There are many types of problems that can occur in the colon. The medical history, physical exam, laboratory tests and x-rays can provide information useful in making a diagnosis. Directly viewing the inside of the colon by colonoscopy is usually the best exam. Colonoscopy is used for:

• Colon cancer — a serious but highly curable malignancy
• Polyps — fleshy tumors which usually are the forerunners of colon cancer
• Colitis (ulcerative or Crohn's) — chronic, recurrent inflammation of the colon
• Diverticulosis and diverticulitis — pockets along the intestinal wall that develop over time and can become infected
• Bleeding lesions — bleeding may occur from different points in the colon
• Abdominal symptoms, such as pain or discomfort, particularly if associated with weight loss or anemia
• Abnormal barium x–ray exam
• Chronic diarrhea, constipation, or a change in bowel habits
• Anemia

Colon surgery is used to treat cancer and polyps in some cases, as well as to treat hernias. hemorrhoids and diverticulitis.