Your doctor will review the results of the colonoscopy and then share the results with you.
- Negative result. A colonoscopy is considered negative if the doctor doesn't find any abnormalities in the colon. If you're at average risk of colon cancer — you have no colon cancer risk factors other than age — your doctor may recommend waiting 10 years and then repeating the exam.
Positive result. A colonoscopy is considered positive if the doctor finds any polyps or abnormal tissue in the colon. Most polyps aren't cancerous, but some can be precancerous. Polyps removed during colonoscopy are sent to a laboratory for analysis to determine whether they are cancerous, precancerous or noncancerous.
Depending on the size and number of polyps, you may need to follow a more rigorous screening schedule in the future. If your doctor finds one or two polyps less than 0.4 inches (1 centimeter) in diameter, a repeat colonoscopy in five to 10 years may be adequate, depending on your other risk factors for colon cancer. If you have larger polyps, more polyps or polyps with certain cell characteristics, your doctor may recommend another colonoscopy in three to five years — again, depending on your other risk factors. If one or more cancerous polyps are removed during your colonoscopy, your doctor may recommend a follow-up colonoscopy in as little as three months, six months or a year. If you have a polyp or other abnormal tissue that couldn't be removed during the colonoscopy, your doctor may recommend follow-up surgery.
If your doctor is concerned about the quality of the view through the scope, he or she may recommend a repeat colonoscopy or a shorter time until your next colonoscopy. If your doctor wasn't able to advance the scope through your entire colon, a barium enema or virtual colonoscopy may be recommended to examine the rest of your colon.
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