Cesium-131 Sources for Brachytherapy

Low energy X and Gamma ray sources such as Cs-131 (9.7 Days T1/2, 30 keV) are extremelyuseful in cancer therapy with obvious advantages such as ease of shielding, useful range in tissue. SinceCs-131 is capable of forming insoluble metal complexes with metal salts such as AmmoniumMolybdophosphate, it is intended to exploit this property of Cesium in this study. The purpose of thepresent study is to explore the feasibility of commercially manufacturing radioactive sources of Cs-131technologically superior and better capable than existing ones, of providing uniform distribution ofradioactivity and desirable safety characteristics. We plan to accomplish this project in several steps:a. complex formation with a suitable metal as a substrate, from which Cesium does not dissociate, b.seed manufacture, consisting of central tungsten core coated with a suitable metal complex; filmmanufacture, consisting of suitable membrane coated with a suitable metal complex, c. evaluation ofradioactive source integrity against leakage using conventional procedures, and d. evaluation ofuniformity of dose distribution in the radioactive source and clinical potential by dose and dose ratemeasurements.