In RA, No Added Second Malignancy Risk With Biologics

For patients with rheumatoid arthritis who have a previous history of cancer, new research demonstrates that treatment with biologics does not increase the risk of a second malignancy. The findings were presented recently at the 2017 ACR/ARHP Annual Meeting in San Diego.

Because biologic disease-modifying antirheumatic drugs used to control rheumatoid arthritis disease activity and prevent joint damage suppress the immune system, there is concern that biologics could increase the risk of malignancy in patients with a history of cancer.

This concern has led to some reluctance to treat patients who have rheumatoid arthritis and a previous cancer diagnosis with biologics, leaving these patients to receive inadequate treatment of their arthritis.

The study
Researchers in Denmark led by Dr Lene Dryer, Associated Professor of Rheumatology at the University of Copenhagen, conducted a population-based cohort study to determine whether biologic use increases the risk of a second cancer diagnosis. The study also looked at mortality rates among these patients.

Patients with rheumatoid arthritis who had a primary cancer diagnosis were selected from the DANBIO Registry, a national medical records database in Demark, from 2000 to 2011. Of these patients, 190 received biologics only before their primary cancer diagnosis, 220 received biologics only after their diagnosis, 92 received biologics before and after their diagnosis, and 1176 never received biologics.

Researchers analyzed these cases to determine the hazard ratios (HRs) for secondary malignancy and death in this population.

The results
Among the 502 patients who received a biologic at any time, the HR for a second malignancy was 1.11. For those who were never treated with a biologic, the HR was 1.00.

Thus, researchers concluded that there was no significant increased risk of a second malignancy in patients with rheumatoid arthritis who had a history of cancer and were treated with biologics compared with those who never used biologics.

Researchers also examined the mortality rates for this population. After the data were adjusted for age, gender, calendar time, site of the cancer, and extent of the disease, the HR for death was 1.00 for those who were never treated with a biologic, 1.20 for those treated with a biologic only before their cancer diagnosis, 1.36 for those treated with a biologic only after their cancer diagnosis, and 1.22 for those who received biologics both before and after.
Researchers determined that no clear conclusions could be drawn concerning mortality in patients treated with biologics.

Implications for physicians
“It is reassuring that these results indicate no increased risk of a second malignancy in RA patients with a past cancer who used biologic therapy, and that there was no major indication of an increased mortality rate among users of these medications,” Dr Dreyer said in a press release. “Our data does provide some reassurance that biologics don’t pose an immediate danger in patients with a history of cancer.”

Still, Dr Dreyer suggested that these statistical analyses must be interpreted with caution because of the small number of patients in the study who had second malignancies and that more studies are required to confirm these findings.

References:

American College of Rheumatology Press Release. “Biologics Do Not Increase the Risk of Second Malignancy in Rheumatoid Arthritis Patients.” November 4, 2017.

Lene Dreyer, Cordtz R, Hnawn IM, et al. “Risk of Second Malignant Neoplasm and Mortality in Rheumatoid Arthritis Patients Treated with Biologic Dmards: A Danish Population-Based Cohort Study.” Abstract Number 11L, 2017 ACR/ARHP Annual Meeting; San Diego, California.