Positron emission tomography (PET) with the metabolic radiotracer 2-deoxy-2-[<sup>18</sup>F]fluoro-D-glucose (<sup>18</sup>F-FDG or FDG) has been shown to be useful in determining the presence of or absence of viable tumor after chemotherapy for seminoma, but its role with non-seminomatous germ cell tumors (NSGCTs) and other clinical scenarios is limited.