Department of Neurology, Sun Yat-Sen Memorial Hospital, Guangzhou, Guangdong Province, China.
Department of Radiology, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong Province, China.
Int J Radiat Oncol Biol Phys. 2018 Mar 1;100(3):621-629. doi: 10.1016/j.ijrobp.2017.11.023. Epub 2017 Nov 21.
To identify the predictive and prognostic factors for a decrease or recurrence of brain edema in patients who developed radiation-induced brain necrosis (RN) after radiation therapy for nasopharyngeal carcinoma (NPC) and who received bevacizumab monotherapy.
This was a retrospective study. The charts of 50 patients who were diagnosed with RN after radiation therapy for NPC, treated with bevacizumab, and followed up for 6 months were reviewed. Clinical data of these patients were collected, and their brain edema volume before bevacizumab administration, after bevacizumab administration, at 3-month follow-up, and at 6-month follow-up was evaluated on the basis of brain magnetic resonance imaging findings. The baseline serum vascular endothelial growth factor levels of 15 patients were measured by enzyme-linked immunosorbent assay. A random forests model was developed for statistical analysis.
The median percentage of decrease in RN volume shown on T2-weighted fluid-attenuated inversion recovery images at the end of bevacizumab therapy was 72.6% (interquartile range, 34.5% to 89.5%; P < .001). Twelve of these 50 patients (24.0%) did not have an effective response, and 38 patients (76.0%) showed an effective response after bevacizumab administration. Fifteen of the 38 patients showed RN recurrence. According to the random forests model the maximum radiation dose of the temporal lobe (D of the temporal lobe) was a highly ranked predictor for the therapeutic effect of bevacizumab. The duration between radiation therapy and bevacizumab treatment and the duration between radiation therapy and RN diagnosis were highly ranked predictors for RN recurrence after bevacizumab treatment.
Prediction models for the therapeutic effect of bevacizumab in RN patients were developed, using the random forests model. Bevacizumab might be more effective in patients with a lower maximum radiation dose to the temporal lobe.
确定接受贝伐单抗单药治疗的鼻咽癌（NPC）放射治疗后发生放射性脑坏死（RN）并出现脑水肿消退或复发患者的预测和预后因素。
这是一项回顾性研究。对 50 例 NPC 放射治疗后诊断为 RN 并接受贝伐单抗治疗且随访 6 个月的患者的病历进行了回顾性分析。收集这些患者的临床资料，并根据脑磁共振成像（MRI）检查结果评估贝伐单抗治疗前、治疗后、3 个月随访和 6 个月随访时的脑水肿体积。通过酶联免疫吸附试验测定 15 例患者的基线血清血管内皮生长因子水平。采用随机森林模型进行统计学分析。
贝伐单抗治疗结束时 T2 加权液体衰减反转恢复（FLAIR）图像上 RN 体积的中位数百分比下降率为 72.6%（四分位距 34.5%~89.5%；P<0.001）。50 例患者中 12 例（24.0%）无有效反应，38 例（76.0%）贝伐单抗治疗后有有效反应。38 例中有 15 例出现 RN 复发。根据随机森林模型，颞叶最大照射剂量（D of the temporal lobe）是贝伐单抗治疗效果的一个高度相关预测因素。放射治疗与贝伐单抗治疗之间的时间间隔以及放射治疗与 RN 诊断之间的时间间隔是贝伐单抗治疗后 RN 复发的高度相关预测因素。
采用随机森林模型建立了贝伐单抗治疗 RN 患者疗效的预测模型。贝伐单抗可能对颞叶受照剂量较低的患者更有效。
