Department of Radiotherapy, University Medical Center Utrecht, the Netherlands.
Department of Radiotherapy, University Medical Center Utrecht, the Netherlands.
Int J Radiat Oncol Biol Phys. 2020 May 1;107(1):126-135. doi: 10.1016/j.ijrobp.2020.01.023. Epub 2020 Jan 30.
Most patients with local prostate cancer recurrence after radiation therapy undergo palliative androgen deprivation therapy because whole-gland salvage treatments have a high risk of severe toxicity. Focal treatment reduces this risk while offering a second opportunity for cure. We report updated outcomes of ultrafocal salvage high-dose-rate brachytherapy (HDR-BT).
Prospectively collected data from the first 50 treated patients were analyzed. Disease status was assessed by 3T multiparametric magnetic resonance imaging (MRI), 18F-Choline or 68Ga-prostate-specific membrane antigen positron emission tomography/computed tomography, and systematic or tumor-targeted biopsies. Ultrafocal salvage HDR-BT (1 × 19 Gy) was performed by implanting the clinical target volume (CTV: gross tumor volume + 5 mm margin) under fused transrectal ultrasound/MRI guidance. Follow-up included toxicity grading (using Common Terminology Criteria for Adverse Events 4.0), quality of life assessment, and prostate-specific antigen (PSA) testing.
Median follow-up was 31 months. Median CTV D95% was 18.8 Gy. We observed 2% grade 3 genitourinary toxicity, no grade 3 gastrointestinal toxicity, and 22% newly developed grade 3 erectile dysfunction. Five of 13 patients (38%) with self-reported pretreatment potency (International Index of Erectile Function >17) remained potent. Clinically relevant quality of life deterioration was reported for only 6 of 31 items and was not statistically significant. Biochemical failure (nadir + 2) occurred in 26 patients. Among intraprostatic recurrences, 73% were in field. After 2.5 years, biochemical disease-free survival was 51% (95% confidence interval, 37%-69%), metastases-free survival was 75% (64%-89%), androgen deprivation therapy-free survival was 90% (82%-99%), and overall survival was 98% (94%-100%). Presalvage PSA, CTV size, and stage ≥T3 were significantly associated with biochemical failure. Higher-risk patients (stage ≥T3, PSA ≥10, or PSA double time ≤9 months) had 25% biochemical disease-free survival at 2.5 years versus 71% for lower-risk patients.
At this early stage, MRI-guided ultrafocal HDR-BT seems to be a safe salvage treatment option, with acceptable biochemical control in a well-selected group of patients and potential for effectively postponing androgen deprivation therapy.
大多数接受放射治疗后局部前列腺癌复发的患者接受姑息性去势雄激素剥夺治疗，因为全腺体挽救治疗有发生严重毒性的高风险。局部治疗降低了这种风险，同时提供了第二次治愈的机会。我们报告了超局部挽救性高剂量率近距离治疗（HDR-BT）的最新结果。
分析了前 50 名接受治疗的患者的前瞻性收集数据。通过 3T 多参数磁共振成像（MRI）、18F-胆碱或 68Ga-前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描以及系统或肿瘤靶向活检评估疾病状态。在融合经直肠超声/MRI 引导下，对临床靶区（CTV：大体肿瘤体积+5mm 边界）进行超局部挽救性 HDR-BT（1×19Gy）。随访包括毒性分级（使用不良事件通用术语标准 4.0）、生活质量评估和前列腺特异性抗原（PSA）检测。
中位随访时间为 31 个月。CTV D95%的中位值为 18.8Gy。我们观察到 2%的 3 级泌尿生殖系统毒性，无 3 级胃肠道毒性，22%新发生的 3 级勃起功能障碍。13 名有自我报告治疗前勃起功能（国际勃起功能指数>17）的患者中有 5 名仍有勃起功能。只有 31 项中的 6 项报告了临床相关的生活质量恶化，且无统计学意义。26 名患者发生生化失败（最低点+2）。在前列腺内复发中，73%发生在野内。2.5 年后，生化无疾病生存率为 51%（95%置信区间，37%-69%），无转移生存率为 75%（64%-89%），无雄激素剥夺治疗生存率为 90%（82%-99%），总生存率为 98%（94%-100%）。挽救前 PSA、CTV 大小和≥T3 期与生化失败显著相关。高风险患者（≥T3 期、PSA≥10 或 PSA 倍增时间≤9 个月）在 2.5 年时的生化无疾病生存率为 25%，而低风险患者为 71%。
在这个早期阶段，MRI 引导的超局部 HDR-BT 似乎是一种安全的挽救治疗选择，在选择良好的患者群体中具有可接受的生化控制效果，并有可能有效推迟雄激素剥夺治疗。
