Departments of Radiation Oncology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland.
Strahlenther Onkol. 2013 Sep;189(9):765-70. doi: 10.1007/s00066-013-0409-z. Epub 2013 Aug 11.
Tumor bed stereotactic radiosurgery (SRS) after resection of brain metastases is a new strategy to delay or avoid whole-brain irradiation (WBRT) and its associated toxicities. This retrospective study analyzes results of frameless image-guided linear accelerator (LINAC)-based SRS and stereotactic hypofractionated radiotherapy (SHRT) as adjuvant treatment without WBRT.
Between March 2009 and February 2012, 44 resection cavities in 42 patients were treated with SRS (23 cavities) or SHRT (21 cavities). All treatments were delivered using a stereotactic LINAC. All cavities were expanded by ≥ 2 mm in all directions to create the clinical target volume (CTV).
The median planning target volume (PTV) for SRS was 11.1 cm(3). The median dose prescribed to the PTV margin for SRS was 17 Gy. Median PTV for SHRT was 22.3 cm(3). The fractionation schemes applied were: 4 fractions of 6 Gy (5 patients), 6 fractions of 4 Gy (6 patients) and 10 fractions of 4 Gy (10 patients). Median follow-up was 9.6 months. Local control (LC) rates after 6 and 12 months were 91 and 77 %, respectively. No statistically significant differences in LC rates between SRS and SHRT treatments were observed. Distant brain control (DBC) rates at 6 and 12 months were 61 and 33 %, respectively. Overall survival (OS) at 6 and 12 months was 87 and 63.5 %, respectively, with a median OS of 15.9 months. One patient treated by SRS showed symptoms of radionecrosis, which was confirmed histologically.
Frameless image-guided LINAC-based adjuvant SRS and SHRT are effective and well tolerated local treatment strategies after resection of brain metastases in patients with oligometastatic disease.
脑转移瘤切除术后肿瘤床立体定向放射外科（SRS）是一种延迟或避免全脑放疗（WBRT）及其相关毒性的新策略。本回顾性研究分析了无 WBRT 辅助治疗的无框架图像引导直线加速器（LINAC）SRS 和立体定向亚分次放疗（SHRT）的结果。
2009 年 3 月至 2012 年 2 月，42 例患者的 44 个切除腔接受了 SRS（23 个腔）或 SHRT（21 个腔）治疗。所有治疗均采用立体定向 LINAC 进行。所有腔均向各个方向扩大≥2mm 以创建临床靶区（CTV）。
SRS 的中位计划靶区（PTV）为 11.1cm3。SRS 中 PTV 边缘规定的中位剂量为 17Gy。SHRT 的中位 PTV 为 22.3cm3。应用的分割方案为：4 次 6Gy（5 例）、6 次 4Gy（6 例）和 10 次 4Gy（10 例）。中位随访时间为 9.6 个月。6 个月和 12 个月时的局部控制（LC）率分别为 91%和 77%。SRS 和 SHRT 治疗的 LC 率无统计学差异。6 个月和 12 个月时的远处脑控制（DBC）率分别为 61%和 33%。6 个月和 12 个月的总生存率（OS）分别为 87%和 63.5%，中位 OS 为 15.9 个月。1 例接受 SRS 治疗的患者出现放射性坏死症状，经组织学证实。
无框架图像引导 LINAC 辅助 SRS 和 SHRT 是寡转移疾病患者脑转移瘤切除术后有效且耐受性良好的局部治疗策略。
