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Colorectal cancer surveillance in inflammatory bowel disease

Authors
Mark A Peppercorn, MD
Robert D Odze, MD, FRCPC
Section Editor
Paul Rutgeerts, MD, PhD, FRCP
Deputy Editor
Shilpa Grover, MD, MPH

INTRODUCTION

Patients with inflammatory bowel disease (IBD) are at increased risk for colorectal cancer [1-9]. The risk is related to the duration and anatomic extent of the disease. The mortality in patients diagnosed with colorectal cancer in the setting of IBD is higher than for sporadic colorectal cancer [7].

Although no large controlled trials have proven that surveillance reduces mortality, cohort studies have demonstrated improved survival in patients with IBD undergoing colonoscopy [10,11]. Surveillance is recommended by the American Gastroenterological Association (AGA) [9,12,13], the American College of Gastroenterology (ACG) [14], the American Society for Gastrointestinal Endoscopy (ASGE) [15], and the British Society of Gastroenterology [16,17].

The epidemiology and pathology of colon cancer in IBD and the evidence supporting a role for cancer surveillance will be reviewed here. Newer techniques for cancer surveillance will also be discussed, although there is insufficient evidence to support their widespread use. The definition, risk factors, clinical manifestations, diagnosis, and management of IBD are discussed separately. (See "Definition, epidemiology, and risk factors in inflammatory bowel disease" and "Clinical manifestations, diagnosis, and prognosis of ulcerative colitis in adults" and "Clinical manifestations, diagnosis and prognosis of Crohn disease in adults" and "Overview of the medical management of mild to moderate Crohn disease in adults" and "Management of severe ulcerative colitis" and "Surgical management of ulcerative colitis".)

EPIDEMIOLOGY

The risk of colorectal cancer (CRC) is increased in ulcerative colitis (UC) and Crohn disease (CD). However, much more is known about the risk in UC. A population-based study from Sweden estimated that the overall risk of colorectal cancer in inflammatory bowel disease (IBD) was 95 cases per 100,000 population [18]. The risk of colorectal cancer in patients with UC appears to have decreased over time but it is unclear if this is due to improved medical therapy and dysplasia surveillance [18,19]. (See "Colorectal cancer: Epidemiology, risk factors, and protective factors".)

It is also unclear if there is a gender difference in the risk for colorectal cancer. In a population-based study of more than 7000 patients with IBD, males had a 60 percent higher risk of CRC than females (cumulative incidence 40 years after diagnosis, 8 versus 3 percent, respectively) [20]. The effect of sex was seen only after ten years of follow-up and limited to patients diagnosed before age 45. This gender difference may be explained by differences in the extent of inflammation, or by factors related to patient behaviors leading to differences in medication or surveillance exposure [21].

                                     

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Literature review current through: Apr 2015. | This topic last updated: Feb 18, 2015.
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