CHICAGO, June 1 -- Vaginal brachytherapy is as effective in preventing a recurrence of endometrial cancer after surgery in women with high-intermediate risk disease as external-beam pelvic radiotherapy but with less GI toxicity, Dutch researchers reported here.
Vaginal brachytherapy did not extend overall or progression-free survival compared with pelvic radiotherapy, but 22% of external- beam patients developed severe diarrhea versus 6% of the vaginal brachytherapy patients, Remi A. Nout, M.D., of Leiden University reported at the American Society of Clinical Oncology meeting here.
Action Points
- Explain to interested patients that this report suggests that gastrointestinal toxicity is less with vaginal brachytherapy than with external beam radiation.
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
After two years, 6% of women randomized to adjuvant external- beam radiation had moderate to severe diarrhea, versus 1% of the vaginal brachytherapy patients.
During treatment, 35% of the external-beam pelvic radiotherapy patients reported diarrhea or cramping versus 12% of brachytherapy patients.
An earlier study that compared external beam radiation to observation following surgery, found that that there was a significantly higher rate of local recurrence among patients who did not have adjuvant radiation.
In the current PORTEC-2 trial, 214 patients were randomized to pelvic external-beam radiotherapy and 213 to vaginal brachytherapy.
The external-beam pelvic radiation therapy dose was 43 Gy in 23 fractions and the brachytherapy dose was 21 Gy (high dose rate) in three fractions or 30 Gy (low dose rate). Patients were 60 or older with surgically resected endometrial cancer and a high to intermediate risk of relapse.
After three years, the rate of pelvic relapse was 3.6% in the vaginal brachytherapy arm versus 0.7% for external-beam pelvic radiation (P =0.03).
The three-year actuarial rate of vaginal relapse, pelvic, and distant relapse were 0%, 1.3%, and 6.4% in the vaginal brachythereapy group versus 1.6%, 0.7%, 6.0% in the external beam pelvic radiotherapy group (NS).
The three-year overall survival was 90.4% versus 90.8% in the external-beam radiotherapy group, (P =0.55).
Dr. Nout said the most significant benefit for vaginal brachytherapy was a reduction in diarrhea, which was associated with "a moderate to severe reduction in activities of daily living."
He said, however, that brachytherapy was not associated with an increase in vaginal stenosis, a severe adverse effect that has been noted by other researchers. He said there was no "adverse effect on sexual activity," except among women 75 or older. In general, he said, those women were not sexually active prior to treatment.
For women who were sexually active, vaginal brachytherapy improved sexual function, he said.
On the basis of these results, Dr. Nout said "vaginal brachytherapy should be the treatment of choice for patients with high-intermediate risk cancer."
| Dr. Nout said he had nothing to disclose, and the study was institutionally funded. |