S0000D: Effect of Vitamin E and/or Selenium on Colorectal Polyps in Men Enrolled on SELECT Trial SWOG-S0000

Phase 3

Completed

Interventions: Drug: Vitamin E
Drug: Selenium
Drug: Vitamin E placebo
Drug: selenium placebo

Brief Summary: RATIONALE: Studying tissue samples in the laboratory from participants receiving treatment on the Selenium and Vitamin E Cancer Prevention Trial (SELECT) SWOG-S0000 may help doctors predict a participant's response to treatment and help plan the best treatment.

PURPOSE: This phase III trial is studying the effect of vitamin E and/or selenium on colorectal polyps in men enrolled on SELECT Trial SWOG-S0000.

Detailed Description: OBJECTIVES:

Primary

* To assess the effect of selenium on colorectal adenoma (CRA) occurrence.

* To assess the effect of selenium on number, location, size, histologic type, and degree of dysplasia of CRA.

* To assess the effect of selenium on colorectal cancer (CRC) incidence.

Secondary

* To assess the effect of vitamin E on CRA occurrence.

* To assess the effect of vitamin E on CRC incidence.

Tertiary

* To explore the effect modification of selenium and vitamin E by aspirin on CRA occurrence.

* To explore the effect modification of selenium and vitamin E by body mass index.

OUTLINE: This is a multicenter study.

Endoscopically obtained tissue samples are reviewed by study pathologists to confirm the presence (or absence) of a colorectal adenoma (CRA). If a CRA is present, the number, location, size, histology, and degree of dysplasia are documented. The CRA is also reviewed to exclude a diagnosis of colorectal cancer.

Additional data, including aspirin use, height and weight, date of birth, and other demographic and baseline characteristics, is also obtained. Participants' medical records are reviewed periodically.

Participants are followed annually.

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
Selenium + vitamin E placebo	Vitamin E placebo	Selenium and vitamin E placebo daily for 7 - 12 years
Vitamin E + selenium	Vitamin E	Vitamin E and selenium daily for 7 - 12 years
Vitamin E placebo + selenium placebo	Vitamin E placebo	Vitamin E placebo and selenium placebo daily for 7 - 12 years
Vitamin E + selenium placebo	selenium placebo	Vitamin E and selenium placebo daily for 7 - 12 years
Selenium + vitamin E placebo	Selenium	Selenium and vitamin E placebo daily for 7 - 12 years
Vitamin E + selenium placebo	Vitamin E	Vitamin E and selenium placebo daily for 7 - 12 years
Vitamin E placebo + selenium placebo	selenium placebo	Vitamin E placebo and selenium placebo daily for 7 - 12 years
Vitamin E + selenium	Selenium	Vitamin E and selenium daily for 7 - 12 years

Primary Outcome Measures

Name	Time	Method
Effect of Selenium on Advanced Neoplasia, Analyzed by Active Selenium vs. Selenium Placebo	From 1 year post randomization through study completion	Adenomas with diameter \>=1cm or any adenoma with villous features or high-grade dysplasia
Effect of Selenium and/or Vitamin E on Colorectal Cancer (CRC) Incidence	From 1 year post randomization through study completion
Effect of Selenium on Colorectal Adenoma (CRA) Occurrence, Analyzed by Active Selenium vs. Selenium Placebo	From 1 year post randomization through study completion
Effect of Selenium on Occurrences of Multiple (>2) Adenomas	From 1 year post randomization through study completion