Successful osimertinib treatment in a patient who exhibited intramedullary spinal cord metastases of lung adenocarcinoma with an acquired EGFR T790M mutation

Intramedullary spinal cord metastases (ISCMs) of non-small cell lung cancer (NSCLC) constitute a serious if infrequent complication, characterised by rapid progression of neurological deficits, with poor prognosis. We describe a 52-year-old man with ISCMs secondary to lung adenocarcinoma who acquired the T790M mutation of the epidermal growth factor receptor (EGFR) after previous use of a first-generation EGFR tyrosine kinase inhibitor (TKI); he was successfully treated with osimertinib. This is the first report of the use of osimertinib in ISCMs: due to its high central nervous system activity, osimertinib could be useful for treating ISCMs secondary to NSCLC in patients who exhibit the T790M mutation.