3.0T磁共振肺癌动态增强特征及其与微血管密度的关系

Characteristics of 3.0T Dynamic Contrast-enhanced Magnetic Resonance Imaging of Lung Cancer and Its Correlation with Microvessel Density

目的探讨肺癌在3.0T磁共振(MR)动态增强的特点及其与组织病理学和微血管密度(MVD)的相关性。方法应用3.0TMR对37例经病理证实为肺癌的患者进行胸部动态增强扫描,采用肝脏加速容积采集(LAVA)序列间断扫描至注射造影剂后4min,计算增强扫描各期肿瘤相对强化度(SI%),绘制T-SI%曲线,将曲线形态分为A型(速升-下降型)、B型(速升-平台型);计算强化参数:早期强化峰值(SIEP%)、早期峰值强化时间(TEP)、最大强化峰值(SIpeak%)、最大峰值强化时间(Tpeak)。比较不同大小(≤5cm和>5cm)、部位(中央型和周围型)、组织学类型(鳞癌和腺癌)、分化程度(高、中、低分化)肿瘤间T-SI%曲线形态及强化参数。对10例行手术治疗者切除的组织进行CD31和CD34染色,分析肿瘤强化参数与MVD的相关性。结果肿瘤最大径≤5cm和最大径>5cm者间SIEP%、SIpeak%、Tpeak的差异具有显著性,肿瘤最大径≤5cm者的SIEP%、SIpeak%均高于肿瘤最大径>5cm者(P=0.014,P=0.024)。不同部位、病理类型及分化程度肿瘤间SIEP%、SIpeak%的差异均无显著性(P>0.05)。SIEP%、SIpeak%与MVD呈正相关。结论SIEP%、SIpeak%与肿瘤大小有关。SIEP%、SIpeak%可以反映肿瘤MVD状况。

Objective To explore the characteristics of 3.0T dynamic contrast-enhanced magnetic resonance （DCE-MR） imaging of lung cancer and its correlation with microvessel density （MVD）. Methods Thirty-seven patients with pathologically proven lung cancer underwent DCE-MR with liver acquisition with volume acceleration sequence. DCE-MR images were acquired intermittently for a total of 4 minutes on a 3.0T MR scanner. The relative enhancing percentage （ SI% ） at each time point was measured. The shapes of T-SI% curves were defined as A （ rapidly ascending followed by a descending branch） and B （ rapidly ascending branch followed by a plateau）. The early peak enhancement （SIEp%）, early peak time （TEp）, maximum enhancement （SIpeak%） , and peak time （Tpeak） were recorded and compared according to different dimensions, locations, histological types, and differentiation grades of lung cancer. Tumour specimens were immunostained for CD31 and CD34 in ten patients who had undergone surgical resections. The enhancement values were correlated with MVD. Results The SIEP% and SIpeak% of tumors with smaller dimensions （ ≤5 cm） were significantly higher than those with larger dimensions （ 〉 5 cm） （P = 0. 014, P = 0. 024）. The SIEP% and SIpeak% were positively correlated with the tumor MVD. Conclusion The SIEP% and SIpeak% of lung cancer correlate with tumor dimension and can reflect MVD in tumor.