ABSTRACT
A variety of therapeutic agents are under evaluation in nuclear medicine practice or clinical trials. The basic goal of radiation therapy is to ensure that enough radiation-absorbed dose is delivered to tumor without causing undesired effects in healthy tissues. A number of quantities have been studied for many years to relate radiation exposure to safety and risk evaluations. The Medical Internal Radiation Dose Dose Estimate Reports contain radiation dosimetry for particular radiopharmaceuticals, along with the kinetic model employed. The goal of all forms of radiation therapy against cancer is to give lethal doses of ionizing radiation to malignant cells while not exceeding the radiation tolerance of involved normal tissues. Hepatotoxicity with labeled 90Y labeled microspheres was suggested to be lower than would have been expected from knowledge of dose-related toxicity from external sources of radiation.
