Eaton Bree R, LaRiviere Michael J, Kim Sungjin, Prabhu Roshan S, Patel Kirtesh, Kandula Shravan, Oyesiku Nelson, Olson Jeffrey, Curran Walter, Shu Hui-Kuo, Crocker Ian
Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA, USA,
J Neurooncol. 2015 May;123(1):103-11. doi: 10.1007/s11060-015-1767-4. Epub 2015 Apr 11.
The purpose of this study is to compare the safety and efficacy of single fraction radiosurgery (SFR) with hypofractionated radiosurgery (HR) for the adjuvant treatment of large, surgically resected brain metastases. Seventy-five patients with 76 resection cavities ≥ 3 cm received 15 Gray (Gy) × 1 SFR (n = 40) or 5-8 Gy × 3-5 HR (n = 36). Cumulative incidence of local failure (LF) and radiation necrosis (RN) was estimated accounting for death as a competing risk and compared with Gray's test. The effect of multiple covariates was evaluated with the Fine-Gray proportional hazards model. The most common HR dose-fractionation schedules were 6 Gy × 5 (44%), 7-8 Gy × 3 (36%), and 6 Gy × 4 (8%). The median follow-up was 11 months (range 2-71). HR patients had larger median resection cavity volumes (24.0 vs. 13.3 cc, p < 0.001), planning target volumes (PTV) (37.7 vs. 20.5 cc, p < 0.001), and cavity to PTV expansion margins (2 vs. 1.5 mm, p = 0.002) than SFR patients. Cumulative incidence of LF (95% CI) at 6 and 12-months for HR versus SFR was 18.9% (0.07-0.34) versus 15.9% (0.06-0.29), and 25.6% (0.12-0.42) versus 27.2% (0.14-0.42), p = 0.80. Cumulative incidence of RN (95% CI) at 6 and 12 months for HR vs. SFR was 3.3% (0.00-0.15) versus 10.7% (0.03-0.23), and 10.3% (0.02-0.25) versus 19.2% (0.08-0.34), p = 0.28. On multivariable analysis, SFR was significantly associated with an increased risk of RN, with a HR of 3.81 (95% CI 1.04-13.93, p = 0.043). Hypofractionated radiosurgery may be the more favorable treatment approach for radiosurgery of cavities 3-4 cm in size and greater.
本研究旨在比较单次分割放射外科治疗（SFR）与超分割放射外科治疗（HR）辅助治疗大型手术切除脑转移瘤的安全性和有效性。75例有76个切除腔≥3 cm的患者接受了15格雷（Gy）×1次的SFR（n = 40）或5 - 8 Gy×3 - 5次的HR（n = 36）。估计局部失败（LF）和放射性坏死（RN）的累积发生率，并将死亡作为竞争风险进行考量，采用格雷检验进行比较。使用Fine - Gray比例风险模型评估多个协变量的影响。最常见的HR剂量分割方案为6 Gy×5次（44%）、7 - 8 Gy×3次（36%）和6 Gy×4次（8%）。中位随访时间为11个月（范围2 - 71个月）。HR组患者的中位切除腔体积（24.0 vs. 13.3 cc，p < 0.001）、计划靶体积（PTV）（37.7 vs. 20.5 cc，p < 0.001）以及腔到PTV的外放边界（2 vs. 1.5 mm，p = 0.002）均大于SFR组患者。HR组与SFR组在6个月和12个月时LF的累积发生率（95%CI）分别为18.9%（0.07 - 0.34）对15.9%（0.06 - 0.29），以及25.6%（0.12 - 0.42）对27.2%（0.14 - 0.42），p = 0.80。HR组与SFR组在6个月和12个月时RN的累积发生率（95%CI）分别为3.3%（0.00 - 0.15）对10.7%（0.03 - 0.23），以及10.3%（0.02 - 0.25）对19.2%（0.08 - 0.34），p = 0.28。多变量分析显示，SFR与RN风险增加显著相关，风险比为3.81（95%CI 1.04 - 13.93，p = 0.043）。对于大小为3 - 4 cm及更大的切除腔进行放射外科治疗，超分割放射外科治疗可能是更有利的治疗方法。
