目的:探讨现代综合治疗模式及诊断技术下，局限期小细胞肺癌(SCLC)放化疗有效者行脑预防照射(PCI)的疗效及复发失败模式。方法:回顾性分析2006—2014年间共201例于中国医学科学院肿瘤医院接受放化疗综合治疗且达有效[完全缓解(CR)/部分缓解(PR)]的局限期SCLC患者的临床资料。综合治疗采用以调强放疗和≥4周期EP/CE方案化疗为主的同步或序贯放化疗，采用脑MRI(90.0%)或CT(10.0%)重新评估有无脑转移。比较PCI组(91例)及非PCI组(110例)的长期生存及复发失败类型。结果:全组患者中位随访时间77.3个月(95%n CI为73.0～81.5个月)。PCI组中位总生存(OS)为58.5个月，2、5年OS分别为72.5%、47.7%；非PCI组中位OS为34.5个月，2、5年OS分别为61.7%、35.8%(n P＝0.075)。PCI组中位无进展生存(PFS)期为22.0个月，2、5年PFS分别为48.0%、43.4%；非PCI组中位PFS为13.9个月，2、5年PFS分别为34.4%、26.7%(n P＝0.002)。PCI组2、5年累积脑转移率为6.6%与12.2%，非PCI组为30.0%与31.0%(n P＝0.001)；初发脑转移率分别为4.4%与25.5%，中位初发脑转移时间分别为11.9个月与8.7个月(n P<0.001)。多因素分析显示综合治疗后疗效评价(n P<0.001)、PCI(n P＝0.033)是PFS的独立预后因素。分层分析表明综合治疗后达CR患者行PCI显著提高5年PFS(72.7%∶48.0%，n P＝0.013)，疗效达PR者行PCI未提高5年PFS(26.1%∶20.2%，n P＝0.213)。n 结论:在现代放化疗综合治疗模式下和更准确的脑转移诊断方法下，放化疗有效的局限期SCLC患者行PCI可改善PFS，降低初发脑转移率和全部脑转移率。“,”Objective:To evaluate the clinical efficacy and failure patterns of prophylactic cranial irradiation (PCI) in patients with limited-stage small cell lung cancer (LS-SCLC) on the basis of modern chemoradiotherapy and diagnostic techniques.Methods:In this retrospective study, clinical data of 201 LS-SCLC patients treated with chemotherapy (EP/CE regimens, ≥4 cycles) and intensity-modulated radiotherapy (IMRT) in Cancer Hospital of Chinese Academy of Medical Sciences from 2006 to 2014 were reviewed. All patients were primarily managed with concurrent or sequential chemoradiotherapy and achieved complete response (CR) or partial response (PR). Ninety percent of patients were revaluated for brain metastasis (BM) by MRI and 10% by CT scan. Long-term survival and failure patterns were compared between the PCI (n n=91) and non-PCI groups (n n=110).n Results:The median follow-up time was 77.3 months (95%n CI 73.0-81.5 months). The median overall survival (OS), 2-and 5-year OS rates were 58.5 months, 72.5% and 47.7% in the PCI group, and 34.5 months, 61.7% and 35.8% in the non-PCI group (n P=0.075). The median progression-free survival (PFS), 2-and 5-year PFS rate were 22.0 months, 48.0% and 43.4% in the PCI group, significantly higher than 13.9 months, 34.4% and 26.7% in the non-PCI group (n P=0.002). The 2- and 5-year cumulative incidence of BM were 6.6% and 12.2% in the PCI group, and 30.0% , 31.0% in the non-PCI group (n P=0.001). The median time and rate of BM as an isolated first site of relapse were 11.9 months and 4.4% in the PCI group, and 8.7 months and 25.5% in the non-PCI group (n P<0.001). Multivariate analysis showed that response after chemoradiotherapy (n P<0.001) and PCI (n P=0.033) were the independent prognostic factors for PFS. Stratified analysis demonstrated that PCI significantly improved the 5-year PFS in patients who achieved CR (72.7% n vs. 48.0%, n P=0.013), while it did not improve the 5-year PFS in patients who obtained PR (26.1% n vs. 20.2%, n P=0.213).n Conclusion:In the new era of standard chemoradiotherapy and more accurate diagnostic methods for BM, PCI was associated with improved PFS and lower incidence of BM in LS-SCLC patients.