What happened, in summary

A 60-year-old woman had been treated for small-cell lung carcinoma in 2005 with chemotherapy, local thoracic radiotherapy, and prophylactic cranial irradiation to 50 Gy. Twelve years later, while the cancer remained in remission, she developed sudden global aphasia, lethargy, severe left-sided headache, and later right-sided weakness and seizures. Initial CT, cerebrospinal fluid testing, and repeated EEGs did not show an acute stroke, infection, or clear epileptiform activity. MRI revealed left parieto-occipital cortical changes compatible with stroke-like migraine attacks after radiation therapy, known as SMART syndrome, a delayed complication of brain irradiation. Multiple antiseizure medicines, high-dose methylprednisolone, and intravenous immunoglobulin did not produce early improvement. Her consciousness declined, and she required intensive-care sedation to induce an EEG burst-suppression pattern. After sedation was stopped, her consciousness and social interaction began to return. She left intensive care after 30 days and was later discharged to rehabilitation as aphasia and weakness improved. Five months after discharge, she had recovered almost completely, with only mild motor aphasia and difficulty walking. Her lung cancer remained in remission. The neurologic crisis was managed as a treatment-related late effect rather than recurrent cancer.