Inflammatory Bowel Disease and Colorectal Cancer

Abstract

One of the long-term risks of inflammatory bowel disease is the development of cancer. Patients with either non-specific or specific forms of disease are at increased risk for various types of intestinal (Greenstein et al. 1980, 1981; Gyde et al. 1980) or extraintestinal (Greenstein et al. 1985) cancers. The non-specific forms of chronic inflammatory bowel disease comprise ulcerative colitis and Crohn’s disease, common in the British Isles, Scandinavia, Western Europe, and North America; a specific form with possible increased cancer risk is schistosomiasis, endemic in much of the Far East, China, the Philippines, Egypt, and the rest of Africa. The increased risk of colorectal cancer is unequivocal in ulcerative colitis, highly probable, albeit somewhat controversial, in Crohn’s colitis, and still debatable in schistosomiasis. In each of these three forms of inflammatory bowel disease, there are cancers for which the risk is increased: reticuloendothelial tumors in ulcerative colitis and Crohn’s disease (Greenstein et al. 1985; Hanauer et al. 1982), perineal cancers (Greenstein et al. 1985; Slater et al. 1984) and malignant melanoma (Greenstein et al. 1985) in Crohn’s disease, and genitourinary (Alexis and Domingo 1986; Ghoneim et al. 1985) and hepatic (Kojiro et al. 1986) cancers in schistosomiasis, associated with Schistosoma haematobium and Schistosoma japonicum, respectively.