Magnetically enhanced radionuclide therapy

Radiopharmaceutical therapy is an increasingly common treatment for cancer. This therapy involves the injection of radiolabeled tumor-specific agents into the patient with subsequent preferential accumulation in the tumor sites. Particulate radiation (usually beta particles) emitted by the radioisotope kill or damage the tumor cells. The effectiveness of radiopharmaceutical therapy, however, is limited by the size of the tumor treated. Energetic particles can easily exit small tumors before they are able to deposit their energy and inflict significant damage. Methods: We propose the use of a static magnetic field to be applied after the radiopharmaceutical has localized in the tumors, constraining these particles to helical paths. This application would result in substantially confining the emitted particles within the tumor's boundaries, thus increasing radiation dose to the tumor. Results: Computer simulations of radionuclide treatments using ¹³¹I, ¹⁸⁶Re and ⁹⁰Y show that a magnetic field of 10 Tesla can increase the radiation dose achieved by conventional radionuclide therapy by up to 71%. In addition, total radiation dose to surrounding normal tissues is substantially reduced. Conclusion: Magnetically enhanced radionuclide therapy (MERIT) therefore shows promise as an effective treatment of cancer and warrants further study.