Only a minority of patients with rheumatologic diseases who were exposed to modern cancer immunotherapy experienced a flare of their preexisting rheumatologic disease or any other immune-related adverse effects (IRAE), a recent study found. A retrospective medical record review was performed to identify all patients who received checkpoint inhibitor therapy at Mayo Clinic, Rochester, NY, between 2011 and 2016 (~5,200). Those with preexisting rheumatologic disease were identified using specific diagnostic codes. 16 patients were identified (81% female, median age 68.5). Researchers found:

• The most common rheumatologic diseases were rheumatoid arthritis (RA) (5), polymyalgia rheumatica (5), Sjogren's syndrome (2), and systemic lupus erythematosus (2).
• 7 patients were receiving immunosuppressive therapy or glucocorticoids for their rheumatologic disease upon initiation of a checkpoint inhibitor.
• In most cases checkpoint inhibitors were offered only after failure of several other therapies.
• IRAE occurred in 6 patients and all were treated successfully with corticosteroids and discontinuation of therapy.
• There were no significant differences in time from cancer diagnosis to immunotherapy, duration of immunotherapy, age, or sex between the patients with and without IRAEs.