ERA OF PERSONALISED MEDICINE IN METASTATIC ADENOCARCINOMA LUNG: Stage IV adenocarcinoma is not a single disease. Different molecular subtypes of NSCLC have been identified and the treatment approach is different for each subtype. The different molecular type include mutation in different receptors 1) EGFR mutation. 2) ALK 3) ROS 4) Met 5) b-raf 6) her2 nu In the list above top 3 mutation are most relevant in clinical practice and NGS ( next generation sequencing) can be used to identify other targetable mutations particularly in non smoker patients. In addition now with the availability of immunotherapy newly diagnosed stage IV adenocarcinoma with PDL1 >50% pembrilozumab is an option instead of chemotherapy. In addition the combination of chemotherapy(pemetrexed carboplatin) with pembrilozumab, irrespective of PDL1 , is one of the treatment option for stageIV NSCLC without driver mutation based on one of the keynote trials.