Department of Radiation Oncology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.
Department of Medical Oncology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.
Clin Lung Cancer. 2018 May;19(3):260-269.e3. doi: 10.1016/j.cllc.2017.12.003. Epub 2017 Dec 14.
Patients with small-cell lung cancer (SCLC) have a high incidence of occult brain metastases and are often treated with prophylactic cranial irradiation (PCI). Despite a small survival advantage in some studies, the role of PCI in extensive stage SCLC remains controversial. We used the National Cancer Database to assess survival of patients with metastatic SCLC treated with PCI.
Metastatic SCLC patients without brain metastases were identified. To minimize treatment selection bias, patients with an overall survival (OS) < 6 months were excluded. Cox regression identified variables associated with OS. Patients were propensity score-matched on factors associated with receipt of PCI or OS. The effect of PCI on OS was examined using Kaplan-Meier estimates.
In the overall cohort (n = 4257), treatment with PCI (n = 473) was associated with improved survival (hazard ratio, 0.66; 95% confidence interval, 0.60-0.74; P < .0001). Comparisons of propensity score-matched cohorts revealed a significant survival benefit for patients who received PCI in median OS (13.9 vs. 11.1 months; P < .0001), as well as 1- and 2-year OS (61.2% vs. 44.0% and 19.8% vs. 11.5%, respectively; P < .0001). This survival benefit persisted even after excluding patients who survived < 9 months (median: 15.3 vs. 12.9 months; P < .0001). In multivariable analysis, predictors of receipt of PCI were Caucasian race, younger age, and lower Charlson-Deyo score.
Using a modern population-based data set, we showed that metastatic SCLC patients treated with PCI have significantly improved OS. This large retrospective study helps address the conflicting prospective data.
小细胞肺癌（SCLC）患者隐匿性脑转移发生率较高，常采用预防性颅脑照射（PCI）治疗。尽管一些研究显示 PCI 可使患者的生存获益略有增加，但 PCI 在广泛期 SCLC 中的作用仍存在争议。本研究利用国家癌症数据库评估了接受 PCI 治疗的转移性 SCLC 患者的生存情况。
本研究纳入了无脑转移的转移性 SCLC 患者。为了尽量减少治疗选择偏倚，排除了总生存（OS）<6 个月的患者。Cox 回归分析确定了与 OS 相关的变量。采用倾向评分匹配分析了与 PCI 或 OS 相关的因素。采用 Kaplan-Meier 估计法评估了 PCI 对 OS 的影响。
在全队列（n=4257）中，接受 PCI 治疗（n=473）与生存获益相关（风险比，0.66；95%置信区间，0.60-0.74；P<0.0001）。倾向评分匹配队列的比较结果显示，接受 PCI 治疗的患者中位 OS （13.9 个月比 11.1 个月；P<0.0001）、1 年和 2 年 OS（61.2%比 44.0%和 19.8%比 11.5%）均显著获益（P<0.0001）。即使排除生存时间<9 个月的患者（中位生存时间：15.3 个月比 12.9 个月；P<0.0001），这一生存获益仍存在。多变量分析显示，接受 PCI 的预测因素为白种人、年龄较轻和Charlson-Deyo 评分较低。
本研究利用现代基于人群的数据集表明，接受 PCI 治疗的转移性 SCLC 患者的 OS 显著改善。这项大型回顾性研究有助于解决前瞻性研究数据的矛盾。
