Abstract
To establish a method of selective hyperthermia for deep tumors, hematoporphyrine liposomal magnetite (HP-LM) was prepared, and administered through intra-arterial catheter connected to a subcutaneous infusion port in a rabbit previously transplanted with VX-2 tumor in the thigh. Effective methods of HP-LM administration and tumor heating in high-frequency inductive heating are discussed. The results of our study showed that by using an intraarterial infusion port, HP-LM could be administered without damaging the tumor feeding vessels. Bi-weekly administration of HP-LM result in gradual washout of HP-LM and only transient anti-tumor effect could be achieved by heating once per week. Heating at least twice per week was thought to be necessary obtain long term anti tumor effects. To enhance the anti-tumor effect, concentration of HP-LM in the tumor must be conserved against the washout caused by blood flow. Frequent administration of HP-LM through the infusion port may by necessary. Optimal antitumor effect could be achieved by heating the tumor immediately after administration of HP-LM and heating intermittently.
