Department of Radiation Oncology, Seoul National University Hospital, Seoul, South Korea.
Department of Nuclear Medicine, Seoul National University Hospital, Seoul, South Korea; Department of Molecular Medicine and Biopharmaceutical Science, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea.
Radiother Oncol. 2020 Feb;143:81-87. doi: 10.1016/j.radonc.2020.01.009. Epub 2020 Feb 7.
To identify risk factors for developing symptomatic brain metastases and evaluate the impact of prophylactic cranial irradiation (PCI) on brain metastasis-free survival (BMFS) and overall survival (OS) in extensive disease small cell lung cancer (ED-SCLC).
Among 190 patients diagnosed with ED-SCLC who underwent FDG PET/CT and brain Magnetic Resonance Imaging (MRI) prior to treatment, 53 (27.9%) received PCI while 137 (72.1%) did not. Prognostic index predicting a high risk of symptomatic brain metastases was calculated for the group without receiving PCI (observation group, n = 137) with Cox regression model.
Median follow-up time was 10.6 months. Multivariate Cox regression showed that the following three factors were associated with a high risk of symptomatic brain metastases: the presence of extrathoracic metastases (p = 0.004), hypermetabolism of bone marrow or spleen on FDG PET (p < 0.001), and high neutrophil-to-lymphocyte ratio (p = 0.018). PCI significantly improved BMFS in high-risk patients (1-year rate: 94.7% vs. 62.1%, p = 0.001), but not in low-risk patients (1-year rate: 100.0% vs. 87.7%, p = 0.943). However, PCI did not improve OS in patients at high risk for symptomatic brain metastases (1-year rate: 65.2% vs. 50.0%, p = 0.123).
Three prognostic factors (the presence of extrathoracic metastases, hypermetabolism of bone marrow or spleen on FDG PET, and high neutrophil-to-lymphocyte ratio) were associated with a high risk of symptomatic brain metastases in ED-SCLC. PCI was beneficial for patients at a high risk of symptomatic brain metastases in terms of BMFS, but not OS. Thus, selective use of PCI in ED-SCLC according to the risk stratification is recommended.
确定发展为有症状脑转移的风险因素，并评估预防性颅脑照射（PCI）对广泛期小细胞肺癌（ED-SCLC）患者无脑转移生存（BMFS）和总生存（OS）的影响。
在 190 例接受 FDG PET/CT 和脑部磁共振成像（MRI）检查的 ED-SCLC 患者中，53 例（27.9%）接受了 PCI，137 例（72.1%）未接受。采用 Cox 回归模型计算未接受 PCI（观察组，n=137）患者发生有症状脑转移的高危预测指数。
中位随访时间为 10.6 个月。多因素 Cox 回归显示，以下三个因素与发生有症状脑转移的高风险相关：存在胸外转移（p=0.004）、FDG PET 骨髓或脾脏高代谢（p<0.001）和高中性粒细胞与淋巴细胞比值（p=0.018）。PCI 显著改善高危患者的 BMFS（1 年率：94.7%比 62.1%，p=0.001），但对低危患者无影响（1 年率：100.0%比 87.7%，p=0.943）。然而，PCI 并未改善高危患者的 OS（1 年率：65.2%比 50.0%，p=0.123）。
在 ED-SCLC 中，三个预后因素（存在胸外转移、FDG PET 骨髓或脾脏高代谢、高中性粒细胞与淋巴细胞比值）与有症状脑转移的高风险相关。PCI 对有症状脑转移高危患者的 BMFS 有益，但对 OS 无益。因此，建议根据风险分层选择性地在 ED-SCLC 中应用 PCI。
