Poon Darren Mc, Yuan Jing, Wong Oi Lei, Yang Bin, Chiu Sin Ting, Cheung Kin Yin, Chiu George, Yu Siu Ki
Comprehensive Oncology Centre, Hong Kong Sanatorium & Hospital, Hong Kong, Hong Kong SAR, China.
Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, Hong Kong SAR, China.
Front Oncol. 2025 Jul 3;15:1607610. doi: 10.3389/fonc.2025.1607610. eCollection 2025.
To prospectively investigate the feasibility, toxicity, and preliminary clinical outcomes of magnetic resonance (MR)-guided stereotactic total ablative radiotherapy (MRgSTAR) for simultaneous treatment of the prostate and pelvic bone metastases in patients with synchronous oligometastatic prostate cancer (OMPC).
This study included patients with histologically confirmed synchronous OMPC, defined as ≤ 5 lymph node or pelvic bone metastases identified via prostate-specific membrane antigen positron emission tomography (PSMA-PET). Real-time adaptive MRgSTAR was delivered using a 1.5T MR-integrated linear accelerator (MR-LINAC) in five fractions, administered twice weekly, targeting the prostate (33.5-40 Gy) and nodal/bone metastases (36.5-40 Gy) simultaneously. Androgen-deprivation therapy (ADT) was initiated prior to MRgSTAR, with the addition of androgen receptor pathway inhibitor (ARPI) at the physician's discretion. Adverse events (AEs) were assessed using the Common Terminology Criteria for AEs v5.0, and tumor response was evaluated per the Response Evaluation Criteria in Solid Tumors v1.1. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method, with log-rank tests used to explore clinical factors associated with survival outcomes.
Forty-three patients underwent MRgSTAR, with a median follow-up of 36.5 months (range: 15.4-57.6 months). ADT combined with ARPI therapy was administered in 22 patients (52%). All patients completed the five-fraction regimen. Biochemical progression occurred in three patients, of whom two had out-of-field metastases and one had local progression as per follow-up PSMA-PET. The estimated 3-year OS and PFS rates were 100% and 95.2% (95% confidence interval: 89.0%-100%), respectively. No clinical factors, including ARPI use, significantly correlated with survival outcomes. No radiotherapy-related AEs of grade ≥ 3 were observed.
MRgSTAR demonstrates promising early survival outcomes and a favorable toxicity profile in synchronous OMPC, warranting further investigation to confirm its therapeutic role.
前瞻性研究磁共振（MR）引导下立体定向全消融放疗（MRgSTAR）同步治疗寡转移前列腺癌（OMPC）患者的前列腺和盆腔骨转移的可行性、毒性及初步临床疗效。
本研究纳入经组织学确诊的同步OMPC患者，定义为通过前列腺特异性膜抗原正电子发射断层扫描（PSMA-PET）确定的≤5个淋巴结或盆腔骨转移。使用1.5T MR集成直线加速器（MR-LINAC）进行实时自适应MRgSTAR，分5次给予，每周2次，同时靶向前列腺（33.5-40 Gy）和淋巴结/骨转移灶（36.5-40 Gy）。在MRgSTAR之前开始雄激素剥夺治疗（ADT），并根据医生的判断添加雄激素受体途径抑制剂（ARPI）。使用不良事件通用术语标准v5.0评估不良事件（AE），并根据实体瘤疗效评价标准v1.1评估肿瘤反应。采用Kaplan-Meier方法估计无进展生存期（PFS）和总生存期（OS），使用对数秩检验探索与生存结果相关的临床因素。
43例患者接受了MRgSTAR治疗，中位随访时间为36.5个月（范围：15.4-57.6个月）。22例患者（52%）接受了ADT联合ARPI治疗。所有患者均完成了5次分割方案。3例患者发生生化进展，根据随访PSMA-PET，其中2例有野外转移，1例有局部进展。估计3年OS率和PFS率分别为100%和95.2%（95%置信区间：89.0%-100%）。没有临床因素，包括ARPI的使用，与生存结果显著相关。未观察到≥3级的放疗相关AE。
MRgSTAR在同步OMPC中显示出有前景的早期生存结果和良好的毒性特征，值得进一步研究以确认其治疗作用。
