Rheumatoid arthritis (RA) patients taking biologic therapy (tumor necrosis factor antagonists) have a higher risk of certain cancers, according to research. The risk of cancer in RA patients on biologics has long been a controversial topic, so researchers decided to compare relative risk of cancer in RA patients taking biologics and patients taking non-biologic disease-modifying antirheumatic drugs (nbDMARDs).
For the study, researchers conducted a nationwide cohort study between 1997 and 2011 using the Taiwan National Health Insurance Research Database. Relative risk of cancer was compared between patients taking either biologics or nbDMARDs.
The researchers compared 4,426 new users of the biologic therapy and 17,704 nbDMARD users. Incidence risk of cancer was 5.35 and 7.41 per 1,000 person-years, respectively.
The study concluded that overall there was a lower risk of cancer in patients on biologics, except for hematologic cancer, compared to those taking nbDMARDs.
Rheumatoid arthritis and the link to cancer types
Overall, cancer risk in rheumatoid arthritis patients is relative to the general public, but RA patients may have a higher risk of certain types of cancer, compared to the general public. RA patients have a higher risk of developing lymphoma and lung tumors, for example, but experience lower rates of colon and breast cancers.
RA patients taking certain biologics – TNF inhibitors – may also be at a greater risk for certain cancers, as those medications inhibit inflammation, but raise the risk of malignancy. This has caused the FDA to put warnings on these types of medications.
One study that looked at 5,000 RA patients found that there was a significantly higher risk for malignancy in patients taking adalimumab or infliximab, compared to those taking a placebo. Even still, many other meta-analysis studies did not find similar results, and so whether taking certain medications for rheumatoid arthritis treatment raises the risk of cancer still remains a debatable topic.
If you have rheumatoid arthritis and are worried about your cancer risk, speak to your doctor about your concerns.