Vaginal Brachytherapy Is Effective, has Fewer Side Effects, Gives Better Quality of Life

Vaginal brachytherapy is as effective as external beam radiation therapy in preventing the recurrence of higher-risk endometrial cancer but with fewer side effects and results in superior quality of life, according to a Phase 3 study presented by Remi A. Nout, MD.

As a result of the study, vaginal brachytherapy should be adopted as the new standard of care for patients with high-intermediate risk endometrial cancer, he said. The standard treatment has been surgery, followed by external beam radiation.

Vaginal brachytherapy is an outpatient treatment in which a radioactive cylinder is inserted into the vagina. It was compared with external-beam pelvic radiotherapy in 427 patients with high-intermediate risk endometrial cancer who were randomized to one of the two treatments after surgery. Previously, external-beam radiation therapy had been found to reduce the risk of vaginal and pelvic recurrence of stage 1 endometrial cancer from 19% to 5%, but without a survival benefit.

At a median follow-up of 36 months, vaginal recurrence rates were 1.9% with external-beam radiation therapy and 0.9% with vaginal brachytherapy, a nonsignificant difference (p =0.97).

The pelvic relapse rates were 3.6% with external beam radiation therapy and 0.7% with brachytherapy (p = 0.03).

There were no significant differences between vaginal brachytherapy and external-beam radiation in 3-year overall survival (90.4% vs. 90.8%) and recurrence-free survival (89.5% vs. 89.1%).

Quality-of-life measures favored brachytherapy. Moderate-to-severe diarrhea was reported by 22% of patients following completion of external-beam radiation therapy compared with 6% following vaginal brachytherapy (P %lt;0.001). As a result, the incidence of daily activities limited by bowel problems was significantly less in patients randomized to brachytherapy vs. external-beam radiation therapy (5% vs. 13%, respectively; P <0.001).

The incidence of diarrhea decreased over time, but at 2 years, 6% of the group assigned to external-beam radiation still reported moderate-to-severe diarrhea compared with only 1% assigned to vaginal brachytherapy.

"There was no significant difference in sexual activity level and sexual symptoms between the two treatments," said Dr. Nout, a resident in radiation oncology at Leiden University Medical Center, The Netherlands. All age groups showed an increase in sexual functioning after either therapy, except for women in the the oldest age group (>75 years).