ADC直方图鉴别脑转移瘤病理性质的价值

Value of apparent diffusion coefficient histogram to differential diagnosis of common pathological types of brain metastases

目的探讨ADC直方图在腺癌脑转移瘤和鳞癌脑转移瘤鉴别诊断中的价值。方法回顾性分析经病理证实的48例脑转移瘤(腺癌31例,鳞癌17例)术前磁共振弥散加权成像,绘制整个肿瘤的ADC直方图,并计算出最小ADC值(ADCmin)、最大ADC值(ADCmax)、平均ADC值(ADCmean)、第5百分位数(ADC_5th)、第25百分位数(ADC_25th)、中位数(ADC_50th)、第75百分位数(ADC_75th)、第95百分位数(ADC_95th)。结果腺癌脑转移瘤ADCmin、ADCmean、ADCmax均明显高于鳞癌脑转移瘤(P<0.05),但是两种性质脑转移瘤ADC_5th、ADC_25th、ADC_50th、ADC_75th、ADC_95th均未见显著性差异(P>0.05)。根据ROC曲线分析结果,以ADCmin=0.600×10^(-3)mm^2/s为阈值鉴别腺癌脑转移瘤和鳞癌脑转移瘤时,诊断效能最佳,ROC曲线下面积最大,为0.700,诊断灵敏度为64.7%,特异度为74.2%。结论 ADC直方图可以提供肿瘤的整体信息,有助于鉴别诊断腺癌脑转移瘤与鳞癌脑转移瘤。

Objective To investigate value of apparent diffusion coefficient(ADC)histograms to the differentialting of squamous carcinoma brain metastases from adenocarcinoma brain metastases.Methods Retrospective analysis of preoperative diffusion weighted imaging data of 48 patients with brain metastases confirmed by pathology was made.The ADC histogram of the entire tumor of every brain metastasis was drawn.The percentage of ADC values,the minimal ADC(ADCmin),mean ADC(ADCmean),maximal DC(ADCmax),skewness and kurtosis were statistically compared between the adenocarcinoma brain metastases and squamous carcinoma brain metastasis.Results There were significant differences in ADCmin,ADCmean,and ADCmax between two groups of brain metastases(P<0.05).The area under the receiver operating characteristic curve of squamous carcinoma and adenocarcinoma brain metastases was maximal when the value of ADCmin cutoff was 0.60×10-3 mm2/s.The specificity and the sensitivity to distinguishing the squamous carcinoma brain metastasis from the adenocarcinoma brain metastasis was 72.4%and 64.7%respectively.Conclusions ADC histogram can provide the overall information of brain metastasis tumor and is helpful to differential diagnosis of squamous carcinoma brain metastases from adenocarcinoma brain metastasis.