title: Comparison of Kinetic Models for Dual-Tracer Receptor Concentration Imaging in Tumors.
abstract: Molecular differences between cancerous and healthy tissue have become key targets for novel therapeutics specific to tumor receptors. However, cancer cell receptor expression can vary within and amongst different tumors, making strategies that can quantify receptor concentrationin vivocritical for the progression of targeted therapies. Recently a dual-tracer imaging approach capable of providing quantitative measures of receptor concentrationin vivowas developed. It relies on the simultaneous injection and imaging of receptor-targeted tracer and an untargeted tracer (to account for non-specific uptake of the targeted tracer). Early implementations of this approach have been structured on existing "reference tissue" imaging methods that have not been optimized for or validated in dual-tracer imaging. Using simulations and mouse tumor model experimental data, the salient findings in this study were that all widely used reference tissue kinetic models can be used for dual-tracer imaging, with the linearized simplified reference tissue model offering a good balance of accuracy and computational efficiency. Moreover, an alternate version of the full two-compartment reference tissue model can be employed accurately by assuming that theK1s of the targeted and untargeted tracers are similar to avoid assuming an instantaneous equilibrium between bound and free states (made by all other models).
authors.affiliation: Biomedical Engineering Despartment, Illinois Institute of Technology, Chicago IL 60616, USA.
authors.forename: Nazanin
authors.initials: N
authors.lastname: Hamzei
authors.affiliation: Thayer School of Engineering, Dartmouth College, Hanover NH 03755, USA.
authors.forename: Kimberley S
authors.initials: KS
authors.lastname: Samkoe
authors.affiliation: Department of Surgery, Dartmouth Medical School, Hanover NH 03755, USA.
authors.forename: Jonathan T
authors.initials: JT
authors.lastname: Elliott
authors.affiliation: Wellman Center for Photo medicine, Massachusetts General Hospital, Boston MA 02114, USA.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Holt
authors.forename: Jason R
authors.initials: JR
authors.lastname: Gunn
authors.forename: Tayyaba
authors.initials: T
authors.lastname: Hasan
authors.forename: Brian W
authors.initials: BW
authors.lastname: Pogue
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Tichauer