ALK and non-small cell lung carcinoma: A young, non-smoking male diagnosed with ALK and EGFR-negative multifocal NSCLC showed disease progression after first-line erlotinib and developed genomic alteration in ROS1. The patient was treated with 250 mg crizotinib twice per day, which led to a significant improvement in patient-reported symptoms within 7 days and dramatic shrinkage of malignant lesions at imaging within 8 weeks [31].