Clinical Evaluation of the New Hypoxia Imaging Agent HX4
Status:
Completed
Trial end date:
2010-05-01
Target enrollment:
Participant gender:
Summary
Positron Emission Tomography (PET) with fluorine-18 fluoromisonidazole (FMISO) has been used
for several years as a non invasive imaging technique to study tumor hypoxia. Several
experimental and clinical studies have indicated that FMISO uptake of tissues is correlated
with tissue oxygen tension and that FMSO PET allows non-invasive differentiation between
hypoxic and normoxic tumors. Currently, FMISO-PET represents the best characterized and
validated noninvasive hypoxia imaging technique. Nevertheless, clinical studies have also
shown the limitations of FMISO PET. Accumulation of FMISO in hypoxic tumors is relatively
low, resulting in a low contrast between hypoxic tumors and surrounding normal tissues. In
addition, imaging needs to be started relatively late after tracer injection (about 3 hours
post-injection), when a significant percentage of the fluorine-18 label has already decayed
and the count statistics of the PET images are relatively low. Because of these limitations,
FMISO PET is still only used at a few research centers, despite high clinical interest in
hypoxia imaging.