Objective To investigate the effect of crizotinib as targeted therapy on EML4-ALK expression in patients with non small cell lung cancer. Methods The clinical data of patients with non small cell lung cancer treated in our hospital from February 2010 to March 2016 were retrospectively analyzed. According to the treatment methods,they were divided into two groups: the traditional chemotherapy group and the targeted group. The targeted therapy group was given the targeted therapy of traditional Chinese medici...