Symptomatic aseptic sinusitis induced by immune checkpoint inhibitors for metastatic melanoma treatment.

Immune-mediated sinusitis is poorly described and may easily go undiagnosed. We conducted a retrospective, multicenter, national study focusing on symptomatic immune-mediated sinusitis in patients receiving immune checkpoint inhibitors (ICIs) for melanoma treatment. Twelve patients were included (50% women, median age 58 years). Overall, the paraclinical assessment, the inefficacy of antibiotic/antihistaminic treatment, the improvement of symptoms on immunosuppressants and/or after ICI discontinuation, and the presence of multiple concomitant immune-related adverse-events, suggested a noninfectious etiology. Recognizing this toxicity is imperative for limitation of diagnostic wandering and appropriate treatment. However, additional epidemiological studies are needed to assess its prevalence as a potential immune-related adverse-event, and its prognostic value in patients treated with ICIs.