Purpose: The current study was conducted to investigate the incidence and risk factors for medical complications associated with low dose rate brachytherapy in patients with medically inoperable Stage I endometrial cancer treated with irradiation alone.
Methods and materials: From 1965 through 1991 at Mallinckrodt Institute of Radiology, 150 implants were performed on 96 patients who were deemed medically unfit for hysterectomy because of advanced age, obesity, and various medical problems. The records of these patients were examined retrospectively to determine the incidence of medical complications that occurred in the first 30 days following the initiation of brachytherapy. The association of risk factors that precluded major surgery and the occurrence of brachytherapy-related complications was examined by logistic regression.
Results: Of these 96 patients, 40 patients were older than 75 years, and 31 patients were deemed morbidly obese. Medical problems included hypertension in 45 patients, and diabetes in 37; there was a history of congestive heart failure in 23, stroke in 11, myocardial infarction in 10, and thromboembolism in 8. There were concurrent malignancies in five patients. Implants were performed using intrauterine Simon-Heyman capsules, tandems, and vaginal ovoids in all patients. General anesthesia was used for 98 implants, spinal anesthesia for 26, local anesthesia for 25, and epidural anesthesia for 1. The duration of anesthesia ranged from 30 to 120 min (median, 60 min). The duration of radioisotope application ranged from 11 to 96 h (median, 46 h). Preventive measures included low dose subcutaneous heparin in 55 patients (since 1978), and intermittent pneumatic compression boots in 29 (since 1985). Four patients developed life-threatening complications including myocardial infarction (two patients), congestive heart failure (one patient), and pulmonary embolism (one patient). Two of these four patients died; one with a myocardial infarction and the other with pulmonary embolism. The morbidity rate was thus 4.2% (4 out of 96), and the mortality was 2.1% (2 out of 96). Although the four serious complications occurred within 30 days of the procedure, only one complication and one death occurred during treatment. There was no correlation between occurrence of complications and medical risk factors, type and duration of anesthesia, or type and duration of implant.
Conclusions: There is a low incidence of complications associated with conventional low dose rate brachytherapy. The procedure is well tolerated in patients with medically inoperable Stage I endometrial cancer. In comparison to the predicted serious complication rate of surgery in these patients, the number of life-threatening complications from brachytherapy appears to be quite acceptable.