Safety and Efficacy of Retifanlimab (INCMGA00012) Alone or in Combination With Other Therapies in Participants With Advanced or Metastatic Endometrial Cancer Who Have Progressed on or After Platinum-based Chemotherapy.

Inclusion Criteria:

* Ability to comprehend and willingness to sign a written ICF for the study. Note for Germany: This excludes individuals who are housed in an institution due to official or court order Women 18 years of age or older (or as applicable per local country requirements).
* Histologically confirmed diagnosis of advanced or metastatic endometrial cancer with disease progression on or after treatment with at least 1 platinum-containing regimen for advanced or metastatic disease.
* Groups A, B, and E: Have not been previously treated with a PD-(L)1 inhibitor.
* Group A only: Tumor tissue tested as MSI-High
* Group B only: Tumor tissue tested as deficient MMR or an ultra-mutated POLE tumor.
* Group D only: Tumor tissue tested as having an FGFR 1,2,3 mutation or alteration characterized as per protocol.
* Group E: Tumor tissue tested as MSS and PD-L1 positive.
* Group F: Radiological evidence of disease progression on or after prior PD (L)1 therapy and Tumor tissue tested as MSI-H
* Must have at least 1 measurable tumor lesion per RECIST v1.1.
* Willing to provide tumor tissue sample (fresh or archived).
* ECOG performance status 0 to 1.
* Willingness to avoid pregnancy.

Exclusion Criteria:

* Group A, B and E only: Histologically confirmed diagnosis of carcinosarcoma of the uterus.
* Histologically confirmed diagnosis of sarcoma of the uterus.
* Has disease eligible for potentially curative treatment.
* Receipt of anticancer therapy within 28 days of the first administration of study treatment, with the exception of localized radiotherapy.
* Toxicity of prior therapy that has not recovered to ≤ Grade 1 or baseline unless approved by the medical monitor.
* Groups C, D and F (combinations): limiting immune-related toxicity during prior checkpoint inhibitor therapy.
* Group F only: Previous treatment with LAG-# or TIM-3 therapy or lenvatinib; multiple metastases that achieved mixed tumor response to prior anti-PD-(L)1 therapy
* Has an active autoimmune disease requiring systemic immunosuppression with corticosteroids (\> 10 mg/day of prednisone or equivalent) or immunosuppressive drugs within 14 days before the first dose of study treatment.
* Receiving chronic systemic steroids (\> 10 mg/day of prednisone or equivalent):
* Known active CNS metastases and/or carcinomatous meningitis.
* Has known active hepatitis B or C.
* Has received a live vaccine within 28 days of the planned start of study treatment.
* Evidence of interstitial lung disease or active, noninfectious pneumonitis.
* Participants who are known to be HIV-positive with some protocol exceptions.