Clinical Outcomes of Post-Operative Endometrial Cancer Patients Treated with Vaginal Brachytherapy Alone

Purpose/Objective: To assess the clinical outcomes of post-operative endometrial cancer patients undergoing adjuvant vaginal brachytherapy (VBT).Materials and Methods: The records of all endometrial cancer patients treated with adjuvant VBT alone following total abdominal hysterectomy and bilateral saphingo-oophorectomy (TAH/BSO) at our institution between 2006 and 2010 were retrospectively reviewed. VBT was delivered with vaginal cylinders using high-dose-rate (HDR) iridium-192 radiation. All relevant clinical and brachytherapy plan dosimetric data were collected. For the purpose of this study, patients were restaged according to FIGO 2009 classification. Any short-term or long-term treatment related toxicity, as well as the incidence of local, regional, and distant failure was recorded.Results: A total of forty-five patients were examined. The median age was 67 years (range 37 - 86). Median follow-up from the date of the last VBT fraction was 39.2 months (range 6.1 - 83.0). All patients but one received 22 Gy in 4 fx prescribed to 0.5 cm depth (one patient received 21 Gy in 3 fx). Thirty-six percent of patients received concurrent chemotherapy (most frequently with carboplatin and taxol). The number of stage IA, IB, II, and IIIA patients were 20, 13, 11, and 1, respectively. Twenty-nine had endometrioid-type adenocarcinoma (64.4%), 12 were papillary serous (26.7%), 3 were clear cell (6.7%), and 1 was a mixed mesenchymal tumor (2.2%). The median cylinder apex point dose, as a percentage of total prescription dose, was 100% (range 80 - 130%). The median treatment length was 3.1 cm (range 1.5 - 5.0 cm). Treatment was well tolerated as no patients experienced any on-treatment or long-term toxicity (fatigue, GI, GU, or skin) greater than grade 1. Two patients failed locally (1 adenocarcinoma, 1 clear cell), 5 patients failed regionally (1 adenocarcinoma, 4 papillary serous), and the mixed mesenchymal tumor patient failed distally. Median time to recurrence was 12.2 months from the date of the last VBT fraction (range 3.9 - 41.2). One local failure occurred at the vaginal cuff (adenocarcinoma, grade 2, stage IA) while the other occurred in the vagina location NOS (clear cell, grade 3, stage IA). Of the four papillary serous regional recurrences, 2 were stage IA, 1 was stage IB, and 1 was stage II; all 4 patients received concurrent chemotherapy.Conclusion: Satisfactory local control (96%) was achieved in our patient population with minimal toxicity. Since most of our regional failures were of papillary serous histology, consideration should be given to pelvic nodal irradiation in addition to, or in lieu of, VBT in this particular subset of patients.

MSRO35-09

Clinical Outcomes of Post-Operative Endometrial Cancer Patients Treated with Vaginal Brachytherapy Alone