Rheumatic immune-related adverse events (irAEs) occur in 5% to 10% of patients with cancer who receive treatment with immune checkpoint inhibitors, according to a prospective observational study published in the Annals of Rheumatic Diseases.
Researchers from a single institution in France followed 524 adult patients who received immune checkpoint inhibitors from September 2015 to May 2017. Of these patients, 35 (6.6%) developed musculoskeletal symptoms and were referred to the Department of Rheumatology. With a median exposure time of 70 days, 34 patients had received treatment with antiprogrammed cell death protein 1 (PD-1)/PD-1 ligand 1 (PD-L1), and 1 received anticytotoxic T-lymphocyte-associated protein 4.
Inflammatory arthritis, mainly rheumatoid arthritis, polymyalgia rheumatica, and psoriatic arthritis, was diagnosed in 20 patients, and 15 patients presented with noninflammatory musculoskeletal disorders.
As a result, 19 patients were treated with glucocorticoids, 2 received methotrexate, and nonsteroidal anti-inflammatory drugs, analgesics, and physiotherapy were used to treat noninflammatory disorders. All but 1 patient continued treatment with an immune checkpoint inhibitor.
Compared with patients without irAEs, the tumor response rate was significantly higher in patients with rheumatic irAEs (35.3% vs 85.7%, respectively; P <.0001).
“Collaboration between oncologists and rheumatologists is worthwhile to achieve a better understanding of these rheumatic irAEs and to define appropriate treatment algorithms,” the study authors concluded.
Kostine M, Rouxel L, Barnetche T, et al.; on behalf of the FHU ARCONIM. Rheumatic disorders associated with immune checkpoint inhibitors in patients with cancer – clinical aspects and relationship with tumour response: a single-centre prospective cohort study [published online November 16, 2017]. Ann Rheum Dis. doi:10.1136/annrheumdis-2017-212257