Tumour oxygenation measurements by F-19 magnetic resonance imaging of perfluorocarbons

Solid tumours are well known to be heterogeneous and contain a significant fraction of hypoxic cells, which are protected against the effects of radio therapy. A non-invasive method for measuring tissue oxygenation would there fore be useful. The F-19 magnetic resonance signals from perfluorocarbons a re sensitive to oxygen concentration. We have used this property to measure tumour oxygenation of the GH3 prolactinoma, RIF-1 fibrosarcoma and SaF sar coma in mice by fluorine magnetic resonance imaging (MRI) of intravenously injected perfluorocarbons which are taken up by macrophages in the tumour. We have also studied the injection of perfluorocarbons directly into the tu mour, which allows less of the tumour to be studied but has a higher succes s rate and gives values more consistent with Eppendorf polarographic electr ode measurements.