Colorectal cancer in its early stages usually doesn't cause any symptoms. Symptoms occur later, when the cancer may be more difficult to treat. The most common symptoms include: Pain in the belly. Blood in your stool or very dark stools. A change in your
Cancer is the growth of abnormal cells in the body; these extra cells grow together and form masses, called tumors. In colorectal cancer, these growths usually start as polyps in the large intestine (colon or rectum).
Radiation therapy uses X-rays to destroy colorectal cancer cells and shrink tumors. It is often used to treat rectal cancer, usually combined with surgery. It is used less often to treat colon cancer. It may also be combined with chemotherapy.
Call your doctor if you have any symptoms of colorectal cancer, such as a change in bowel habits, bleeding from your rectum, including bright red or dark blood in your stools, or constant or frequent diarrhea or constipation.