Megestrol Acetate With or Without Pterostilbene in Treating Patients With Endometrial Cancer Undergoing Hysterectomy

Prior treatment

• Pterostilbene supplements within 30 days prior to day 1 of protocol therapy
• Any of the following phytochemical-based supplements within 30 days prior to day 1 of protocol therapy: resveratrol, genistein, and quercetin
• Chemotherapy for EC

Other illness

• Allergic reaction/hypersensitivity to similar agents, excipients
• Unstable cardiac disease as defined by one of the following:
  • Cardiac events such as myocardial infarction (MI) within the past 6 months
  • NYHA (New York Heart Association) heart failure class III-IV
  • Uncontrolled atrial fibrillation or hypertensive emergency/urgency (defined as systolic blood pressure \>= 180 mmHg and/or diastolic blood pressure \>= 120 mmHg)
• Active or history of recent thromboembolism or stroke, within the past 6 months
• Cushing's syndrome
• Acute infection requiring systemic (intravenous) treatment
• Known history of human immunodeficiency virus (HIV) infection
• Known active hepatitis B or C infection
• Any other condition that would, in the investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns or compliance with clinical study procedures, e.g., infection/inflammation, intestinal obstruction, unable to swallow medication, social/ psychological issues, etc

Other

• Inability to swallow tablets/capsules
• Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)

• Documented informed consent of the participant and/or legally authorized representative
• Willing to undergo an intraoperative biopsy/or standard of care tissue collection during surgery, following completion of treatment with MA +/- PTE
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• Histologically confirmed EC or complex atypical hyperplasia of the endometrium
• Candidate for a total hysterectomy with or without bilateral salpingo-oophorectomy
• About to initiate preoperative window period, with planned hysterectomy scheduled
• Platelets \>= 100,000/mm\^3
  • NOTE: Platelet transfusions are not permitted within 14 days of platelet assessment unless cytopenia is secondary to disease involvement
• Total bilirubin =\< 1.5 X upper limit of normal (ULN)
• Aspartate aminotransferase (AST) =\< 1.5 x ULN
• Alanine aminotransferase (ALT) =\< 1.5 x ULN
• Creatinine clearance of \>= 60 mL/min per 24 hour urine test or the Cockcroft-Gault formula
• Women of childbearing potential: negative urine or serum pregnancy test in premenopausal women. Postmenopausal women do not need to undergo a pregnancy test. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required