—Glioblastomas are known to be heavily infiltrated by tumor-associated myeloid cells (TAMCs).39 As TAMCs are known to suppress antitumor immune responses and promote tumor cell growth, their quantification by noninvasive imaging could potentially facilitate patient selection for TAMC-targeted therapies as well as for the assessment of treatment response.40 The uniform expression of the cell surface marker integrin CD11b on TAMCs renders CD11b as a potential target for PET imaging. This evidence concerns the gene ITGAM and neoplasm.