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Colorectal cancer: Watch for these potential signs

Getting screened is the best way to find colorectal cancer early—before it causes symptoms, which is when it’s often more treatable. But it’s also important to see your doctor if you notice any of these potential colorectal cancer warning signs.

Signs and symptoms of colorectal cancer

A change in bowel habits, such as ongoing diarrhea, constipation or narrowing of stools.
Blood in the stool or very dark or black stools.
A feeling of incomplete bowel emptying.
Abdominal pain or cramps.
Feeling very weak or tired.
Losing weight without trying.

Ask your doctor if it’s time to be screened for colorectal cancer. You can choose from different tests, including some you can take at home. Learn about your options.

Reviewed 4/4/2025

Source

American Cancer Society. "Colorectal Cancer Signs and Symptoms."
https://www.cancer.org/cancer/colon-rectal-cancer/detection-diagnosis-staging/signs-and-symptoms.html.