Colorectal cancer in its early stages usually doesn't cause any symptoms. Symptoms occur later, when the cancer may be harder to treat. The most common symptoms include:
- Pain in the belly.
Blood in your stool or very dark stools.
- A change in your bowel habits. (You may have more frequent stools or a feeling that your bowels aren't emptying completely).
- Constant tiredness (fatigue).
- In rare cases, unexplained weight loss.