How comparable are rates of malignancies in patients with rheumatoid arthritis across the world? A comparison of cancer rates, and means to optimise their comparability, in five RA registries

摘要

Background The overall incidence of cancer in patients with rheumatoid arthritis (RA) is modestly elevated. The extent to which cancer rates in RA vary across clinical cohorts and patient subsets, as defined by disease activity or treatment is less known but critical for understanding the safety of existing and new antirheumatic therapies. We investigated comparability of, and means to harmonise, malignancy rates in five RA registries from four continents.