Potential application of perfluorochemicals in cancer therapy

PFC emulsions, because of their excellent oxygen-transporting properties and possibly other properties as well, have broad and promising potential in cancer therapy. Although this potential is readily apparent to both laboratory and clinical investigators who are concerned with tumor hypoxia, it should be equally apparent that the formulations that are currently available are wholly inappropriate for such an application. The sublethal toxicities of these emulsions may appear to indicate a poor prognosis for this approach, but they may be a blessing in disguise. All known approaches to tumor hypoxia are limited by our inability to administer enough of the agents to be effective. In many cases, the limiting factor was not uncovered until the approach had been introduced into clinical trials. Had we relied on such parameters as lethality in the case of PFC emulsions, the same mistake might have been made here. Instead, the death of a single rat has caused us to focus our attention on what would surely have produced major problems in the initial clinical trials. Recognition of the sublethal toxic effects of PFC emulsions at this early stage should allow us to optimize our formulations at the preclinical stage, thereby increasing the likelihood that PFC emulsions will someday live up to their full potential.