肿瘤体积和放疗剂量对体部γ刀治疗肝细胞肝癌的预后影响

目的 探索GTV和放疗剂量对体部γ刀治疗肝细胞肝癌的预后影响。 方法 回顾分析2012—2015年间 69例体部γ刀治疗肝细胞肝癌患者临床资料。采用50%或60%等剂量曲线覆盖计划靶区,单次 4~5 Gy,边缘总剂量 36~50 Gy (中位数45 Gy)。观察其近期疗效、总生存期及不良反应。采用ROC曲线确定肿瘤体积最佳界值。采用Kaplan-Meier法计算生存率,Logrank检验和单因素分析,Cox模型多因素分析。 结果 69例患者放疗近期总有效率为67%。1、2年生存率分别为62%、40%,中位生存期18.6个月。多因素分析显示GTV<93 cm³(P=0.013)及放疗近期有效(P=0.000)是影响生存的因素。GTV<93 cm³时患者≥45 Gy亚组预后明显好于<45 Gy亚组(P=0.019),而GTV≥93 cm³组患者中剂量大小对生存期无明显影响(P=0.665)。 结论 肿瘤体积是影响局部晚期肝癌患者生存的独立预后因素。小体积肿瘤行大剂量放疗患者生存获益。对肿瘤体积较大患者不宜强行追求高剂量照射。

Effect of tumor volume and radiation dose on the prognosis of hepatocellular carcinoma patients treated with whole body gamma knife

Objective To examine the effects of gross tumor volume (GTV) and radiation dose on the prognosis of hepatocellular carcinoma (HCC) patients treated with whole body gamma knife.Methods The clinical data of 69 HCC patients who underwent body gamma knife treatment from January 2012 to June 2015 in the Radiotherapy Center of the PLA General Hospital were retrospectively reviewed.Based on a 50% or 60% isodose coverage of the planning target volume (PTV), patients were treated with a radiation dose of 4-5 Gy per fraction, and a total marginal dose of 36-50 Gy (median dose 45 Gy).Short-term efficacy, overall survival (OS), and the adverse effect of the treatment were evaluated.The optimal cut-off tumor volume was identified using the receiver operating characteristic curve, and survival was determined by the Kaplan-Meier method.Univariate and multivariate analyses were performed using the log-rank test and Cox proportional hazards regression model, respectively.Results The overall short-term response rate of the 69 patients was 67%.The 1-and 2-year OS rates were 62% and 40%, respectively, with a median survival of 18.6 months.The multivariate analysis showed that gross tumor volume (GTV)<93 cm3(P=0.013) and short-term efficacy of radiotherapy (P=0.000) were significant independent prognostic factors for survival.When GTV was<93 cm3, prognosis was significantly better in patients treated with a dose of ≥45 Gy than in those with<45 Gy (P=0.019).In contrast, radiation dose had no significant effect on survival among patients with GTV>93 cm3(P=0.665).Conclusions GTV is an independent prognostic factor for overall survival of HCC patients.Although high-dose radiotherapy provides survival benefits to patients with small GTV, it is not necessarily suitable for patients with large GTV.