Allison Steigler

Influence of Androgen Suppression Therapy for Prostate Cancer on the Frequency and Timing of Fatal Myocardial Infarctions

PURPOSE We evaluated whether the timing of fatal myocardial infarction (MI) was influenced by the administration of androgen suppression therapy (AST). PATIENTS AND METHODS The study cohort comprised 1,372 men who were enrolled onto three randomized trials between February 1995 and June 2001. In the three trials, the men were randomly assigned to receive radiation therapy with 0 versus 3 versus 6, 3 versus 8, or 0 versus 6 months of AST. Fine and Grays regression was used to determine the clinical factors associated with the time to fatal MI, and estimates of time to fatal MI were calculated using a cumulative incidence method. When comparing the cumulative incidence estimates using Grays k-sample P values, increased weight was ascribed to the earlier data because recovery of testosterone is expected for most men within 2 years after short-course AST. RESULTS Men age 65 years or older who received 6 months of AST experienced shorter times to fatal MIs compared with men in this age group who did not receive AST (P = .017) and men younger than 65 years (P = .016). No significant difference (P = .97) was observed in the time to fatal MIs in men age 65 years or older who received 6 to 8 months of AST compared with 3 months of AST. CONCLUSION The use of AST is associated with earlier onset of fatal MIs in men age 65 years or older who are treated for 6 months compared with men who are not treated with AST.

Short-term neoadjuvant androgen deprivation and radiotherapy for locally advanced prostate cancer: 10-year data from the TROG 96.01 randomised trial

BACKGROUND The TROG 96.01 trial assessed whether 3-month and 6-month short-term neoadjuvant androgen deprivation therapy (NADT) decreases clinical progression and mortality after radiotherapy for locally advanced prostate cancer. Here we report the 10-year results. METHODS Between June, 1996, and February, 2000, 818 men with T2b, T2c, T3, and T4 N0 M0 prostate cancers were randomly assigned to receive radiotherapy alone, 3 months of NADT plus radiotherapy, or 6 months of NADT plus radiotherapy. The radiotherapy dose for all groups was 66 Gy, delivered to the prostate and seminal vesicles (excluding pelvic nodes) in 33 fractions of 2 Gy per day (excluding weekends) over 6·5-7·0 weeks. NADT consisted of 3·6 mg goserelin given subcutaneously every month and 250 mg flutamide given orally three times a day. NADT began 2 months before radiotherapy for the 3-month NADT group and 5 months before radiotherapy for the 6-month NADT group. Primary endpoints were prostate-cancer-specific mortality and all-cause mortality. Treatment allocation was open label and randomisation was done with a minimisation technique according to age, clinical stage, tumour grade, and initial prostate-specific antigen concentration (PSA). Analysis was by intention-to-treat. The trial has been closed to follow-up and all main endpoint analyses are completed. The trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12607000237482. FINDINGS 802 men were eligible for analysis (270 in the radiotherapy alone group, 265 in the 3-month NADT group, and 267 in the 6-month NADT group) after a median follow-up of 10·6 years (IQR 6·9-11·6). Compared with radiotherapy alone, 3 months of NADT decreased the cumulative incidence of PSA progression (adjusted hazard ratio 0·72, 95% CI 0·57-0·90; p=0·003) and local progression (0·49, 0·33-0·73; p=0·0005), and improved event-free survival (0·63, 0·52-0·77; p<0·0001). 6 months of NADT further reduced PSA progression (0·57, 0·46-0·72; p<0·0001) and local progression (0·45, 0·30-0·66; p=0·0001), and led to a greater improvement in event-free survival (0·51, 0·42-0·61, p<0·0001), compared with radiotherapy alone. 3-month NADT had no effect on distant progression (0·89, 0·60-1·31; p=0·550), prostate cancer-specific mortality (0·86, 0·60-1·23; p=0·398), or all-cause mortality (0·84, 0·65-1·08; p=0·180), compared with radiotherapy alone. By contrast, 6-month NADT decreased distant progression (0·49, 0·31-0·76; p=0·001), prostate cancer-specific mortality (0·49, 0·32-0·74; p=0·0008), and all-cause mortality (0·63, 0·48-0·83; p=0·0008), compared with radiotherapy alone. Treatment-related morbidity was not increased with NADT within the first 5 years after randomisation. INTERPRETATION 6 months of neoadjuvant androgen deprivation combined radiotherapy is an effective treatment option for locally advanced prostate cancer, particularly in men without nodal metastases or pre-existing metabolic comorbidities that could be exacerbated by prolonged androgen deprivation. FUNDING Australian Government National Health and Medical Research Council, Hunter Medical Research Institute, AstraZeneca, and Schering-Plough.

Time to biochemical failure and prostate-specific antigen doubling time as surrogates for prostate cancer-specific mortality : evidence from the TROG 96.01 randomised controlled trial

BACKGROUND Surrogate endpoints for prostate cancer-specific mortality after curative primary treatment are not well established. We sought to assess time to biochemical failure (TTBF) and prostate-specific antigen doubling time (PSADT) after failure of curative treatment as candidates for this endpoint. METHODS PSA and survival data from the Trans-Tasman Radiation Oncology Group (TROG) 96.01 trial were used to assess surrogate candidates. Between June 28, 1996, and Feb 16, 2000, 802 eligible men with locally advanced prostate cancer were randomly allocated to prostatic irradiation alone, or to 3 or 6 months of maximum short-term androgen deprivation (STAD) before and during radiation. Successful surrogates were required to satisfy the Prentice criteria and to predict the trial finding. The TROG 96.01 trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12607000237482. FINDINGS 6 months of STAD was shown to significantly decrease prostate cancer-specific mortality compared with radiation alone, but 3 months of STAD did not result in a decrease. Relative to radiation alone, the hazard ratio of prostate cancer-specific mortality from randomisation was 0.95 (95% CI 0.63-1.41; p=0.79) in the 3-month STAD treatment arm and 0.56 (0.36-0.88; p=0.01) in the 6-month arm. PSADT predicted the trial finding and satisfied all four Prentice criteria at the cutpoints of less than 12 months and less than 15 months, with proportion of treatment effect ratios between 0.36 and 0.56. Time to biochemical failure was better than PSADT at predicting the trial finding and satisfying all four Prentice criteria at cutpoints of less than 1.5, less than 2, and less than 2.5 years, with proportion of treatment effect ratios between 0.45 and 0.64. INTERPRETATION This study provides proof of principle that TTBF and PSADT can be useful as surrogate endpoints for prostate cancer-specific mortality and offer potential to substantially reduce follow up in clinical trials. These endpoints now require assessment in multi-trial meta-analyses before use in clinical trials.

Short-term androgen suppression and radiotherapy versus intermediate-term androgen suppression and radiotherapy, with or without zoledronic acid, in men with locally advanced prostate cancer (TROG 03.04 RADAR): an open-label, randomised, phase 3 factorial trial.

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% (13·0-22·1) in the STAS plus zoledronic acid group, 14·2% (10·3-18·7) in the ITAS group, and 11·1% (7·6-15·2) in the ITAS plus zoledronic acid group; no differences were recorded between groups. Cumulative incidence of secondary therapeutic intervention was 25·6% (20·5-30·9), 28·9% (23·5-34·5), 20·7% (16·1-25·9), and 15·3% (11·3-20·0), respectively. Compared with STAS, ITAS plus zoledronic acid reduced the need for secondary therapeutic intervention (SHR 0·67, 95% CI 0·48-0·95; p=0·024); no differences were noted with the other two groups. An interaction between trial factors was recorded for Gleason score; therefore, we did pairwise comparisons between all groups. Post-hoc analyses suggested that the reductions in PSA progression and decreased need for secondary therapeutic intervention with ITAS plus zoledronic acid were restricted to tumours with a Gleason score of 8-10, and that ITAS was better than STAS in tumours with a Gleason score of 7 or lower. Long-term morbidity and quality-of-life scores were not affected adversely by 18 months of androgen suppression or zoledronic acid. INTERPRETATION Compared with STAS, ITAS plus zoledronic acid was more effective for treatment of prostate cancers with a Gleason score of 8-10, and ITAS alone was effective for tumours with a Gleason score of 7 or lower. Nevertheless, these findings are based on secondary endpoint data and post-hoc analyses and must be regarded cautiously. Long- term follow-up is necessary, as is external validation of the interaction between zoledronic acid and Gleason score. STAS plus zoledronic acid can be ruled out as a potential therapeutic option. 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), Calvary Health Care (Calvary Mater Newcastle Radiation Oncology Fund), Hunter Medical Research Institute, Maitland Cancer Appeal, Cancer Standards Institute New Zealand.

Surrogate endpoints for prostate cancer-specific mortality after radiotherapy and androgen suppression therapy in men with localised or locally advanced prostate cancer: an analysis of two randomised trials

BACKGROUND Androgen suppression therapy and radiotherapy are used to treat locally advanced prostate cancer. 3 years of androgen suppression confers a small survival benefit compared with 6 months of therapy in this setting, but is associated with more toxic effects. Early identification of men in whom radiotherapy and 6 months of androgen suppression is insufficient for cure is important. Thus, we assessed whether prostate-specific antigen (PSA) values can act as an early surrogate for prostate cancer-specific mortality (PCSM). METHODS We systematically reviewed randomised controlled trials that showed improved overall and prostate cancer-specific survival with radiotherapy and 6 months of androgen suppression compared with radiotherapy alone and measured lowest PSA concentrations (PSA nadir) and those immediately after treatment (PSA end). We assessed a cohort of 734 men with localised or locally advanced prostate cancer from two eligible trials in the USA and Australasia that randomly allocated participants between Feb 2, 1996, and Dec 27, 2001. We used Prentice criteria to assess whether reported PSA nadir or PSA end concentrations of more than 0·5 ng/mL were surrogates for PCSM. FINDINGS Men treated with radiotherapy and 6 months of androgen suppression in both trials were significantly less likely to have PSA end and PSA nadir values of more than 0·5 ng/mL than were those treated with radiotherapy alone (p<0·0001). Presence of candidate surrogates (ie, PSA end and PSA nadir values >0·5 ng/mL) alone and when assessed in conjunction with the randomised treatment group increased risk of PCSM in the US trial (PSA nadir p=0·0016; PSA end p=0·017) and Australasian trial (PSA nadir p<0·0001; PSA end p=0·0012). In both trials, the randomised treatment group was no longer associated with PCSM (p ≥ 0·20) when the candidate surrogates were included in the model. Therefore, both PSA metrics satisfied Prentice criteria for surrogacy. INTERPRETATION After radiotherapy and 6 months of androgen suppression, men with PSA end values exceeding 0·5 ng/mL should be considered for long-term androgen suppression and those with localised or locally advanced prostate cancer with PSA nadir values exceeding 0·5 ng/mL should be considered for inclusion in randomised trials investigating the use of drugs that have extended survival in castration-resistant metastatic prostate cancer. FUNDING None.

Short- vs Long-Term Androgen Suppression Plus External Beam Radiation Therapy and Survival in Men of Advanced Age With Node-Negative High-Risk Adenocarcinoma of the Prostate

The study evaluated whether the use of 3 years as compared with 6 months of androgen suppression therapy (AST) combined with external beam radiation therapy (RT) in the treatment of high‐risk prostate cancer was associated with prolonged survival in advanced age men.

A Comparison of the Prognostic Value of Early PSA Test-Based Variables Following External Beam Radiotherapy, With or Without Preceding Androgen Deprivation: Analysis of Data From the TROG 96.01 Randomized Trial

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.

Radiation dose escalation or longer androgen suppression for locally advanced prostate cancer? Data from the TROG 03.04 RADAR trial

BACKGROUND The relative effects of radiation dose escalation (RDE) and androgen suppression (AS) duration on local prostatic progression (LP) remain unclear. METHODS We addressed this in the TROG 03.04 RADAR trial by incorporating a RDE programme by stratification at randomisation. Men were allocated 6 or 18 months AS±18 months zoledronate (Z). The main endpoint was a composite of clinically diagnosed LP or PSA progression with a PSA doubling time ⩾6 months. Fine and Gray competing risk modelling with adjustment for site clustering produced cumulative incidence estimates at 6.5 years for each RDE group. RESULTS Composite LP declined coherently in the 66, 70 and 74 Gy external beam dosing groups and was lowest in the high dose rate brachytherapy boost (HDRB) group. At 6.5 years, adjusted cumulative incidences were 22%, 15%, 13% and 7% respectively. Compared to 6 months AS, 18 months AS also significantly reduced LP (p<0.001). Post-radiation urethral strictures were documented in 45 subjects and increased incrementally in the dosing groups. Crude incidences were 0.8%, 0.9%, 3.8% and 12.7% respectively. CONCLUSION RDE and increasing AS independently reduce LP and increase urethral strictures. The risks and benefits to the individual must be balanced when selecting radiation dose and AS duration.

Why Are Pretreatment Prostate-Specific Antigen Levels and Biochemical Recurrence Poor Predictors of Prostate Cancer Survival?

The value of pretreatment (initial) prostate‐specific antigen (iPSA) and biochemical recurrence (BR) as prognostic factors for survival remains unclear. The authors sought to determine why using randomized trial data with 7‐year minimum follow‐up.

Validation of International Society of Urological Pathology (ISUP) grading for prostatic adenocarcinoma in thin core biopsies using TROG 03.04 ‘RADAR’ trial clinical data

Summary In 2014 a consensus conference convened by the International Society of Urological Pathology (ISUP) adopted amendments to the criteria for Gleason grading and scoring (GS) for prostatic adenocarcinoma. The meeting defined a modified grading system based on 5 grading categories (grade 1, GS 3+3; grade 2, GS 3+4; grade 3, GS 4+3; grade 4, GS 8; grade 5, GS 9–10). In this study we have evaluated the prognostic significance of ISUP grading in 496 patients enrolled in the TROG 03.04 RADAR Trial. There were 19 grade 1, 118 grade 2, 193 grade 3, 88 grade 4 and 79 grade 5 tumours in the series, with follow-up for a minimum of 6.5 years. On follow-up 76 patients experienced distant progression of disease, 171 prostate specific antigen (PSA) progression and 39 prostate cancer deaths. In contrast to the 2005 modified Gleason system (MGS), the hazards of the distant and PSA progression endpoints, relative to grade 2, were significantly greater for grades 3, 4 and 5 of the 2014 ISUP grading scheme. Comparison of predictive ability utilising Harrells concordance index, showed 2014 ISUP grading to significantly out-perform 2005 MGS grading for each of the three clinical endpoints.