[Present status of brachytherapy].

High dose rate, remote-afterloading intracavitary irradiation (RALS) and low dose rate, interstitial irradiation were discussed. In Japan, RALS is now a standard treatment for uterine cervix carcinoma. In interstitial radiotherapy, radium sources, because of their poor conditions of protection and excessively long half-life, are being replaced by several new radioactive elements, such as 60Co, 125I, 125Cs and 192Ir. These have suitable characteristics for afterloading and safety protection. Among them 192Ir has become common source, not only for intraoral cancer, but also various other tumors including rectal, breast, and bile duct cancers.