There have been reports of PD-L1 and metabolic imaging parameters demonstrating correlation[52–55] and no correlation.[56,57] PET also provides information on the metabolic state of the tumor microenvironment (TME), as the glucose analogue 18F-FDG is transported by cancer cells and active immune cells, such as tumor-infiltrating lymphocytes (TIA) and tumor-associated macrophages (TAM). Here, CD274 is linked to cancer.