Department of Radiation Oncology, Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN.
Department of Medical and Molecular Genetics, Collaborative Core for Cancer Bioinformatics, Indianapolis, IN.
Clin Lung Cancer. 2019 May;20(3):186-193.e3. doi: 10.1016/j.cllc.2018.12.016. Epub 2018 Dec 29.
INTRODUCTION/BACKGROUND: Many patients with early stage non-small-cell lung cancer (ES-NSCLC) undergoing stereotactic body radiation therapy (SBRT) develop metastases, which is associated with poor outcomes. We sought to identify factors predictive of metastases after lung SBRT and created a risk stratification tool.
We included 363 patients with ES-NSCLC who received SBRT; the median follow-up was 5.8 years. The following patient and tumor factors were retrospectively analyzed for their association with metastases (defined as nodal and/or distant failure): gender; age; lobe involved; centrality; previous NSCLC; smoking status; gross tumor volume (GTV); T-stage; histology; dose; minimum, maximum, and mean GTV dose; and parenchymal lung failure. A metastasis risk-score linear-model using beta coefficients from a multivariate Cox model was built.
A total of 111 (27.3%) of 406 lesions metastasized. GTV and dose were significantly associated with metastases on univariate and multivariate Cox proportional hazards modeling (P < .001 and hazard ratio [HR], 1.02 per mL; P < .05 and HR, 0.99 per Gy, respectively). Histology, T-stage, centrality, lung parenchymal failures, and previous NSCLC were not associated with development of metastasis. A metastasis risk-score model using GTV and prescription dose was built: risk score = (0.01611 × GTV) - (0.00525 × dose [BED]). Two risk-score cutoffs separating the cohort into low-, medium-, and high-risk subgroups were examined. The risk score identified significant differences in time to metastases between low-, medium-, and high-risk patients (P < .001), with 3-year estimates of 81.1%, 63.8%, and 38%, respectively.
GTV and radiation dose are associated with time to metastasis and may be used to identify patients at higher risk of metastasis after lung SBRT.
介绍/背景：许多接受立体定向体部放射治疗（SBRT）的早期非小细胞肺癌（ES-NSCLC）患者会发生转移，这与不良预后相关。我们试图确定 SBRT 后发生转移的预测因素，并创建了一种风险分层工具。
我们纳入了 363 名接受 SBRT 的 ES-NSCLC 患者；中位随访时间为 5.8 年。回顾性分析以下患者和肿瘤因素与转移（定义为淋巴结和/或远处失败）的相关性：性别；年龄；受累肺叶；中心性；既往 NSCLC；吸烟状态；大体肿瘤体积（GTV）；T 分期；组织学；剂量；最小、最大和平均 GTV 剂量；以及肺实质失败。使用多变量 Cox 模型的β系数构建转移风险评分线性模型。
406 个病灶中有 111 个（27.3%）发生转移。GTV 和剂量在单变量和多变量 Cox 比例风险模型中与转移显著相关（P<0.001 和危险比[HR]，每毫升增加 1.02；P<0.05 和 HR，每 Gy 减少 0.99）。组织学、T 分期、中心性、肺实质失败和既往 NSCLC 与转移的发生无关。建立了使用 GTV 和处方剂量的转移风险评分模型：评分=（0.01611×GTV）-（0.00525×剂量[BED]）。两个风险评分截点将队列分为低、中、高风险亚组进行检查。风险评分在低、中、高风险患者之间的转移时间上显示出显著差异（P<0.001），3 年估计值分别为 81.1%、63.8%和 38%。
GTV 和辐射剂量与转移时间相关，可用于识别 SBRT 后发生转移风险较高的患者。
