Objective To evaluate the clinical value of CT perfusion (CTP) imaging for providing quantitative information about angiogenesis in patients with lung carcinoma and investigate the correlation of CTP enhancement parameters and histological microvessel density (MVD) with lymphatic involvement in peripheral lung carcinoma. MethodsFifty-three patients with pathology-proved peripheral lung carcinoma underwent CT perfusion scan before operation. The enhancement parameters of CTP were calculated based on the time-density curves (TDC) of fist pass phase. All cases were classified into two groups according to pathologic results: tumor with and without lymph node involvement. Two-sample t test was used for the statistics. The ROC curve was used to assess the efficiency of the enhancement parameters of CT perfusion and MVD for predicting lymphatic involvement.Results Tumors with lymph node involvement had significantly higher value of MVD than those without lymph node involvement (64.69±16.34 and 42.67± 16.78, respectively,t=4.84,P<0.01). Tumors with lymph node involvement had significantly higher value of CTP enhancement parameters (PH, M/A, PV) than those without lymph node involvement [PH= (41.79±15.50) and (29.99±10.91) HU,M/A =0.24±0.09 and 0.15±0.06, PV=(2.14±1.09) and (1.27±0.53) ml·min~(-1)·ml~(-1), t=3.21,3.95, 3.66, P<0.01, respectively]. The CTP enhancement parameters (PH, M/A, PV) of lung cancer correlated positively with the MVD, the highest correlation coefficient was between the PV and MVD (r=0.716, P<0.01). MVD and PV had higher values for predicting lymph node involvement in ROC curve analysis.The sensitivity, specificity and accuracy for predicting lymph node involvement were 80.8%, 81.5% and 81.1% or 84.6% ,85.2% and 84.9% respectively if MVD>52/0.74 mm~2 or PV>1.52 ml·min~(-1)·ml~(-1). ConclusionThe CT perfusion PV and histological MVD have good correlation with lymph node involvement in peripheral lung carcinoma and are important predicting parameters before operation.