[Clinical experience with short-term afterloading therapy in comparison with conventional brachytherapy in the treatment of gynecologic tumors].

Abstract

The short-term afterloading therapy (AL-ST) with high dose rates (DR) and remote control prevents the risk of a radiation exposure of the staff, facilitates the optimization of the dose distribution in space, makes the treatment easier for patients and hospital, and allows a considerable increase of the treatment capacity without additional need of staff or capital. AL-ST works with another dose distribution in time than the conventional brachytherapy, so a higher fractionation of high-dose-rate afterloading is substituted for the classical protraction of low-dose-rate brachytherapy. 2072 patients with gynecologic tumors were treated by AL-ST between 1974 and 1983. 1762 out of them (964 carcinomas of the cervix, 677 carcinomas of the body, and 121 vaginal tumors, metastases and urethral carcinomas) could be checked up for at least twelve months up to more than five years, which allowed an evaluation with regard to recurrence-free survival rate, local absence of tumors, and side effects. The five-year survival rates obtained by primary and post-operative AL-ST are compared to historical control groups of our own hospital and to the international results. The results, related to the stages, are at least equivalent; several groups show a statistically significant improvement compared to conventional brachytherapy. The incidence of early and late reactions in bladder and rectum showed a statistically significant decrease after AL-ST and was dependent on the dose in a statistically highly significant manner (p = 0.001). In addition to the well-known advantages of AL-ST, the following may be mentioned: 1. The intracavitary application was made without general anaesthesia, only with sedation by drugs, which prevented the primary treatment mortality. 2. An ambulatory treatment was possible in about 40% of the cases due to the time-sparing and patient-sparing method--the advantages are evident. 3. The therapeutic efficacy is increased and the risk of side effects in bladder and rectum is decreased by the better radiobiologic (same DR) and dosimetric adaption of AL-ST and percutaneous high-voltage therapy.