Signs and symptoms of colorectal cancer

Colorectal cancer may cause one or more of the symptoms below. If you have any of the following you should see your doctor:

• A change in bowel habits, such as diarrhea, constipation, or narrowing of the stool, that lasts for more than a few days
• A feeling that you need to have a bowel movement that is not relieved by doing so
• Rectal bleeding, dark stools, or blood in the stool (often, though, the stool will look normal)
• Cramping or abdominal (belly) pain
• Weakness and fatigue
• Unintended weight loss

Most of these symptoms are more often caused by conditions other than colorectal cancer, such as infection, hemorrhoids, or inflammatory bowel disease. Still, if you have any of these problems, it's important to see your doctor right away so the cause can be found and treated, if needed.