Every-other-day or once-a-week: Long-term efficacy outcomes of the multicenter randomised PATRIOT prostate SBRT trial.

• DOI: 10.1200/jco.2024.42.4_suppl.325
• Publication Date: 2024-01-29T21:06:41Z
• Authors: Wee Loon Ong; Harvey Charles Quon; Aldrich Ong; Patrick Cheung; William Chu; Hans T. Chung; Danny Vesprini; Amit Chowdhury; Dilip Panjwani; Yasir Alayed; Geordi Pang; Renee Korol; Melanie Davidson; Ananth Ravi; Boyd McCurdy; Liying Zhang; Meghan Kulasingha...; Alexandre Mamedov; Andrea Deabreu; Andrew Loblaw
• Keywords: 03 medical and health sciences; 0302 clinical medicine

325 Background: We aim to report the long-term efficacy outcomes of PATRIOT trial, a multicenter phase 2 randomised trial every-other-day (EOD) versus once-a-week (QW) schedule for stereotactic body radiotherapy (SBRT) prostate cancer (NCT01423474). Methods: Between January 2012 and November 2013, 152 men with low intermediate risk were SBRT 40Gy in 5 fractions, delivered EOD (n=75) or QW (n=77). The oncological evaluated biochemical failure (BF) (based on Phoenix criteria), metastases free survival (MFS), specific (PCSS) overall (OS). Time-to-event was estimated from start date event interest last follow-up. cumulative incidence BF using Nelson Aalen estimates, while MFS, PCSS OS Kaplan Meier method. Results: median follow-up cohort 91 months (IQR: 61-116 months). Five arm eight developed BF. 8-year 5.5% (SE=0.03) 9.6% (SE=0.04) (P=0.3). None metastases, three did. MFS 100% 95.9% (95%CI=91.4-100%) (P=0.08). Thirteen had died at follow-up, which two death. 97.2% (95%CI=93.5-100%) (P=0.3), 96.0% (95%CI=91.7-100%) 85.4% (95%CI=76.4-95.5%) Conclusions: There are no statistically significant differences between five-fraction trial. However, powered acute toxicity differences, not OS. Either could be safely depending patients’ preference, logistic reasons. plan combine these data Swiss vs (NCT01764646) improve power detect important outcomes. Clinical information: NCT01423474 .