We want to learn if Targretin has any effect on these markers in breast tissue.

Breast cancer is the most common malignant disease in women of the Western world. In the U.S. more than 200,000 women will be diagnosed with breast cancer in the next year, and more than a third of these will eventually die of the disease. Particularly worrisome is the dramatically increasing incidence of this disease in the past ten years, which all cannot be attributed to the early detection bias due to increasing use of screening mammography. Now, one in nine women born in this country will be diagnosed with breast cancer during her lifetime. Although new systemic treatments for established breast cancer may be reducing mortality somewhat major breakthroughs have come slowly, and greater attention is now being directed toward means of breast cancer prevention.

Epidemiologic studies have identified risk factors that are associated with an increased risk of developing breast cancer. These include Western culture and obesity (providing a link to dietary fat), family history, hormonal factors such as age at menarche or menopause (ovariectomy before age 45 is protective), age at first full-term pregnancy, prolonged oral contraceptive or postmenopausal estrogen use, exposure to radiation, benign breast disease, and a history of previous breast biopsy. Of these, family history is perhaps the strongest risk factor. It has long been known that breast cancer is in part a hereditary disease, and that approximately 3-5% of breast cancer is due to strongly penetrant, single gene inheritance. Over the past several years, a number of these genes have been cloned including BRCA-1, BRCA-2, p53, and PTEN, the gene responsible for Cowden's disease. Of these genes, BRCA-1 and BRCA- 2 are estimated together to be involved in 60 to 70% of all hereditary breast cancer. Persons with these mutations have an approximate 50 to 80% lifetime risk of developing breast cancer, and currently there are no preventive options except for surgical mastectomy. It is therefore a high priority to identify new agents which might be able to lower this very high risk.

In this study a dose of bexarotene (Targretin capsules) 200 mg/m2/day for 28 days was selected for a number of reasons. Limiting exposure to 28 days would minimize risk to study participants, while allowing enough time for relevant changes in biomarkers to occur. 300 mg/m2/day has been shown to be biologically active and therapeutic against cutaneous T-cell lymphoma in humans. To increase safety while maintaining potential activity in normal breast tissue, a dose of 200 mg/m2/day was chosen.

The anti-tumor action of retinoids, as well as their potential in chemoprevention, supports the need to further identify the spectrum of responsive tumors, to identify the molecular mechanisms associated with retinoid action, and to identify and develop new retinoids that have unique properties and an improved therapeutic index.

• Drug: Targretin
• Drug: tagretin

Inclusion Criteria:

• Age > 18 years 2. All subjects must be female 3. Signed informed consent 4. >/- 10% risk of carrying a BRCA-1 or BRCA-2 mutation. Risk will be estimated using the probability models developed by Parmigiana, Couch, Myriad I, or Myriad II. The latter three models require an affected proband; therefore, either the subject or a close relative (the closest, youngest affected relative) can be used as the proband for the purposes of calculating risk. If a relative is used as a substitute proband, the subject's risk is estimated as the model risk for the relative, divided by 2 raised to the power of the degree of relatedness. For example, suppose the subject's mother, a first-degree relative, is her closest, youngest affected relative, and the Couch estimate of risk for the mother is 16.2%. The subject's risk will be half of her mother's [16.1/(2(1)) = 8.1%] and she would not be eligible. The risk for the subject must be >/- 10%. Known mutation carriers are eligible regardless of their calculated probability. A copy of a laboratory report stating results for known carriers must be available for review as a source document. 5. If subjects are of reproductive potential, they must be using a reliable contraceptive method or be sexually abstinent. Reliable methods include tubal ligation, IUD, oral contraceptives, the combination of spermicide and condom, or cervical cap and spermicide. Subjects must fulfill these conditions beginning one month before beginning study medications and ending one month after study termination. 6. Negative serum pregnancy test (bHCG) done within one month of Day 1 and on Day 1 before study medication is taken. 7. Adequate renal function, defined by serum creatinine within 1.5 times the institution's upper limit of normal. 8. Adequate liver function, defined by total bilirubin, SGOT, alkaline phosphatase and albumin, within 1.5 times the institutions upper limits of normal. 9. Adequate bone marrow function, defined as a WBC > 4.0, a platelet count > 100,000 and a hematocrit of >30. 10. Normal triglycerides for the institution. 11. Normal TSH, T4. Patients on thyroid hormone supplementation are eligible. 12. Have at least one breast that has never been involved with cancer and has not been irradiated. 13. Willing to undergo 2 duplicate needle biopsies of the breast. 14. Willing to have genetic testing for BRCA-1 and BRCA-2 mutations for research purposes. Results will only be disclosed upon request of the participant.

Exclusion Criteria:

• Exclusion criteria: 1. Pregnancy, lactation or unwillingness to use a reliable contraceptive method in women of childbearing potential. 2. Abnormal triglycerides, greater than the institutional upper limit of normal. 3. Severe underlying chronic illness or disease, such as uncontrolled diabetes. 4. Invasive cancer within the last 1 year, defined from the date of first diagnosis. 5. Current alcohol use >3 drinks/day. 6. History of pancreatitis. 7. Oral Vitamin A supplements greater than the recommended daily requirement (5,000IU), therapeutic oral or topical Vitamin A derivatives such as Accutane in the past 3 months prior to Day 1. 8. Tamoxifen or other SERM use in the past 3 months prior to Day 1. 9. Postmenopausal hormone therapy use, including estrogens or progestins in the past 3 months prior to Day 1. 10. Chemotherapy for a neoplasm in the past 1 year. 11. Currently participating in a study of an investigational agent. 12. Unwillingness to have BRCA-1 and BRCA-2 genetic testing for research purposes. 13. Medications known to be associated with pancreatic toxicity or to increase triglyceride levels. 14. Biliary tract disease. 15. Uncontrolled hyperlipidemia. 16. Non-toxic goiter or thyroid enlargement.