不同表观扩散系数对前列腺癌盆腔转移性淋巴结的定性诊断价值

目的探讨不同表观扩散系数(ADC)对前列腺癌盆腔转移性淋巴结的定性诊断价值。方法收集58例前列腺癌伴盆腔淋巴结肿大患者的临床及磁共振资料;盆腔肿大淋巴结ADC值的获取分别采用局部测量法(partial measurement)与整体测量法(overall measurement);采用Bland-Altman法进行一致性分析,并以受试者工作曲线(ROC)比较两种ADC值的诊断效能。结果 58例前列腺癌患者共计69枚肿大淋巴结进行入组研究,经病理证实后,其中炎性淋巴结22枚、转移性淋巴结47枚。Bland-Altman结果显示:局部测量法(ADC_partial)与整体测量法(ADC_overall)获取的ADC值存在8.7%(6/69)在95%一致性界限(95%limits of agreement, 95%LoA)之外,说明其一致性较差,提示ADC_partial与ADC_overall是淋巴结ADC值的两种不同测量方法,不能相互替代。ROC曲线结果显示:ADC_partial对前列腺癌盆腔转移性淋巴结的敏感度、特异性以及曲线下面积分别为82.98%、90.91%以及0.927;ADC_overall对前列腺癌盆腔转移性淋巴结的敏感度、特异性以及曲线下面积分别为89.36%、95.45%以及0.962;ADC_overall的诊断效能优于ADC_partial(Z=2.013, P=0.044)。结论 ADC_partial与ADC_overall均对前列腺癌盆腔转移性淋巴结的定性诊断有着较大的优势,ADC_overall的诊断效能更高。

Qualitative Diagnostic Value of Different Apparent Diffusion Coefficients on Metastatic Pelvic Lymph Nodes in Prostate Cancer

Objective To evaluate the diagnostic value of different apparent diffusion coefficients (ADC) on metastatic pelvic lymph nodes in prostate cancer. Methods We collected the clinical and MRI data of 58 prostate cancer patients with pelvic lymphadenectasis. The ADC values of enlarged pelvic lymph nodes were obtained by partial measurement (ADC_partial) and overall measurement (ADC_overall), and the consistency was analyzed by Bland-Altman method. The diagnostic efficacy of the two ADC values was compared by the Receiver operating curve (ROC). Results A total of 69 enlarged lymph nodes were involved, including 22 inflammatory lymph nodes and 47 metastatic lymph nodes. Bland-Altman results showed that 8.7% (6/69) of ADC values obtained by ADC_partial and ADC_overall were beyond the 95% limit of agreement (95% LoA), indicating poor consistency and suggesting that ADC_partial and ADC_overall were two different methods for measuring ADC values of lymph nodes and could not be replaced by each other. ROC curves showed that the sensitivity, specificity, the area under the curve of ADC_partial and ADCoverall were 82.98%, 90.91%, 0.927 and 89.36%, 95.45%, 0.962, respectively. The diagnostic efficacy of ADCoverall was better than that of ADC_partial (Z=2.013, P=0.044). Conclusion Both ADC_partial and ADC_overall have great advantages in the qualitative diagnosis of metastatic pelvic lymph nodes in prostate cancer, and ADCoverall has higher diagnostic efficiency.