KRAS and non-small cell lung carcinoma: The most frequently observed primary was non-small cell lung carcinoma for 40 patients (62.5%), with adenocarcinoma histopathology (37 patients, 57.8%), and 13 patients carried a KRAS mutation, 3 patients an EGFR mutation and 1 patient carried an ALK translocation, found either in the biopsy of the primary or the histology analysis of the brain metastasis (Table 1).