Patterns of care and outcomes of radiotherapy or hormone therapy in patients with medically inoperable endometrial adenocarcinoma.

Objective: The optimal treatment for medically inoperable endometrioid endometrial adenocarcinoma is unknown. The goal of this study was to evaluate the patterns of care and efficacy of radiotherapy (RT) or hormone therapy (HT) in the treatment of these patients.

Methods: We performed a query of the National Cancer Database (NCDB) of patients with medically inoperable endometrioid adenocarcinoma of the endometrium diagnosed between 2004 and 2016 and treated with either RT or HT. A multivariate Cox regression model and propensity weighted analyses were used to evaluate overall survival after controlling for confounding variables. A multinomial logistic regression model was used to assess predictors of RT or HT use.

Results: A total of 1036 patients were included in this cohort, and 73% (n = 759) were treated with RT alone. Patients who received definitive HT compared to RT were more likely to be older, diagnosed in the earlier years of this analysis, treated at lower-case volume centers, diagnosed with high-grade disease, or located outside of metropolitan areas. On multivariate analysis, treatment with HT alone versus RT alone was associated with significantly worse overall survival in the multivariate Cox model but not on propensity score weighted analysis. Interaction effect testing revealed that older patients and those treated at lower-volume centers had improved survival with RT compared to HT.

Conclusions: We identified factors associated with the receipt of RT or HT in medically inoperable endometrial cancer patients. Treatment with RT correlated with improved survival compared to HT in older patients and those treated at lower-volume centers.