This section has been reviewed and approved by the Cancer.Net Editorial Board, 12/10
By being alert to the symptoms of colorectal cancer, it may be possible to detect the disease early, when it is most likely to be treated successfully. However, many people with colorectal cancer do not have any symptoms until the disease is advanced, so people need to bescreened regularly. People with colorectal cancer may experience the following symptoms or signs. It is also possible that these symptoms may be caused by a medical condition that is not cancer.
This is particularly true for the general symptoms of abdominal discomfort, bloating, and irregular bowel movements. Talk with your doctor if these symptoms last for several weeks or become more severe. And talk with your doctor if you are concerned about any symptom or sign on this list and ask to schedule a colonoscopy to find the underlying reason(s).
- A change in bowel habits
- Diarrhea, constipation, or feeling that the bowel does not empty completely
- Bright red or very dark blood in the stool
- Stools that look narrower or thinner than normal
- Discomfort in the abdomen, including frequent gas pains, bloating, fullness, and cramps
- Weight loss with no known explanation
- Constant tiredness or fatigue
- Unexplained iron-deficiency anemia (low number of red blood cells)
Since colon cancer can occur in people younger than the recommended screening age and in older people between screenings, anyone at any age who experiences these symptoms should be evaluated by a doctor to determine if he/she should have a colonoscopy.