多层螺旋CT首过期灌注成像和肿瘤微血管密度在评价周围型肺癌TNM分期的临床价值

Clinical Value of 16 Slice Spiral CT Perfusion Enhancement Parameters and Histological Microvessel Density in TNM Staging of Peripheral Non-small Cell lung Cancer

目的探讨多层螺旋CT首过期灌注强化指标和肿瘤微血管密度（MVD）在肺癌TNM分期的临床价值。资料与方法对32例周围型肺癌患者行CT灌注扫描,依据首过期肿块强化的时间-密度曲线（TDC）计算肿瘤的灌注强化指标,按病理结果分为：≤3 cm肺癌组和〉3 cm、≤7 cm肺癌组,累及胸膜组和未累及胸膜组;有淋巴结转移组和无淋巴结转移组;TNM分期按Ⅰ~Ⅱ期和Ⅲ~Ⅳ期分两组,并对肿瘤MVD计数。各组观察指标的差异采用t检验或t’检验;将CT灌注强化指标分别与MVD做相关性分析;利用受试者工作特征（ROC）曲线分析MVD和CT灌注强化指标评价肺癌TNM分期的诊断效能。结果 （1）肿块的强化峰值（PH）、肿块与主动脉PH之比（M/A）、灌注值（PV）和MVD在肿块直径≤3 cm与〉3 cm、≤7 cm之间[分别为（33.73±20.56）HU、（31.26±13.22）HU;（0.28±0.10）、（0.24±0.14）;（1.58±0.83）ml.min-1.ml-1、（1.45±0.81）ml.min-1.ml-1;（73.00±15.03）个/0.74 mm2、（66.42±12.93）个/0.74 mm2]差异均无统计学意义（P〉0.05）。（2）累及胸膜组的PV和MVD均高于未累及胸膜组[分别为（1.83±0.90）ml.min-1.ml-1、（1.15±0.56）ml.min-1.ml-1;（73.40±10.70）个/0.74 mm2、（62.59±13.65）个/0.74 mm2],差异均有统计学意义（P〈0.05）。PH和M/A在累及胸膜组与未累及胸膜组之间[分别为（38.27±15.09）HU、（25.94±11.49）HU;（0.27±0.15）、（0.19±0.11）]差异均无统计学意义（均P〉0.05）。（3）肺癌淋巴结转移组的肿块PH、M/A、PV和MVD均高于无淋巴结转移组[分别为（38.76±14.32）HU、（21.44±6.48）HU;（0.28±0.14）、（0.14±0.07）;（1.73±0.89）ml.min-1.ml-1、（1.10±0.47）ml.min-1.ml-1;（72.58±10.49）个/0.74 mm2、（60.46±14.15）个/0.74 mm2],差异均有统计学意义（P〈0.05）。（4）肺癌Ⅲ~Ⅳ期组PH、M/A、PV和MVD均高于肺癌Ⅰ~Ⅱ期组[分别为（38.61±15.01）HU、（25.65±11.12）HU;（0.30±0.14）、（0.16±0.09）;（1.86±0.94）ml.min-1.ml-1、（1.13±0.46）ml.min-1.ml-1;（75.00±8.76）个/0.74 mm2、（61.18±13.51）个/0.74 mm2],差异均有统计学意义（P〈0.05）。（5）PH、M/A、PV均与MVD呈正相关,其中PV与MVD的相关系数最高（r=0.703,P〈0.01）。（6）利用ROC曲线分析,MVD、PV判断肺癌TNM分期有诊断价值[曲线下面积（AZ）分别为0.812和0.729,P〉0.05];当以MVD〉71.5个/0.74 mm2或PV〉1.16 ml.min-1.ml-1作为判断肺癌TNM分期的诊断阈值时,其敏感性、特异性、诊断符合率分别为86.7%、76.5%、81.13%和73.3%、52.9%、62.5%。结论肺癌CT灌注强化指标PV和MVD与肺癌TNM分期存在一定相关性,通过确定PV及MVD的临界值有助于肺癌TNM分期的量化诊断。

Objective To investigate the value of 16 slice spiral CT perfusion（CTP） enhancement parameters and histological microvessel density（MVD）in TNM staging of peripheral non-small cell lung cancer.Materials and Meth-ods Thirty two patients with pathology proved peripheral non small cell lung cancer underwent CT perfusion scan before operation.The enhance index of CT perfusion were calculated based on the time-density curves（TDC） of fist pass phase.All cases were classified into several groups：diameter ≤3 cm and diameter of 3-7 cm group,pleural invasion and no pleural invasion group,mediastinum lymphatic involvement and without mediastinum lymphatic involvement group,TNM staging of Ⅰ-Ⅱ and Ⅲ-Ⅳ group.The correlations were analyzed between the enhance index of CT perfusion with MVD.Two sample t or t＇ test was used for the statistics.The ROC curve was used to estimate the efficiency of the enhance index of CT perfusion and MVD in TNM staging of lung cancer.Results（1）CTP enhance index（PH,M/A,PV） and MVD between small（diameter of ≤3 cm） and big（diameter of 3-7 cm） tumor had no significant difference（P0.05）.（2） PV and MVD were higher in tumors invloved pleura than without pleural invasion group（P0.05）.（3） Tumors with mediastinum lymphatic involvement had significantly higher value of The CTP enhance index（PV、PH、M/A）and MVD than those without medistinum lymphatic involvement（P0.01）.（4） Tumors of Ⅲ-Ⅳ staging had higher value of CTP enhance index（PH,M/A,PV） and MVD than those in Ⅰ-Ⅱstaging（P0.05）.（5） The CTP enhance index（PH,M/A,PV） of lung cancer correlated positively with the MVD respectively.The highest correlation coefficient was between PV and MVD（r=0.703,P0.01）.（6）With ROC curve analysis,MVD and PV had high value in estimate and predict TNM staging of peripheral non small cell lung cancer.If MVD of 71.5/0.74 mm2 was taken as the threshold in TNM staging,the sensitivity,specificity,accuracy was 86.7%,76.5%,81.13%.If PV of 1.16 ml·min-1·ml-1 was taken as the threshold in predicting TNM staging,the sensitivity,specificity,accuracy was 73.3%,52.9%,62.5%.Conclu-sion The enhance index of CT perfusion PV and histological MVD had correlation with TNM staging of peripheral non small cell lung cancer,which will attribute to evaluate TNM staging of lung cancer.