Columbia subject headings:
Colon (Anatomy)--Cancer--Prevention.
Colon (Anatomy)--Cancer--Risk factors.
Rectum--Cancer--Prevention.
Rectum--Cancer--Risk factors.
Harvard subject headings:
Colon (Anatomy)--Cancer--Prevention
Colon (Anatomy)--Cancer--Risk factors
Rectum--Cancer--Prevention
Rectum--Cancer--Risk factors
Princeton subject headings: