SELECT Biorepository

As the largest cancer prevention trial ever undertaken, the Selenium and Vitamin E Cancer Prevention Trial, or SELECT, has assembled a substantial biorepository of specimens. SWOG Cancer Research Network wants to make these resources available to the wider research community.


SELECT was a phase III, double-blind, placebo-controlled 4-arm study of selenium, vitamin E, selenium and vitamin E together, and placebo designed to assess the effect of these supplements on the incidence of prostate cancer. Funded by the National Cancer Institute and conducted by SWOG, the study opened in August 2001 and quickly exceeded its accrual goal of 35,533 men.

In the fall of 2008, the trial's Data Safety and Monitoring Committee recommended that participants discontinue taking study supplements due to convincing evidence (planned interim futility analysis) that neither vitamin E nor selenium supplements were assicated with the prevention of prostate cancer. A subsequent analysis in 2011 showed a significant 17% increase in prostate cancer incidence in participants who were on the vitamin E only arm. Approximately 17,000 participants from the original trial recently completed an additional four years of centralized follow-up. This follow-up ended on May 31, 2014 and SELECT is now closed.

The Statistical Center is following up on recently reported endpoints. Until that follow-up is complete, the IND will remain open and former SELECT study sites are required to retain research records on SELECT participants. Study sites may monitor the status of record retention requirements by reviewing the List of Protocols With No Required Follow-Up that is available under Reports on the CRA Workbench.

The Statistical Center continues to collaborate on publications and requests for access to the SELECT biorepository.

SELECT Resources

  1. Learn more about SELECT
    1. NCI SELECT site
    2. SELECT in
  2. Summary of trial and results
    1. SELECT and Centralized Follow-Up Study
    2. Data elements collected - summary table
    3. Ancillary studies
    4. Imbedded case-cohort study
  3. Specimens
    1. Blood and tissue acquisition protocols
    2. Biologic samples available
    3. Existing biologic measures
    4. Approved requests
  4. Study documents
    1. Protocol (S0000)
    2. Informed Consent
    3. Major publications regarding primary trial results, study implementation references; instructions on how to get to full Publication list on
    4. Study forms
  5. SELECT data
    1. Baseline characteristics
    2. Endpoints (number of prostate cancers, other cancers, deaths)

Biorepository resources from the Prostate Cancer Prevention Trial (PCPT) are also available.