F-18 16 Alpha-Fluoroestradiol-Labeled Positron Emission Tomography in Predicting Response to First-Line Hormone Therapy in Patients With Stage IV Breast Cancer

Inclusion Criteria

• •Patients will have pathologically confirmed invasive breast cancer with clinical, radiographic and/or pathologic evidence of stage IV disease; patients must have tissue blocks available from biopsy of at least one site of metastatic disease and/or from diagnosis of their primary breast cancer
• •Disease may be measurable (by Response Evaluation Criteria in Solid Tumors \[RECIST\] criteria) or non-measurable but must be present in at least one non-liver site and imageable on FDG PET scan; in patients with non-measurable disease by RECIST criteria, one of the following may be used to assess and follow disease: MUC-1 antigen level (either cancer antigen \[CA\] 27.29 or carcinoembryonic antigen \[CEA\]) \> 2 x upper limit of normal (ULN), Circulating tumor cell assay \> 5, or FDG-PET SUV \> 2.5 in purely lytic lesions; elevated tumor markers alone are insufficient
• •No prior endocrine therapy for breast cancer or
• •* Off adjuvant endocrine therapy for \> 6 months or
• •* Greater than 2 years of a single adjuvant endocrine therapy at the time of first recurrence and plan to change to alternate endocrine therapy; use of tamoxifen must be discontinued 6-8 weeks prior to entrance into the study
• •Prior chemotherapy regimens in the adjuvant or neoadjuvant setting are allowed
• •Women treated with adjuvant LHRH (luteinizing hormone-releasing hormone) analog are eligible
• •Be assessed for menopausal status; for study purposes, postmenopausal is defined as:
• •* A prior documented bilateral oophorectomy, or
• •* A history of at least 12 months without spontaneous menstrual bleeding, or
• •* Age 60 or older with a prior hysterectomy without oophorectomy, or
• •* Age less than 60 with a prior hysterectomy without oophorectomy (or in whom the status of the ovaries is unknown), with a documented follicle stimulating hormone (FSH) level demonstrating confirmatory elevation in the postmenopausal range for the lab
• •Premenopausal patients must have a baseline FSH, and estradiol levels to determine menopausal status; measures will be repeated at 3-6 months to confirm menopausal status
• •Patients must be positive for estrogen receptor (ER) and may or may not be positive for progesterone receptor (PgR) by IHC in the primary tumor and/or metastatic site; the pathology report for assay of ER will be reviewed by one of the investigators prior to enrollment, the study pathologist will review the pathology report if necessary for determination of study eligibility
• •Tumor HER2/neu expression must be determined prior to study enrollment; assessment may be by fluorescence in situ hybridization (FISH) assay or by immunohistochemistry (ICC); if determination is intermediate by ICC, FISH must be performed
• •Life expectancy \> 16 weeks
• •Eastern Cooperative Oncology Group (ECOG) performance status =\< 2 (Karnofsky \>= 60%)
• •Absolute neutrophil count (ANC) \>= 1,000
• •Platelet count \>= 50,000
• •Hemoglobin within normal limits (WNL) for the institution
• •Serum creatinine =\< 1.5 x institutional ULN (IULN) and estimated creatinine clearance \> 50 mL/min using the Cockroft-Gault formula
• •Bilirubin =\< 1.5 x ULN
• •Serum glutamic oxaloacetic transaminase (SGOT)/ serum glutamic pyruvate transaminase (SGPT) =\< 1.5 x ULN
• •Alkaline phosphatase =\< 2.5 x ULN
• •Patients must be planning a course of endocrine therapy with one of the following: tamoxifen +/- ovarian suppression, aromatase inhibitor +/- fulvestrant (with ovarian suppression in pre-menopausal patients) or fulvestrant alone
• •After entry into the study, patients are expected to be followed for at least 6 months after the injection of \[\^18F\] FES
• •Have a negative pregnancy test within 7 days prior to registration if of childbearing potential
• •No other prior malignancy is allowed except for the following: adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer, or any other cancer from which the patient has been disease-free for 5 years
• •Be informed of the investigational nature of this study and provide written informed consent in accordance with institutional and federal guidelines prior to study-specific screening procedures
• •Women of child-bearing potential must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation; should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately