Safety of Immune Checkpoint Inhibitors in Cancer Patients With Preexisting Autoimmune Vasculitis.

OBJECTIVE

Immune checkpoint inhibitors (ICIs) are effective cancer therapies but often cause serious immune-related adverse events (irAEs). Patients with preexisting autoimmune diseases, including vasculitis, are excluded from trials. We aimed to evaluate the frequency, severity, and outcomes of vasculitis flares and irAEs in this population.

METHODS

We performed a retrospective review of cancer patients with prior vasculitis treated with ICIs at our institution and conducted a literature search for additional cases. Data included baseline features, vasculitis flares, irAEs, treatments, and tumor response.

RESULTS

Twenty-five patients were identified (16 from our institution and 9 from the literature). Median age was 71 years; 13 (52%) were female. Vasculitis types included giant cell arteritis (GCA, n = 9), granulomatosis with polyangiitis (GPA, n = 8), eosinophilic granulomatosis with polyangiitis (EGPA, n = 2), leukocytoclastic vasculitis (n = 2), other cutaneous vasculitis (n = 2), and Henoch-Schönlein purpura and Behçet disease (1 each). Cancer types were diverse. Most patients received anti-programmed death-1 monotherapy (n = 17). Eight patients (31%) experienced a vasculitis flare after ICI initiation (2/9 GCA, 4/8 GPA, 2/4 cutaneous vasculitis). Flares occurred after a median of seven weeks. Treatment included glucocorticoids in seven patients, combined with biologic or cytotoxic agents depending on vasculitis type. Seven of eight flares resolved, and four patients continued ICI therapy. Three additional patients developed de novo irAEs: severe hepatitis (n = 1), grade 3 colitis (n = 1), and grade 3 autoimmune hemolytic anemia (n = 1), all improving with treatment. One patient with GCA died due to a flare; no deaths were attributed to de novo irAEs. Overall, more than one-third of patients achieved a favorable tumor response.

CONCLUSION

Nearly one-third of patients with preexisting vasculitis experienced a disease flare during ICI therapy, with one fatal case. For most, outcomes were favorable with effective flare management. Preexisting vasculitis should not be considered an absolute contraindication for cancer immunotherapy with ICI.