Meta-Analysis Reveals Optimal Androgen-Deprivation Therapy Duration for Localized Prostate Cancer Treatment
Key Insights
A comprehensive meta-analysis of 10,266 patients from 13 randomized phase III trials found that longer durations of androgen-deprivation therapy with radiotherapy provide nonlinear survival benefits in localized prostate cancer.
The study revealed that 3-month and 9-month androgen-deprivation therapy durations showed significantly poorer overall survival compared to 36-month treatment, while 18-month therapy showed no significant difference.
Optimal therapy durations varied by risk category, with 0, 6, and 12 months recommended for patients with one intermediate-risk factor, multiple intermediate-risk factors, and high-risk disease, respectively.
A large-scale meta-analysis published in JAMA Oncology has provided new insights into optimizing androgen-deprivation therapy duration for men with localized prostate cancer receiving definitive radiotherapy. The study, led by Zaorsky et al, analyzed patient-level data from 13 randomized phase III trials and found that longer durations of androgen-deprivation therapy were associated with nonlinear relative benefits in overall survival.
Study Design and Patient Population
The meta-analysis included 10,266 patients from randomized trials evaluating definitive radiotherapy alone or combined with androgen-deprivation therapy. The patient population had a median age of 70 years (interquartile range 65-74 years), with 7,392 patients (72%) presenting with National Comprehensive Cancer Network (search) (NCCN) high-risk or very high-risk disease. Androgen-deprivation therapy duration ranged from 0 months (radiotherapy alone) to 36 months, with a median follow-up of 11.3 years (interquartile range 9.5-14.5 years).
Survival Outcomes Reveal Duration-Dependent Benefits
The analysis demonstrated significant differences in overall survival based on androgen-deprivation therapy duration. Compared with 36 months of treatment, patients receiving shorter durations showed poorer outcomes: 3 months of therapy resulted in a hazard ratio of 1.75 (95% confidence interval 1.37-2.24), while 9 months showed a hazard ratio of 1.50 (95% confidence interval 1.07-2.10). Notably, no significant difference was observed between 36 and 18 months of treatment (hazard ratio 1.02, 95% confidence interval 0.83-1.26).
The study also revealed that longer durations of androgen-deprivation therapy were associated with nonlinear improvement in relative benefits for risk of distant metastases and prostate cancer-specific mortality. However, reduced estimated benefits were observed beyond androgen-deprivation therapy durations of 9 to 12 months.
Balancing Cancer Control with Treatment-Related Mortality
A critical finding emerged regarding non-cancer mortality risk. The analysis showed a near-linear increase in risk of mortality from causes other than prostate cancer with longer duration of androgen-deprivation therapy. The hazard ratio for 28 versus 0 months was 1.28 (95% confidence interval 1.09-1.50, P = .002). Compared with 36 months of treatment, risk of other-cause mortality was lower with 3 months (hazard ratio 0.60, 95% confidence interval 0.45-0.80) and 6 months (hazard ratio 0.77, 95% confidence interval 0.66-0.89).
Risk-Stratified Treatment Recommendations
The investigators identified optimal androgen-deprivation therapy durations based on 10-year risk of distant metastasis according to NCCN risk categories. For patients with one NCCN intermediate-risk factor, the optimal duration was 0 months. Patients with two or more NCCN intermediate-risk factors showed optimal benefit at 6 months, while those with NCCN high-risk disease benefited most from 12 months of therapy. For patients with NCCN very high-risk disease, the optimal duration remained "undefined," suggesting these patients may require individualized approaches.
Clinical Implications for Personalized Treatment
The study's lead author, Daniel E. Spratt, MD, from the Department of Radiation Oncology at University Hospitals Seidman Cancer (search), Case Western Reserve University, emphasized the clinical significance of these findings. The investigators concluded that "for men with localized prostate cancer treated with definitive radiotherapy and androgen-deprivation therapy, there are relative and absolute benefits from increasing durations of androgen-deprivation therapy that help provide individualized risk estimates."
These results provide clinicians with evidence-based guidance for tailoring androgen-deprivation therapy duration to individual patient risk profiles, potentially optimizing cancer control while minimizing treatment-related morbidity and mortality.