Mutations in the EGFR tyrosine kinase domain define a new molecular type of lung carcinoma, more frequent in particular subsets of patients. The SSCP assay is a rapid and reliable method for the detection of EGFR kinase domain mutations in lung cancer.

We report for the first time to our knowledge that V600E and non-V600E BRAF mutations affect different patients with NSCLC. V600E mutations are significantly associated with female sex and represent a negative prognostic factor. In addition, we identified a number of other clinicopathologic parameters potentially useful for the selection of patients carrying BRAF mutations.

A B S T R A C T PurposeTo investigate the prognostic role of genomic gain for MET and epidermal growth factor receptor (EGFR) genes in surgically resected non-small-cell lung cancer (NSCLC). Patients and MethodsThis retrospective study included 447 NSCLC patients with available tumor tissue from primary lung tumor and survival data. EGFR and MET status was evaluated by fluorescent in situ hybridization (FISH) in tissue microarray sections. ResultsEGFR FISH results were obtained in 376 cases. EGFR gene amplification and high polysomy (EGFR FISHϩ) were observed in 10.4% and 32.4% of cases, respectively. EGFR FISH-positive patients had a nonsignificant shorter survival than EGFR FISH-negative patients (P ϭ .4). Activating EGFR mutations were detected in 9.7% of 144 stage I-II disease with no impact on survival. MET FISH analysis was performed in 435 cases. High MET gene copy number (mean Ն 5 copies/cell) was observed in 48 cases (METϩ, 11.1%), including 18 cases with true gene amplification (4.1%). METϩ status was associated with advanced stage (P ϭ .01), with grade 3 (P ϭ .016) and with EGFR FISHϩ result (P Ͻ .0001). No patient with activating EGFR mutation resulted METϩ. In the whole population, MET-positive patients had shorter survival than MET-negative patients (P ϭ .005). Multivariable model confirmed that MET-negative patients had a significant reduction in the risk of death than MET-positive patients (hazard ratio, 0.66; P ϭ .04). ConclusionMET increased gene copy number is an independent negative prognostic factor in surgically resected NSCLC. EGFR gene gain does not impact survival after resection.