Endostatin is a novel antiangiogenic agent currently in phase I trials. In the context of this trial, we are evaluating the use of non-invasive imaging with PET to determine the relationship between tumor blood flow and glucose metabolism in imaged tumors from treated patients. Ten patients have been treated with escalating daily iv Endostatin doses of 30 to 180 mg/m2. PET images were obtained before the start of therapy and again after 28 days of treatment. Each patient was scanned with Oxygen-15 labeled water for estimation of tumor blood flow and Flourine-18 labeled FDG to estimate tumor metabolic activity. In most cases, two distinct tumor-bearing sites were analyzed in each patient. Thus, a total of 19 tumors were imaged. Regional blood flow and standard uptake values (SUV) were computed at baseline and 28 days post treatment and the percentage change in blood flow and SUV plotted as a function of Endostatin dose. Both blood flow and glucose metabolism in the imaged tumors were observed to increase in patients treated with ≤60 mg/m2/d, but became uncoupled in the tumors imaged from patients treated at the 180 mg/m2/d dose level. Thus, in patients receiving Endostatin at a dose of 180 mg/m2/d, blood flow decreased but glucose metabolism increased. This relationship is displayed in Figure 1 below.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging