FDG-PET/CT images from a 25-year-old woman with PMBCL who progressed and died under treatment with R-MACOP-B. (A) FDG-PET images (maximum intensity projection view and transverse slices at 2 different levels) demonstrate high FDG uptake in a bulky mediastinal mass; the green circle defines a volume of interest where the MTV is automatically segmented with a 25% SUV_max threshold. MTV limits are displayed in green around the mediastinal tumor. SUV_max = 29; TLG = 6706, falling in the high-risk category. (B) CT with the projections of the MTV contours segmented on FDG-PET. (C) Fused FDG-PET and CT images. Courtesy of Dr Luca Ceriani.