Effect of intratumoral injections of a perfluorochemical emulsion on tumor radiosensitivity

Abstract

AbstractPast studies in several laboratories have shown that intravenous administration of perfluorochemical emulsions (PFC‐E) combined with the breathing of oxygen, carbogen, or hyperbaric oxygen improves the oxygenation of solid tumors and increases the response of these malignancies to radiation and cytotoxic drugs. It has been suggested that direct intratumoral (IT) injection of PFC‐E would also be effective in improving the response of tumors to radiation. The experiments reported here test this hypothesis, using a high quality PFC‐E (Oxygent™, Alliance Pharmaceutical Corp., San Diego, CA) and a well‐defined mouse tumor model system, EMT6 mouse mammary tumors implanted into syngeneic BALB/c Rw mice. Tumor response was assayed using both a clonogenic assay and a tumor growth assay. The IT injections tested did not improve the response of tumors to radiation in either air breathing or carbogen breathing hosts. In contrast, intravenous injections of Oxygent™, combined with carbogen breathing, were effective in increasing the response of tumors to irradiation. These studies provide additional evidence that intravenous administration of PFC‐E may be valuable as an adjunct to radiotherapy, but provide no evidence that the direct IT administration of these agents would be of value. © 1995 Wiley‐Liss, Inc.