The development of hyperthermia as a practical cancer treatment has been hindered by difficulties in reliably heating small visceral masses. Current non-invasive techniques (ultrasound, microwaves, radiofrequency current, whole-body hyperthermia) do not permit the selective treatment of visceral masses less than 5 cm diameter, and many masses larger than this cannot be heated either. We have investigated an invasive hyperthermia technique utilizing ferromagnetic seeds. These are composed of a nickel-copper alloy of our own manufacture, and have a Curie Point of 51 C. These seeds can be surgically implanted into a tumor and, when exposed to an oscillating magnetic field, heat up to the Curie Point and stablize at that temperature. These seeds can be expected to produce good temperature homogeneity throughout the tumor volume and only moderate heating of adjacent tissues. The proposed studies are directed toward developing an adequate clinical foundation for eventual human studies with these thermoseeds. The studies will consist of toxicologic and clinical investigations as well as some developmental engineering work. 1. An adequeate number of thermoseeds will need to be produced for the animal studies. This will involve wire manufacture, annealing, and electroplating the seeds. 2. A magnetic induction system will be developed. The proposed system will permit the field to be oriented in any direction with respect to the body axis, and thereby allow great flexibility in thermoseed implantation. 3. Toxicologic investigations in rats will examine possible dissolution of the thermoseeds during prolonged body contact. 4. Phase I studies of hyperthermia alone, and hyperthermia with radiation, will be conducted in dogs with spontaneous and implanted tumors. The reproducibility and toxicity of heating with the thermoseeds will be examined.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA039041-02
Application #
3177708
Study Section
Radiation Study Section (RAD)
Project Start
1984-12-01
Project End
1987-11-30
Budget Start
1985-12-01
Budget End
1986-11-30
Support Year
2
Fiscal Year
1986
Total Cost
Indirect Cost
Name
University of Alabama Birmingham
Department
Type
Schools of Medicine
DUNS #
004514360
City
Birmingham
State
AL
Country
United States
Zip Code
35294
Brezovich, I A; Lilly, M B; Meredith, R F et al. (1990) Hyperthermia of pet animal tumours with self-regulating ferromagnetic thermoseeds. Int J Hyperthermia 6:117-30
Meredith, R F; Brezovich, I A; Weppelmann, B et al. (1989) Ferromagnetic thermoseeds: suitable for an afterloading interstitial implant. Int J Radiat Oncol Biol Phys 17:1341-6
Brezovich, I A; Meredith, R F (1989) Practical aspects of ferromagnetic thermoseed hyperthermia. Radiol Clin North Am 27:589-602