Adjuvant radiotherapy versus early salvage radiotherapy following radical prostatectomy (TROG 08.03/ANZUP RAVES): a randomised, controlled, phase 3, non-inferiority trial.

BACKGROUND: Adjuvant radiotherapy has been shown to halve the risk of biochemical progression for patients with high-risk disease after radical prostatectomy. Early salvage radiotherapy could result in similar biochemical control with lower treatment toxicity. We aimed to compare biochemical progression between patients given adjuvant radiotherapy and those given salvage radiotherapy. METHODS: We did a phase 3, randomised, controlled, non-inferiority trial across 32 oncology centres in Australia and New Zealand. Eligible patients were aged at least 18 years and had undergone a radical prostatectomy for adenocarcinoma of the prostate with pathological staging showing high-risk features defined as positive surgical margins, extraprostatic extension, or seminal vesicle invasion; had an Eastern Cooperative Oncology Group performance status of 0-1, and had a postoperative prostate-specific antigen (PSA) concentration of 0·10 ng/mL or less. Patients were randomly assigned (1:1) using a minimisation technique via an internet-based, independently generated allocation to either adjuvant radiotherapy within 6 months of radical prostatectomy or early salvage radiotherapy triggered by a PSA of 0·20 ng/mL or more. Allocation sequence was concealed from investigators and patients, but treatment assignment for individual randomisations was not masked. Patients were stratified by radiotherapy centre, preoperative PSA, Gleason score, surgical margin status, and seminal vesicle invasion status. Radiotherapy in both groups was 64 Gy in 32 fractions to the prostate bed without androgen deprivation therapy with real-time review of plan quality on all cases before treatment. The primary endpoint was freedom from biochemical progression. Salvage radiotherapy would be deemed non-inferior to adjuvant radiotherapy if freedom from biochemical progression at 5 years was within 10% of that for adjuvant radiotherapy with a hazard ratio (HR) for salvage radiotherapy versus adjuvant radiotherapy of 1·48. The primary analysis was done on an intention-to-treat basis. This study is registered with ClinicalTrials.gov, NCT00860652. FINDINGS: Between March 27, 2009, and Dec 31, 2015, 333 patients were randomly assigned (166 to adjuvant radiotherapy; 167 to salvage radiotherapy). Median follow-up was 6·1 years (IQR 4·3-7·5). An independent data monitoring committee recommended premature closure of enrolment because of unexpectedly low event rates. 84 (50%) patients in the salvage radiotherapy group had radiotherapy triggered by a PSA of 0·20 ng/mL or more. 5-year freedom from biochemical progression was 86% (95% CI 81-92) in the adjuvant radiotherapy group versus 87% (82-93) in the salvage radiotherapy group (stratified HR 1·12, 95% CI 0·65-1·90; pnon-inferiority=0·15). The grade 2 or worse genitourinary toxicity rate was lower in the salvage radiotherapy group (90 [54%] of 167) than in the adjuvant radiotherapy group (116 [70%] of 166). The grade 2 or worse gastrointestinal toxicity rate was similar between the salvage radiotherapy group (16 [10%]) and the adjuvant radiotherapy group (24 [14%]). INTERPRETATION: Salvage radiotherapy did not meet trial specified criteria for non-inferiority. However, these data support the use of salvage radiotherapy as it results in similar biochemical control to adjuvant radiotherapy, spares around half of men from pelvic radiation, and is associated with significantly lower genitourinary toxicity. FUNDING: New Zealand Health Research Council, Australian National Health Medical Research Council, Cancer Council Victoria, Cancer Council NSW, Auckland Hospital Charitable Trust, Trans-Tasman Radiation Oncology Group Seed Funding, Cancer Research Trust New Zealand, Royal Australian and New Zealand College of Radiologists, Cancer Institute NSW, Prostate Cancer Foundation Australia, and Cancer Australia.

Radiation Dose Escalation or Longer Androgen Suppression to Prevent Distant Progression in Men With Locally Advanced Prostate Cancer: 10-Year Data From the TROG 03.04 RADAR Trial.

PURPOSE: To clarify the relative effects of duration of androgen suppression (AS) and radiation dose escalation (RDE) on distant progression (DP) in men with locally advanced prostate cancer. METHODS AND MATERIALS: Participants with locally advanced prostate cancer in the TROG 03.04 RADAR trial were randomized to 6 or 18 months AS ± 18 months zoledronic acid (Z). The trial incorporated a RDE program by stratification at randomization and dosing options were 66, 70, or 74 Gy external beam radiation therapy (EBRT), or 46 Gy EBRT plus high-dose-rate brachytherapy boost (HDRB). The primary endpoint for this study was distant progression (DP). Secondary endpoints included local progression, bone progression, prostate cancer-specific mortality and all-cause mortality. Effect estimates for AS duration and RDE were derived using Fine and Gray competing risk models adjusting for use of Z, age, tumor stage, Gleason grade group, prostate-specific antigen, and treatment center. Cumulative incidence at 10 years was estimated for each RDE group. RESULTS: A total of 1051 out of 1071 randomized subjects were eligible for inclusion in this analysis. Compared with 6 months AS, 18 months AS significantly reduced DP independently of radiation dose (subhazard ratio 0.70; 95% confidence interval [CI], 0.56-0.87; P = .002). No statistically significant interaction between effect of AS duration and RT dose was observed (Wald test P = .76). In subgroup analyses, DP was significantly reduced by the longer duration of AS in the 70 Gy and HDRB groups but not in the 66 Gy and 74 Gy. Compared with 70 Gy, HDRB significantly reduced DP (subhazard ratio 0.68 [95% CI, 0.57-0.80]; P < .0001) independently of AS duration. At 10 years, adjusted cumulative incidences were 26.1% (95% CI, 18.9%-33.2%), 26.7% (22.9%-30.6%), 24.9% (20.0%-29.8%) and 19.7% (15.5%-23.8%) for DPs in the respective radiation dose groups. CONCLUSIONS: Compared with 6 months AS, 18 months AS reduced DP independently of radiation dose. Men treated with HDRB gained a significant benefit from a longer duration of AS. Evidence of improved oncologic outcomes for HDRB compared with dose-escalated EBRT needs to be confirmed in a randomized trial.

Escalated-dose versus control-dose conformal radiotherapy for prostate cancer: long-term results from the MRC RT01 randomised controlled trial.

BACKGROUND: The aim of this trial was to compare dose-escalated conformal radiotherapy with control-dose conformal radiotherapy in patients with localised prostate cancer. Preliminary findings reported after 5 years of follow-up showed that escalated-dose conformal radiotherapy improved biochemical progression-free survival. Based on the sample size calculation, we planned to analyse overall survival when 190 deaths occurred; this target has now been reached, after a median 10 years of follow-up. METHODS: RT01 was a phase 3, open-label, international, randomised controlled trial enrolling men with histologically confirmed T1b-T3a, N0, M0 prostate cancer with prostate specific antigen of less than 50 ng/mL. Patients were randomly assigned centrally in a 1:1 ratio, using a computer-based minimisation algorithm stratifying by risk of seminal vesicle invasion and centre to either the control group (64 Gy in 32 fractions, the standard dose at the time the trial was designed) or the escalated-dose group (74 Gy in 37 fractions). Neither patients nor investigators were masked to assignment. All patients received neoadjuvant androgen deprivation therapy for 3-6 months before the start of conformal radiotherapy, which continued until the end of conformal radiotherapy. The coprimary outcome measures were biochemical progression-free survival and overall survival. All analyses were done on an intention-to-treat basis. Treatment-related side-effects have been reported previously. This trial is registered, number ISRCTN47772397. FINDINGS: Between Jan 7, 1998, and Dec 20, 2001, 862 men were registered and 843 subsequently randomly assigned: 422 to the escalated-dose group and 421 to the control group. As of Aug 2, 2011, 236 deaths had occurred: 118 in each group. Median follow-up was 10·0 years (IQR 9·1-10·8). Overall survival at 10 years was 71% (95% CI 66-75) in each group (hazard ratio [HR] 0·99, 95% CI 0·77-1·28; p=0·96). Biochemical progression or progressive disease occurred in 391 patients (221 [57%] in the control group and 170 [43%] in the escalated-dose group). At 10 years, biochemical progression-free survival was 43% (95% CI 38-48) in the control group and 55% (50-61) in the escalated-dose group (HR 0·69, 95% CI 0·56-0·84; p=0·0003). INTERPRETATION: At a median follow-up of 10 years, escalated-dose conformal radiotherapy with neoadjuvant androgen deprivation therapy showed an advantage in biochemical progression-free survival, but this advantage did not translate into an improvement in overall survival. These efficacy data for escalated-dose treatment must be weighed against the increase in acute and late toxicities associated with the escalated dose and emphasise the importance of use of appropriate modern radiotherapy methods to reduce side-effects. FUNDING: UK Medical Research Council.

T1-2 anal carcinoma requires elective inguinal radiation treatment--the results of Trans Tasman Radiation Oncology Group study TROG 99.02.

BACKGROUND AND PURPOSE: Elective inguinal irradiation increases morbidity. We describe outcomes of moderate intensity chemoradiation treating anal canal and adjacent pelvic nodes only. MATERIAL AND METHODS: Forty patients with T1-2, N0 anal carcinoma were enrolled between March 1999 and March 2003. Inguinal nodes were NOT electively irradiated. The anal canal and regional pelvic nodes received 36 Gy/20# over 4 weeks, and 2 weeks later the anal canal was boosted with 14.4 Gy/8#. Chemotherapy was 5 fluorouracil 800 mg/m(2)/day on days 1-4 and 36-39, and Mitomycin C 10mg/m(2) on day 1. RESULTS: Median follow-up was 44 months. Complete response was 95%. Four year results were; overall survival 71%, local control 82%, and colostomy-free survival (including salvage) 85%. Inguinal failure occurred in 22.5% but was isolated in only 12.5%. Treatment was well tolerated acutely with no toxic deaths. Severe late toxicity occurred in 7.5%. CONCLUSIONS: This moderate dose 'non inguinal' chemoradiation regimen resulted in modest acute toxicity, minimal long term morbidity and local control in line with other series. However staging failed to identify 12.5% of patients whose isolated inguinal failure might have been prevented by elective irradiation. Without more effective staging, all patients should receive elective inguinal irradiation.

The early toxicity of escalated versus standard dose conformal radiotherapy with neo-adjuvant androgen suppression for patients with localised prostate cancer: results from the MRC RT01 trial (ISRCTN47772397).

BACKGROUND: Five-year disease-free survival rates for localised prostate cancer following standard doses of conventional radical external beam radiotherapy are around 80%. Conformal radiotherapy (CFRT) raises the possibility that radiotherapy doses can be increased and long-term efficacy outcomes improved, with safety an important consideration. METHODS: MRC RT01 is a randomised controlled trial of 862 men with localised prostate cancer comparing Standard CFRT (64Gy/32f) versus Escalated CFRT (74Gy/37f), both administered with neo-adjuvant androgen suppression. Early toxicity was measured using physician-reported instruments (RTOG, LENT/SOM, Royal Marsden Scales) and patient-reported questionnaires (MOS SF-36, UCLA Prostate Cancer Index, FACT-P). RESULTS: Overall early radiotherapy toxicity was similar, apart from increased bladder, bowel and sexual toxicity, in the Escalated Group during a short immediate post-radiotherapy period. Toxicity in both groups had abated by week 12. Using RTOG Acute Toxicity scores, cumulative Grade 2 bladder and bowel toxicity was 38% and 30% for Standard Group and 39% and 33% in Escalated Group, respectively. Urinary frequency (Royal Marsden Scale) improved in both groups from pre-androgen suppression to 6 months post-radiotherapy (p<0.001), but bowel and sexual functioning deteriorated. This pattern was supported by patient-completed assessments. Six months after starting radiotherapy the incidence of RTOG Grade > or = 2 side-effects was low (<1%); but there were six reports of rectal ulceration (6 Escalated Group), six haematuria (5 Escalated Group) and eight urethral stricture (6 Escalated Group). CONCLUSIONS: The two CFRT schedules with neo-adjuvant androgen suppression have broadly similar early toxicity profiles except for the immediate post-RT period. At 6 months and compared to before hormone therapy, bladder symptoms improved, whereas bowel and sexual symptoms worsened. These assessments of early treatment safety will be complemented by further follow-up to document late side-effects and efficacy.

Efficacy and tolerability of concurrent weekly low dose cisplatin during radiation treatment of localised muscle invasive bladder transitional cell carcinoma: a report of two sequential Phase II studies from the Trans Tasman Radiation Oncology Group.

BACKGROUND AND PURPOSE: To determine the feasibility, toxicity, and clinical effectiveness of concurrent weekly cisplatin chemotherapy in conjunction with definitive radiation in the treatment of localised muscle invasive bladder cancer. PATIENTS AND METHODS: In January 1997 the Trans Tasman Radiation Oncology Group embarked on a Phase II study (TROG 97.01) of weekly cisplatin (35 mg/m(2) x 7 doses) plus radiation to a dose of 63 Gy over 7 weeks. Following an interim toxicity analysis, the dose intensity of cisplatin was reduced to 6 cycles and the radiation schedule changed to 64 Gy over 6.5 weeks leading to the second study (TROG 99.06). A total of 113 patients were enrolled. RESULTS: Acute grade 3 urinary toxicity occurred in 23% of the patients. Acute grade 4 pelvic toxicity was not seen. Thirty-eight patients (33%) experienced grade 3 or 4 cisplatin related toxicities with 15 patients (12%) requiring significant dose modification. The reduced dose intensity in Study 99.06 improved tolerability. Incidence of significant late morbidity was low (6%). Seventy-nine patients (70%) achieved complete remission at the 6 month cystoscopic assessment. Local invasive recurrence was seen in 11 of the 79 patients (14%). In 18 patients (16%) isolated superficial TCC/CIS were detected (6 months and beyond). The local control rate was 45% with a functional bladder being retained in 69 of the 113 patients (61%). RFS and DSS at 5 years were 33% and 50%, respectively. CONCLUSION: Our two sequential Phase II studies have shown that concurrent chemoradiation using weekly cisplatin in the management of localised invasive bladder TCC is feasible and reasonably well tolerated. This approach is currently being investigated further in a randomised study.

Estimation of radiation-induced interphase cell death in cultures of human tumor material and in cell lines.

A short-term assay method able to estimate the radiation response of human cancer tissue samples would be of great advantage to the individualization of radiotherapy in cancer patients. However, the effect of radiation on [3H]thymidine incorporation by proliferating cells reflects a composite of cell cycle arrest and induced cell death pathways. Here we consider whether it is feasible to correct for cell cycle effects based on comparison of the effects of radiation and the mitotic inhibitor paclitaxel on [3H]thymidine incorporation. Sixty-two short-term (7-day) cultures of human tumor tissue from 61 patients with melanoma, gynecological cancer, brain cancer, and head and neck cancer, as well as 18 5-day cultures of low passage human tumor cell lines, were irradiated at doses from 2 to 9 Gy, or exposed to paclitaxel (200 nM). [3H]Thymidine incorporation was measured at the end of the incubation. Cell cycle times could be estimated from the paclitaxel data and were 2.7 to 18.6 days for melanomas, 2.5 to >40 days for carcinomas, 3.9 to 39 days for brain tumors, and 1.1 to 3.8 days for cell lines. The effects of radiation on [3H]thymidine incorporation varied widely (0-97% and 0-99% inhibition for 2 and 9 Gy, respectively), and in 23 of the clinical samples, but in none of the cell lines, radiation caused significantly greater inhibition of [3H]thymidine incorporation than paclitaxel (p < 0.05). We argue that that these differences reflect radiation-induced cell loss from G1 phase and/or S phase. Responses of short-term cultures of clinical tumor material to radiation, with appropriate correction for cell cycle effects, might have the potential to provide information on radiation-induced cell death in individual patients.