[Postoperative irradiation of carcinoma of the corpus uteri using the iridium afterloading technic]

From 1981 to 1986 a prospective study was conducted of University of Vienna, 1st gynecology department, for 708 patients with operated and postoperatively irradiated endometrial cancer. These patients were treated by total hysterectomy, bilateral salpingo-oophorectomy and postoperative vaginal irradiation with high-dose-afterloading (iridium 192). A percutaneous irradiation (cobalt 60) was done in stage I cases only when myometrial infiltration was deep. Highly differentiated tumors with infiltration of the first and second third of the myometrium were treated by vaginal irradiation alone. Poorly differentiated tumors (G2, G3) with infiltration of the second and third third of the myometrium were treated by vaginal and percutaneous irradiation. A group of 125 cases with good prognosis (infiltration 1/3, G1) and with postoperative vaginal irradiation alone had the same five-year-survival of 83% as a group of 152 cases with bad prognosis (infiltration 2/3 and 3/3, G2 or G3) treated by vaginal and percutaneous irradiation. This result shows clearly the importance of additional irradiation of the pelvis in cases with bad prognosis factors. The incidence of radiation side effect in all 708 cases was: cystitis 4.6%, proctitis 5.2%, vaginal or rectal ulcers 1.4% and fistulas 0.2%. Cases with vaginal irradiation alone and with the optimal intravaginal fraction dose of 700 cGy (twice) had the lowest level of side effects: cystitis 3.8%, proctitis 2.1%, vaginal necrosis 0.7%, no further severe complications. None of the patients with postoperative vaginal irradiation alone had a vaginal recurrence. The incidence of recurrences in 708 patients was 1.6%. All recurrence cases in stage I (0.7%) had bad prognosis factors and were treated with vaginal and percutaneous irradiation. It is concluded that primary surgery of endometrial cancer should be followed by postoperative vaginal radiation. It appears that the remote afterloading treatment for vaginal radiation produces minimally complications and gives complete protection from radiation exposure to the medical staff. With additional external radiation in high-risk cases the same good result can be achieved as in cases with low-risk and vaginal radiation alone.