Recursive Partitioning Analysis for the Prediction of Stereotactic Radiosurgery Brain Metastases Lesion Control. (19th February 2013)

• Record Type: Journal Article
• Authors: Rodrigues, George; Zindler, Jaap; Warner, Andrew; Lagerwaard, Frank
• Is Part Of: Oncologist. Volume 18:Number 3(2013)
• Page Start: 330
• Page End: 335
• Publication Date: 2013-02-19
• Subjects: Brain metastases -- Stereotactic radiosurgery -- Recursive partitioning analysis -- Predictive modeling -- Local control; Oncology -- Periodicals; Tumors -- Periodicals; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Oncology; Tumors; Neoplasms; Electronic journals; Periodicals; Periodicals; 616.994
• DOI: 10.1634/theoncologist.2012-0316
• Languages: English
• ISSNs: 1083-7159

Abstract

Abstract : Learning Objectives: Describe the results of a new recursive partitioning analysis (RPA) predicting for SRS lesion control. Discuss the SRS lesion in the light of other literature assessing predictors of lesion control in SRS for brain metastases. Purpose: The objective of this investigation was to identify independent pretreatment factors that predict for control of local brain metastases (BM) in a large single‐institution series of patients receiving stereotactic radiosurgery (SRS). Recursive partitioning analysis was used to potentially identify a class of patients with durable lesion control characteristics. Methods: A retrospective SRS database containing baseline characteristics, treatment details, and follow‐up data of newly diagnosed patients with 1–3 BM (on magnetic resonance imaging) treated with linear accelerator‐based SRS was created. Three study endpoints were used: time to progression (primary endpoint, individual lesion progression; n = 536), time to first progression (secondary endpoint, first lesion progression on an individual patient basis; n = 380), and overall survival (secondary endpoint; n = 380). Recursive partitioning analysis (RPA) was performed to identify predictors of time to progression. Results: Multivariable analysis demonstrated that lesion aspect/phenotype and radiotherapy schedule were independent factors associated with both progression outcomes. Presence of tumor necrosis was found to be associated with a significant hazard of progression (hazard ratio >3), whereas use of the most intense radiotherapy fractionation schedule (21 Gy in one fraction) was associated with significant reductions in progression (hazard ratio <0.3). RPA using SRS dose and lesion aspect/phenotype was created and described three distinct prognostic groups. Conclusions: RPA of a large retrospective database of patients receiving SRS confirmed previous observations regarding the importance of SRS dose and lesion aspect/phenotype in lesion control and overall survival. The SRS lesion analysis may help to stratify future clinical trials and better define patient care options and prognosis. Abstract : This study aimed to identify independent pretreatment factors that predict for control of local brain metastases in a large single‐institution series of patients with brain metastases who received stereotactic radiosurgery. Lesion aspect/phenotype and radiotherapy schedule were independent factors associated with progression outcomes. Abstract : 摘要 背景 . 在一家大型医疗中心接受立体定向放射外科治疗（SRS）的患者中调查SRS控制局部脑转移灶（BM）的治疗前独立预测因素。尝试采用递归分割分析识别具有难治病灶控制特征的患者。 方法 . 建立回顾性SRS数据库，纳入对象为核磁共振成像显示1~3个BM，并接受基于线性加速器SRS治疗的新诊断患者，纳入数据包括基线特征、治疗细节及随访数据。采用3个研究终点：至进展时间（主要研究终点，单个病灶进展； n =536）、至首次进展时间（次要研究终点，基于个例患者的至首次病灶进展时间； n = 380）及总生存（次要研究终点； n = 380）。采用递归分割分析（RPA）明确至进展时间的预测因素。 结果 . 多变量分析显示，病灶特征/表型与放疗日程安排是疾病进展转归的2项独立预测因素。肿瘤坏死与显著的进展风险相关（风险比>3），而采用最密集的分割放疗日程（每次21Gy）与进展风险显著降低相关（风险比<0.3）。创建基于SRS剂量与病灶特征/表型的RPA分析，对3个不同的预后组进行了描述。 结论 . 对一项大型SRS患者回顾性研究数据库进行的RPA进一步证实了既往的研究结果，SRS剂量与病灶特征/表型对病灶控制及总生存至关重要。SRS病灶分析有助于对今后临床研究进行分层，更好地定义患者的治疗选择及预后。