Intratumoral pO₂ measured using a new oxygen sensitive paramagnetic material, gloxy

There is increasing evidence that tumor oxygenation is clinically important in pre-dicting tumor response to radiation, chemotherapy and/or overall prognosis (Vaupel, et al., 1989; Hall, 1988). More recently, tumor hypoxia has been implicated in promoting sur-vival of tumor cell phenotypes that are more resistant and have lost their apoptotic (self- killing) ability (Giaccia, 1996; Shrieve and Begg, 1985). A valid method for obtaining measurements of intratumor oxygen tensions repeatedly and non-invasively is therefore very desirable. Electron Paramagnetic Resonance (EPR) oximetry is a recently developed technique which has the potential to provide such data. Its full use will be facilitated by the development of oxygen-sensitive materials which can be used under the various cir-cumstances in which repeated measurements of pO2 are desired.