Human GIST xenografts are FDG-avid on PET scan. A. This P0 mouse underwent tumor xenografting into the right renal capsule. At 16.1 weeks after implantation, we performed imaging via PET scan. The arrow denotes tumor uptake of FDG (SUVmax 2.2, SUVmin 1.8, SUVmean 2.0) by PET scan as indicated by the arrow in A. The FDG uptake in the heart and the brown fat of the shoulder girdles serve as a positive control. B. Gross photograph of the corresponding FDG-avid tumor measuring 12 × 10.5 mm in the same mouse.