Topic Overview

Inflammatory bowel disease (IBD)
increases the risk of colon cancer. The amount of increased risk depends on the
type of inflammatory bowel disease (ulcerative colitis or Crohn’s disease of
the colon), how much of the intestine is involved, and how long you have been
ill. The cancer risk usually does not increase until you have
had IBD for 8 years or longer.

Starting 8 years after diagnosis,
most doctors recommend screening for colon cancer every 1 to 3 years. The type
of screening depends on the extent of IBD. For people with ulcerative colitis
that affects only the rectum (proctitis), the increase in cancer risk is
slight. In those cases, some experts feel that screening is not needed. But
sigmoidoscopy sometimes can be used.
Colonoscopy is needed if more of the colon is
involved. The doctor will take small tissue samples (biopsies) in the area
affected by IBD to check for precancerous changes or cancer. If abnormal tissue
is found, surgery may be done, usually to remove the colon (colectomy).

With appropriate screening, some cancers are found early and are

The risk of cancer increases the longer a person
has colitis of the entire colon.

Inflammatory bowel disease also increases the risk of melanoma, a serious type of skin cancer. Your doctor may recommend regular screening by a dermatologist.footnote 1

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  1. Singh S, et al. (2014). Inflammatory bowel disease is associated with an increased risk of melanoma: A systematic review and meta-analysis. Clinical Gastroenterology Hepatology, 12(2): 210-218. DOI: 10.1016/j.cgh.2013.04.033. Accessed March 25, 2015.


ByHealthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD – Internal Medicine
Adam Husney, MD – Family Medicine
Specialist Medical Reviewer Peter J. Kahrilas, MD – Gastroenterology

Current as ofMay 5, 2017