Hyperfractionation in carcinoma of the cervix: tumor control and late bowel complications

Hyperfractionation has been advocated to improve local tumor control by increasing radiation dose without increasing late normal tissue complications. The aim of this study was to determine if hyperfractionation decreased late bowel complications.

Thirty patients with Stage II and III cervical cancer were randomized to receive either hyperfractionation or conventional fractionation. Patients were followed for 5 years and monitored for tumor control, recurrence, and bowel complications. The relative risks of tumor control and bowel complications were computed at 1 year and 5 years of follow-up. Kaplan-Meier survival curves were plotted to determine probabilities of being tumor-free and bowel complication-free.

There were 15 patients in each group. At 1 year of follow-up, 2 patients in the hyperfractionation group (13%) and 7 patients in the conventional treatment group (45%) had tumor (relative risk [RR] 0.3; 95% confidence interval [CI] 0.1, 1.1; p = 0.054). Delayed bowel complications were seen in 8 patients in the hyperfractionation group and 1 patient in the conventional treatment group (RR 7.5; 95% CI 1.1, 52; p = 0.014). At 5 years, 2 patients in the hyperfractionation group and 8 patients in the conventional treatment group had tumor (RR 0.3; 95% CI 0.1, 1.1; p = 0.04). Delayed bowel complications (Grades 2 and 3) occurred in 9 women in the hyperfractionation group and 2 patients in the conventional group (RR 5.4; 95% CI 1.5, 19.5; p = 0.0006). Kaplan-Meier analysis showed that the hyperfractionation group had significantly more bowel complications over the 5 years of follow-up (p = 0.024).

Hyperfractionation may result in better tumor control both at 1 year and at 5 years following treatment of cervical cancer. However, hyperfractionation could lead to increased late bowel complications and must be used judiciously in the treatment of cervical cancer.