Askling J, van Vollenhoven RF, Granath F et al. Arthritis Rheum 2009;60:3180–9.
Does tumor necrosis factor (TNF) blockade increase the risk of cancer in patients with rheumatoid arthritis (RA)? These nearly complete population data from Sweden found no elevation of cancer risk in TNF-blocker users compared with other RA groups, and no correlation between risk and time of exposure.
For patients with rheumatoid arthritis (RA) considering anti-tumor necrosis factor (anti-TNF) therapy, as well as the physicians who treat them, the possibility of an increased risk of malignancy is a major concern. Askling and colleagues evaluated this possibility in perhaps the most complete and satisfying manner presented to date. Sweden has the benefit of multiple population-based registries, including of RA, anti-TNF therapy (with times of start and discontinuation), and cancers. Analyzing data from these registries, this study group made two important observations. First, the risk of cancers in RA patients receiving anti-TNF therapy (n=6366, median follow-up 3.6 years) was no higher than that in comparator RA populations, with the following relative risks (RR):