MAP2K1 and lung cancer: A number of gene mutations previously reported with lung cancer were identified in CSF with NM, while EGFR, TP53, PTEN, TET2, APC, CDKN2A, GNAQ, NOTCH1, FLT3, VHL, BRCA2, PTCH1, CBL, MLH1, BRAF, NRAS, TSC2, CSF1R, KIT, MAP2K1, MSH2, TSC1, HRAS, IFITM1 and BCL9 mutations were statistically more common in the present cohort of NM, when compared to the lung cancer noted in the COSMIC database (https://cancer.sanger.ac.uk) (Table 3).