The use of CT perfusion to determine microvessel density in lung cancer: Comparison with FDG-PET and pathology

Objective To investigate the validity of CT perfusion in assessing angiogenic activity of lung cancer. Methods Fifty-six patients with lung cancer scheduled for elective surgical resection received 16-slice helical CT perfusion imaging. Time-density curve (TDC), blood flow (BF), blood volume (BV), mean transmit time (MTT) and permeability surface area product (PS) were calculated. 18F-deoxyglucose-positron emission tomography (FGD-PET) was carried out in 14 out of the 56 patients to calculate standardized uptake values (SUVs). Tumor microvessel density (MVD) was examined using CD34 immunohistochemical staining of the resected tumor tissue. Pearson’s correlation analysis was used to evaluate potential correlation between CT perfusion parameters and MVD or SUV. Results Average time to peak height (TPH) of the TDCs (including two types of TDC) was 24.38±5.69 seconds. Average BF, BV, MTT and PS were 93.42±53.45 ml/100g/min, 93.42±53.45 ml/100g, 6.83±4.51 s and 31.92±18.73 ml/100g/min, respectively. Average MVD was 62.04±29.06/HPF. The mean SUV was 6.33±3.26. BF was positively correlated with MVD (r=0.620, P <0.01) and SUV (r=0.891, P <0.01). PS was also positively correlated with SUV (r=0.720, P <0.05). A positive correlation was also observed between tumor MVD and SUV (r=0.915, P <0.01). Conclusions CT perfusion imaging is a reliable tool to evaluate the tumor neovascularity of lung cancer.