KRAS and lung carcinoma: Strikingly, a significant prognostic effect of KRAS status was found only in bone metastases by analyzing different subcohorts of lung cancer metastatic sites, including the lungs, bone, adrenal gland, brain, pleura and liver.7 The presence of KRAS mutation is related to markedly worse outcomes in bone metastatic cases.7,8 Currently, a few promising drugs targeting biomarkers in advanced metastatic lung cancer patients harboring various mutations are under investigation.