SBIR-STTR Award

Encapsulated radioactive sources emitting ionizing radiation in the form of high energy photons are widely used for treatment of cancer, known as brachytherapy. In this treatment radioactive sources are placed directly in the tumor volume (interstitial brachytherapy) or in close proximity to the tumor in body cavities (intracavitary irradiation). Recently there has been considerable interest in the development of brachytherapy sources emitting lower energy photons in the energy range of 20 to 100 keV because they offer advantages over higher energy photon emitters in terms of ease of radiation shielding within the patient and radiation protection of medical personnel. Following this trend, Sm-14S sources for brachytherapy were developed at Brookhaven National Laboratory (BNL). These sources emit photons in the energy range of 38 to 45 keV and decay with a halflife of 340 days. In addition to the advantages of the ease of radiation shielding, Sm-145 sources emit photons with energies just above the K-absorption edge of iodine (33.3 keV). This characteristic makes Sm-145 sources an ideal candidate for radiation enhancement with thymidine analog iodinated deoxyuridine (lUdR) by stimulating cascades of Auger electrons resulting from photoionization of the iodine. Thus, Sm-145 offers a new possibility for maximizing the effects of lUdR radiosensitization in combination with brachytherapy, which are being investigated by NCI sponsored protocols at Yale, Ohio State and BNL. This project will investigate the feasibility of producing a high quality, leakage free, encapsulated source of Sm-145 and commercializing this new brachytherapy source.Awardee's statement of the potential commercial applications of the research:This research will result in the commercial development of encapsulated sources of Sm-145 for brachytherapy of cancer. These sources offer considerable advantages in terms of ease of radiation shielding and enhanced lUdR radiosensitation in combined modality treatment of lUdR plus brachytherapy.National Cancer Institute (NCI)

Encapsulated radioactive sources emitting ionizing radiation in the form of high energy photons are widely used for treatment of cancer known as brachytherapy. In this treatment radioactive sources are placed directly in the tumor volume (interstitial brachytherapy) or in close proximity to the tumor in body cavities (intracavitary irradiation). Recently there has been considerable mterest in the development of brachytherapy sources emitting lower energy photons in the energy range of 10 to 100 keV because they offer advantages over higher energy photon emitters in terms of ease of ra iation shielding within the patient, and radiation protection of medical personnel, patient and his family. Following this trend, Samarium 145 sources for brach /therapy were developed by BEST INDUSTRIES in the Phase I grant. These sources emit photons primarily in the energy range of 38 to 45 keV and decay with a half life of 340 days. In addition to the advantazes of the ease of radiation shielding, Samarium 145 sources emit photons with energies just above the K absorption edge of iodine (33.2 ke~ ). This characteristic makes Samarium 145 sources an ideal candidate for radiation enhancementwith thymidine analog iodinated deoxyuridine (lUdR) by stimulating cascades of Auger electrons resulting from photoionization of the iodine. Thus, Samarium 145 offers a new possibility for maximizing the effects of lUdR radlosensitization in combination with brachytherapy. Phase II will develop prototype Samarium 145 sources, determine their physical dosimetric characteristics and test their efficacy in an animal tumor model.Awardee's statement of the potential commercial applications of the research:This research will result in the commercial development of encapsulated sources of Samarium 145 for brachytherapy of cancer. These sources offer considerable advantages in terms of ease of radiation shielding within the patient as well as for medical personnel and family members and enhanced lUdR radiosensitization in combined modality treatment of lUdR plus brachytherapy.National Cancer Institute (NCI)National Cancer Institute (NCI)