Head and neck squamous cell carcinoma: Differentiation of histologic grade with standard- and high-b-value diffusion-weighted MRI

Background The correlation between the histologic grades and the apparent diffusion coefficient (ADC) in head and neck squamous cell carcinomas (HNSCCs) remains unclear. This study aimed to evaluate the potential of diffusion-weighted MRI (DW-MRI) at both standard and high b values to differentiate the histologic grades of HNSCC. Methods In all, 54 consecutive patients with HNSCCs (34 well-differentiated, 10 moderately differentiated, and 10 poorly differentiated) performed DW-MRIs at both b = 1000 and 2000 s/mm2 prior to biopsy or surgery. The ADC values were compared among the different histologic grades. Results The ADC values of well-differentiated and poorly differentiated HNSCC were significantly different at both b values (p < .001 in both). However, significant difference between moderately differentiated and poorly differentiated HNSCC was revealed at only b = 2000 s/mm2 (p = .014). Conclusions DW-MRIs at standard and high b values are helpful for differentiating histologic grades in HNSCC with better differentiation at a high b-value. (c) 2012 Wiley Periodicals, Inc. Head Neck, 2013