Blood in the stool or rectal bleeding
A change in bowel habits lasting more than a few weeks
Diarrhea, constipation, or narrowing of the stool
Persistent abdominal pain, cramps, or bloating
A feeling that the bowel does not empty completely
Unexplained weight loss
Unexplained fatigue or weakness
Iron-deficiency anemia
Nausea or vomiting
A lump in the abdomen
Symptoms that keep getting worse over time
A personal history of colon polyps or colon cancer
A family history of colon cancer or inherited colon cancer syndromes
Age 45 or older with no recent screening
Positive stool test or abnormal colonoscopy result
Seek medical evaluation promptly if any of these symptoms occur