Treatment patterns and real-world clinical outcomes in patients with advanced endometrial cancer that are non-microsatellite instability high (non-MSI-high) or mismatch repair proficient (pMMR) in the United States

•First study to describe real-world outcomes in non-MSI-H/pMMR aEC patients who progressed following prior systemic therapy.•MSI/MMR testing was near universal in aEC patients in the US, reflecting the increased awareness of biomarker status.•Patients on second-line chemo or hormonal therapy had poor clinical outcomes: median OS of 10 months and rwPFS of 5 months.•Data suggest an unmet medical need in this population between 2016 and 2019.