Intravoxel incoherent motion diffusion-weighted imaging for oropharyngeal squamous cell carcinoma: Correlation with human papillomavirus Status

purpose: to investigate the relationships between imaging parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and HPV status in oropharyngeal squamous cell carcinoma (OPSCC). materials and methods: 73 patients with a new diagnosis of OPSCC were enrolled in the present study. MRI including IVIM-DWI with nine b value (range 0-800 s/mm(2)) was acquired in all patients. primary tumor (PT) and the largest metastatic lymph node (LN), if present, were volumetrically contoured and the tissue diffusion coefficient D-t, perfusion fraction f and perfusion-related diffusion coefficient D* were estimated by a bi-exponential fit. the apparent diffusion coefficient (ADC) was also estimated by a mono-exponential fit. The predictive power of the most relevant patient/tumor characteristics and image-based features in determining the HPV status was assessed.Results: 67 PTs and 67 metastatic LNs were analyzed. significant differences in ADC and D t values among HPV-positive and HPV-negative patients were found for PTs (p = 0.003 and p < 0.001, respectively), while a trend toward significance in D-t was reported for LNs (p = 0.066). the perfusion-related parameters, f, D* and D* x f, were not related to HPV status. the best predictive model for HPV positivity was obtained combining alcohol intake and smoke habits with D-t values of PTs (accuracy = 80.8%, sensitivity = 85.7%, specificity = 64.7%).conclusion: significant correlations were found between IVIM-DWI and HPV status in OPSCCs. the perfusion- free diffusion coefficient, D-t, may better reflect the HPV-related tumor differences compared to ADC, whereas the perfusion-related parameters were not able to reliably discriminate HPV-positive from HPV-negative OPSCC.