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 ( BFavg), minimum blood flow (BFmin), and maximum blood flow (BFmax). 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 BFavg and BFmax of the CR group were higher than those of the PR group(p = 0.004,0.013), but the BFmin had no statistical significance in the two groups(P = 0.54). AUC of D, BFavg, and BFmax 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.
Keywords: 3DpCASL, three-dimensional quasi-continuous arterial spin labeling; ADC, apparent diffusion coefficient; AUC, area under the curve; Arterial spin labeling; BFavg, average of blood flow; BFmax, maximum blood flow; BFmin, minimum blood flow; CR, complete remission; CRT, chemoradiotherapy; Chemoradiotherapy; D*, pseudo-diffusion coefficient; D, pure diffusion coefficient; DCE-MRI, dynamic contrast-enhanced magnetic resonance imaging; IVIM-DWI, intravoxel incoherent motion diffusion-weighted imaging; Intravoxel incoherent motion diffusion-weighted imaging; NPC, nasopharyngeal carcinoma; Nasopharyngeal carcinoma; PR, partial remission; f, perfusion fraction.
© 2022 Published by Elsevier Ltd.