This study aimed to prospectively investigate magnetic resonance (MR)-guided radiotherapy (MRgRT) for post-prostatectomy prostate cancer and report preliminary clinical outcomes.
All included patients underwent salvage or adjuvant adaptive MRgRT on a 1. 5T MR integrated linear accelerator (MR-LINAC). Gastrointestinal and genitourinary toxicities were assessed. The primary endpoint was the progression-free survival (PFS) rate estimated by Kaplan-Meier (KM) survival analysis. A progression event was defined as the first occurrence of biochemical failure, radiological progression, or death. Secondary endpoints were biochemical failure-free survival (bFFS) rate, radiological PFS (rPFS) rate, and ≥G2 adverse events.
Thirty post-prostatectomy patients were enrolled and followed (median follow-up: 32.0 months; 3.0-48.1 months). Three patients had biochemical failure during follow-up. One patient developed pelvic node metastases. All patients were alive. The estimated PFS rates were 96.4% (95% confidence interval [95%CI]: 89.8%-100.0%) at 2 years and 78.8% (95%CI: 61.3%-100%) at 3 years. The estimated bFFS rates were 96.4% (95%CI: 89.8%-100%) /86.6%(95%CI: 73.4%-100%) at 2/3 years, respectively. The corresponding rPFS rates were 100% at 2 years and 92.3% (95%CI: 78.9%-100%) at 3 years, respectively. There was only one acute G2 GI adverse event (1/30, 3.33%) of abdominal pain occurred. Two late G2 events (one rectal bleeding and one urinary frequency) were scored (2/30, 6.67%). No ≥G3 events were observed.
Our findings suggest the feasibility, excellent patient tolerance, and encouraging efficacy of post-prostatectomy MRgRT, extending our knowledge of the clinical outcomes of MRgRT and serving as a benchmark for future investigation.
Asia-Pacific journal of clinical oncology. 2024 Dec 04 [Epub ahead of print]
Darren M C Poon, Jing Yuan, Oi Lei Wong, Bin Yang, Mei Yan Tse, Yan Yee Fung, Sin Ting Chiu, Wai Chi Lin, Kin Yin Cheung, George Chiu, Siu Ki Yu
Comprehensive Oncology Center, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong SAR., Research Department, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong SAR., Medical Physics Department, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong SAR., Department of Radiotherapy, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong SAR.