Role of dynamic contrast-enhanced MRI in distinguishing pseudoprogression from true progression of glioma

Objective To evaluate the value of 3-T dynamic contrast-enhanced MRI(DCE-MRI)in distinguishing pseudoprogression(PP)from true progression(TP)of glioma. Methods DCE-MRI examination were performed in 32 cases of glioma to distinguish pseudoprogression fromtrue progression.The values of volume transfer constant(K^trans),volume fraction of extravascular extracellular space(v_e),reflux constant(k_ep)and fractional plasma volume(v_p)were calculated in the newly developed abnormal enhancement by pharmacokinetic model.Mann-Whitney U test was used to calculate the statistical significance between TP group and PP group.Receiver operating characteristic(ROC)curve was performed for evaluation of the sensitivity,specificity and AUC. Results TP group(n=18)showed higher K^trans(0.34 min^-1 vs. 0.17 min^-1)and higher v_e(0.53 vs. 0.39) when compared with the PP group(n=14),the differences were statistically significant(Z=3.02,P＜0.01;Z=2.03,P＜0.05).However,the differences in kep and ve were not statistically significant(P＞0.05).ROC curve showed the AUC value to diagnose TP and PP of K^trans was the highest(0.815),and the sensitivity and specificity were 72.2% and 85.7%. Conclusion The permeability parameters on DCE-MRI is useful in distinguishing pseudoprogression from glioma true progression,and to be a guidance for clinical treatment.