Management of MOG antibody-associated disease by pembrolizumab and radiation myelopathy in an elderly patient: A case report and literature review.

Immunotherapy and radiotherapy are important means for treating solid tumors. Both treatment methods can potentially cause neurologic injuries. Timely identification, diagnosis, and early treatment play a crucial role in the recovery from neurologic damage. This case report describes a 69-year-old woman with esophageal and oropharyngeal cancer who developed neurological complications after radiotherapy and immunotherapy. She experienced radiation-related motor impairment and symptoms returned after treatment with bevacizumab and corticosteroids. Later, she developed a rare demyelinating neuropathy, diagnosed as MOG antibody-associated disease (MOGAD), likely triggered by immune checkpoint inhibitors, which is a very rare adverse drug reaction. Her condition improved with cessation of immunotherapy and the administration of steroid pulse therapy. Despite treatment interruptions due to side effects, her survival period was favorable, suggesting that reduced-dose therapy in elderly patients may not diminish its antitumor effect. This case emphasizes the need for vigilance in recognizing rare complications and rational antitumor treatment intensity in geriatric oncology.