Improved efficacy of SnET2 mediated PDT with the simultaneous application of selective hyperthermia

The results of experiments combining laser hyperthermia (LHT) wit photodynamic therapy (PDT) in the treatment of cancerous tumors have been very encouraging. Typically treatments have been sequential, employing separate hyperthermia and PDT systems. Sequential application of these therapies, however, fails to maximize the synergistic effects of combined, simultaneous treatment. This paper reports the results of an SBIR funded Phase I project intended to develop a system for precise simultaneous delivery of both LHT and PDT light, and to measure the synergistic effects os simultaneously applied LHT and PDT with both Photofrin II- and SnET2-mediated PDT. A system was developed that would allow the use to specify all treatment parameters and then deliver the combined light to the treatment site. Thermal and optical feedback in the system provide stability and precise control during the treatment. The system architecture, the computer control system, and the results obtained from bench-testing the system are presented in this paper. The system was then tested in a small animal tumor model. This paper will discuss the study protocol and the experimental results.