Published online May 28, 2016. doi: 10.3748/wjg.v22.i20.4794
Peer-review started: February 11, 2016
First decision: March 21, 2016
Revised: March 25, 2016
Accepted: April 7, 2016
Article in press: April 7, 2016
Published online: May 28, 2016
In patients with inflammatory bowel disease (IBD), chronic inflammation is a major risk factor for the development of gastrointestinal malignancies. The pathogenesis of colitis-associated cancer is distinct from sporadic colorectal carcinoma and the critical molecular mechanisms underlying this process have yet to be elucidated. Patients with IBD have also been shown to be at increased risk of developing extra-intestinal malignancies. Medical therapies that diminish the mucosal inflammatory response represent the foundation of treatment in IBD, and recent evidence supports their introduction earlier in the disease course. However, therapies that alter the immune system, often used for long durations, may also promote carcinogenesis. As the population of patients with IBD grows older, with longer duration of chronic inflammation and longer exposure to immunosuppression, there is an increasing risk of cancer development. Many of these patients will require cancer treatment, including chemotherapy, radiation, hormonal therapy, and surgery. Many patients will require further treatment for their IBD. This review seeks to explore the characteristics and risks of cancer in patients with IBD, and to evaluate the limited data on patients with IBD and cancer, including management of IBD after a diagnosis of cancer, the effects of cancer treatment on IBD, and the effect of IBD and medications for IBD on cancer outcomes.
Core tip: Patients with inflammatory bowel disease (IBD) and cancer represent a challenging population. Gastroenterologists and oncologists caring for patients with IBD and cancer are increasingly confronted with questions regarding the management of IBD after a diagnosis of cancer, and conversely, the management of cancer in patients with IBD. This review seeks to explore the characteristics, risks, and pathogenesis of cancer in patients with IBD, and to evaluate the data on patients with IBD and cancer, including the interaction between IBD and cancer treatment.