Lymphatic involvement of pulmonary carcinoma correlated to the enhancement patterns of dynamic contrast-enhanced MRI and histological microvessel density: ROC curve analysis

Objective: To investigate the correlations of lymphatic involvement and perfusion patterns of pulmonary carcinoma derived by dynamic contrast-enhanced MRI as well as the histological microvessel density (MVD)of the tumor's. Methods: Fifty-eight patients with pulmonary carcinoma were classified into two group according to the pathologic reports:tumors with mediastinum lymphatic involvement and tumors without mediastinum lymphatic involvement. All cases were underwent dynamic contrast- enhanced MR scanning. The parameters of dynamic contrast-enhanced MRI were calculated based on time-signal intensity curves. The correlations of lymphatic involvement and MRI parameters as well as tumor's MVD were analyzed. Results: Tumors with mediastinum lymphatic involvement (n=35) had significantly higher values of both MVD and SS than those without mediastinum lymphatic involvement (n=23) (MVD72.37±13.74 vs 42.61±16.18;SS=5.05±1.16 vs 2.57±l.09)(t=7.521;t=8.157,P<0.01). With the ROC curve analysis, if the SS 3.8 or MVD 63 was taken as s a threshold to predict lymphatic involvement, high sensitivity of SS(85.7% ,30 of 35), MVD (74.3%, 26 of 35) and high overall accuracy of SS (87.9, 51 of 58), MVD (82.8%, 48 of 58) could be reached, respectively. The area zone under the ROC curve of SS (AZSS) tended to have higher value than that of MVD (AZMVD) (0.958 versus 0.920), however, the difference between the values of AZSS and AZMVD was not significant (P=0.09). Conclusion: SS and MVD had good correlation with lymphatic involvement of pulmonary carcinoma, and could be used to predict lymphatic involvement. (authors)