LAUSR

5583 Background: There is growing evidence that definitive local therapies (surgery or radiotherapy) may increase patient’s survival for some types of metastatic cancers. However, the role of total abdominal hysterectomy (TAH) for newly diagnosed uterine cancer with distant organ metastasis has not been established. The objective of this study is to determine the potential overall survival (OS) benefit associated with TAH for distant metastatic uterine cancer. Methods: The National Cancer Database was analyzed to evaluate OS for newly diagnosed uterine cancer patients with metastasis to brain, lung, liver, bone or distant lymph node, treated with chemotherapy with or without TAH. Those without treatment, treated with definitive pelvic radiotherapy, or without baseline variables were excluded. OS was analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards models, and propensity score-matched analyses. In order to control the selection biases, we performed Landmark analysis, and survival analysis by the sequence of chemotherapy and TAH. Separate survival analysis was performed for patients who received chemotherapy plus definitive pelvic radiotherapy (RT) or chemotherapy plus TAH and definitive pelvic RT. Results: From 2010 to 2014, 1,809 uterine cancer patients with distant organ metastasis received chemotherapy alone and 1,388 patients received chemotherapy plus TAH. At a median follow-up of 13.4 months, addition of TAH to chemotherapy was associated with improved survival on univariate (HR 0.57; P < 0.001) and multivariate analysis (HR 0.59; P < 0.001) compared to chemotherapy alone. Propensity score-matched analysis demonstrated superior median survival (19.8 vs 11.0 months) and 2-year OS (44% vs 28%) with TAH (multivariate HR 0.59; P < 0.001). Landmark analyses limited to long-term survivors of ≥0.5, ≥1, and ≥2 years showed improved OS with TAH in all subsets (all P < 0.05). The benefit of TAH was present among not only those involving one metastatic site (HR 0.59; P < 0.001), but also those involving multiple metastatic sites (HR 0.60; P < 0.001). Separate survival analyses showed chemotherapy plus definitive pelvic RT or chemotherapy plus TAH and RT were both superior to chemotherapy alone. Conclusions: In this large contemporary analysis, uterine cancer patients with distant organ metastasis receiving TAH and chemotherapy had substantial longer survival than patients treated with chemotherapy alone. Prospective trials evaluating TAH for metastatic uterine cancer are warranted.