A method of controlling metastasis of a cancerous tumor in a patient is disclosed. The method comprises administering a perfluorocarbon compound (PFC) emulsion to the patient at intervals of from about 3 to 14 days during a treatment period. PFC emulsion is administered initially in an amount of from about 2 to about 15 milliliters per kilogram of patient body weight. Subsequently administration of PFC emulsion do not exceed about 15 milliliters per kilogram of body weight. Oxygen is administered daily for at least three days following each administration of PFC emulsion & preferably every day during the treatment period. Radiation and/or chemothereapeutic agents may be administered to the patient in conjunction with the administration of PFC emulsion and oxygen.