Crohn's disease and colorectal cancer.

Background: The patients with Crohn’s disease (CD) have a greater risk of gastrointestinal and hemopoietic cancers compared with background population. Identify groups of people affected by CD with exposition to factors that play a role in the development of cancer could be useful to plan correct diagnostic and therapeutic methods. Methods: A reaserch on “pubmed” with “Risk factors for cancer in patients with Crohn’s disease”, “Cancer and Crohn’s disease”, Crohn’s disease and cancer risk” as key-words was conducted. We identified 35 studies and analized also references reported inside each single work. Results: Patients with CD have a higher risk of colorectal cancer (CRC). The risk of colon cancer alone was found to be increased, with no significant increase in the risk of rectal cancer. Factors that play a role in the development of CRC are: diagnosis of CD before 25 years old, duration of disease, severity of inflammation, habit to cigarette’s smoke, a familial history of CRC and immunosuppressive therapies. The risk of small bowel cancer was found to be increased, even if overall risk remains low. Although the role of immunosuppressive therapies remain to clarify yet, patients with CD have a higher risk of development lymphoma compared with background population. Conclusions: Patients with CD are at high risk of large bowel, small bowel, extraintestinal and hemopoietic cancers. Selected patients with extensive colonic disease, which has been present from a young age, are at high risk of cancer and should be candidates for colonscopic surveillance.