 The translational objective of this study is to implement and evaluate a new imaging technology for rapid, single-scan multi-tracer PET imaging of these tracers. Current PET technology prohibits imaging of more than one tracer in a single scan since the imaging signals from each tracer cannot be distinguished by normal techniques; as such, separate scans with each tracer currently need to be acquired hours or days apart. Our group has developed techniques and algorithms for recovering individual-tracer images from rapidly-acquired multi-tracer PET data using dynamic imaging techniques. These methods have been tested through extensive simulations and verified experimentally in a canine model with spontaneously-occurring tumors. Refinement of the methods with more advanced algorithms is ongoing. The patient imaging studies of this protocol will be implemented in two phases. In Phase A, separate single-tracer imaging of each tracer will be performed. The data from these scans will be co-registered and combined to emulate multi-tracer scans, which will then be processed by the multi-tracer signal-separation algorithms. This will permit a direct comparison of imaging biomarkers from multi-tracer vs. single-tracer scans for each tracer. Such comparison techniques have been established by the investigators and have been accepted by peer review for testing multi-tracer signal-separation algorithms. Once statistically-significant evidence is obtained that multi-tracer scans can accurately provide the same imaging biomarkers as separate single-tracer scans, the imaging will transition to Phase Bin which actual multi-tracer scans will be performed. 