Study of Vitamin D for Premenopausal Women at High Risk for Breast Cancer
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Intervention: Cholecalciferol
Intervention description: Cholecalciferol is a vitamin D3. Vitamin D is important for the absorption of calcium from the stomach and for the functioning of calcium in the body. Cholecalciferol is used to treat or prevent many conditions caused by a lack of vitamin D.
Cholecalciferol will be available in gel capsule form at 10,000 IU (0.25 mg cholecalciferol) each.
Intervention MeSH terms: Vitamin D; Cholecalciferol
Phase: Phase 1
Study type: Interventional
Primary purpose: Prevention
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 20.0
Sex: Female
Minimum age: 21 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: Breast cancer; Vitamin D; Premenopausal

Summary:

      This proposal is for a pilot study of 20 premenopausal women at high risk for breast cancer
      development who will receive high dose vitamin D3, cholecalciferol 20,000 IU (2 capsules)
      weekly, or 30,000 IU (3 capsules) weekly, for 1 year. The primary objective of this study is
      to determine the feasibility of a 1-year intervention of vitamin D in this study population.
      Secondary objectives include evaluating the biologic effects of vitamin D supplementation on
      blood based and image-based biomarkers.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Elevated risk of breast cancer defined as having at least one of the following: (1)
             Predicted 5-year modified Gail model risk of 1.7% or greater, (2) Lobular carcinoma in
             situ, (3) Known BRCA1 or BRCA2 deleterious mutation carrier, (4) Prior history of
             ductal carcinoma in situ, if no current tamoxifen use or prior radiation to the
             contralateral breast.

          -  Age 21 years or older.

          -  Premenopausal defined as < 6 months since the last menstrual period, no prior
             bilateral oophorectomy, not on estrogen replacement, and serum Follicle-stimulating
             hormone (FSH) values consistent with institutional normal values for the premenopausal
             state.

          -  Normal breast exam and mammogram (BIRADS score of 1 or 2).

          -  Baseline mammographic density ≥25% as assessed qualitatively by the mammographer
             (25-50% = "scattered fibroglandular densities"; >50-75% = "heterogeneously dense
             breasts"; >75% = "extremely dense breasts").

          -  Baseline serum 25-hydroxyvitamin D <32 ng/ml.

          -  Prior tamoxifen use is allowed provided treatment is discontinued at least 28 days
             prior to enrollment.

          -  Willingness to allow submission of core needle breast biopsy for pathology review and
             collection of blood for biomarker analysis and banking.

          -  At least one breast available for imaging and biopsy.

          -  Willingness to not take calcium or vitamin D supplements during the one year
             intervention, due to the potential risk of hypercalcemia/hypercalciuria with high dose
             vitamin D. Premenopausal women who need to take calcium supplementation for any
             medical condition will be excluded from the study. Dietary restrictions on calcium
             intake may be imposed if the subject is found to have borderline high serum or urine
             levels of calcium during the study intervention and a list of dietary sources of
             calcium will be provided.

          -  Normal serum calcium.

          -  No history of kidney stones.

          -  Adequate renal and hepatic function: serum creatinine, bilirubin, aspartate
             aminotransferase (AST), alanine transaminase (ALT) and alkaline phosphatase < 2.0 x
             the institutional upper limit of normal (IULN).

          -  No hypersensitivity reactions to vitamin D.

          -  Performance status of 0 or 1.

          -  Not pregnant or nursing.

          -  Agree to use effective contraception, hormone-based oral contraceptives allowed but
             switching birth control methods is discouraged while on-study.

          -  No significant medical or psychiatric condition that would preclude study completion.

        Exclusion Criteria:

          -  Not meeting one or any of inclusion criteria