The accuracy rate of gene mutation for lung cancer blood test is relatively high, but it is not as high as the diagnostic rate of gene test for tissue, so it is recommended to go to regular hospitals for testing. The purpose of genetic testing for lung cancer is to clarify whether there are gene mutations, because some patients develop lung cancer related to gene mutations, such as most patients with lung adenocarcinoma have mutations in driver genes, including AKT1, BRAF, EGFR, HER2, K-RAS, PIK3CA, MEK1, NRAS and other gene mutations and ALK gene fusion. For lung cancer patients with gene mutations, targeted drug therapy can be used to kill lung cancer cells in a targeted way, while reducing the damage to normal tissues, thus improving the therapeutic effect of lung cancer. For example, patients with EGFR mutation can be prioritized to be treated with erlotinib (EGFR-TKI) or gefitinib, and patients with positive ALK fusion gene can be given ALK inhibitor treatment. If a patient wants to take a genetic test to find out if he or she has a gene mutation, he or she should go to a regular hospital and see a specialist for a blood test. If the test result shows that there is a gene mutation, then targeted drug therapy can be carried out under the guidance of the doctor.