Prediction of short-term treatment outcome of nasopharyngeal carcinoma based on voxel incoherent motion imaging and arterial spin labeling quantitative parameters

PURPOSE: To evaluate the early response of chemoradiotherapy (CRT) in nasopharyngeal carcinoma (NPC) based on intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and three-dimensional pseudo-continuous arterial spin labeling (3D pCASL). MATERIALS AND METHODS: Forty patients diagnosed with NPC were recruited and divided into complete remission (CR) and partial remission (PR) group after CRT. All patients underwent IVIM and ASL and the related parameters was obtained. These parameters include pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), average blood flow ( BF(avg)), minimum blood flow (BF(min)), and maximum blood flow (BF(max)). Student’s t test was used to compare the difference in ASL and IVIM derived parameters between CR and PR. The Areas under curve (AUC) of the receiver operating characteristic (ROC) was used to analyze the diagnostic performance of each parameter of ASL and IVIM to the treatment outcome. RESULTS: the D value of IVIM in CR group was lower than that of the PR group ( P = 0.014),. Among the parameters of ASL, the BF(avg) and BF(max) of the CR group were higher than those of the PR group(p = 0.004,0.013), but the BF(min) had no statistical significance in the two groups（P = 0.54）. AUC of D, BF(avg), and BF(max) is about 0.731, 0.753, and 0.724, respectively, all of their combined AUC diagnosis was 0.812. CONCLUSION: The early response of NPC after CRT can predict by IVIM’s diffusion parameters and ASL-related blood flow parameters.