Dynamic contrast-enhanced magnetic resonance imaging for characterising nasopharyngeal carcinoma: comparison of semiquantitative and quantitative parameters and correlation with tumour stage

To evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for characterising nasopharyngeal carcinoma (NPC). Forty-five newly diagnosed NPC patients were recruited. The initial enhancement rate (E (R) ), contrast transfer rate (k (ep) ), elimination rate (k (el) ), maximal enhancement (MaxEn) and initial area under the curve (iAUC) were calculated from semiquantitative analysis. The K (trans) (volume transfer constant), v (e) (volume fraction) and k (ep) were calculated from quantitative analysis. Student's t-test was used to evaluate the differences among tumour stages. Pearson's correlation between the two sets of k (ep) was performed. Comparing tumours of T1/2 stage (n = 18) and T3/4 stage (n = 27), MaxEn (P = 0.030) and iAUC (P = 0.039) were both significantly different; however, the iAUC was the only independent variable with 69.6 % sensitivity and 76.5 % specificity respectively; v (e) was also significantly different (P = 0.010) with 69.6 % sensitivity and 70.6 % specificity respectively. No significant difference was found among N stages. The two sets of k (ep) s were highly correlated (r = 0.809, P < 0.001). Forty-three patients had chemoradiation, one palliative chemotherapy and one radiotherapy only. In the four patients with poor outcome, k (el,) E (R,) MaxEn and iAUC tended to be higher. Neovasculature in higher T stage NPC exhibits some parameters of increased permeability and perfusion. Thus, DCE-MRI may be helpful as an adjunctive technique in evaluating NPC. aEuro cent The correct assessment of nasopharyngeal carcinoma (NPC) is important for planning treatment. aEuro cent Neovasculature in higher T stage NPC exhibits increased permeability and perfusion. aEuro cent Correlation between quantitative and semi-quantitative analysis validates the robustness of DCE-MRI. aEuro cent DCE-MRI may be helpful as an adjunctive parameter in evaluating NPC.