Certain patients with inflammatory bowel disease, which includes ulcerative colitis and Crohn's disease of the colon, have an increased risk of developing colorectal cancer compared to individuals without IBD, which necessitates an individualized and sensible approach to CRC surveillance in patients, according to the American Gastroenterological Association.
The medical position was published in the AGA's official journal, Gastroenterology.
While IBD is relatively rare in the general population, it remains one of the three high-risk conditions predisposing patients to CRC, along with Lynch syndrome and familial adenomatous polyposis, according to the release.
Additional findings of the AGA's medical position statement on diagnosis and management of CRC in IBD patients include the following:
- Disease duration, more extensive disease, severity of inflammation, primary sclerosing cholangitis and a positive family history of sporadic CRC are all associated with an increased risk of developing CRC.
- Dysplasia detected on biopsy is currently considered the best marker for CRC risk in IBD.
- Patients with IBD and a non-adenoma-like dysplasia-associated lesion or mass that does not lend itself to being completely removed by colonoscopy should be treated with colectomy. In contrast, patients with an adenoma-like dysplasia-associated lesion or mass removed endoscopically and without evidence of flat dysplasia elsewhere in the colon, can be managed safely by polypectomy and continued surveillance.
- There is a high certainty that colectomy for flat high-grade dysplasia treats undiagnosed synchronous cancer (which may be present in 42 percent to 67 percent of cases).
- The controversy revolving around the management of low-grade dysplasia was reviewed.
- There is moderate certainty that surveillance colonoscopy results in at least moderate reduction of CRC risk in patients with IBD. Patients with extensive ulcerative colitis or Crohn's disease involving much of the colon are the most likely to benefit.
- The authors endorsed the use of chromoendoscopy in high risk patients to identify dysplasia and cancer.
- While there is some evidence that certain medicines used to treat IBD might help to prevent CRC and dysplasia, this requires further research.
- At present, there are no genetic, molecular or biochemical markers that can be measured in the tissue, blood or stool to reliably predict which patients with IBD are at greater risk for dysplasia or cancer, but this is an area of active investigation.
More information regarding the authors' review process and development of screening guidelines along with additional information on IBD and CRC are available at the AGA's Web site.
Read the AGA's release on colon cancer surveillance in IBD patients.