PIXE ANALYSIS OF A MURINE FIBROSARCOMA TUMOR FOR PROTON THERAPY COMBINED WITH THE CHEMOTHERAPEUTIC AGENT CISPLATIN

Abstract

Concentrations of the chemotherapeutic agent, cis-diamminedichloro-platinum(II) (CDDP) in NFSa fibrosarcoma tumors were investigated using a conventional PIXE analysis on the basis of an internal standard method to study enhancement of antitumor effects caused by proton therapy combined with CDDP treatment. Results of the PIXE analysis showed that platinum concentration of the tumors treated with CDDP at a single dose of 10 mg/kg was 2.0±0.1 µg/g and persisted at the level at least 6 hours after the administration. The present study demonstrated that the presence of CDDP in the tumor caused an enhanced therapeutic effect on tumor growth delay when CDDP treatment was combined with post proton-irradiation in comparison with CDDP treatment alone or proton therapy alone.