Vitamin D and Breast Cancer: Does Weight Make a Difference?

This protocol is a randomized, controlled and blinded clinical trial in obese and non-obese subjects diagnosed with breast cancer in whom we will test the effects of vitamin D supplementation in the neoadjuvant setting and evaluate changes in biomarker expression in blood and tissue comparing core breast biopsy to definitive surgical samples. Our goal is to determine whether dietary vitamin D can reverse the negative effects of obesity and insulin resistance as reflected by favorable changes in the gene expression patterns in the pathologic specimens as well as in serum biomarkers of insulin resistance and adipokine secretion. We expect that vitamin D administration will improve the breast cancer gene expression pattern from a high-risk configuration to a low-risk profile in the obese patients and will also cause improvement in the non-obese.

• Drug: Vitamin D3
  Vitamin D 10,000 IU/day
  Other Name: cholecalciferol
• Drug: Vitamin D3
  Vitamin D 400 IU/day
  Other Name: cholecalciferol

• Experimental: Vitamin D3, Supportive care, A
  Vitamin D 10,000 IU/day
  Intervention: Drug: Vitamin D3
• Experimental: Vitamin D3, Supportive Care, B
  Vitamin D 400 IU/day
  Intervention: Drug: Vitamin D3

Inclusion Criteria:

• 3.1.1 Women who have undergone a core needle biopsy demonstrating an operable breast cancer whom have not yet had any further therapy.
• 3.1.2 No prior therapy for breast cancer.
• 3.1.4 Age 18 years or older.
• 3.1.5 Any menopausal status
• 3.1.6 Planned surgical resection of breast cancer or repeat core biopsy tissue sampling prior to initiation of neoadjuvant systemic chemotherapy.
• 3.1.7 Availability of tissue blocks from initial core needle biopsy.
• 3.1.8 Signed informed consent.
• 3.1.9 Willing to discontinue use of all supplements containing Vitamin D for the duration of the study, and take only the Vitamin D provided by the study.

Exclusion Criteria:

• 3.2.1 Presence of any Metastatic lesion.
• 3.2.2 History of parathyroid disease, hypercalcemia, or kidney stones.
• 3.2.3 History of SERM or aromatase inhibitor therapy.
• 3.2.4 Taking metformin.
• 3.2.5 History of renal failure requiring dialysis or kidney transplantation.
• 3.2.6 Women who are known to be pregnant or who are nursing. (As vitamin D does not have toxicity to the fetus, a negative pregnancy test is not a requirement to participate in the study.)
• 3.2.7 Patients planned for surgical therapy of their breast cancer or initiation of systemic chemotherapy, that would not allow for at least 7 days of vitamin D intervention
• 3.2.8 Patients with locally advanced breast cancer.
• 3.2.9 Any condition potentially interfering with subjects ability to comply with taking study medication.
• 3.2.10 Any medical condition that would potentially interfere with vitamin D absorption.
• 3.2.11 Current participation in another research study that would increase risk to subject, in the opinion of the investigators.
• 3.2.12 Patients currently taking more than 2000 IU of Vitamin D.