Molecular imaging with 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET), and more recently with PET–CT, provides accurate and detailed information on the extent and response to treatment for many common cancers. Despite its superiority over conventional imaging, FDG-PET availability and funding vary widely between developed countries. Different health-care providers reach widely different conclusions about the use of expensive PET scans to replace or supplement cheaper conventional...