Clinical Research Of 320-Slice CT Dual-input Volume Perfusion Imaging In Diagnosing Primary Lung Cancer

Lung blood is supplied by double circulation(pulmonary circulation and systemic circulation), the pulmonary circulation accounting for most part of the blood supply in normal physiological condition. For primary lung cancer, the composition proportion of its blood supply is different from normal lung tissue and pulmonary benign lesions. The whole tumor perfusion information of lung could be gotten by 320-slice CT perfusion(CTp) imaging. Through Dual-input CT perfusion(DICTp) mode could distinguish two circulating blood supply of lesions, and get the blood flow information of tumors: pulmonary flow(PF), bronchial flow(BF) and perfusion index [PI = PF /(PF + BF)]. Using post-processing workstation to analysis the Dual-input perfusion data of pulmunary tumor-like lesions(n=150), which were gotten by 320-slice CT perfusion scan. 28 cases of benign lesions including inflammatory pseudotumor(n=4), tuberculosis(n=21) and pulmonary hamartoma ball(n=3) were confirmed by pathology biopsy or surgical excision. Pathological types of 87 cases of malignant lesions were confirmed, including adenocarcinoma(n=43), squamous cell carcinoma(n=26) and small cell carcinoma(n=18). Differentiation degree of 59 malignant lesions were also confirmed, including well-differentiated carcinoma(n=7), middle-well-differentiated carcinoma(n=7), middle-differentiated carcinoma(n=12), poorly-middle-differentiated carcinoma(n=12) and poorly differentiated carcinoma(n=21). Using independent sample t test to analysis benign and malignant lesion of lung. The results revealed that the differences of PF, BF and PI values between benign and malignant lesion were statistically significant(P<0.05). Then analysising ROC curve: when the PI value is 55.60, the sensitivity(82.1%)and specificity(89.7%) of PI to identify lung cancer was highest. But the sensitivity and specificity of PF and BF was not high, no matter what value they were. LSD pairwise comparisons examined whether there is statistically significant difference in perfusion values between different histological types of lung cancer: The difference of PI between adenocarcinoma and squamous cell carcinomas was statistically significant(p<0.05), no statistical significance of difference of PF and BF. No statistical significance of difference of PF, BF and PI between adenocarcinoma and small cell carcinoma, squamous cell carcinoma and small cell carcinoma. Spearman correlation analysis showed that perfusion value of PI was negatively correlated with the differentiation degree of lung cancer(correlation coefficient-0.495, p<0.05). PF and BF has no correlation with differentiation degree of lung cancer. Thus, we can draw the following conclusions:(1) primary lung cancer was supplied by double blood circulation(pulmonary circulation and systemic circulation), with the dominance of systemic circulation. However, benign pulmonary lesions were predominantly supplied by pulmonary circulation.(2) PI value of dual-input perfusion could provide guidance for differentiating benign and malignant lesion of lung. It would prompt as benign lesion when PI was above 55.60, otherwise suggest malignancy.(3) Comparing primary pulmonary adenocarcinoma and squamous cell carcinoma, squamous cell carcinoma accepted more systemic circulation.(4) With the increase of differentiation degree of primary lung cancer, the proportion of systemic circulation blood supply showed a trend of increase. In summary, the pulmonary dual-input perfusion could provide guidance to differentiate benign and malignant lung lesion. Potential application technology for lung cancer pathology and clinical differentiation was anticipated as dual-input perfusion, which could provide important reference for clinical treatment program.