Application of multidimensional diffusion-weighted magnetic resonance imaging in nasopharyngeal carcinoma: a...

The microstructural diffusional heterogeneity of nasopharyngeal carcinoma (NPC) impacts outcome assessment. This study aims to investigate the potential of multidimensional diffusion-weighted magnetic resonance imaging (MDD-MRI) in evaluating microscopic diffusion characteristics of NPC.

Sixty-six NPC patients underwent MDD-MRI to derive microscopic diffusion metrics, including anisotropic mean kurtosis (MK), isotropic MK, total MK, and microscopic fractional anisotropy (FA). Macroscopic metrics, such as the apparent diffusion coefficient (ADC), along with parameters from diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI), were also analysed for comparison. Differences between NPC and normal tissues, as well as among pathological subtypes, clinical stages, and Epstein-Barr virus infection statuses, were assessed. Receiver operating characteristic curve analysis evaluated the ability to distinguish NPC from normal tissue. Spearman's correlation analysis examined associations between diffusion metrics and primary tumour (T) stages.

NPC tissues exhibited lower ADC (P<.001) and higher DKI-related MK (MK_K; P<.001) compared to normal nasopharyngeal tissues, with area under the curve values of 0.968 (95 % CI: 0.926-1) and 0.749 (95 % CI: 0.633-0.865) for ADC and MK_K, respectively. Microscopic metrics and ADC correlated with T stages: microscopic FA (rho = 0.52, P<.001), anisotropic MK (rho = 0.38, P=.002), isotropic MK (rho = 0.27, P=.03), total MK (rho = 0.32, P=.009), and ADC (rho = -0.36, P=.003).

MDD-MRI is a valuable tool for assessing NPC's microscopic characteristics, possibly improves T-stage evaluation beyond conventional ADC.