RÉSUMÉ
Purpose of the Review: We present an overview of recent advances in positron emission tomography (PET) diagnostics as applied to the study of cancer, specifically as a tool to study in vivo cancer biology and to direct targeted cancer therapy. The review is directed to translational and clinical cancer investigators who may not be familiar with these applications of PET cancer diagnostics, but whose research might benefit from these advancing tools. Recent Findings: We highlight recent advances in 3 areas: (1) the translation of PET imaging cancer biomarkers to clinical trials; (2) methods for measuring cancer metabolism in vivo in patients; and (3) advances in PET instrumentation, including total-body PET, that enable new methodologies. We emphasize approaches that have been translated to human studies. Summary: PET imaging methodology enables unique in vivo cancer diagnostics that go beyond cancer detection and staging, providing an improved ability to guide cancer treatment and an increased understanding of in vivo human cancer biology.