NADT predicted biochemical failure-free survival but not any of the clinical endpoints. nPSA values correlated with those of iPSA, Gleason grade, and T stage and were significantly higher in men receiving radiation alone than in those receiving NADT. Conclusions: The postradiation nPSA value is the strongest prognostic indicator of all early PSA-based variables. However, its use as a surrogate endpoint needs to take into account its dependence on pretreatment variables and treatment method. [ABSTRACT FROM AUTHOR]

Purpose: We sought to determine whether short-term neoadjuvant androgen deprivation (STAD) duration influences the optimal time point from which Phoenix fail (time to biochemical failure; TTBF) should be measured. Methods and Materials: In the Trans-Tasman Radiation Oncology Group 96.01 trial, men with locally advanced prostate cancer were randomized to 3 or 6 months STAD before and during prostatic irradiation (XRT) or to XRT alone. The prognostic value of TTBF measured from the end of radiation (ERT) and randomization were compared using Cox models. Results: Between 1996 and 2000, 802 eligible patients were randomized. In 436 men with Phoenix failure, TTBF measured from randomization was a powerful predictor of prostate cancer–specific survival and marginally more accurate than TTBF measured from ERT in Cox models. Insufficient data were available to confirm that TTBF measured from testosterone recovery may also be a suitable option. Conclusions: TTBF measured from randomization (commencement of therapy) performed well in this trial dataset and will be a convenient option if this finding holds in other datasets that include long-term androgen deprivation data. [Copyright &y& Elsevier]

Purpose: We studied prostate-specific antigen (PSA) changes after radiation with or without neoadjuvant androgen deprivation to determine posttreatment PSA scenarios in which false-positive biochemical failures (FPBF) are most likely to occur. Methods and Materials: In the Trans-Tasman Radiation Oncology 96.01 Group trial, patients with T2b, 2c, 3, 4 N0 prostate cancer were randomized to 3 or 6 months goserelin and flutamide (STAD) before and during 66 Gy to the prostate and seminal vesicles (XRT) or to XRT alone. Piecewise longitudinal changes in PSA before relapse were characterized and quantified to determine which might cause FPBF calls. Results: Between 1996 and 2000, 802 eligible patients were randomized. Of these, 492 met the criteria for American Society for Therapeutic Radiology and Oncology (ASTRO) failure and 467 for Phoenix failure. Seventy-seven ASTRO fails and 39 Phoenix fails were deemed false positives (FPs). The majority of FPBFs were associated with the “plateauing” in PSA values that follow posttreatment nadir. FPBFs were particularly common in men treated with STAD, in whom small, consecutive PSA rises before or during this phenomenon triggered 56 FP ASTRO fail calls. In these men, the Phoenix fail criteria triggered only 15 FPBF calls. However, the Phoenix criteria were more vulnerable than ASTRO to short-term isolated PSA rises during plateau, which resulted in 15 Phoenix fail calls but only 3 FP ASTRO fails. Conclusions: The Phoenix definition avoided 50% of FPBF calls that occurred with the ASTRO definition. Failures should be confirmed by further PSA rises before investigation and treatment is considered. [Copyright &y& Elsevier]

Abstract: Background: We sought to determine whether inter-patient variations in pattern of PSA changes after radiation exist and, if so, are they prognostically significant. Methods: In the Trans-Tasman Radiation Oncology Group (TROG) 96.01 randomized controlled trial, patients with T2b,c,3,4 N0 prostate cancer (PC) were randomised to 0, 3 or 6months maximal androgen deprivation prior to 66Gy to the prostate and seminal vesicles (XRT). Patterns of anatomical site of failure were one of the trial endpoints. Serial serum PSA’s were mandated at all follow-up visits. Pattern recognition software was developed to characterize PSA response “signatures” (PRS) after therapy in individual patients. Results: By 2000, 270 eligible patients were randomised to radiation alone. Individual patient PSA values were observed to descend after radiation according to one of two characteristic “signatures”: single exponential (PRS Type 1), non-exponential (PRS Type 2). Compared to PRS Type 1, men with PRS Type 2 (50% of the group) had lower PSA nadir (nPSA) levels (p <.0001), longer doubling times on relapse (p =.006) and significantly lower rates of local (hazard ratio [HR]: 0.47, 95% confidence interval [0.30–0.75], p =.0014) and distant failure (HR: 0.25[0.13–0.46], p <.0001), death due to PC (HR: 0.20[0.10–0.42], p <.0001) and death due to any cause (HR: 0.37 [0.23–0.60], p <.0001). PRS retained its powerful prognostic significance in Cox models that incorporated all key pre-treatment covariates and nPSA. Conclusions: PRS reflect the presence of tumor phenotypes that vary substantially in their clinical behavior and response to XRT. Molecular characterization is now necessary. [Copyright &y& Elsevier]