Colorectal cancer in inflammatory bowel disease: a shift in risk?

Abstract

Patients with inflammatory bowel disease are at an increased risk for the development of colorectal cancer. However, the magnitude of this risk may not be as high as earlier studies have suggested. This shift in risk may be a result of changes in quality of analyses, aging cohorts, or may indeed represent true declines in the risk of cancer as a result of improvements in medical therapy and surveillance programs. The best surveillance practices for colorectal cancer screening in patients with inflammatory bowel disease remains unclear. The finding of dysplasia on colonoscopy in these patients warrants multi-disciplinary consultation between endoscopist, pathologist, and patient. At present, major organizations offer guidelines for surveillance interval, as well as when surgical consultation is advised. Moreover, newer endoscopic technologies have been developed and their incorporation into dysplasia surveillance programs continues to evolve.

Keywords::

• chromoendoscopy
• Crohn’s disease
• dysplasia
• endoscopy
• inflammatory bowel disease
• surveillance
• ulcerative colitis

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Patients with inflammatory bowel disease (IBD) are at increased risk of colorectal cancer (CRC) due to prolonged states of inflammation that can lead to dysplasia and adenocarcinoma.

• Various factors influence the risk of developing colorectal cancer in patients with IBD including disease extent, location and duration. Ulcerative colitis patients have been shown to have an increased incidence rate of CRC of 18% after 30 years of disease.

• Follow-up studies of population-based studies that showed increase risk of CRC in IBD patients suggest that the initial risk may not be as high as originally thought.

• The histology and endoscopic morphology of polyps must be considered when determining whether to continue active surveillance or to proceed with proctocolectomy. Consultation with an expert pathologist is essential.

• The interval between surveillance endoscopy in patients with IBD should be individualized based on risk factors. Chromoendoscopy is the preferred method, if available, for detection of neoplasia.

• New imaging modalities including chromoendoscopy, narrow band imaging, confocal laser endomicroscopy, autofluorescence imaging and endocytoscopy are being investigated with the goal of detecting dysplasia earlier. It is hoped that further study will allow these methods to become a part of the regular armamentarium of screening tools for endoscopists.