Intracavitary irradiation of endometrial cancer of large uteri using a two-phase afterloading technique.

A specific intracavitary two-phase technique was developed for irradiation of endometrial cancer located in uteri with a large uterine cavity. In this technique an insertion catheter (external diameter 9 mm) was used for the introduction and precise location of the treatment catheter (external diameter 6.4 mm). During the first phase of the therapy, one lateral half of the uterine body was irradiated. Thereafter the positions of the catheters were changed by 180 degrees, followed by irradiation of the other lateral half of the uterine body. Using a wax phantom and extirpated uteri as models, we observed that the dose distributions followed the uterine shape and the calculated doses in the radiographs. Clinical observations from 34 patients treated so far, and followed-up for periods of 3 months to 6 years, prove that this method yields similar results to those observed in previous studies employing the Heyman packing method or afterloading techniques with a one-source tandem in the intracavitary irradiation of endometrial cancer.