Incidence of overall and site-specific cancers in tnf inhibitor treated patients with psoriatic arthritis: a population-based cohort study from 4 nordic countries

Background Tumour necrosis factor inhibitors (TNFi) effectively reduce inflammation in Psoriatic arthritis (PsA). However, a possible association between treatment with TNFi and an increased cancer risk has previously been suggested.Objectives To investigate the risk of cancer in TNFi treated PsA patients compared with standardized rates from the general population in Denmark, Finland, Iceland and Sweden.Methods TNFi-treated PsA patients were followed from first registration with TNFi-treatment in ARTIS (Sweden), DANBIO (Denmark), ICEBIO (Iceland) or ROB-FIN (Finland) and linked to the national Cancer Registry in each country. Patients with a cancer history prior to start of follow-up were excluded. We investigated the risk of primary cancer among TNFi-treated PsA patients compared with general population cancer rates standardized to age, sex and calendar period within each country. Standardized incidence ratios (SIRs) were estimated for each country and pooled SIRs were subsequently calculated for both any cancer and site-specific cancers of interest.Results A total of 5218, 2039, 270 and 526 patients were registered as ever TNFi-treated in ARTIS, DANBIO, ICEBIO and ROB-FIN, respectively, contributing a total of 44 041 patient years of follow-up across all 4 countries.For all cancers, the SIRs of TNFi-treated patients from ARTIS, DANBIO, ICEBIO and ROB-FIN were 0.94 (0.80 to 1.10), 0.99 (0.77 to 1.26), 1.71 (0.88 to 2.99) and 1.28 (0.82 to 1.90), respectively. The number of observed and expected cancers and the SIRs of any and selected site-specific cancers are listed in table 1.View this table:Table 1 Standardized incidence ratios (SIR) of TNFi-treated patients from 4 Nordic countries compared with the general population.Conclusion Our results suggest that the overall cancer risk for TNFi-treated PsA patients is not increased compared to the general population. Further analysis of the risk of malignant lymphomas will inform on whether the increased risk we observed is attributed to the PsA disease or treatment with TNFi.Acknowledgement This study is funded by FOREUM and NordForsk.Disclosure of Interests Christine Ballegaard Speakers bureau: Janssen Pharmaceuticals., Karin Hellgren: None declared, René Cordtz: None declared, Bénédicte Delcoigne: None declared, Björn Gudbjornsson: None declared, Thorvardur Jon Love Consultant for: Received reimbursment from Celgene for speaking about guidelines for the treatment of psoriatic arthritis, Kalle Aaltonen: None declared, Dan Nordström Grant/research support from: MSD, Pfizer, Consultant for: AbbVie, BMS, MSD, Novartis, Roche, Pfizer, UCB, Speakers bureau: Novartis, UCB, Sella Aarrestad Provan Consultant for: Novartis, Speakers bureau: Lilly, Johan Askling Grant/research support from: Karolinska Institutet (JA) has or has had research agreements with the following pharmaceutical companies, mainly in the context of the ATRIS national safety monitoring programme for rheumatology biologicals: Abbvie, BMS, MSD, Eli Lilly, Pfizer, Roche, Samsung Bioepis, and UCB., Consultant for: Karolinska Institutet has received remuneration for JA participating in ad boards arranged by Lilly, Novartis, and Pfizer., Kristian Zobbe: None declared, Lars Erik Kristensen Grant/research support from: UCB, Biogen, Janssen Pharmaceuticals, and Novartis, Consultant for: Consultant for AbbVie, Amgen, Biogen, BMS, Celgene, Eli Lilly, Janssen Pharmaceuticals, MSD, Novartis, Pfizer, Roche, Sanofi, and UCB Pharma., Speakers bureau: Pfizer, AbbVie, Amgen, UCB, BMS, Biogen, MSD, Novartis, Eli Lilly and Company, and Janssen Pharmaceuticals, Lene Dreyer Consultant for: MSD, UCB and Janssen Pharmaceuticals, Speakers bureau: MSD, UCB and Janssen Pharmaceuticals, Speakers bureau: UCB, MSD, Eli Lilly and Janssen Pharmaceuticals.