Department of Radiation Oncology, Johns Hopkins Hospital, Baltimore, Maryland.
Department of Oncology, Oslo University Hospital-Radium Hospital, Oslo, Norway.
Prostate. 2020 Nov;80(15):1322-1327. doi: 10.1002/pros.24059. Epub 2020 Aug 17.
Dose escalated radiation therapy (RT) combined with long-term androgen deprivation therapy (ADT) is a standard of care option for men with high-risk and locally advanced prostate cancer (PCa). However, the optimal dose of escalated RT and ADT is not known. Here we assessed the impact of radiation dose and length of ADT on biochemical recurrence in a multi-institutional cohort stratified by the Cambridge prognostic group (CPG). We hypothesized that radiation dose and length of ADT would impact outcome in similar risk groups of our patients.
Two-hundred and forty-four patients were included, 132 from Oslo University Hospital, Department of Oncology and 112 from Johns Hopkins Hospital, Department of Radiation Oncology. Biochemical recurrence was defined as prostate-specific antigen (PSA) nadir +2 ng/mL. Time to recurrence was estimated using Kaplan-Meier analysis and when stratified by CPG the log-rank test was used. Cox regression analysis was performed to identify factors associated with risk of recurrence. Site of recurrence was investigated.
The median follow-up time was 7.4 years. The vast majority (71%) of patients were classified as high-risk (CPG 4) or very high-risk features (CPG 5). Significantly more PSA recurrences occurred in CPG 5 (41%) compared with CPG 4 (25%) (P = .04) and five-year cumulative recurrence-free survival was lower for CPG 4 and 5 (89% and 68%) compared with CPG 1, 2, and 3 (100%, 100%, and 93%). The recurrence-free survival for CPG 5 was significantly higher for prostate irradiation of 80 Gy as compared with 74 Gy (P = .011). For CPG 4 and 5 no local recurrences were detected in patients receiving 80 Gy. On stepwise Cox regression analysis neither age nor length of ADT were independent prognostic factors for recurrence free survival.
Prostate dose escalation from 74 to 80 Gy decreases risk of recurrence in high-risk PCa. Further studies are needed to identify the optimal combination of ADT and RT.
对于高危和局部晚期前列腺癌（PCa）患者，剂量递增放疗（RT）联合长期雄激素剥夺治疗（ADT）是一种标准的治疗选择。然而，递增 RT 和 ADT 的最佳剂量尚不清楚。在这里，我们评估了辐射剂量和 ADT 长度对按剑桥预后组（CPG）分层的多机构队列中生化复发的影响。我们假设辐射剂量和 ADT 长度会在我们患者的相似风险组中影响结果。
共纳入 244 例患者，其中 132 例来自奥斯陆大学医院肿瘤学系，112 例来自约翰霍普金斯医院放射肿瘤学系。生化复发定义为前列腺特异性抗原（PSA）最低点+2ng/mL。使用 Kaplan-Meier 分析估计复发时间，当按 CPG 分层时，使用对数秩检验。进行 Cox 回归分析以确定与复发风险相关的因素。研究了复发部位。
中位随访时间为 7.4 年。绝大多数（71%）患者被归类为高危（CPG 4）或极高危特征（CPG 5）。CPG 5（41%）的 PSA 复发明显多于 CPG 4（25%）（P=.04），CPG 4 和 5 的五年无复发生存率（89%和 68%）低于 CPG 1、2 和 3（100%、100%和 93%）。与 74Gy 相比，CPG 5 的前列腺照射 80Gy 显著提高了无复发生存率（P=.011）。对于 CPG 4 和 5，接受 80Gy 治疗的患者未检测到局部复发。逐步 Cox 回归分析表明，年龄和 ADT 长度均不是无复发生存的独立预后因素。
高危 PCa 中前列腺剂量从 74Gy 增加到 80Gy 可降低复发风险。需要进一步研究以确定 ADT 和 RT 的最佳组合。
