This clinical trial is focused on studying a type of cancer called endometrial cancer, which affects the lining of the uterus. Specifically, the trial is looking at a subtype known as mismatch-repair deficient high-risk endometrial cancer (MMRd HREC). This subtype is characterized by certain genetic features that make it more aggressive. The treatment being tested in this study is a medication called durvalumab, also known by its code name MEDI4736. Durvalumab is given as an infusion, which means it is administered directly into the bloodstream through a vein.

The purpose of the study is to see if this treatment can help prevent the cancer from coming back after surgery. Participants in the study will receive durvalumab infusions and will be monitored over a period of time to check for any signs of cancer recurrence. The study aims to follow patients for up to three years to assess how well the treatment works in keeping the cancer from returning.

Throughout the study, participants will have regular check-ups and tests to monitor their health and the status of their cancer. These tests may include imaging scans like MRI or CT scans, which help doctors see inside the body. The study will also look at the overall health and quality of life of participants, as well as any side effects they may experience from the treatment. The goal is to gather information that could lead to better treatment options for people with this type of endometrial cancer in the future.