Age

50–any

Sex

ALL

Healthy volunteers

Accepted

The following will be specifically looked for, and result in patients not being eligible for study enrollment:
* Use of non-steroidal anti-inflammatory drugs or glucocorticosteroids within 60 days of study entry.
* History of chronic IBD or prior pelvic radiation (inflammation distorts crypt pattern).
* Intake of any selenium supplements within 60 days of study entry, including vitamins.
* Patients with increased bleeding risk from biopsy protocol (i.e. renal failure, decompensated cirrhosis, blood dyscrasia).

Colon Cancer Prevention Using Selenium