Cholecalciferol and Genistein Before Surgery in Treating Patients With Early Stage Prostate Cancer

Inclusion Criteria:

Participants must have microscopic confirmation of adenocarcinoma of the prostate within three months of randomization; clinical stage T1 and T2 a, b, or c are allowed
Participants' prostate cancer must be confined to the prostate (in the clinical judgment of the treating physician)
Participants must be candidates for prostatectomy
Participants must have Eastern Cooperative Oncology Group (ECOG) performance status =<1 (Karnofsky >= 70%)
White blood cell (WBC) within normal limits
Platelets >= 100 K/uL
Hemoglobin >= 10 g/dL
Thyroid-stimulating hormone (TSH) =< 4.20 uIU/mL
Free T4 =< 12.5 ng/dL
Bilirubin within upper limit of normal
Aspartate aminotransferase (AST) =< 1.5 x upper limit of normal
Creatinine =< 2.0 mg/dL
Serum calcium: within institutional normal limits
Participants must agree to stop taking nonsteroidal anti-inflammatory drugs (NSAIDS) during the course of the study, however, low dose aspirin (< 100 mg/day) will be allowed; no wash out period is required
Participants must be willing to discontinue consuming soy products and ingesting vitamin supplements while participating in this study
The effects of cholecalciferol and genistein on the developing human fetus at the recommended therapeutic doses are unknown; for this reason, participants must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) for the duration of study participation
Participants must have the ability to understand and sign a consent form indicating the investigational nature of the treatment and its potential risks

Exclusion Criteria:

Participants may not have received any prior therapy for prostate cancer including: chemotherapy, hormonal therapy, brachytherapy, or external radiation
Participants may not be receiving concurrent systemic therapy for other cancers
Participants may not be receiving any other investigational agents
Participants may not be taking the following p450 inducers and inhibitors: carbamazepine, clarithromycin, fluconazole, fosphenytoin, itraconazole, ketoconazole, phenobarbital, phenytoin, rifabutin, rifampin
Participants who took finasteride or dutasteride within 6 months of the pre-randomization biopsy, are currently taking finasteride or dutasteride, or are planning on taking these agents during study participation
Participants with a history of allergic reactions attributed to genistein or placebo, or compounds of similar chemical or biologic composition
Participants with uncontrolled intercurrent illness including, but not limited to ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements
Participants requires thyroid replacement therapy; Note: participants with a history of thyroid disease > 5 years ago, with current normal thyroid function, will be considered eligible
Participant has current, known nephrolithiasis or a history of nephrolithiasis within the past 5 years
Participant has any history of sarcoidosis