Long-Term Results With Hormonal Therapy Plus Radiotherapy in Prostate Cancer
Posted: Monday, November 12, 2018
Among the most important advances in the management of men with intermediate-risk to high-risk localized prostate cancer is the recognition of the important role of hormonal therapy combined with external-beam radiotherapy. To provide insight into this treatment approach, Mack Roach III, MD, FACR, of the University of California San Francisco, and colleagues conducted a phase III study that showed improvement in progression-free survival with neoadjuvant hormonal therapy plus whole-pelvic radiotherapy (WPRT).
The study (NRG/RTOG 0924), with recent updated data published in The Lancet Oncology, involved 1,322 patients who were enrolled from 53 institutions and randomly assigned to 4 treatment groups: neoadjuvant hormonal therapy plus WPRT, neoadjuvant hormonal therapy plus prostate-only radiotherapy, WPRT plus adjuvant hormonal therapy, and prostate-only radiotherapy plus adjuvant hormonal therapy.
Progression-free survival across all timepoints differed significantly among the four treatment groups. The 10-year estimates of progression-free survival 28.4% in the neoadjuvant hormonal therapy plus WPRT group, 23.5% in the neoadjuvant hormonal therapy plus prostate-only radiotherapy group, 19.4% in the WPRT plus adjuvant hormonal therapy group, and 30.2% in the prostate-only radiotherapy plus adjuvant hormonal therapy group. The researchers noted that neoadjuvant hormonal therapy plus WPRT also improved biochemical failure compared with neoadjuvant hormonal therapy plus prostate-only radiotherapy, albeit with an increased risk of grade 3 or worse gastrointestinal toxicity with the use of conventionally delivered, external-beam radiotherapy.
Accrual of all data from this study is expected to be completed by late summer of 2019. The investigators concluded: “We are hopeful that the final results of this study will provide more evidence about whether or not prophylactic WPRT is beneficial to men given definitive radiotherapy and [androgen-deprivation therapy] for unfavorable intermediate-risk or favorable high-risk, clinically localized prostate cancer.”