Abstract: Conventional internal radiation therapy has used implants, such as granules or seeds, each of which includes a radiation source for implantation within the patient. In contrast to conventional internal radiation therapy, disclosed herein is a radioactive flowable cement capable of curing to form radioactive cured cement, such that the radioactive cured cement may simultaneously provide radiation therapy, bone repair and pain management. Radioactive cement may allow for the convenient introduction of a suitable volume of radioactive material to a target site within the patient's body in a single minimally invasive procedure, as compared with the conventional need for precise implantation locations of numerous radioactive granules. In further contrast to conventional methods, radioactive cement may provide a distributed radioactive source, such that the radioactive dose rate across the target tissue (e.g., bone) can be more constant.