Background Tumor necrosis factor alpha (TNF-a) is a key member of a large family of cytokines and receptors that are crucial to cellular organization. The development and use of biological therapy in the last several years, such as the TNF-a antagonists, has opened new perspectives for the treatment of patients with spondyloarthropathy (SpA). Nevertheless, it is now clear that TNF plays a paradoxical role in the evolution and treatment of malignant disease and the occurrence of malignancy has been considered as a possible adverse event in anti-TNF therapy.
Objectives To report systematically the malignancy incidence seen in a large cohort of patients with SpA treated with one or more anti-TNF therapies and to compare the results with the malignancy incidence in the global population.
Methods 231 patients with SpA that were treated with one or more anti-TNF therapies were included in a prospective observational cohort study for a total of 1199,83 patient years follow-up. The primary outcome for this study was the incidence of malignancy after starting anti-TNF treatment. Incidence rates were compared with the incidence rates of malignancy in Belgium by the Belgian Cancer Registry in the age group of 45-50 year old population in 2006.
Results In our study population, 6 out of 231 patients (2,6%) developed a malignancy after the start of anti-TNF treatment. The overall incidence rate of malignancy is 500,1 per 100000 patient years. Incidence rate for malignancy in female SpA patients is more than two-fold higher than that in males, but standardised incidence ratios are similar for male and female patients and indicate a higher incidence of malignancy in our study population compared to the control population
Conclusions Allthough there are certain study weaknesses, we can see a tendency towards a higher incidence of malignancy in SpA patients that are treated with anti-TNF therapy. It is still not clear whether this is a disease-related risk or a treatment-related risk.
Disclosure of Interest None Declared