ROS1 and non-small cell lung carcinoma: At the time of the initial diagnosis, the incidence of brain metastases in the ROS1‐positive NSCLC patients we studied was only 15.7%, which is lower than that of patients with ALK‐rearranged NSCLC.19, 20, 21 For first‐line therapy, in patients treated with crizotinib treatment, disease progression in the brain showed a significant difference between the different ROS1 fusion variants (P < .05); 33.3% of patients in the non‐CD74 variant group had intracranial progression, as compared with only 5.9% of those in the CD74 variant group.