Does Sequencing of ADT With Radiotherapy Impact Long-Term Outcomes in Localized Prostate Cancer?
Posted: Tuesday, December 8, 2020
Daniel E. Spratt MD, of the University of Michigan Rogel Cancer Center, Ann Arbor, and colleagues, determined the optimal timing of androgen-deprivation therapy (ADT) with radiotherapy in localized prostate cancer. This combined individual patient analysis of two randomized trials was presented during the virtual 2020 American Society for Radiation Oncology (ASTRO) Annual Meeting (Abstract 32).
“We demonstrate for the first time that sequencing of ADT with radiotherapy significantly impacts long-term oncologic outcomes in localized prostate cancer, favoring an adjuvant rather than neoadjuvant-based approach, without increasing late toxicity,” concluded the study authors. “These data have important implications to ongoing and future clinical trial design.”
This phase III trial utilized cases from the Malone et al study (JCO 2019), in which patients were randomly administered concurrent/adjuvant or neoadjuvant/concurrent ADT for 6 months with prostate-alone radiotherapy, and individuals from the RTOG 9413 study, who received similar treatments but over 4 months. To condense, neoadjuvant/concurrent arms were combined into the “neoadjuvant” group, whereas concurrent/adjuvant and adjuvant arms were combined into the “adjuvant” group. Progression-free survival, overall survival, prostate cancer–specific mortality, biochemical failure, and cumulative incidence of distant metastasis were assessed, along with late grade 3 or higher genitourinary and gastrointestinal toxicities.
A total of 1,065 patients were included, with 531 in the neoadjuvant arm and 534 in the adjuvant arm. At the median follow-up of 14.9 years, progression-free survival, overall survival, prostate cancer–specific mortality, biochemical failure, and cumulative incidence of distant metastasis for adjuvant and neoadjuvant arms were 36% and 29%, 39% and 34%, 15% and 20%, 33% and 43%, and 12% and 18%, respectively. No significant increase in late grade 3 or higher genitourinary or gastrointestinal toxicities was reported.
Disclosure: For full disclosures of the study authors, visit redjournal.org.
