TNF Inhibitors Do Not Increase Overall Cancer Risk in Psoriatic Arthritis

Individuals with psoriatic arthritis (PsA) who receive treatment with tumor necrosis factor (TNF) inhibitors do not have an increased risk of cancer compared with the general population, according to study findings presented at the Annual European Congress of Rheumatology.

The researchers followed individuals with PsA who were registered to have received treatment with TNF inhibitors in Sweden (n=5218), Denmark (n=2039), Iceland (n=270), and Finland (n=526). These data were linked to national cancer registries in each country.

The risk of primary cancer among participants with PsA was compared with the general population’s cancer rates; the rates were standardized to age, sex, and calendar period within each country.

The total patient-years of follow-up was 44,041 across all 4 countries.

The standardized incidence ratio (SIR) for all cancers among the participants with PsA was 0.94 (95% CI, 0.80-1.10) for those in Sweden; 0.99 (95% CI, 0.77-1.26) in Denmark; 1.71 (95% CI, 0.88-2.99) in Iceland; and 1.28 (95% CI, 0.82-1.90) in Finland. These findings suggested that the rate of all cancers was not significantly different among TNF inhibitor users with PsA than in the general population.

The researchers observed a statistically significant increase in malignant lymphomas during the study, with an SIR of 1.84 (95% CI, 1.20-2.82). However, the researchers noted it was unclear whether the increase was due to PsA or TNF inhibitor treatment.

“Further analysis is needed to assess whether the observed increase in malignant lymphomas is due to the psoriatic arthritis disease or the TNFi treatment,” study coauthor Lene Dreyer, a clinical professor at Aalborg University Hospital, Aalborg, Denmark, said in a press release.

—Melinda Stevens

References:

1. Ballegaard C, Hellgren K, Cordtz R, et al. Incidence of overall and site-specific cancers in TNF inhibitor treated patients with psoriatic arthritis: a population-based cohort study from 4 Nordic countries [EULAR OP0005]. Ann Rheum Dis. 2019;78(suppl 2):A67. https://scientific.sparx-ip.net/archiveeular/?view=1&c=a&searchfor=OP0005&item=2019OP0005. Accessed June 13, 2019.
2. No link between cancer and tumour necrosis factor inhibitor (TNFi) use in psoriatic arthritis [press release]. Madrid, Spain: Annual European Congress of Rheumatology; June 13, 2019. https://www.eular.org/sysModules/obxContent/files/www.eular.2015/1_42291DEB-50E5-49AE-5726D0FAAA83A7D4/02_abstract_op0005_tnfi_and_cancer_in_psoriatic_arthritis_final.pdf. Accessed June 13, 2019.