This research is a promising step toward a new, less invasive treatment choice for patients with specific genetic traits. It expands the range of care options for endometrial cancer. conditions: Endometrial Cancer Stage I conditions: Mmr Deficiency conditions: Endometrioid Endometrial Adenocarcinoma conditions: Immune-related Adverse Event studyType: INTERVENTIONAL phases: PHASE2 allocation: NA interventionModel: SINGLE_GROUP interventionModelDescription: This is a non-randomised, prospective, pilot, open-label, single arm study. Participation in this trial involves seven dostarlimab sessions over 12 months, with a treatment protocol of four cycles every three weeks, followed by a three-week break, and then three cycles every six weeks. primaryPurpose: TREATMENT masking: NONE count: 10 type: ESTIMATED name: Dostarlimab-Gxly 50 MG/1 ML Intravenous Solution [JEMPERLI] measure: Determine the absence endometrial cancer following protocol treatment regimen of dostarlimab. measure: Determine the safety and tolerability of dostarlimab in participants with early-stage MMR deficient endometrioid endometrial adenocarcinoma. measure: TEAEs/irAEIs Leading to Study Drug Discontinuation measure: TEAEs/irAEIs Leading to Study Withdrawal measure: Clinically Significant Changes in Haematology measure: Clinically Significant Changes in Clinical Chemistry measure: Clinically Significant Changes in Thyroid Function measure: Abnormal Vital Signs measure: Abnormal Electrocardiogram (ECG) Parameters measure: Clinically Significant Abnormal Physical Examination measure: Concomitant Medications measure: Study Feasibility Outcome: Recruitment Rate measure: Study Feasibility Outcome: Rationale for Treatment Discontinuation measure: Study Feasibility Outcome: Study Withdrawal Rate measure: Study Feasibility Outcome: Incidence of Immune-Related Adverse Events (irAEs) measure: Study Feasibility Outcome: Number of Cycles of dostarlimab Completed measure: Qualitative Evaluation by Semi-Structured Interview to gather valuable consumer feedback to inform future clinical research programs. measure: Participant Burden Assessment measure: Participant Burden Assessment - Adverse Events measure: Evaluation of Fertility Outcomes/Pregnancy Plans for WOCBP compare to their pre-treatment reproductive plans. measure: Correlate clinical efficacy (pCR) with irAEs. measure: Fertility outcome within the fertility preservation population - pregnancy rates measure: Fertility outcome within the fertility preservation population - pregnancy loss rates measure: Fertility outcome within the fertility preservation population - live birth rates measure: Fertility outcome within the fertility preservation population - rates of maternal and fetal complications/abnormalities sex: FEMALE minimumAge: 18 Years stdAges: ADULT stdAges: OLDER_ADULT facility: Westmead Hospital city: Sydney state: New South Wales zip: 2145 country: Australia name: Sara Baniahmadi role: CONTACT phone: 07 3346 5073 email: s.baniahmadi@uq.edu.au name: Alison Brand, Professor role: PRINCIPAL_INVESTIGATOR lat: -33.86785 lon: 151.20732 facility: Royal Brisbane and Women's Hospital city: Brisbane state: Queensland zip: 4029 country: Australia name: Sara Baniahmadi role: CONTACT phone: 07 3346 5073 email: s.baniahmadi@uq.edu.au name: Vanessa Behan role: CONTACT phone: 07 3346 5590 email: v.behan@uq.edu.au name: Jeffrey Goh, Associate Professor role: PRINCIPAL_INVESTIGATOR lat: -27.46794 lon: 153.02809 facility: Peter MacCallum Cancer Centre city: Melbourne state: Victoria zip: 3000 country: Australia name: Sara Baniahmadi role: CONTACT phone: 07 3346 5073 email: s.baniahmadi@uq.edu.au name: Linda Mileshkin, Professor role: PRINCIPAL_INVESTIGATOR lat: -37.814 lon: 144.96332 hasResults: False