High-dose rate and low-dose rate intracavitary therapy for carcinoma of the uterine cervix. Final results of Osaka University Hospital.

BACKGROUND: High-dose rate (HDR) intracavitary radiation therapy for carcinoma of the uterine cervix has gradually found wider acceptance. In 1983, the authors first presented the results of prospective randomized comparative study of HDR versus low-dose rate (LDR) therapy. In the current study, the final results of this study with a longer follow-up are presented.

METHODS: From January 1975 through August 1983, 430 previously untreated patients with carcinoma of the uterine cervix in Stages I-III were treated with either HDR 60Co therapy or LDR 137Cs therapy at our department. HDR was administered to a total of 259 patients: 32 patients in Stage I, 80 in Stage II, and 147 in Stage III. LDR was administered to a total of 171 patients: 28 patients in Stage I, 61 in Stage II, and 82 in Stage III.

RESULTS: The 5-year cause-specific survival rates of Stage I-III patients treated with HDR were 85%, 73%, and 53%, respectively. The corresponding figures for LDR were 93%, 78%, and 47%, respectively. There was no significant difference between these survival rates. Moderate-to-severe complications developed in 10% of the patients treated with HDR and 4% of those with LDR. This difference in the incidence of complications was statistically significant (P = 0.023).

CONCLUSIONS: Treatment results in terms of cause-specific survival were equivalent for HDR and LDR treatment. However, the incidence of complications was higher for the HDR group, although within acceptable levels, than for the LDR group.