Adjuvant vaginal brachytherapy and chemotherapy versus pelvic radiotherapy in early-stage endometrial cancer: Outcomes by risk factors

To report on patterns of care as well as evaluate the two treatment regimens using a large retrospective hospital-based registry to identify possible subgroups of patients who may experience benefit with VBT + CT vs. EBRT. Patients from the National Cancer Database (NCDB) were identified who met the inclusion criteria for GOG 249 and were treated with either VBT + CT or WPRT. Demographic, clinicopathologic, and treatment factors were collected. Association of treatment type and other variables with overall survival was analyzed using Cox proportional hazards model. Subset analyses were performed based on a variety of risk factors, including high risk pathologies, surgical nodal sampling, and grade. A total of 4,602 patients were included in the analysis, with 41% receiving VBT + CT and 59% receiving WPRT. For the entire cohort, VBT + CT was associated with improved survival, with 3-year overall survival 89.6% vs. 87.8% (hazard ratio 1.24, 95%CI 1.01–1.52, p = 0.04). On subset analysis, patients with serous histology experienced benefit with VBT + CT, while high-grade endometrial patients without lymph node dissection experienced improved survival associated with EBRT. After exclusion of serous histology, there was no survival difference associated with treatment type. VBT + CT was associated with superior survival outcomes in patients with early-stage serous carcinoma. For non-serous histology, treatment modality was not associated with a difference in survival, although patients with high-grade disease and no nodal dissection experienced benefit from EBRT. •The NCDB was reviewed to compare treatments for various subgroups of patients with endometrial cancer.•The addition of chemotherapy results in an improved survival for serous histology but not for other subgroups.•Certain constellations of risk factors appear to benefit from external beam radiotherapy.