[General remarks on brachytherapy].

Brachytherapy has long been used because its therapeutic gain factor is high. The high-dose-rate remote after loading system (RALS) that enables therapists to treat patients without any radiation exposure recently has become the mainstream method and has been used in preference to low-dose-rate brachytherapy. 192Ir fine seeds were developed to expand the number of diseases treated and to increase the precision of treatment through computerization. However, because of new adaptations of brachytherapy and its use with external irradiation and other techniques, new issues have been generated as a result of the technological advances in external beam radiotherapy. The current status of brachytherapy is summarized, and information on the cautions and future views for developments and problems in brachytherapy are given in this report.