Symptoms of colon cancer include:
- Change in bowel habits
- Diarrhea, constipation, or feeling that the bowel does not empty completely
- Bright red or very dark blood in the stool
- Narrow stools
- Gas pains, bloating, fullness, and cramps
- Unexplained weight loss
- Chronic fatigue
- Vomiting
Sources:
American Cancer Society. "Colorectal Cancer: Early Detection." American Cancer Society 15 Jun 2013. 22 Jan 2013.
Colon Cancer Alliance. "What Is Colorectal Cancer?" Colon Cancer Alliance 2013. 22 Jan 2013.
National Cancer Institute. "What You Need to Know About Cancer of the Colon and Rectum." National Cancer Institute 26 May 2006. 22 Jan 2013.



