X刀放射外科治疗多发脑转移瘤效果及影响因素

THERAPEUTIC EFFICACY OF TREATING MULTIPLE BRAIN MATASTASES WITH LINEAR ACCELERATOR RADIOSURGERY ALONE

目的评估单独采用X刀放射外科治疗多发脑转移瘤的疗效及其影响因素。方法133例多发脑转移瘤病人单独接受X刀放射外科治疗,不合并全脑放射治疗。原发恶性肿瘤包括非小细胞肺癌、乳癌及其他。平均脑转移瘤的个数为4.4个（2-12个）,平均肿瘤总体积为16.2 cm^3（1.0-53.0 cm^3）,平均边缘放射剂量16.7 Gy,平均随访时间7.0月。结果中位生存时间为9.0月。Cox回归分析显示,肿瘤总体积、RPA等级、边缘放射剂量为显著预后因子;脑转移瘤的个数、年龄、中心剂量则无统计学差异。结论肿瘤总体积、RPA等级为多发颅内转移瘤显著预后因子。肿瘤总体积应该作为放射外科的选择标准,而不是转移瘤的个数。多发脑转移瘤单独采用X刀放射外科治疗可以获得满意的疗效,而是否有必要行全脑放射治疗,值得商榷。

Objective To evaluate the therapeutic efficacy and affecting factors of linear accelerator radiosurgery in treating multiple brain metastases. Methods One hundred and thirty-three patients with multiple brain metastases underwent linear accelerator radiosurgery without whole brain radiotherapy （WBRT）. The primary malignancies including non-small-cell lung cancer, breast carcinoma, and others. The mean number of brain metastases was 4.4 （range 2--12） with a mean total treatment volume of 16. 2 cm^3 （range 1. 0--53.0 cm^3）. The mean marginal radiosurgery dose was 16. 7 Gy. The mean follow-up was 7. 0 months. Results The median overall survival after linear accelerator radiosurgery for all patients was nine months. Cox congression analysis revealed that total tumor volume, RPA classification and marginal doses were significant prognostic factors, and the number of metastases, ages and center dose were not statistically significant. Conclusion Total tumor volume, RPA classifica- tion and marginal doses were significant prognostic factors. Total tumor volume rather than the number of metastases was the most significant predictor for survival, and should be considered in the choice of appropriate radiosurgery. Linear accelerator radiosurgery alone seems to provide a satisfactory treatment for patients with multiple brain metastases. The necessity of combining WBRT therapy needs further discussion.