分次伽马刀治疗大体积脑转移瘤的疗效及预后分析

Analysis of curative effect and prognosis of fractionated Gamma knife in the treatment of large brain metastases

目的探讨分次伽马刀治疗大体积(直径≥3 cm)脑转移瘤的疗效和不良反应,并分析其预后因素。方法选取使用伽马刀治疗的大体积脑转移患者46例,肿瘤体积范围14.1~50.9 cm^3,中位体积24 cm^3。用50%等剂量曲线包括靶区,剂量为4.5~6 Gy/次,共照射5~8次,每周照射5次。生存期采用Kaplan-Meier分析,组间生存率对比采用Log-rank检验,多变量分析采用COX回归模型。结果治疗后临床症状改善率为81.1%(30/37),有效率为80.4%(37/46),局部控制率为89.1%(41/46)。1年和2年总生存率分别为45.6%和21.7%,中位生存期11个月。多因素分析结果显示KPS评分低、原发灶未控和颅外转移是预后不良因素(P<0.05)。结论分次伽马刀治疗大体积脑转移瘤效果确切,不良反应轻。KPS评分低、原发灶未控和颅外转移是预后不良因素。

Objective To evaluate the efficacy and adverse reactions of fractionated Gamma knife in the treatment of large brain metastases（ diameter≥3 cm）,and to analyze its prognostic factors. Methods 46 cases of large brain metastases treated with Gamma knife were selected.Tumor volume ranged from 14.1 to 50.9 cm^3,with a median volume of 24 cm^3. 50%isodose curve was used to include target area with dose of 4.5 to 6 Gy/time,and total irradiation was 5 to 8 times,5 times a week.Survival time was analyzed by Kaplan-Meier analysis,survival rates between groups were compared by Log-rank test,and multivariate analysis by COX regression model.Results After treatment,the improvement rate of clinical symptoms was81.1%（ 30/37）,effective rate was 80.4%（ 37/46）,and local control rate was 89.1%（ 41/46）.The total survival rate of 1 and2 years was 45.6% and 21.7%,respectively,and median survival period was 11 months.Multivariate analysis showed that low KPS score,uncontrolled primary focus and extracranial metastasis were factors of poor prognosis（ P〈0. 05）. Conclusion Fractionated Gamma knife is effective in the treatment of large brain metastases with mild adverse reactions.Low KPS score,uncontrolled primary focus and extracranial metastasis are factors of poor prognosis.