ABSTRACT
BACKGROUND: This retrospective, multicenter study evaluated the feasibility and safety of high-dose rate electronic brachytherapy (EBT) as a postsurgical adjuvant radiation therapy for endometrial cancer. METHODS: Medical records were reviewed from 41 patients (age 40-89 years) with endometrial cancer (Federation of International Gynecology and Obstetrics stages IA-IIIC) treated at nine centers between April 2008 and October 2009. Treatment included intracavitary vaginal EBT alone (n = l6) at doses of 18.0-24.0 Gy in 3-4 fractions and EBT in combination with external beam radiation therapy (EBRT, n = 25) at a total radiation dose range of 40.0-80.4 Gy. Doses were prescribed to a depth of 5 mm from the applicator surface and to the upper third (n = 15) and the upper half (n = 26) of the vagina. RESULTS: Median follow-up was 3.8 (range 0.5-12.0) months. All 41 patients received the intended dose of radiation as prescribed. Adverse events occurred in 13 of 41 patients and were mild to moderate (Grade 1-2), consisting primarily of vaginal mucositis, rectal mucosal irritation and discomfort, and temporary dysuria and diarrhea. There were no Grade 3 adverse events in the EBT-only treatment group. One patient, who was being treated with the combination of EBT and EBRT for recurrent endometrial cancer, had a Grade 3 adverse event. No recurrences have been reported to date. CONCLUSION: Electronic brachytherapy provides a feasible treatment option for postoperative adjuvant vaginal brachytherapy as sole radiation therapy and in combination with EBRT for primary endometrial cancer. Early and late toxicities were mild to moderate.
ABSTRACT
BACKGROUND: A modified form of high dose rate (HDR) brachytherapy has been developed called Axxent Electronic Brachytherapy (EBT). EBT uses a kilovolt X-ray source and does not require treatment in a shielded vault or a HDR afterloader unit. A multi-center clinical study was carried out to evaluate the success of treatment delivery, safety and toxicity of EBT in patients with endometrial cancer. METHODS: A total of 15 patients with stage I or II endometrial cancer were enrolled at 5 sites. Patients were treated with vaginal EBT alone or in combination with external beam radiation. RESULTS: The prescribed doses of EBT were successfully delivered in all 15 patients. From the first fraction through 3 months follow-up, there were 4 CTC Grade 1 adverse events and 2 CTC Grade II adverse events reported that were EBT related. The mild events reported were dysuria, vaginal dryness, mucosal atrophy, and rectal bleeding. The moderate treatment related adverse events included dysuria, and vaginal pain. No Grade III or IV adverse events were reported. The EBT system performed well and was associated with limited acute toxicities. CONCLUSIONS: EBT shows acute results similar to HDR brachytherapy. Additional research is needed to further assess the clinical efficacy and safety of EBT in the treatment of endometrial cancer.
