RT Journal Article
SR Electronic
T1 Diffusion-Weighted Imaging to Assess HPV-Positive versus HPV-Negative Oropharyngeal Squamous Cell Carcinoma: The Importance of b-Values
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 905
OP 912
DO 10.3174/ajnr.A7521
VO 43
IS 6
A1 Lenoir, V.
A1 Delattre, B.M.A.
A1 M'RaD, Y.
A1 De Vito, C.
A1 de Perrot, T.
A1 Becker, M.
YR 2022
UL http://www.ajnr.org/content/43/6/905.abstract
AB BACKGROUND AND PURPOSE: Controversy exists as to whether ADC histograms are capable to distinguish human papillomavirus–positive (HPV+) from human papillomavirus–negative (HPV–) oropharyngeal squamous cell carcinoma. We investigated how the choice of b-values influences the capability of ADC histograms to distinguish between the two tumor types.MATERIALS AND METHODS: Thirty-four consecutive patients with histologically proved primary oropharyngeal squamous cell carcinoma (11 HPV+ and 23 HPV–) underwent 3T MR imaging with a single-shot EPI DWI sequence with 6 b-values (0, 50, 100, 500, 750, 1000 s/mm2). Monoexponentially calculated perfusion-sensitive (including b=0 s/mm2) and perfusion-insensitive/true diffusion ADC maps (with b ≥ 100 s/mm2 as the lowest b-value) were generated using Matlab. The choice of b-values included 2 b-values (ADCb0–1000, ADCb100–1000, ADCb500–1000, ADCb750–1000) and 3–6 b-values (ADCb0–750–1000, ADCb0–500–750–1000, ADCb0–50–100–1000, ADCb0–50–100–750–1000, ADCb0–50–100–500–750–1000). Readers blinded to the HPV– status contoured all tumors. ROIs were then copied onto ADC maps, and their histograms were compared.RESULTS: ADC histogram metrics in HPV+ and HPV– oropharyngeal squamous cell carcinoma changed significantly depending on the b-values. The mean ADC was lower, and skewness was higher in HPV+ than in HPV– oropharyngeal squamous cell carcinoma only for ADCb0–1000, ADCb0–750–1000, and ADCb0–500–750–1000 (P < .05), allowing distinction between the 2 tumor types. Kurtosis was significantly higher in HPV+ versus HPV– oropharyngeal squamous cell carcinoma for all b-value combinations except 2 perfusion-insensitive maps (ADCb500–1000 and ADCb750–1000). Among all b-value combinations, kurtosis on ADCb0–1000 had the highest diagnostic performance to distinguish HPV+ from HPV– oropharyngeal squamous cell carcinoma (area under the curve = 0.893; sensitivity = 100%, specificity = 82.6%). Acquiring multiple b-values for ADC calculation did not improve the distinction between HPV+ and HPV– oropharyngeal squamous cell carcinoma.CONCLUSIONS: The choice of b-values significantly affects ADC histogram metrics in oropharyngeal squamous cell carcinoma. Distinguishing HPV+ from HPV– oropharyngeal squamous cell carcinoma is best possible on the ADCb0–1000 map.AJCCAmerican Joint Committee on CancerAUCarea under the curveHNSCChead and neck squamous cell carcinomaHPV+human papillomavirus positiveHPV–human papillomavirus negativeOPSCCoropharyngeal squamous cell carcinoma