Patlak联合不可逆两组织隔室模型动态^(18)F-FDG PET/CT诊断肺原发肿瘤胸部高代谢转移性淋巴结

Patlak combined with irreversible two-tissue compartment model dynamic^(18)F-FDG PET/CT for diagnosis of hypermetabolic thoracic metastatic lymph nodes of primary lung tumor

目的观察Patlak联合不可逆两组织隔室模型(2TC-3k)动态^(18)F-FDG PET/CT诊断肺原发肿瘤胸部高代谢转移性淋巴结的价值。方法前瞻性纳入16例CT显示胸部存在可疑淋巴结转移且拟接受PET/CT检查的肺原发肿瘤患者,行胸部动态和全身静态^(18)F-FDG PET/CT扫描;计算全身静态PET/CT图像中原发肿瘤及胸部高代谢淋巴结的最大标准摄取值(SUV_(max))及平均标准摄取值(SUV_(mean)),纳入淋巴结SUV_(max)>2.5者。采用Patlak图形分析和2TC-3k分析原发肿瘤和高代谢淋巴结动态数据,获取动力学参数的一阶特征参数,建立logistic模型;以病理学为金标准,分析模型诊断胸部高代谢淋巴结转移的效能。结果共纳入11例患者、32枚胸部高代谢淋巴结,病理学示15枚为转移性、17枚非转移性。Ki_Kurtosis诊断胸部转移性高代谢淋巴结的曲线下面积(AUC)为0.81,以71590.45为Ki_Kurtosis的截断值,其敏感度为70.60%,特异度为86.70%;V_B_Entropy的AUC为0.79,以6.16×10^(-4)为V_B_Entropy的截断值,其敏感度为80.00%,特异度为82.40%。肺原发肿瘤与胸部高代谢转移性淋巴结V_B_Kurtosis(r=0.67,P<0.05)和Ki_UPP(r=0.69,P<0.05)呈正相关。Patlak动态PET/CT模型诊断胸部转移性高代谢淋巴结的AUC为0.85[95%CI(0.71,0.99)],敏感度为76.50%,特异度为93.30%;2TC-3k动态PET/CT模型的AUC为0.87[95%CI(0.74,0.99)],敏感度为82.40%,特异度为80.00%;二者联合模型的AUC为0.91[95%CI(0.80,1.00)],敏感度为94.10%,特异度为80.00%;3个模型AUC两两比较差异均无统计学意义(P均>0.05)。结论Patlak结合2TC-3k动态^(18)F-FDG PET/CT对诊断肺原发肿瘤胸部高代谢转移性淋巴结具有一定价值。

Objective To observe the value of Patlak combined with irreversible two-tissue compartment model(2TC-3k)dynamic^(18)F-FDG PET/CT for diagnosis of hypermetabolic thoracic metastatic lymph nodes of primary lung tumor.Methods Totally 16 patients with suspected thoracic lymph node metastasis who would undergo PET/CT were prospectively enrolled.Chest dynamic and whole-body static^(18)F-FDG PET/CT scanning were performed.The maximum standard uptake value(SUV_(max))and the mean standard uptake value(SUV_(mean))of primary tumor and hypermetabolic thoracic lymph nodes on whole-body static PET/CT images were calculated,and patients with SUV_(max) of lymph node>2.5 were enrolled.Patlak graphic analysis and 2TC-3k were used to analyze dynamic data of primary tumor and hypermetabolic lymph nodes to obtain the first-order characteristic parameters of each kinetic parameter,and then logistic models were established.Taken pathology as the gold standards,the efficacy of logistic models for diagnosing hypermetabolic thoracic lymph node metastasis were analyzed.Results A total of 11 patients with 32 hypermetabolic thoracic lymph nodes were enrolled.Pathology showed 15 metastatic and 17 non metastatic lymph nodes.The area under the curve(AUC)of Ki_Kurtosis for diagnosing hypermetabolic thoracic metastatic lymph nodes was 0.81.Taken 71590.45 as the cut-off value of Ki_Kurtosis,the sensitivity was 70.60%and the specificity was 86.70%.AUC of V_B_Entropy was 0.79.Taken 6.16×10^(-4) as the cut-off value of V_B_Entropy,the sensitivity was 80.00%and the specificity was 82.40%.Both V_B_Kurtosis(r=0.67,P<0.05)and Ki_UPP(r=0.69,P<0.05)of primary lung tumors were positively correlated with those of hypermetabolic thoracic metastatic lymph nodes.AUC of Patlak dynamic PET/CT model for diagnosing hypermetabolic thoracic metastatic lymph nodes was 0.85[95%CI(0.71,0.99)],with sensitivity of 76.50%and specificity of 93.30%,while of 2TC-3k dynamic PET/CT model was 0.87[95%CI(0.74,0.99)],with sensitivity of 82.40%and specificity of 80.00%.AUC of the combined model of Patlak and 2TC-3k was 0.91[95%CI(0.80,1.00)],the sensitivity and specificity was 94.10%and 80.00%,respectively.There was no significant difference of AUC between each 2 models(all P>0.05).Conclusion Patlak combined with 2TC-3k dynamic^(18)F-FDG PET/CT had a certain value for diagnosis of hypermetabolic thoracic metastatic lymph nodes of primary lung tumor.