Symptoms and signs

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 having one.

Rectal bleeding with bright red blood.

Blood in the stool, which might make it look dark brown or black.

Cramping or abdominal (belly) pain.

Weakness and fatigue.

Losing weight without trying.