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SELECT: What the Prostate cancer Trial Found

SELECT tested selenium and vitamin E vs placebo in prostate cancer, measuring prostate-cancer incidence. Plain-language summary of a negative or null result on its main measure — and what it doesn't mean.

By Cancer Explained Editorial SystemPublished July 12, 2026

Original commentary from the Cancer Explained editorial team.

Historical context: this page explains an event dated 2009. It was published as an explainer on July 12, 2026 and is not breaking news.

Please note: this page is educational only — it is not medical advice, and it does not speculate about anyone’s health beyond reliable public reporting. For questions about your own health, talk with your healthcare team.

In brief

SELECT was randomized prevention trial in prostate cancer that compared selenium and vitamin E vs placebo and measured prostate-cancer incidence. It reported a negative or null result on its main measure.

Trial at a glance

FieldDetail
TrialSELECT
IdentifierNot recorded here
PhaseSee report
Designrandomized prevention trial
Cancer typeProstate cancer
Comparatorselenium and vitamin E vs placebo
Primary endpointprostate-cancer incidence
Reported resultA negative or null result on its main measure

Who took part

The trial enrolled the population described in its report for prostate cancer.

The main result

The trial's main finding concerned prostate-cancer incidence: SELECT reported a negative or null result on its main measure. Full numbers, follow-up, and statistical detail are held for verification against the peer-reviewed report or trial registry.

What the result means

Results like this help shape research and, sometimes, care — but a trial's finding is one piece of evidence, tied to the specific people and design it used.

What this does not mean

  • A positive trial does not automatically mean a treatment is approved or available; approval and access are separate steps.
  • Improvement on one measure does not always translate into every outcome that matters to patients.
  • Trial participants are selected by specific criteria, so results may not apply to everyone with this cancer.

Questions you might bring to a clinician

  • Does this apply to my specific cancer type and situation?
  • Is this treatment approved and available, or still investigational?
  • What are the main side effects, and how would they be managed?

Sources

This article was written from the sources below, which were checked on the source-check date shown above.

How this article was prepared

Prepared by Cancer Explained's AI-assisted editorial system and checked against the sources listed below. This article has not been reviewed by a healthcare professional unless a named reviewer is specifically shown.

Cancer Explained is published by the National Cancer Information Foundation as a nonprofit-oriented public-interest education project. It is not a diagnostic service, does not recommend treatments, and is not for emergencies.

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