Kruser Tim J, Tome Wolfgang A, Seo Songwon, Kuo John S, Turski Patrick A, Chappell Richard J, Scrimger Rufus A, Mehta Minesh P
Departments of Human Oncology.
Dept. of Biostatistics and Medical Informatics.
J Radiosurg SBRT. 2011;1(3):203-211.
Few series analyzing prognostic fac tors predicting for obliteration of arteriovenous malformations (AVMs) following linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) have been reported. We analyzed prognostic variables, outcomes, and toxicities in 88 patients undergoing LINAC-based SRS for AVMs.
Following IRB approval, patient records were retrospectively analyzed to identify independent predictors of complete response (obliteration) (CR) and time-to-CR. The majority of AVMs were treated using multiple isocenters and non-coplanar arcs. The median AVM volume was 2.67 cm (0.05 - 33.51). Median marginal and maximal doses were 17 (12-24) and 26.1 Gy (15-40), with a median prescription isodose surface of 65%.
Spetzler-Martin (SM) grade was determined for 86 patients and was: I-3 pts (3%); II-23 pts (27%); III-45 pts (52%); IV-13 pts (15%); V-2 pts (2%).Of 80 patients with follow-up imaging, 44 (55%) had documented complete responses (CR). Kaplan-Meier estimate probability for CR at 4 years was 62% (95% CI: 0.50, 0.74). Median time to CR was 3 years (95% CI: 2.08, 3.17). Multivariate analysis demonstrated the Spetzler-Martin grade (OR=0.14 for grade III vs. grade I-II; p=0.004 and OR 0.07 for grade IV-V vs. grade I-II; p=0.002) and dichotomized marginal dose > 17 Gy (OR=4.19; p=0.01) to be significantly associated with CR.
This report demonstrates that for LINAC-based SRS of AVM, marginal dose and Spetzler-Martin grade are strong predictors of complete AVM obliteration.
很少有系列研究分析基于直线加速器（LINAC）的立体定向放射外科治疗（SRS）后动静脉畸形（AVM）闭塞的预测预后因素。我们分析了88例接受基于LINAC的AVM-SRS治疗患者的预后变量、结局和毒性。
经机构审查委员会（IRB）批准后，对患者记录进行回顾性分析，以确定完全缓解（闭塞）（CR）和达到CR的时间的独立预测因素。大多数AVM采用多个等中心和非共面弧进行治疗。AVM的中位体积为2.67 cm³（0.05 - 33.51）。中位边缘剂量和最大剂量分别为17（12 - 24）Gy和26.1 Gy（15 - 40），中位处方等剂量面为65%。
86例患者确定了Spetzler-Martin（SM）分级，分别为：I级-3例（3%）；II级-23例（27%）；III级-45例（52%）；IV级-13例（15%）；V级-2例（2%）。在80例有随访影像学检查的患者中，44例（55%）记录有完全缓解（CR）。4年时CR的Kaplan-Meier估计概率为62%（95%CI：0.50，0.74）。达到CR的中位时间为3年（95%CI：2.08，3.17）。多变量分析表明，Spetzler-Martin分级（III级与I-II级相比，OR = 0.14；p = 0.004；IV-V级与I-II级相比，OR = 0.07；p = 0.002）以及二分边缘剂量>17 Gy（OR = 4.19；p = 0.01）与CR显著相关。
本报告表明，对于基于LINAC的AVM-SRS，边缘剂量和Spetzler-Martin分级是AVM完全闭塞的有力预测因素。
