Vitamin D Supplementation in Veterans With Early-Stage Prostate Cancer
Condition: Prostate Cancer
MeSH terms: Prostatic Neoplasms
Study type: Interventional
Phase: Phase 2

Summary: 
      Vitamin D promotes the differentiation of prostate cancer cells, maintains the differentiated
      phenotype of prostate epithelial cells, and can induce prostate cancer cell death, raising
      the possibility that vitamin D deficiency over time promotes the progression of subclinical
      prostate cancer to clinical disease. The investigators propose to conduct a clinical study
      aimed at measuring the efficacy of vitamin D3 (4000IU/day) supplementation in Veterans
      diagnosed with low-risk, early-stage prostate cancer, who elect to have their disease
      monitored through active surveillance. The successful completion of this proposed clinical
      study will allow us to determine whether correcting vitamin D deficiency in Veterans
      diagnosed with early-stage prostate cancer will prevent progression of their disease and
      improve their prognosis.
    

Detailed description: 
      Vitamin D promotes the differentiation of prostate cancer (PCa) cells, maintains the
      differentiated phenotype of prostate epithelial cells, and can induce prostate cancer cell
      death, raising the possibility that vitamin D deficiency over time promotes the progression
      of subclinical PCa to clinical disease. These considerations support the use of vitamin D3 as
      a chemopreventive agent.

      We hypothesize that a daily dose of vitamin D3 (4,000 IU) taken for one year by Veterans
      diagnosed with low-risk, early-stage PCa, who are eligible for active surveillance will: a)
      result in a measurable decrease of serum PSA levels in a significant number of enrolled
      subjects, and b) be associated with a stabilization or improvement of their PCa pathology, as
      assessed through histological examination of prostate tissue biopsy specimens (Gleason score
      and percent of positive biopsies) obtained at the end of the study, as part of their standard
      medical care for active surveillance.

      This VA Merit application proposes to conduct a randomized, placebo-controlled clinical study
      aimed at measuring the efficacy of vitamin D3 (4000IU/day) supplementation in Veterans
      diagnosed with early-stage prostate cancer, who elect to have their disease monitored through
      active surveillance (before considering definitive therapy). The main objectives of this
      proposed clinical study are as follows:

        1. To determine whether a daily supplement of 4,000 IU of vitamin D3 taken for twelve
           months will result in a measurable and significant decrease of serum PSA levels in
           Veterans diagnosed with low-risk, early stage PCa (Gleason score 6, PSA 10, clinical
           stage T1C or T2a), who elect to have their disease monitored through active surveillance
           for at least one year.

        2. To determine in enrolled Veterans the pathology status of their PCa by analyzing
           prostate tissue biopsy specimens at the end of the study (Gleason score and percentage
           of positive biopsies), and by comparing them with those obtained before enrollment in
           this study, as part of their standard medical care.

      The implementation of these proposed studies will allow us to assess whether vitamin D3
      supplementation can be utilized as a chemopreventive regimen in Veterans diagnosed with
      low-risk, early stage PCa, and provide a useful addition to active surveillance.
    

Intervention name(s): vitamin D3; Placebo daily for one year
Intervention type(s): Drug; Drug
Intervention description(s): 4,000 IU daily for one year; Placebo
Intervention MeSH terms: Vitamin D; Cholecalciferol
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: prostate cancer; vitamin D