Risk of cancer in inflammatory bowel disease: going up, going down, or still the same?

There has been increasing use of immunosuppressive medications as well as better surveillance techniques in inflammatory bowel disease (IBD), which is associated with an increased risk of intestinal and extraintestinal malignancies. We assessed the temporal trends of cancer incidence in IBD patients by reviewing the biomedical literature, performing meta-regression of existing studies, and examining trends in hospitalizations for cancer in IBD patients using a national hospitalization database.

The overall risk of colorectal cancer in ulcerative colitis has decreased in the last 3 decades. The risk of small bowel cancer is significantly elevated among Crohn's disease patients, but there has been no change in incidence rates. The overall risk of non-Hodgkin lymphoma has increased over the last 16 years, and IBD patients on thiopurines and antitumor necrosis factor agents are at increased risk of non-Hodgkin lymphoma. The risk of melanoma in IBD patients is increased, with no significant change over time. The risk of nonmelanoma skin cancer is higher in patients using thiopurines compared with the non-IBD background population, with no significant change over time.

This study points toward a decrease in the incidence of colorectal cancer in ulcerative colitis patients, but an increase in the incidence of lymphoproliferative disorders and nonmelanoma skin cancers with the use of immunosuppressive medications in IBD.