Introduction Oligometastatic disease is an intermediate state between locoregional disease and widely metastatic disease. Previous work by our group showed a significant difference between the median survival of uterine cancer patients with a single metastatic site versus multiple sites, hence we defined our oligometastatic cohort as having one metastatic site at diagnosis. In our current analysis we explore the trends of stereotactic body radiotherapy (SBRT) use in this oligometastatic population.

Methods The National Cancer Database was analyzed in patients diagnosed with uterine cancer between 2004–2019. We excluded patients with non-metastatic disease at diagnosis, lack of metastatic sites listed, multiple primaries and missing survival data. We included patients treated with radiotherapy and defined SBRT as ≤5 fractions and ≥500cGy dose per fraction.

Results Among 641,276 women with uterine cancer, 17,343 remained after exclusion and 12,214 had oligometastatic disease. 23.7% of metastatic patients received radiation (4.3% SBRT) and 22.0% of oligometastatic patients received radiation (3.2% SBRT). Among the oligometastatic SBRT cohort, patients received a median total dose of 21 Gy (range 800 cGy-67 Gy). SBRT sites include: brain (46.3%), uterus (11%), lung (9.8%), spine (8.5%), pelvis (7.3%), extremity bone (6.1%), other bone (4.8%), vagina (2.4%), liver (1.2%), lymph node (1.2%) and other (1.2%). SBRT patients had a median age of 63, low comorbidity index scores, and were high income earners.

Conclusion/Implications SBRT is underutilized in the treatment of uterine cancers, particularly in oligometastatic disease. Increasing the use of SBRT may have implications for increasing overall survival in oligometastatic uterine cancer.