Lung cancer stage 3a is difficult to realize complete cure. Lung cancer stage 3a is based on the international TNM staging standard, which indicates that the patient has already had local lymph nodes and tissue infiltration and metastasis, and belongs to the locally advanced stage. Active treatment can help prolong the survival time of the patient, and the five-year survival rate of the patient stays around 20%, but it is difficult to realize a complete cure. Patients with stage 3a lung cancer can take surgical treatment, through which the lesion site is resected and the tissues around the lymph nodes are cleared at the same time, and a period of chemotherapy is also needed after the operation, so as to reduce the chances of recurrence and metastasis of the patients, and mainly prolong the survival time of the patients.