Using data from over 1.5 million patients from 47 studies, the researchers analysed the association between four autoimmune diseases, most of which are acquired in childhood or younger adulthood, and cancers of the gastrointestinal tract, liver and pancreas. "We obtained very robust results with minimal bias," says Dr Dennis Freuer, research associate at the Department of Epidemiology and head of the study.
The study shows that coeliac disease, systemic lupus erythematosus and type 1 diabetes increase the risk of several types of cancer of the digestive tract. These include stomach and bowel cancer. In particular, the risk of small bowel cancer increases by a factor of 4.2 if coeliac disease is present. Multiple sclerosis, on the other hand, is associated with a lower risk of certain types of cancer, such as pancreatic, oesophageal and rectal cancer.
"Our results underline the need for targeted monitoring of patients with autoimmune diseases and the development of personalised cancer prevention programmes," explains Julia Reizner, first author of the paper. Prof Christa Meisinger, physician and epidemiologist on the research team, emphasizes the role of chronic inflammation as a possible driver for the development of cancer and calls for further research into the underlying mechanisms, including the effects of immunotherapies. "The study thus provides important impetus for clinical practice and the development of preventive strategies."
