Mount Vernon Cancer Centre, Northwood, UK; Lismore Base Hospital, North Coast Cancer Institute, New South Wales, Australia.
Mount Vernon Cancer Centre, Northwood, UK.
Radiother Oncol. 2021 Jun;159:67-74. doi: 10.1016/j.radonc.2021.03.018. Epub 2021 Mar 23.
The dominant intraprostatic lesion (DIL) is the commonest site of relapse after single dose high-dose-rate brachytherapy (HDR-BT) for localised prostate cancer. This study investigated toxicity and clinical outcomes of focal dose escalation to the DIL with dose de-escalation to the remaining prostate.
MATERIALS/METHODS: Between November 2012 and July 2016, 50 patients with localised prostate adenocarcinoma received single fraction HDR-BT. 21 Gy was prescribed to the DIL, with two de-escalation prescription schedules for the remaining prostate. Primary outcomes included biochemical no evidence of disease (bNED), local recurrence free survival (LRFS), and metastasis free survival (MFS). Secondary outcomes included late genitourinary, gastrointestinal and sexual toxicity. Kaplan-Meier analyses with log rank tests were used to estimate bNED, LRFS and MFS.
With a median follow up of 70.6 months, 15 patients developed biochemical failure, including 8 in the group that received minor dose de-escalation to the non-DIL prostate (group 1) and 7 in the group that received moderate de-escalation (group 2). Five-year bNED was 88% in group 1 and 76% in group 2 (p = 0.05). Overall 4-year and 5-year FFLF in group 1 was 100% and 96% and in group 2 92% and 84%. These differences were statistically significant (p = 0.03). No acute ≥G3 genitourinary or ≥G2 gastrointestinal toxicity was reported. The median IIEF decreased in the first 6 months improving to a peak median score of 20 at 54 months.
Focal boost to the DIL did not improve biochemical or local control after single-fraction HDR monotherapy compared to what would be expected from 19 Gy single fraction treatment to the whole gland.
在局部前列腺癌单次大剂量率近距离放射治疗（HDR-BT）后，优势前列腺内病变（DIL）是复发的最常见部位。本研究探讨了对 DIL 进行焦点剂量递增，同时对剩余前列腺进行剂量递减的毒性和临床结果。
材料/方法：2012 年 11 月至 2016 年 7 月，50 例局限性前列腺腺癌患者接受单次分割 HDR-BT。21 Gy 用于 DIL，剩余前列腺采用两种剂量递减方案。主要结果包括生化无疾病证据（bNED）、局部无复发生存率（LRFS）和无转移生存率（MFS）。次要结果包括晚期泌尿生殖系统、胃肠道和性功能毒性。采用对数秩检验的 Kaplan-Meier 分析估计 bNED、LRFS 和 MFS。
中位随访 70.6 个月后，15 例患者发生生化失败，其中 8 例在接受非 DIL 前列腺轻度剂量递减（组 1）的患者中，7 例在接受中度剂量递减（组 2）的患者中。组 1 的 5 年 bNED 为 88%，组 2 为 76%（p=0.05）。组 1 的总 4 年和 5 年 FFLF 为 100%和 96%，组 2 为 92%和 84%。这些差异具有统计学意义（p=0.03）。未报告急性≥G3 泌尿生殖系统或≥G2 胃肠道毒性。IIEF 中位数在最初 6 个月内下降，在 54 个月时达到 20 的峰值中位数评分。
与 19 Gy 单次全腺治疗相比，单次分割 HDR 单药治疗后，对 DIL 进行局部强化治疗并未改善生化或局部控制。
