EGFR and non-small cell lung carcinoma: Although the molecular status of EGFR in primary NSCLC has been extensively studied, the data on the molecular status of BM from NSCLC are limited.64, 65, 66, 67, 68, 69 Studies of molecular pathways that mediate brain metastases have shown that oncogenes play an important role and that the molecular statuses of these genes need to be further investigated because they can be part of the patient risk stratification.70