Colon Cancer Symptoms

• A change in bowel habits — constipation or diarrhea that lasts more than a couple of weeks. 
• A feeling that the bowel does not empty completely. 
• Bright red or very dark blood in the stool, black stools that may indicate hidden blood. 
• Stools that look narrower or thinner than normal. 
• Abdominal discomfort such as frequent gas pains, bloating, fullness, or cramps. 
• Weight loss with no known explanation. 
• Constant tiredness or fatigue. 
• Unexplained anemia (low number of red blood cells).