Optic Perineuritis Associated with Nivolumab Treatment for Non-Small Cell Lung Cancer.

We report the case of a 54-year-old man who was treated with nivolumab for recurrent squamous cell lung cancer. After 7 cycles of nivolumab treatment, the patient presented to our hospital with right eye vision loss. Gadolinium-enhanced magnetic resonance imaging of the brain showed enhancement around the optic nerve sheath. This finding and his symptoms led to the diagnosis of optic perineuritis (OPN). Steroid pulse therapy was administered twice although there was no remarkable improvement in his visual field defect. The relationship between OPN and nivolumab is unclear. However, immune-related adverse events caused by immune checkpoint inhibitors should be considered.