What happened, in summary

A 70-year-old man presented with chest pain and was found to have lung adenocarcinoma involving the pleura. Molecular testing identified an EGFR mutation, and he began gefitinib. He had an early partial response followed by a near-complete response that lasted for 5 years.

After five years on gefitinib, he developed dizziness and later fell. Brain imaging found metastases in the right temporal and left occipital regions while disease outside the brain remained controlled. Because tissue testing for the T790M resistance mutation was not feasible, its status remained unknown. He switched to osimertinib because of its ability to reach the brain.

After 3 months, the brain metastases had partially responded. He then received stereotactic radiation to both lesions, and follow-up imaging at 6 months showed a complete intracranial response. Osimertinib was continued. His course documents about 7 years living with metastatic EGFR-mutated lung cancer.