Targeted lung cancer treatment does not cause spread. Lung cancer can be divided into non-small cell lung cancer and small cell lung cancer according to histology; it can be divided into highly differentiated, moderately differentiated, poorly differentiated and undifferentiated tumors according to histological grading, among which undifferentiated and poorly differentiated tumors, small cell lung cancer and large cell lung cancer, often appear distant metastasis earlier. Targeted therapy is a treatment targeting the mutation site of tumor occurrence, which is effective for EGFR mutation, ALK-positive tumors and ROS1-positive tumors currently known to inhibit tumor growth and reduce distant metastasis. If metastasis occurs during the application of targeted drugs, it is not a drug effect, but a sign of drug failure. Therefore, during and after the treatment of lung cancer, regular review is needed to detect disease progression early and take new treatment measures.