Magnetic Resonance with Diffusion and Dynamic Perfusion-Weighted Imaging in the Assessment of Early Chemoradiotherapy Response of Naso-Oropharyngeal Carcinoma

The purpose of this study was to differentiate post-chemoradiotherapy (CRT) changes from tumor persistence/recurrence in early follow-up naso-oropharyngeal carcinoma on magnetic resonance (MRI) with diffusion (DWI) and dynamic contrast-enhanced perfusion-weighted imaging (DCE-PWI). A total 37 patients were assessed MRI both for staging 4-month ending CRT. Mean apparent coefficient (ADC) values, area under the curve (AUC), K(trans) values calculated DWI DCE-PWI images, respectively. primary (ADC, AUC, K(trans)pre), post-CRT K(trans)post), trapezius muscle as a normative reference before after CRT K(trans)muscle pre post; AUCpost/muscle post:AUCpre/muscle (AUCpost/pre/muscle); K(trans)post/muscle post:K(trans)pre/muscle (K(trans)post/pre/muscle) assessed. In detecting changes, ADCpost > 1.33 × 10−3 mm2/s an increase >0.72 and/or >65.5% between ADCpre (ADCpost-pre; ADCpost-pre%) had 100% specificity, whereas hypointense signal intensity DWIb800 images showed specificity 80%. Although mean AUCpost/pre/muscle K(trans)post/pre/muscle similar (1.10 ± 0.58; 1.08 0.91) (1.09 0.11; 1.03 0.12), < 0.85 >1.20 suggested fibrosis inflammatory edema, carcinoma, our sample that mm2/s, ADCpost-pre% 65.5%, ADCpost-pre 0.72 identified specificity. less than fibrosis, more 1.20 indicated edema.