Time to Benefit of Androgen Deprivation Therapy in Patients With Localized Prostate Cancer Undergoing Radiotherapy

Area of Science:

• Oncology
• Radiation Oncology
• Medical Statistics

Background:

• Radiotherapy combined with androgen deprivation therapy (ADT) is a standard treatment for localized prostate cancer.
• The precise time to achieve significant therapeutic benefits from ADT in conjunction with radiotherapy remains incompletely understood.

Purpose of the Study:

• This study aimed to quantify the time to benefit (TTB) for patients with localized prostate cancer receiving radiotherapy plus ADT.

Main Methods:

• A systematic literature review of randomized clinical trials was conducted across PubMed, Scopus, Embase, and Cochrane databases.
• Trials compared definitive radiotherapy with or without ADT for localized prostate cancer, with all-cause mortality as the primary endpoint.
• Individual patient survival data were reconstructed to calculate TTB using Weibull survival curves, the frequentist method, and the delta method.

Main Results:

• Eight trials involving 6,839 participants, predominantly with intermediate- or high-risk prostate cancer, were analyzed.
• For every 100 patients receiving ADT with radiotherapy, the time to prevent one case of all-cause mortality ranged from 7.46 to 30.90 months, depending on the benefit threshold.
• Preventing one case of prostate cancer-specific mortality, local progression, distant metastasis, or biochemical failure per 100 patients required 40.58, 10.92, 11.36, and 7.80 months, respectively.

Conclusions:

• The addition of ADT to radiotherapy yields rapid clinical benefits for patients diagnosed with intermediate- and high-risk localized prostate cancer.
• This combined treatment strategy is particularly beneficial for patients with an anticipated lifespan exceeding 30 months.