Colorectal Cancer Health Center
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Understanding Colorectal Cancer - Symptoms
What Are the Symptoms?
In its early stage, colorectal cancer usually produces no symptoms. The most likely warning signs include:
- Changes in bowel movements, including persistent constipation or diarrhea, a feeling of not being able to empty the bowel completely, or rectal bleeding
- Dark patches of blood in or on stool; or long, thin, "pencil stools."
- Abdominal discomfort or bloating
- Unexplained fatigue, or loss of appetite or weight
Call Your Doctor If:
- You notice a change in your bowel movements, experience bleeding from the rectum, or notice blood in or on your stool. Don't assume you have hemorrhoids; your doctor will most likely perform a rectal examination and possibly a sigmoidoscopy or schedule a colonoscopy -- an examination that involves a long flexible tube inserted in your rectum.
- You experience persistent abdominal pain, unusual weight loss, or fatigue. These symptoms may be due to other causes, but they could also be linked to cancer.
- You are diagnosed with anemia. In determining its cause, your doctor should check for bleeding from the digestive tract because of colorectal cancer.
WebMD Medical Reference provided in collaboration with the Cleveland Clinic![]()
Reviewed by
Paul O'Neill, MD on May 01, 2007
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