89Zr-DFO-C4Fc-MUT foremost benefits from improved kinetic properties for PET imaging of brain tumors expressing PD-L1 as it generates an optimal contrast between the brain tumor and the contralateral hemisphere at 22h p.i. for the 89Zr-DFO-C4Fc-MUT against 168 h for 89Zr-DFO-C4. Here, CD274 is linked to brain neoplasm.