局限期SCLC预防性脑照射后脑转移的危险因素分析

目的 评价预防性脑照射后高危脑转移因素，为个体化治疗提供依据。方法 回顾分析2005—2010年间本院诊治的接受PCI的局限期SCLC患者188例。Kaplan-Meier法计算累计脑转移率，采用Logrank法单因素分析和Cox模型多因素分析与累计脑转移发生可能的因素。结果 188例患者中31例出现脑转移(16.5%)，其中1、2、3年累计脑转移发生率分别为4%、15%、20%。单因素分析显示治疗前Ⅲ期、肿瘤标记物升高、化放疗后未达CR、局部区域复发患者具有较高的脑转移率(P=0.044、0.037、0.005、0.007)，多因素分析显示化放疗结束时未达CR、化放疗后局部区域复发患者PCI后脑转移率高(P=0.003、0.040)。结论 化放疗后未达CR或化放疗后局部区域复发者PCI后具有较高的脑转移率。对这部分患者密切的中枢神经系统随访加挽救性脑放疗可能是较好的替代PCI的方法。

An analysis of risk factors for brain metastases after prophylactic cranial irradiation for limited-stage small-cell lung cancer

Objective To evaluate the high-risk factors for brain metastases after prophylactic cranial irradiation (PCI), and to provide a basis for personalized treatment.Methods A retrospective analysis was performed in 188 patients with limited-stage small-cell lung cancer who received PCI in our hospital from 2005 to 2010. The Kaplan-Meier method was used to calculate the cumulative rate of brain metastases. The log-rank test and the Cox model were used for the univariate and multivariate analyses of the potential factors for the cumulative incidence of brain metastases, respectively.Results In the 188 patients, 31(16.5%) had brain metastases. The 1-, 2-, and 3-year cumulative incidence rates of brain metastases were 4%, 15%, and 20%, respectively. The univariate analysis showed that staged Ⅲ disease before treatment, elevated levels of tumor markers, incomplete remission after chemoradiotherapy, and local-regional relapse were risk factors for high incidence of brain metastases (P=0.044, 0.037, 0.005, 0.007). The multivariate analysis revealed that incomplete remission after chemoradiotherapy and local-regional relapse after chemoradiotherapy were risk factors for high incidence of brain metastases after PCI (P=0.003, 0.040).Conclusions Patients with incomplete remission or local-regional relapse after chemoradiotherapy have high incidence of brain metastases after PCI. For those patients, a frequent follow-up of the central nervous system plus salvage cranial irradiation might provide an alternative to PCI.