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).
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.
Tests to help your doctor see if colorectal cancer has metastasized or recurred include: An abdominal ultrasound to find the cause of pain or swelling in your abdomen. A colonoscopy to see if cancer has returned to your intestine. Blood tests to find out