(A) Representative PET/contrast-enhanced T₁W (T1wCE) MR fusion images taken pre-surgery from patient 1 (control) at 48 and 72 hours post-injection of ⁸⁹Zr-DFO-Atezolizumab. (B) Representative H&E and CD4, CD8, and PD-L1 IHC staining from the patient 1 resected tumor specimen (Scale bar: 50 μm, Magnification: × 38). (C) Representative PET/T1wCE MR fusion images taken pre-surgery from patient 4 (neoPembrolizumab) at 72 hours post-injection of ⁸⁹Zr-DFO-Atezolizumab. (D) Representative T1wCE MR fusion image only (left column), fusion with PET (middle column), and perfusion-weighted imaging (PWI) (right column) from patient 7 demonstrating heterogeneous ⁸⁹Zr-DFO-Atezolizumab uptake and vascular permeability. The dashed boxes highlight either gadolinium positive–negative and/or PET-positive–negative regions of interest across corresponding T1wCE MR, PET/T1wCE MR fusion, and PWI image slices.