Immune Checkpoint Inhibitor-Induced Ocular Toxicity: A Case of Pembrolizumab-Associated Corneal Ulceration and Evisceration

Background and Clinical Significance: Immune checkpoint inhibitors (ICIs) ushered in a new era in cancer treatment, but alongside their efficacy is an adverse event profile that involves the immune system as a whole and may impact several organs. Case Presentation: We present the case of a 68-year-old woman with a diagnosis of cervical cancer treated with pembrolizumab who developed progressively steroid-refractory chronic diarrhea and ensuing visual problems. Topical antibiotics failed to heal a corneal ulcer in the left eye, necessitating evisceration. Imaging showed intestinal pneumatosis without ischemia, and there was immediate clinical improvement after initiation of corticosteroid therapy. This clinical picture—steroid-dependent colitis and immune-mediated uveitis associated with secondary bacterial infection—was coded as an immune-related adverse event (irAE) resulting from ICI treatment. Because of the prompt and complete regression of the symptoms upon corticosteroid therapy, this was considered as a criterion for the final diagnosis. Conclusions: The case highlights the complexity and potential severity of irAEs that need to be appropriately identified and promptly managed by multidisciplinary teams.