Risk for colorectal cancer in ulcerative colitis: Changes, causes and management strategies

Abstract

Since the first report of an inflammatory bowel disease (IBD) case associated with colorectal cancer (CRC) by Crohn and Rosenberg [1] , significant efforts have been made to elucidate this presumed association. Nowadays, the association between IBD and the increased risk for CRC is widely accepted. Although CRC, complicating ulcerative colitis and Crohn's disease, accounts only for 1%-2% of all cases of CRC in the general population, it is considered a serious complication of the disease and accounts for approximately 10%-15% of all deaths in IBD patients [2] . The age at diagnosis of CRC associated with IBD is 15-20 years earlier compared to sporadic cancers. In the meta-analysis by Eaden et al [3] , the average age at diagnosis was 43.2 years. Similarly, in a recent publication from Eastern Europe [4] , it was found to be 50.9 years, 10-15 years younger compared to sporadic CRC cases from the same area (62.2 years) [5] . According to US [6] and Canadian [7] publications, almost two-thirds of the affected patients were males, yet results are conflicting [4,8] . In addition, the frequency of multiple CRCs is higher than in patients with sporadic CRC [9] .The increased risk of CRC in UC is almost a universal finding [3,[10][11][12][13] , yet the extent of this risk varies considerably with differences in study design and geographic area. The initial reports were published by tertiary gastroenterology centers, thus the high risk detected might have been a consequence of referral bias and overinterpretation due to the high percentage of extensive and chronically active cases in these cohorts. Results of population-based studies are more reliable; however, several geographical and ethnic differences have been noted.The report of the meta-analysis by Eaden et al [3] in 2001 was one of several milestones in this subject. The incidence of UC-associated CRC was estimated based on 116 articles involving 54 478 patients in whom 1698 CRC cases were detected. This was a mixture of referral center-based, hospital-based, and population-based studies of variable methodological qualities and levels of detail. The reported incidence was higher in the US AbstractThe risk of colorectal cancer for any patient with ulcerative colitis is known to be elevated, and is estimated to be 2% after 10 years, 8% after 20 years and 18% after 30 years of disease. Risk factors for cancer include extent and duration of ulcerative colitis, primary sclerosing cholangitis, a family history of sporadic colorectal cancer, severity of histologic bowel inflammation, and in some studies, young age at onset of colitis. In this review, the authors discuss recent epidemiological trends and causes for the observed changes. Population-based studies published within the past 5 years suggest that this risk has decreased over time, despite the low frequency of colectomies. The crude annual incidence rate of colorectal cancer in ulcerative colitis ranges from approximately 0.06% to 0.16% with a relative risk of 1.0-2.75. The exact mechanism for this chang...

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Hepatocyte growth factor ameliorates mucosal injuries leading to inhibition of colon cancer development in mice

“…Therefore, treatment that enhances the remodeling and repair of injured mucosa may be essential for the treatment of IBD; this approach may ultimately prove to be more successful than either anti-inflammatory or anti-immune therapy. However, the evident mitogenic activity of HGF has the potential to increase the risk of cancer development; and in patients with IBD, particularly those with ulcerative colitis, the risk of colorectal cancer continuously increases with the duration of the disease (14,15). In fact, recent investigations have reported that the cumulative risk for colorectal cancer ranges between 10-18% in patients with a disease history of 30 or more years (16,17), and that colitis-associated colorectal cancer is responsible for 10-15% of all deaths in UC patients (18 HGF to treat IBD patients are developed, it must first be ascertained, whether repeated doses of recombinant HGF increase the risk of accelerating the development of colorectal cancer, particularly colitis-associated colorectal cancer, and second, whether HGF-induced enhanced repair of injured mucosa leads to prevention of colitis-associated colorectal cancer.…”