Buried emanation; the development of seeds for permanent implantation

PURPOSE: To chronicle the development of radioactive sources for permanent implantation. METHODS AND MATERIALS: Review of contemporary literature. RESULTS: The value of ionizing radiation in the treatment of malignancy was appreciated soon after Roentgen's and Becquerel's discoveries. Brachytherapy was developed to treat tumors that were poorly controlled by early X-ray equipment. Sources and techniques for permanent implantation were devised in the first quarter of the 20th century. CONCLUSIONS: Long before the creation of artificial isotopes, pioneering physicists and clinicians fashioned seeds from naturally occurring radionuclides and ingenuity.