Clinical cases are presented in a way that is familiar to physicians from their training in nuclear medicine services. Each case starts with key clinical information or background, followed by well-displayed PET CT images, along with pertinent questions highlighting the key findings and explanation, as well as the importance in diagnosis and clinical implications on separate pages. Clinical and imaging key findings and final impressions are highlighted throughout along with qualitative and quantitative demonstrations of phenotypic nature of modern PET imaging. Written by two nuclear medicine PET specialists with decades of first-hand clinical experience, this is an ideal guide for nuclear medicine attending physicians, diagnostic radiologists, medical and surgical oncologists, and relevant trainees.