A recent article has shown that the absolute lymphoma risk from medications in children and young adults with IBD is quite low (Inflamm Bowel Dis 2012; 18: 838-43).
In this single center study from 1979-2008, 1374 pediatric IBD patients had charts reviewed to determine whether lymphoma developed. In total, two male patients who had received thiopurines developed lymphoma (one Hodgkin, one anaplastic large cell) in 6624 patient-years of follow-up. Both patients are alive after chemotherapy. Mean follow-up was 4.8 years per patient. The absolute lymphoma incidence rate was 3 per 10,000 patient-years; after thiopurine exposure, the rate was 4.5 per 10,000 patient-years compared to an expected 0.58 per 10,000 patient-years.
In this study, 22% of the patients had received TNF inhibitors. None developed lymphoma. The risk of biologics could not be fully assessed due to a limited study period: 713 person-years taking the medication.
The risk of thiopurine-associated lymphoma was similar to previous studies but did not reach statistical significance. As related in other studies, the risk of biologic agents, like Remicade, Humira, and Cimzia, is heavily influenced by whether patients had also received immunomodulators.
One useful way to try to convey this risk has been with diagrams. One useful diagram is a palette of one thousand people or of 10,000 people showing the absolute risk and one showing the risk for other complications like infection. You can make your own by going to the following link:
Additional references/blog entries:
Only one chance to make first impression
Biologics | Living Longer | Arthritis Today Magazine -From Arthritis magazine: biologics improve survival in Rheumatoid arthritis
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