Broccoli Sprout Extract in Treating Patients With Breast Cancer

Inclusion Criteria:

* Postmenopausal (no menstrual cycle in the past 12 months)
* Diagnosed with incident, primary, invasive, ductal or lobular, or other epithelial malignancy, clinical stage I or II, ER positive or negative breast cancer, or ductal carcinoma in situ (DCIS)
* No neoadjuvant endocrine therapy or chemotherapy within 12 months
* Have an Eastern Cooperative Oncology Group (ECOG) performance status of =\< 2
* Willing to avoid cruciferous vegetable intake during the study period (2 weeks)
* Demonstrate the ability to swallow and retain oral medication
* Subject or legal representative must understand the investigational nature of this study and sign an Independent Ethics Committee/Institutional Review Board approved written informed consent form prior to receiving any study related procedure

Exclusion Criteria:

* Prior invasive breast cancer, prior mastectomy or breast radiation within 12 months
* Current or recent use of reproductive hormone therapy, tamoxifen, aromatase inhibitor or other estrogen inhibitors within the last 90 days, which may affect biomarkers
* Intolerance to broccoli/ITC-BSE taste
* Current ingestion of broccoli sprout extract, which may confound study results
* Current or recent treatment for any malignancy within the last one year, which may affect biomarkers
* History of Crohn's disease, celiac sprue or other malabsorption syndrome which may interfere with digestion and absorption of broccoli sprout extract
* Current diagnosis of Gastroesophageal Reflux Disease (GERD) with grade \>3