As reported in The Lancet Oncology by Carrie et al, the 112-month follow-up of the French phase III GETUG-AFU 16 trial has confirmed the initial 5-year report of the trial, which reported improved progression-free survival with the addition of short-term androgen-deprivation therapy (ADT) to radiotherapy in men with rising prostate-specific antigen after radical prostatectomy for prostate cancer. The analysis at 5 years showed no overall survival benefit.
The open-label trial included 743 patients from 43 Unicancer Genitourinary Group (GETUG) sites who had received no previous androgen suppression or pelvic radiotherapy and had prostate-specific antigen (PSA) levels increasing from 0.1 ng/mL to between 0.2 ng/mL and 2.0 ng/mL after radical prostatectomy without evidence of clinical disease. Patients were randomly assigned between October 2006 and March 2010 to receive goserelin plus radiotherapy (n = 369) or radiotherapy alone (n = 374). Patients had stage pT2, T3, and T4a (bladder neck involvement only) and pN0/pNx disease. Goserelin was given via 10.8 mg subcutaneous injection on the first day of irradiation and 3 months later. Radiotherapy consisted of 3D conformal radiotherapy or intensity-modulated radiotherapy of 66 Gy in 33 fractions given 5 days a week for 7 weeks.
The primary endpoint was biochemical or clinical progression-free survival in the intention-to-treat population.
In the current post hoc analysis, median follow-up was 112 months at data cutoff in March 2019.
The 120-month rate of progression-free survival was 64% in the radiotherapy plus goserelin group vs 49% in the radiotherapy group (hazard ratio [HR] = 0.54, P < .0001). Progression-free survival at 120 months was 74% vs 61% (HR = 0.47, P = .0041) for patients in the low-risk subgroup (29%–31% of patients) and 60% vs 43% (HR = 0.56, P < .0001) for patients in the high-risk subgroup (69%–71% of patients).
Metastasis-free survival at 120 months was 75% vs 69% (HR = 0.73, P = .0339). Overall survival at 120 months was 86% vs 85% (HR = 0.93, P = .73). Mortality due to cancer occurred in 5% vs 3% of patients. Diagnosis of a second cancer occurred in 3% vs 2% of patients.
The investigators concluded, “The 120-month progression-free survival confirmed the results from the primary analysis. Salvage radiotherapy combined with short-term androgen suppression significantly reduced risk of biochemical or clinical progression and death compared with salvage radiotherapy alone. The results of the GETUG-AFU 16 trial confirm the efficacy of androgen suppression plus radiotherapy as salvage treatment in patients with increasing PSA concentration after radical prostatectomy for prostate cancer.”
Christian Carrie, MD, of the Radiotherapy Department, Centre Léon Bérard, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funded by AstraZeneca, The French Health ministry, La Ligue Contre le Cancer, and La Ligue de Haute-Savoie. For full disclosures of the study authors, visit thelancet.com.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.