没有就原发性外照射治疗之后前列腺癌复发的最佳局部治疗方法达成共识。立体定向体放疗（SBRT）的前瞻性数据非常匮乏。为了确定SBRT拯救最佳剂量方案，本文介绍了GETUG-AFU 31多中心开放标签研究的第一阶段结果。主要纳入标准是：病理证实的生化复发、复发时临床分期为T1-T2、多参数磁共振成像数据、在SBRT拯救治疗前的前列腺特异性抗原（PSA）水平≤10 ng/ml、PSA倍增时间>10个月和国际前列腺症状评分≤12。采用定位SBRT共送出5或6个6 Gy的剂量分数。剂量限制性毒性（DLT）的定义是在治疗开始后的前18周内发生的Ⅲ级或以上的胃肠或泌尿系统毒性，或任何Ⅳ级毒性（根据全国癌症研究所不良事件通用术语第4.03版）。时间加事件持续再评估方法用于选择剂量方案。总共治疗了21例患者（年龄中位数[四分位距]为：76.8岁[72.2-80.8]），其中12例接受了6×6剂量级别。没有观察到DLT。急性2级泌尿系统毒性发生率为19%。经过12.3个月的中位数随访，晚期2级泌尿系统毒性的累积发生率估计为41.2%（95%可信区间：18.1-63.1%）。未报告2级以上泌尿系统毒性和任何3级以上的胃肠道毒性。所有接受治疗的患者在最后的随访中均生存和无复发。我们为拯救SBRT的第二阶段研究选择了6×6 Gy的剂量方案。由于随访时间较短，所以毒性水平似乎是可接受的。对于接受前列腺癌放疗后局部复发患者的最佳局部治疗方法仍没有共识。前瞻性数据非常匮乏。我们的早期研究使我们建议采用高精度放疗的6×6 Gy共分5或6次治疗剂量供进一步研究使用。版权所有©2023年欧洲泌尿科学会。由Elsevier B.V.出版。保留所有权利。

There is no consensus on the best local salvage treatment for prostate cancer recurrence after primary external beam radiotherapy. Prospective data on stereotactic body radiation therapy (SBRT) are very scarce.To determine the optimal dose regimen for salvage SBRT.The present report concerns the phase 1 part of the GETUG-AFU 31 multicenter open-label study. The main inclusion criteria were histologically proven biochemical recurrence, clinical stage T1-T2 upon relapse, multiparametric magnetic resonance imaging data, prostate-specific antigen (PSA) level ≤10 ng/ml prior to salvage SBRT, PSA doubling time >10 mo, and an International Prostate Symptom Score of ≤12.Five or six fractions of 6 Gy were delivered using focal SBRT.Dose-limiting toxicity (DLT) was defined as grade ≥3 gastrointestinal or genitourinary tract toxicity, or any grade 4 toxicity (according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.03) occurring in the first 18 wk following treatment initiation. A time-to-event continual reassessment method was used to select the dose regimen.Twenty-one patients were treated (median [interquartile range] age: 76.8 yr [72.2-80.8]), including 12 at 6 × 6 dose level. No DLT was observed. The acute grade 2 genitourinary tract toxicity rate was 19%. With a median follow-up of 12.3 mo, the estimated cumulative incidence of late grade 2 genitourinary toxicity was 41.2% (95% confidence interval: 18.1-63.1%). No grade >2 genitourinary toxicity and no grade ≥2 gastrointestinal toxicity were reported. All treated patients were alive and relapse free at the last follow-up.A 6 × 6 Gy dose regimen was selected for our phase 2 study of salvage SBRT. With a short follow-up period, the level of toxicity appears to be acceptable.There is no consensus on the best local treatment for patients with local relapse after radiotherapy for prostate cancer. Prospective data are very scarce. Our early phase trial allowed us to recommend six fractions of 6 Gy using high-precision radiotherapy for further studies.Copyright © 2023 European Association of Urology. Published by Elsevier B.V. All rights reserved.