Two Cases of Sinusitis Induced by Immune Checkpoint Inhibition.

We report the acute onset of aseptic sinusitis in 2 patients receiving the immune checkpoint inhibitors, ipilimumab and nivolumab, for treatment of metastatic melanoma. Ipilimumab, a monoclonal antibody targeting cytotoxic T-lymphocyte antigen-4, and nivolumab, targeting programmed cell death-1, have been associated with numerous immune-related adverse events. To the authors' knowledge, this is the first report of aseptic sinusitis as a consequence of immune checkpoint inhibition therapy.