Difficulty meeting patient accrual goals

This research study is designed to look at the effects of the combination of vorinostat (Suberoylanilide Hydroxamic Acid or Zolinza) and tamoxifen on breast cancer tissue. The investigators will do this by comparing tissues from the original breast biopsy to tissues obtained after taking vorinostat and tamoxifen for 2 weeks.

Key eligibility criteria include:

• Newly diagnosed invasive breast cancer awaiting surgery or neoadjuvant (preoperative) treatment
• No use of hormone contraceptives or replacement therapy within 30 days prior to the diagnostic breast cancer biopsy (unless willing to have an additional biopsy prior to starting the study)
• No prior or current use of any therapy to treat the current breast cancer.

Inclusion Criteria:

• Stage I-III invasive breast cancer
• Awaiting surgery or neoadjuvant treatment
• ECOG performance status 0, 1 or 2
• Adequate organ function
• Prior use of hormone contraception or replacement therapy must have been discontinued at least 30 days prior to diagnostic biopsy (unless participant is willing to undergo an additional biopsy for the study)

Exclusion Criteria:

• Prior or current treatment of any kind for the current breast cancer
• Current use of any other investigational drugs
• Uncontrolled or active infection, congestive heart failure, cardiac arrythmia, or psychiatric illness

14 days

Adverse events were assessed at baseline, after 14 days of study drug administration, and after the surgical procedure per CTCAE V. 4.0.

Unable to recruit participants to complete the study.