Previous evidence supports androgen deprivation therapy (ADT) with primary radiotherapy as initial treatment for intermediate-risk and high-risk localised prostate cancer. However, the use and optimal duration of ADT with postoperative radiotherapy after radical prostatectomy remains uncertain.
RADICALS-HD was a randomised controlled trial of ADT duration within the RADICALS protocol. Here, we report on the comparison of short-course versus long-course ADT. Key eligibility criteria were indication for radiotherapy after previous radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to add 6 months of ADT (short-course ADT) or 24 months of ADT (long-course ADT) to radiotherapy, using subcutaneous gonadotrophin-releasing hormone analogue (monthly in the short-course ADT group and 3-monthly in the long-course ADT group), daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as metastasis arising from prostate cancer or death from any cause. The comparison had more than 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 75% to 81% (hazard ratio [HR] 0·72). Standard time-to-event analyses were used. Analyses followed intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047.
Between Jan 30, 2008, and July 7, 2015, 1523 patients (median age 65 years, IQR 60-69) were randomly assigned to receive short-course ADT (n=761) or long-course ADT (n=762) in addition to postoperative radiotherapy at 138 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 8·9 years (7·0-10·0), 313 metastasis-free survival events were reported overall (174 in the short-course ADT group and 139 in the long-course ADT group; HR 0·773 [95% CI 0·612-0·975]; p=0·029). 10-year metastasis-free survival was 71·9% (95% CI 67·6-75·7) in the short-course ADT group and 78·1% (74·2-81·5) in the long-course ADT group. Toxicity of grade 3 or higher was reported for 105 (14%) of 753 participants in the short-course ADT group and 142 (19%) of 757 participants in the long-course ADT group (p=0·025), with no treatment-related deaths.
Compared with adding 6 months of ADT, adding 24 months of ADT improved metastasis-free survival in people receiving postoperative radiotherapy. For individuals who can accept the additional duration of adverse effects, long-course ADT should be offered with postoperative radiotherapy.
Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society.
Lancet (London, England). 2024 May 16 [Epub ahead of print]
Chris C Parker, Howard Kynaston, Adrian D Cook, Noel W Clarke, Charles N Catton, William R Cross, Peter M Petersen, Rajendra A Persad, Cheryl A Pugh, Fred Saad, John Logue, Heather Payne, Lorna C Bower, Chris Brawley, Mary Rauchenberger, Maroie Barkati, David M Bottomley, Klaus Brasso, Hans T Chung, Peter W M Chung, Ruth Conroy, Alison Falconer, Vicky Ford, Chee L Goh, Catherine M Heath, Nicholas D James, Charmaine Kim-Sing, Ravi Kodavatiganti, Shawn C Malone, Stephen L Morris, Abdenour Nabid, Aldrich D Ong, Rakesh Raman, Sree Rodda, Paula Wells, Jane Worlding, Wendy R Parulekar, Mahesh K B Parmar, Matthew R Sydes, RADICALS investigators
The Royal Marsden NHS Foundation Trust, London, UK; The Institute of Cancer Research, London, UK., Division of Cancer and Genetics, Cardiff University Medical School, Cardiff, UK., MRC Clinical Trials Unit at UCL, Institute of Clinical Trials and Methodology, University College London, London, UK., Department of Urology, The Christie NHS Foundation Trust, Manchester, UK; Division of Cancer Sciences, University of Manchester, Manchester, UK; Department of Urology, Salford Royal Hospital, Salford, UK., Princess Margaret Cancer Centre, Toronto, ON, Canada., Department of Urology, St James's University Hospital, Leeds, UK., Department of Oncology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark., Department of Urology, Bristol Urological Institute, Bristol, UK., Department of Urology, Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada., Department of Urology, The Christie NHS Foundation Trust, Manchester, UK., The Prostate Centre, London, UK., The Royal Marsden NHS Foundation Trust, London, UK; The Institute of Cancer Research, London, UK; Guy's and St Thomas' NHS Foundation Trust, London, UK., Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montréal, QC, Canada., Department of Clinical Oncology, St James's University Hospital, Leeds, UK., Department of Urology, Copenhagen Prostate Cancer Center, Rigshospitalet, Copenhagen, Denmark., Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, Toronto, ON, Canada; Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada., Princess Margaret Cancer Centre, Toronto, ON, Canada; Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada., Department of Clinical Oncology, The Christie NHS Foundation Trust, Manchester, UK., Radiotherapy Department, Charing Cross Hospital, London, UK., Royal Devon and Exeter University NHS Foundation Trust, Exeter, UK., Royal Surrey County Hospital, Guildford, UK., Department of Clinical Oncology, University Hospital Southampton NHS Foundation Trust, Southampton, UK., Department of Radiation Oncology, BC Cancer-Vancouver, Vancouver, BC, Canada., Glan Clwyd Hospital, Betsi Cadwaladr University Health Board, Bangor, UK., The Ottawa Hospital, University of Ottawa, Ottawa, ON, Canada., Guy's and St Thomas' NHS Foundation Trust, London, UK., Service de Radio-Oncologie, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada., Max Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada., Kent Oncology Centre, Kent and Canterbury Hospital, Canterbury, UK., Bradford Teaching Hospitals, Bradford, UK., Barts Cancer Centre, St Bartholomew's Hospital, London, UK., University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK., Canadian Cancer Trials Group, Queen's University, Kingston, ON, Canada., MRC Clinical Trials Unit at UCL, Institute of Clinical Trials and Methodology, University College London, London, UK. Electronic address: .