Radiation therapy for carcinoma of the uterine cervix: comparison of two brachytherapy schedules

We compared the survival rates and late effects for two groups of cervical cancer patients treated with almost the same external radiotherapy but different remote afterloading systems (RALS) for high-dose-rate intracavitary radiation therapy regimens. A total of 218 patients with carcinoma of the uterine cervix were treated. For 98 patients, intracavitary brachytherapy was delivered with 6-7.5 Gy/fraction to Point A (Group A), and for 120, 5 Gy/fraction with a modified source step size (Group B). The 3-year cause-specific survival rates by stage and treatment schedule were Group A: 91% and Group B: 96% in Stage I, 89% and 92% in Stage II, 64% and 75% in Stage III, 44% and 69% in Stage IV. The survival curves did not reveal any statistically significant differences at any stage. The 3-year cumulative local failure rates were 14% in Group A and 7% in Group B (P = 0.1202), while the actuarial rates of developing rectal complication (Grade 2 or more) at 3 years were 25% in Group A and 4% in Group B (P < 0.0001). This retrospective analysis suggests that a low dose per fraction with modified source step size is advantageous because of yielding almost the same local control but with fewer rectal complications.