Microvessel density of malignant and benign hepatic lesions and MRI evaluation

AIM:To study the difference of microvessel density(MVD)between malignant and benign hepatic lesions and studythe relationship between MVD and dynamic enhancedmagnetic resonance imaging(MRI)for evaluation ofmicrovessels within malignant and benign hepatic lesions.METHODS:A total of 265 specimens of hepatocellularcarcinoma(HCC),122 cirrhosis tissues and 22 hepatic benignlesions were enrolled for MVD by immunohistochemistryon tissue microarray,of which 49 underwent MRIexamination before surgery,then contrast-to-noise ratios(CNR)and enhancement index(EI)in all the phases werecalculated.Pearson correlation was performed for correlationanalysis between CNR,EI and MVD.RESULTS:MVD of HCC was 22.7±15.8(mean±SD),whichwas obviously higher than that of cirrhosis tissue(8.3±7.6,P<0.01),but was not statistically different from that of benignlesions(31.3±22.7,P>0.05).Among HCC,MVD of gradesⅠ-Ⅱ was 29.9±18.6,which was much higher than those ofgrade Ⅲ(22.2±18.2,P<0.01)and gradeⅣ(22.9±19.0,P<0.01).MVD of HCC(P=0.018)and of benign lesions(P=0.014)were both correlative with CNR in arterial phase.CONCLUSION:Neoangiogenesis is an important featurefor malignant tumor,and MVD may act as a biologicalmarker in differentiating malignant from benign hepaticlesions.Dynamic enhanced MRI,especially image in arterialphase,may act as an MVD evaluation criterion for malignantand benign hepatic lesions.