Polyps or growths that form in the inner lining of the colon causes colon dysplasia, explains the American Cancer Society. Although a polyp is often benign, the larger and more cancerous it looks, the higher the grade of dysplasia with which it is associated. Severe or high-grade dysplasia describes likely cancerous polyps, while mild dysplasia of the colon includes noncancerous polyps.
Bleeding in the colon causes colon angiodysplasia, states the New York Times. Experts believe that this occurs in the elderly when the blood vessels in the colon begin to age and break down, leading them to swell, bleed and block much of the colon passageway. Although cancer doesn't cause the bleeding, doctors believe that people with blood vessel diseases are more at risk of developing it. Some symptoms of angiodysplasia include fatigue, weakness and anemia.
After determining the condition causing the bleeding, a doctor treats the angiodysplasia by injecting the swollen blood vessels with a medicine designed to decrease inflammation or cauterizing the blood vessel to stop the bleeding, states the New York Times. For those with a severe loss of blood, individuals need transfusions and intravenous fluids and undergo surgery to remove the troublesome part of the colon. However, in mild cases, the bleeding resolves itself over time.