Perfluorocarbon emulsions in cancer therapy: preliminary observations on presently available formulations

Perfluorocarbon (PFC) emulsions, due to their favorable oxygen transporting properties, have been proposed as tumor sensitizers for application in both radiotherapy and chemotherapy. While this application is a very promising one it is by no means simple, and presently available formulations are inadequate. Intravenous administration of these emulsions can produce a severe hemodilution which tends to offset the desired effect; these emulsions can alter the pharmacokinetics of simultaneously administered drugs. Unless these variables are taken into account the risk of false negative and false positive results will be excessive. Of more serious concern are the profound disturbances produced by these emulsions in the reticuloendothelial system. Using two of the more popular PFC, Fluosol-DA and DMA/NONANE, we have shown that daily administration of these emulsions can produce 9-fold increases in liver size and 27-fold increases in spleen size. This problem appears to involve the surfactant used in both emulsions, pluronic F-68. It will be necessary to circumvent this problem before further study of their potential application can proceed.