Colorectal Cancer Risk in IBD

Colorectal cancer risk and IBD

Patients with IBD appear to be at notably increased risk of colorectal cancer compared to the general population [1-3], with one recent study demonstrating a 7% colorectal cancer risk after 30 years of disease [4]. Patients with at least 8 years disease duration and colonic involvement are at increased risk of colorectal cancer (excluding patients with only ulcerative proctitis, or with Crohn’s disease and less than 1/3 of the colon involved). Patients at risk of colorectal cancer should be enrolled in a dysplasia surveillance plan as this appears to reduce the risk of colorectal cancer[5]. Surveillance typically includes colonoscopy every 1-3 years, depending on individual patient risk [6, 7].

Risk factors and surveillance intervals

In patients at high risk, consider ~1 year surveillance intervals. High risk features include: primary sclerosing cholangitis (PSC), prior history of dysplasia or colonic strictures, or strong family hx of colorectal cancer (e.g., 1^st degree relative with CRC < age 50). Patients with low to moderate risk may be surveyed every 2-3 years. Moderate risk features include: extensive colitis with moderate inflammatory burden, family hx of CRC in first degree relative > age 50 and possibly extensive inflammatory polyps or pseudopolyps [6, 8]

Surveillance Protocols

Most colonic dysplasia should be visible, hence a thorough high-quality exam is essential. High definition colonoscopes are preferred. Use of dye spray (chromoendoscopy) may have additional benefits for detecting dysplasia[9-13]. Random biopsies are typically performed in 4 quadrant fashion every 10cm. However, yield from random biopsies is low and this could be skipped if chromoendoscopy is utilized[8].

Management of Endoscopic lesions

Any visible polyps or lesions should be endoscopically resected if feasible and the specimen should be sent in a separately labeled jar. If a lesion has indistinct borders or is not amenable to resection, biopsy sample should be taken and sent in a separate jar[6, 8].

Management of Dysplasia

A diagnosis of dysplasia should ideally be confirmed by two experienced pathologists. Dysplasia should be managed closely and aggressively to prevent progression to cancer. For any confirmed case of high-grade dysplasia or multi-focal low-grade dysplasia, proctocolectomy should be recommended. For isolated unifocal dysplasia, options include proctocolectomy or close colonoscopic surveillance.

References

1. Jess, T., C. Rungoe, and L. Peyrin-Biroulet, Risk of colorectal cancer in patients with ulcerative colitis: a meta-analysis of population-based cohort studies. Clin Gastroenterol Hepatol, 2012. 10(6): p. 639-45.

2. Lutgens, M.W., et al., High frequency of early colorectal cancer in inflammatory bowel disease. Gut, 2008. 57(9): p. 1246-51.

3. Eaden, J.A., K.R. Abrams, and J.F. Mayberry, The risk of colorectal cancer in ulcerative colitis: a meta-analysis. Gut, 2001. 48(4): p. 526-35.

4. Selinger, C.P., et al., Long-term follow-up reveals low incidence of colorectal cancer, but frequent need for resection, among Australian patients with inflammatory bowel disease. Clin Gastroenterol Hepatol, 2014. 12(4): p. 644-50.

5. Choi, C.H., et al., Forty-Year Analysis of Colonoscopic Surveillance Program for Neoplasia in Ulcerative Colitis: An Updated Overview. Am J Gastroenterol, 2015. 110(7): p. 1022-34.

6. Rubin, D.T., et al., ACG Clinical Guideline: Ulcerative Colitis in Adults. American Journal of Gastroenterology, 2019. 114(3): p. 384-413.

7. Lichtenstein, G.R., et al., ACG Clinical Guideline: Management of Crohn's Disease in Adults. American Journal of Gastroenterology, 2018. 113(4): p. 481-517.

8. Magro, F., et al., Third European Evidence-based Consensus on Diagnosis and Management of Ulcerative Colitis. Part 1: Definitions, Diagnosis, Extra-intestinal Manifestations, Pregnancy, Cancer Surveillance, Surgery, and Ileo-anal Pouch Disorders. Journal of Crohn's and Colitis, 2017. 11(6): p. 649-670.

9. Feuerstein, J.D., et al., Meta-analysis of dye-based chromoendoscopy compared with standard- and high-definition white-light endoscopy in patients with inflammatory bowel disease at increased risk of colon cancer. Gastrointest Endosc, 2019. 90(2): p. 186-195.e1.

10. Laine, L., et al., SCENIC International Consensus Statement on Surveillance and Management of Dysplasia in Inflammatory Bowel Disease. Gastroenterology, 2015. 148(3): p. 639-651.e28.

11. Carballal, S., et al., Real-life chromoendoscopy for neoplasia detection and characterisation in long-standing IBD. Gut, 2018. 67(1): p. 70-78.

12. Iacucci, M., et al., A Randomized Trial Comparing High Definition Colonoscopy Alone With High Definition Dye Spraying and Electronic Virtual Chromoendoscopy for Detection of Colonic Neoplastic Lesions During IBD Surveillance Colonoscopy. Am J Gastroenterol, 2018. 113(2): p. 225-234.

13. Yang, D.-H., et al., High-Definition Chromoendoscopy Versus High-Definition White Light Colonoscopy for Neoplasia Surveillance in Ulcerative Colitis: A Randomized Controlled Trial. American Journal of Gastroenterology, 2019. 114(10): p. 1642-1648.