ABSTRACT
Since the initial description of Crohn 's disease in 1932, much has been learned about the natural history of this complex disease (1). In 1948, Warren and Sommers reported the first case of colorectal carcinoma associated with Crohn's disease (2). Since that time, the risk of developing cancer in Crohn 's disease has become better appreciated. In particular, recent studies suggest that the risk of developing colorectal cancer in patients with Crohn 's disease may be significantly elevated (3-8). In addition, these studies indicate that risk factors for developing colorectal cancer in Crohn 's disease may be similar to that seen in ulcerative colitis (9). For example, there appears to be an important relationship between the risk of developing colorectal cancer and the duration of disease and extent of colonic involvement. Other features including the young age at cancer development, presence of dysplasia, and various other pathological features have also been found to be nearly identical to those found in patients with ulcerative colitis. Patients with Crohn's disease also appear to be at risk for development of small bowel cancer, particularly in patients with small bowel disease of long duration (10). There may also be an association between Crohn's disease and the risk of development of cholangiocarcinoma (11). The risk of other malignancies developing in Crohn's disease does not appear to be significantly elevated (7). With the better understanding of the risk and natural history of malignancies in Crohn's disease, more effective cancer prevention strategies and, thereby, an improved overall prognosis for affected patients may become possible.
