38 Chapter 2 SUPPLEMENTARY DATA Participating centers Patients were enrolled in the Radboud university medical center (UMC), UMC Groningen, Amsterdam UMC and Erasmus medical center (MC). Patient imaging CT-scan The CT acquisition and reconstructions were performed according to local protocols for Canon Aquilion One GENESIS Edition (Radboudumc), Siemens Force/Flash (UMC Groningen) scanner, Discovery CT750 (Amsterdam UMC) and Siemens Somatom (Erasmus MC). Acquisition protocols were as follows;100 or 120 kV protocol (automatic exposure control (AEC) with standard deviation (SD) of 15), with auto mA 120-500, noise index of 25, at a rotation speed of 0.275-0.5 sec. Scan range included chest, abdomen and pelvis. Reconstruction was performed by the Canon Aquilion scanner using adaptive iterative dose reduction 3dimensional enhance (AIDR 3Denh) in combination with FC08 filter to create axial in 1mm/0.8mm and axial, coronal and sagital in 5mm/4mm slices and FC86 filter to create axial in 1mm/0.8mm and axial in 5mm/4mm and 10/3 MIP axial. Images from the Flash/Force scanner were reconstructed using SAFIRE iterative reconstructions program 2 to create 1mm slices with an increment of 0.7mm for chest reconstructions and 2mm slices with an increment of 1,5mm in slices of the abdomen and pelvis. CT images of the Discovery CT750 were reconstructed using the adaptive statistical iterative reconstruction (ASIR) algorithm at 60-70% to create 0.625 mm axial and coronal slices of the chest and 3mm slices of the abdomen and pelvis. SAFIRE iterative reconstructions were also used to reconstruct images from the Siemens Somatom to create either axial in 3mm/3mm and 3mm/2mm coronal/sagittal or axial in 1mm/0.8mm Image analysis was performed on the venous phase scans after intravenous injection of iodinated contrast at 100-150 ml/kg body weight with bolus tracking at a delay of 30-80 sec (chest - abdomen) and maximal slice thickness of 5.0 mm. Patient imaging – PET/CT [18F]FDG-PET/CT was performed according to European Association of Nuclear Medicine (EANM) guidelines version 1.0  and the 89Zr-imaging procedure was harmonized between participating, EARL-accredited centers (PET/CT-systems). Patients underwent [89Zr]Zr-DFO-girentuximabPET/CT 4 days after intravenous (IV) injection of 37 MBq [89Zr]Zr-DFO-girentuximab (protein dose 5 mg). For both PET scans, patients were scanned from the head to upper thigh in up to 6 consecutive bed positions, during 5 minutes for each bed position with a 64-slice PET/CT camera (Biograph mCT, Siemens in Radboudumc, UMC Groningen and Erasmus MC; Gemini TF or Ingenuity TF, Philips in the Amsterdam UMC). All data were corrected for dead time, scatter, randoms, decay and tissue attenuation, with a final reconstruction resolution of 7 mm.