title: 9:30-9:45. First Pass FDG Measured Blood Flow in Tumors: A Comparison with O-15 Labeled Water Measured Blood Flow.
abstract: The purpose of this study was to determine if the first-pass of FDG can be used to measure regional blood flow in tumors in the absence of perfusion imaging with a known blood flow tracer.PET scans were obtained in patients being evaluated for tumor perfusion and metabolism in a Phase I dose escalating protocol for Endostatin, a novel antiangiogenic agent. A two minutes perfusion scan was done with a bolus injection of 60 mCi of O-15 labeled water followed by a 10 mCi dose of FDG and four sequential scans consisting of a first pass two minutes scan and three 15 minutes scans. Regions of interest were drawn on two tumor sites for each scan. Blood flow was computed using a one-compartment model previously published by the authors. Linear regression analysis was carried out between the first pass FDG measured blood flow and O-15 measured blood flow (Figure 1).Blood flow estimated from the first pass of FDG was linearly correlated with O-15 measured blood flow with an intercept of 0.01, slope of 0.86, and r squared regression coefficient of 0.74 (R = 0.86) for blood flow values of up to 0.6 ml/min/gm of tissue. These results suggests that in the absence of a perfusion tracer, the first pass of FDG provides an estimate of perfusion in a tumor within the limitations of incomplete extraction of FDG compared to O-15 water.
authors.affiliation: University of Texas Medical School - Houston and the U.T. M.D. Anderson Cancer Center, Houston, TX, USA
authors.initials: N
authors.lastname: Mullani
authors.initials: R
authors.lastname: Herbst
authors.initials: J
authors.lastname: Abbruzzese
authors.initials: B
authors.lastname: Barron
authors.initials: L
authors.lastname: Lamki
authors.initials: C
authors.lastname: Charnsangavej
authors.initials: E
authors.lastname: Kim
authors.initials: H
authors.lastname: Tran
authors.initials: A
authors.lastname: Jiwani
authors.initials: K
authors.lastname: Gould