ROS1 and lung adenocarcinoma: They are represented by the ROS1 and RET gene rearrangements (about 1-2% of lung adenocarcinomas) and by the activating mutations of BRAF (V600E and others) and HER2. Also the FGFR1 and PDGFR amplification and the mutations of PI3KCA, PTEN and DDR2 could have future therapeutic implications, especially in squamous cell lung cancer.