Whole-body diffusion-weighted magnetic resonance imaging with apparent diffusion coefficient mapping for staging patients with diffuse large B-cell lymphoma

Objective To design a whole-body MR protocol using exclusively diffusion-weighted imaging (DWI) with respiratory gating and to assess its value for lesion detection and staging in patients with diffuse large B-cell lymphoma (DLBCL), with integrated FDG PET/CT as the reference standard. Methods Fifteen patients underwent both whole-body DWI (b = 50, 400, 800 s/mm 2 ) and PET/CT for pretreatment staging. Lymph node and organ involvement were evaluated by qualitative and quantitative image analysis, including measurement of the mean apparent diffusion coefficient (ADC). Results A total of 296 lymph node regions in the 15 patients were analysed. Based on International Working Group size criteria alone, DWI findings matched PET/CT findings in 277 regions (94%) (kappa score = 0.85, P