Vitamin D and Soy Supplements in Treating Patients With Recurrent Prostate Cancer
Condition: Prostate Cancer
MeSH terms: Prostatic Neoplasms
Intervention: Vitamin D; soy
Intervention description: Patients will receive oral supplementation of 2,000 IU per day of vitamin D (cholecalciferol); Patients will receive oral supplementation of soy (160 mg per day soy isoflavones).
Intervention MeSH terms: Vitamin D; Cholecalciferol
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 26.0
Sex: Male
Minimum age: 18 Years
Maximum age: 120 Years
Healthy volunteers: No
Keywords: adenocarcinoma of the prostate; stage I prostate cancer; stage II prostate cancer; stage III prostate cancer

Summary:

      RATIONALE: Vitamin D and soy extract may be effective in lowering prostate-specific antigen
      (PSA) levels in patients with recurrent prostate cancer that has not responded to previous
      treatment.

      PURPOSE: This phase II trial is studying how well giving vitamin D together with soy
      supplements works in treating patients with recurrent prostate cancer.
    

Eligibility criteria:

        Inclusion:

          -  Age > 18 years

          -  Histologically confirmed adenocarcinoma of the prostate

          -  Biochemical relapse following definitive therapy by ASTRO criteria (PSA with 3
             consecutive rising measurements separated by at least one month) and minimum PSA ≥ 1.0
             ng/mL

          -  PSA doubling time of ≥ 6 months, as demonstrated by 3 PSA measurements obtained ≥ 2
             months apart

          -  No hormonal therapy in 6 months prior to enrollment

          -  ECOG performance status 0-2

          -  Life expectancy > 3 months

          -  At least 2 years since prior definitive radiotherapy

          -  No concurrent cholecalciferol, calcium, or soy supplements

          -  Absolute granulocyte count ≥ 1,000/mm³

          -  Platelet count ≥ 100,000/mm³

          -  Hemoglobin ≥ 9.0 g/dL

          -  Creatinine ≤ 2.0 mg/dL

          -  Total bilirubin ≤ 2.0 mg/dL

          -  Calcium > 8.5 mg/dL and < 10.5 mg/dL

          -  Testosterone ≥ 150 ng/dL

        Exclusion:

          -  No clinically evident brain metastases

          -  Concurrent cholecalciferol, calcium, or soy supplements

          -  Concurrent chemotherapy with nonstudy drugs

          -  Serious medical illness that would limit survival to < 3 months, or psychiatric
             condition that would preclude giving informed consent

          -  Other malignancy except nonmelanoma skin cancer, adequately treated stage I or II
             cancer from which the patient is currently in complete remission, or any other cancer
             from which the patient has been disease-free for the past 5 years

          -  Active, uncontrolled bacterial, viral, or fungal infection

          -  Hemorrhagic disorder

          -  Evidence of metastatic disease by bone scan or CT scan

          -  History of hypercalcemia

          -  More History of exposure to other phytotherapeutics, including PC-SPES and Saw
             Palmetto, within the last year.