Um estudo para ver se o estrogênio pode retardar o crescimento de alguns cânceres de mama ER positivos (PRESTO)

Inclusion Criteria:

• Female gender
• Estrogen receptor positive (ER+) breast cancer
• HER2 negative breast cancer
• Post-menopausal by greater than 5 years
• No previous hormonal replacement therapy
• Low to intermediate histologic grade
• ECOG Performance status of 0 of 1
• Adequate hematological, renal and hepatic function is required
• Ability to take oral medication
• Patient must have adequate tissue for diagnosis, biomarkers and Ki67 assays

Exclusion Criteria:

• Pre-menopausal women
• Locally advanced or metastatic breast cancer
• Current, previous or planning for pre-operative treatment with chemotherapy, hormone therapy including corticosteroids, radiation therapy for malignancy or other condition
• Known hypersensitivity or intolerance to estradiol
• Ischemic changes on baseline electrocardiogram
• Symptomatic but untreated cholelithiasis
• History of deep vein thrombosis, pulmonary embolism, stroke, acute myocardial infarction, congestive cardiac failure, untreated hypertension or known inherited hypercoagulable disorder
• Undiagnosed abnormal vaginal bleeding or prior history of endometrial cancer
• Untreated metabolic disturbances (glucose > 15.0 mmol/L and triglycerides > 400 mg/dL)
• Current treatment with drugs known to be moderate or strong inhibitors of inducers of isoenzyme CYP3A4
• The time between study enrolment and definitive breast surgery is not sufficient for administration of at least 7 days of estradiol