摘要目的 探讨磁共振扩散加权成像(DWI)联合血清肿瘤标志物在小细胞肺癌(SCLC)脑转移瘤诊断及疗效评估中的应用价值.方法 回顾性分析2009年2月至2012年2月山西省肿瘤医院368例经组织病理学或细胞学确诊的SCLC患者的病例资料,所有患者均行血清胃泌素释放肽前体(ProGRP)、神经元特异性烯醇化酶(NSE)检测及颅脑DWI,并测量脑转移瘤的DWI序列表观扩散系数(ADC).采用x 2检验比较脑转移组与未脑转移组ProGRP、NSE阳性率的差异,分析ProGRP、NSE、DWI及联合检测对脑转移瘤的诊断效能;采用Kruskal-Wallis H检验比较脑转移患者全脑放疗前后ADC值、ProGRP及NSE水平的变化;采用Pearson相关分析法评价脑转移瘤患者治疗前后ADC值与ProGRP、NSE水平的相关性.结果 169例SCLC脑转移组ProGRP的中位值为2664.7 pg/ml(98.4 ～4 876.8 pg/ml),阳性率为98.2％(166/169);NSE的中位值为41.9 μg/L(9.4～264.3μg/L),阳性率为70.4％(119/169).199例SCLC未脑转移组ProGRP的中位值为514.3 pg/ml(3.9～2 899.3 pg/ml),阳性率为89.4％(178/199);NSE的中位值为40.4 μg/L(0.3～ 176.1 μg/L),阳陛率为64.8％(129/199).两组ProGRP水平差异有统计学意义(u=121.47,P＜ 0.001),而NSE水平差异无统计学意义(u=1.35,P=0.12).ProGRP、NSE、DWI、ProGRP+DWI、NSE+DWI在68例SCLC可疑脑转移病例中的诊断灵敏度分别为80.4％、41.2％、66.7％、92.2％、82.4％,特异度分别为52.9％、35.3％、76.5％、94.1％、88.2％.ProGRP+DWI和NSE+DWI检测的灵敏度和特异度均高于单项检测,差异均有统计学意义(均P＜0.001).156例SCLC脑转移患者行全脑放疗,Pearson相关分析显示,ADC值与ProGRP、NSE水平均呈负相关(r=-0.945,P＜ 0.001;r=-0.995,P＜ 0.001).结论 DWI联合ProGRP及NSE检测可以为SCLC脑转移瘤诊断及全脑放疗效果评估提供客观依据和临床指导.

abstractsObjective To investigate the value of magnetic resonance diffusion-weighted imaging (DWI) in combination with peripheral serum tumor markers in the diagnosis and therapeutic evaluation of small cell lung cancer (SCLC) brain metastases.Methods Retrospective analysis of 368 SCLC cases diagnosed by histopathology or cytology from February 2009 to February 2012 in Shanxi Provincial Cancer Hospital was made.All patients underwent pathological examination of progastrin-releasing peptide (ProGRP),neuron-specific enolase (NSE) and brain DWI,and measured the apparent diffusion coefficient (ADC) of DWI sequences of brain metastases.The difference between the positive rates of ProGRP and NSE in patients with or without brain metastases was compared by the X2 test,and the diagnostic efficiency of ProGRP,NSE,DWI and combined detection for brain metastases were analyzed.The Kruskal-Wallis H test was used to compare the changes of ADC value,ProGRP and NSE before and after brain irradiation therapy in brain metastases of SCLC.Pearson correlation analysis was made to evaluate the correlation between the changes of ADC value and the levels of ProGRP and NSE in SCLC patients with brain metastases before and after treatment.Results The median expression of serum ProGRP in 169 SCLC patients was 2 664.7 pg/ml (98.4-4 876.8 pg/ml),with a positive rate of 98.2 ％ (166/169).The median expression of NSE was 41.9 μg/L (9.4-264.3 μg/L),with a positive rate of 70.4 ％ (119/169).The median expression of serum ProGRP level was 514.3 pg/ml (3.9-2 899.3 pg/ml) in 199 SCLC patients without brain metastasis,the positive rate was 89.4 ％ (178/199).The median expression of NSE was 40.4 μg/L (0.3-176.1 μ,g/L),with a positive rate of 64.8 ％ (129/199).The difference of ProGRP level between the two groups was statistically significant (u =121.47,P ＜ 0.001),but there was no significant difference in NSE level (u =1.35,P =0.12).The sensitivities of ProGRP,NSE,DWI,ProGRP+DWI and NSE+DWI were 68.4 ％,41.2 ％,66.7 ％,92.2 ％,and 82.4 ％,and the specificities were 52.9 ％,35.3 ％,76.5 ％,94.1％,and 88.2 ％.The sensitivity and specificity of ProGRP+DWI and NSE+DWI were higher than those of single test,and the differences were statistically significant (all P ＜ 0.001).One hundred and fifty-six SCLC patients with brain metastases were treated with whole brain radiotherapy.Pearson correlation analysis showed that ADC values were negatively correlated with ProGRP and NSE levels (r =-0.945,P ＜ 0.001;r =-0.995,P ＜ 0.001).Conclusion DWI combined with ProGRP and NSE can provide objective evidence and clinical guidance for the diagnosis of SCLC brain metastases and the evaluation of whole brain radiotherapy.