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 74-year-old woman without a history of smoking presented with a scalp mass. An incisional biopsy performed on the scalp mass revealed adenocarcinoma with CK-7 and TTF-1 positivity on immunohistochemical staining. An EGFR mutation analysis found an exon 21 L858R point mutation. Whole body PET-CT detected a lung mass and multiple bone metastases. Brain MRI identified several tiny enhancing nodules on both cerebral hemispheres. After 5 months of gefitinib treatment (250 mg/day), a follow-up brain MRI showed no brain parenchymal metastatic lesions (fig. ).