EGFR and neoplasm: The PAI method for determiningRA performed as anticipated, asBP reports on the concentration of EGFR available for binding. It also confirms our assumption that administrationof trace level ABY-029 (occupying <5% of the total receptor) holdstrue. Another inherent assumption ofthe compartment model for PAI is the adiabatic approximation for tissuehomogeneity, which assumes instantaneous mixing of the imaging agentswithin the tumor “compartment”., If this assumption was true, in vivo BP shouldreach a plateau instantaneously after paired-agent administrationand hold constant.