Department of Human Oncology, University of Wisconsin Hospital and Clinics, Paul P Carbone Cancer Center, Madison, WI, USA.
Anticancer Res. 2013 Jun;33(6):2611-8.
This retrospective analysis evaluates feasibility of wide-field re-irradiation using pulsed reduced dose rate (PRDR) technique in patients with recurrent ependymoma. PRDR employs a dose rate of 6 cGy/min, as opposed to 400-600 cGy/min for conventional radiation, allowing for enhanced normal tissue repair.
Five patients with recurrent ependymoma having eight lesions (two brain, six spinal cord) were treated with PRDR. Progression-free survival (PFS) and overall survival (OS) were estimated by Kaplan Meier method.
The median interval between two radiation courses was 58 months (range: 32-212 months). The median PRDR dose was 40 Gy (range: 30.6-54 Gy) with a median cumulative lifetime dose of 105.2 Gy (range: 90-162.4 Gy). At a median post-PRDR follow-up of 64 months, estimated 4-year OS and PFS from PRDR was 60% and 35.7%, respectively. None of the patients developed necrosis on serial magnetic resonance imaging scans, and only one patient had progressive mild radiculopathy.
In patients with large-volume recurrent ependymoma, re-irradiation with wide-field PRDR is a feasible option.
本回顾性分析评估了在复发性室管膜瘤患者中使用脉冲降剂量率（PRDR）技术进行大野再放疗的可行性。PRDR 采用的剂量率为 6cGy/min，而传统放疗的剂量率为 400-600cGy/min，从而允许更好地修复正常组织。
5 名复发性室管膜瘤患者（8 个病灶，2 个脑部，6 个脊髓）接受了 PRDR 治疗。采用 Kaplan-Meier 法估计无进展生存期（PFS）和总生存期（OS）。
两次放疗之间的中位间隔时间为 58 个月（范围：32-212 个月）。PRDR 的中位剂量为 40Gy（范围：30.6-54Gy），累积终生剂量的中位值为 105.2Gy（范围：90-162.4Gy）。在 PRDR 后中位随访 64 个月时，PRDR 的估计 4 年 OS 和 PFS 分别为 60%和 35.7%。没有患者在连续磁共振成像扫描中出现坏死，只有 1 名患者出现进行性轻度放射性神经病。
对于大体积复发性室管膜瘤患者，采用大野 PRDR 再放疗是一种可行的选择。
