Vogt-Koyanagi-Harada-Like Uveitis Secondary to Pembrolizumab in Metastatic Gastric Cancer: A Case Report and Review of the Literature.

Introduction: Vogt-Koyanagi-Harada (VKH) disease is a multisystem syndrome characterized by uveitis and exudative retinal detachments in the absence of ocular trauma or surgery. Neurological and cutaneous manifestations can also occur. Prior case reports have associated immune checkpoint inhibitors with a VKH-like disease. Case Presentation: A 64-year-old woman presented with 3 months of epigastric pain, and subsequent endoscopy showed a large mass in the gastroesophageal junction. Staging imaging showed an FDG-avid para-aortic node, making the disease stage IV, and she was treated with systemic therapy with FOLFOX. Molecular profiling showed HER2 amplification and PDL1 positivity, so trastuzumab and pembrolizumab were added. PET and esophagogastroduodenoscopy with biopsies showed a complete radiologic and pathologic response to treatment. Chemotherapy was stopped, and she continued on trastuzumab and pembrolizumab maintenance. After about 18 months of treatment with pembrolizumab, she presented with painful blurry vision in both eyes. Ophthalmologic evaluation showed panuveitis, serous retinal detachment, bilateral uveal edema, and secondary angle closure, consistent with VKH-like uveitis. She was treated with local and systemic corticosteroids. Pembrolizumab was assessed as the most likely causative agent and was discontinued. Her ophthalmologic exam improved, and her visual acuity returned to baseline. She continues on trastuzumab maintenance, and most recent imaging shows no evidence of disease. Conclusion: Oncologists should be aware of VKH-like disease as a possible immune-related adverse event and seek urgent ophthalmologic consultation when such symptoms arise.