Complete Remission of Brain Metastases in Non-Small Cell Lung Cancer Patients Harboring an EGFR Mutation Treated with Tyrosine Kinase Inhibitor without Radiotherapy: A Report of 3 Cases
A 60-year-old man with a history of smoking presented at our hospital due to back pain and a chest X-ray abnormality. Lung adenocarcinoma was diagnosed with a bronchoscopic biopsy, and whole body positron emission tomography-computed tomography (PET-CT) showed multiple metastases on the lumbar spine and pelvic bone. The tumor was found to have an EGFR mutation (exon 19 deletion) and sequential brain magnetic resonance imaging (MRI) revealed multiple tiny enhancing nodules in the left occipital lobe and cerebellum. Gefitinib (250 mg/day) was administered and radiotherapy was performed on the lumbar vertebra. WBRT was deferred due to the absence of symptoms. One month after gefitinib treatment was initiated, interval regression of BM was identified on a follow-up brain MRI. After another 3 months, metastatic lesions were not discernible on a follow-up brain MRI (fig. ).