Rituximab in rheumatoid arthritis and the risk of malignancies: Report from a French cohort

Objective: To determine in real-life conditions the safety of treatment with rituximab (RTX) in patients with rheumatoid arthritis (RA) regarding malignancies. Methods: Analysis of safety data from a cohort of RA patients who received at least one course of RTX. RA patients with previous malignancies were followed-up and compared to the group of patients with no history of malignancy. Results: One hundred and eighty-six RA patients, 33 (17.7%) males, the mean age and disease duration were 55.8 +/- 13.0 and 14.5 +/- 11.1 years, respectively. The mean follow-up was 22.3 +/- 15.1 months, corresponding to a follow-up of 346 pt-years of RTX exposure. Among these, 24 (12.9%) patients had a history of a prior malignancy. Five cancers were diagnosed during follow-up with four new malignancies (1 prostate, 1 breast, 1 colon and 1 cervical cancers) and one recurrence of a known breast cancer. The overall cancer rate was 1.45/100 pt-years (95%CI: 0.19 to 2.70), which is comparable to previously studied DMARD-treated cohorts. No new hematopoietic neoplasms were reported and the six lymphomas that have been in remission prior to RTX-therapy remained under follow-up. The baseline demographic and disease characteristics and the cancer-risk of the 24 patients who presented with a prior malignancy were similar to those with no cancer history (162 patients). Conclusions: Although based on a modest number of observed cancers, and despite selection bias (12.9% of prior malignancies in our RTX treated RA), this observational study suggests that RTX does not increase the cancer risk in RA patients. (C) 2010 Societe francaise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved.