Risk of Lymphoma Increased in People Taking Thiopurines for IBD

A meta-analysis of 18 cohort studies shows that people with inflammatory bowel disease (IBD) who take thiopurines are at a nearly six-fold increased risk of developing lymphoma compared to the general population.

Specifically, Dr. David Kotlyar of the National Cancer Institute and colleagues found that these patients had a 5.7-fold greater incidence of lymphoma over the general population.

This increased risk only applied to people who took thiopurines (azathioprine or 6-mercaptopurine) for at least one year. Risk appeared to drop back down to that of the general population after patients stop taking thiopurines. This, according to researchers, suggests that the mechanism of carcinogensis is not DNA damage, but rather suppression of the immune system by this class of drugs.

"It is important to emphasize that although the relative risks of lymphoma in active users are moderate, there remains a very low absolute risk of lymphoma for any given patient," wrote researchers. "For patients of all ages and genders, the risk of lymphoma needs to be weighed against the potential benefits of therapy. Further work is needed to understand how this trade-off of potential benefit and harm varies by age, particularly in the era of combination immunosuppression therapy."

The team reported their findings in the journal Clinical Gastroenterology and Hepatology.

Source: Oncologypractice.com