This study examines the diagnostic capacity of using a different CT scan. Dynamic Contrast Enhanced -CT(DCE-CT). DCE-CT and FDG-PET/CT scans give different information about the SPN and the investigators will look to see if information from either scan or combined information from both scans may be better in the diagnosis of early stage lung cancer. The investigators will also undertake a review of previous studies that have used these scans and use data from both the review and the trial to look at the cost effectiveness of using DCE-CT in the diagnosis of SPN.