Retrospective cohort study of psoriasis risk with immune checkpoint inhibitors for cancer

Immune checkpoint inhibitors (ICIs) can improve oncological outcomes among patients with cancer, but are also associated with increased risk of immune-related adverse events, including the development of autoimmune diseases. A nationwide retrospective cohort study in Taiwan investigated the association of use of ICIs for cancer with the risk of psoriasis. Among 135.230 patients receiving antineoplastic medications for stage III or IV cancer, 3188 patients received ICIs. During 197,107 person-years of follow-up, 295 patients (0.2%) were diagnosed with psoriasis. The incidence of psoriasis was 5.76 per 1000 person-years among ICI users, compared with 1.44 per 1000 person-years among ICI nonusers. After adjusting for demographics and comorbidities, ICI users were found to have a 2-fold increase in their risk of developing psoriasis. The results were consistent and robust across all follow-up intervals and all sensitivity analysis. The authors conclude that among patients with cancer, treatment with ICIs was associated with increased risk of psoriasis.