单发或多发脑转移瘤的放疗疗效研究

Radiotherapy curative effects for single or multiple brain metastases

目的探求单发与多发脑转移瘤的合理放疗方案。方法回顾性分析2005年7月至2008年7月收治的50例单发或多发脑转移瘤患者的资料。所有患者原发灶均得到控制，30例（联合组）采用全脑放疗＋立体定向放射外科治疗，20例（单一组）采用单纯立体定向放射外科治疗。立体定向放射外科治疗处方剂量均采用45％-75％等剂量线包绕计划靶区，边缘剂量15—20Gy，中心剂量30-45Gy，一次完成；全脑放疗每次分割剂量为2Gy，1次／d，5次／周，总剂量40Gy／4周。结果联合组有效率为90．0％（27／30），单一组为60．0％（12／20），联合组的有效率明显高于单一组（r=6．294，P=0．012）；联合组和单一组的1年生存率分别为50．0％（15／30）和35．0％（7／20），2年生存率分别为30．0％（9／30）和15．0％（3／20），两组1、2年生存率差异均无统计学意义（χ^2=1．096，P=0．295；χ^2=1．480，P=0．224），两组均无生存3年以上的患者；分层分析显示，在单发病灶患者中，两组1年生存率差异无统计学意义（100．0％：66．7％，χ^2=1．556，P：0．212），在多发病灶患者中，联合组的1年生存率明显优于单一组（42．3％：29．4％，χ^2=11．023，P=0．001），在单发和多发病灶患者中，两组2年生存率差异均无统计学意义（75．0％：66．7％，χ^2=1．200，P=0．273；23．1％：5．9％，χ^2=3．782，P=0．052）。结论全脑放疗和立体定向放射外科是治疗单发或多发脑转移瘤的重要手段，对于单发脑转移瘤可单独行立体定向放射外科治疗，多发脑转移瘤则应行全脑放疗联合立体定向放射外科治疗。

Objective To investigate the better radiation modalities for single and multiple brain metastases. Methods Between July 2005 and July 2008, 50 patients with single or multiple brain metastases were retrospectively analyzed. The primary cancer of all patients were controlled. Thirty patients with whole brain radiotherapy and stereotactic radiosurgery were included in the combination group, and 20 patients with stereotactic radiosurgery were included in another group. Stereotactic radiosurgery prescription doses of 45% - 75% isedose line were used to wrap around the planning target, which was 15-20 Gy in edge and 30-45 Gy in center. Stereotactic radiosurgery was performed once. Whole brain radiotherapy total dose was 40 Gy, which was given to patients by 2 Gy in 1 fraction, 1 fraction every day, 5 times every week. Results The efficient rate of combination group was 90% （27/30）, and single group was 60% （12/20）. It was obviously higher in combination group （χ^2 = 6. 294, P = 0. 012）. For combination group, the 1-year survival rate was 50% （15/30） and the 2-year survival rate was 30% （9/30）. However, for another group, the 1-year survival rate was 35% （7/20） and the 2-year survival rate was 15% （3/20）. The survival rates of two groups were no difference （χ^2 = 1. 096, P = 0. 295 ;χ^2= 1. 480, P = 0. 224）. There were no patients survived more than 3 years in both groups. Stratified analyses showed that the 1-year survival rates of the patients with single brain metastasis were no difference in two groups （ 100.0% vs 66.7%, χ^2 = 1. 556, P = 0.212）. Whereas the 1-year survival rate in combination group of the patients with multiple brain metastases was higher than that in single group （42.3% vs 29.4%, χ^2= 11. 023, P =0.001）. There were no statistically significant differences in 2-year survival rates in both groups with single and multiple brain metastases （75.0% vs 66.7%, χ^2 = 1. 200,P=0.273; 23.1% vs 5.9% ,χ^2=3.782,P=0.052）. Conclusion Whole brain radiotherapy and stereotactic radiosurgery are important treatment modalities for single or multiple brain metastases. The optimal treatment modality for single brain metastasis is stereotaetie radiosurgery, while it is a good choice to make whole brain radiotherapy and stereotaetic radiosurgery for multiple brain metastases.