More recently, an intriguing report by Tsai et al. has suggested that the EGFR-L858R mutation (which is a common driver of NSCLC) fosters the spread of lung adenocarcinoma cells to the pleural space via activation of the CXCL12/CXCR4 axis [44]. The gene discussed is CXCL12; the disease is non-small cell lung carcinoma.