Lung cancer tumor is not serious if it grows up to 5cm without metastasis or invasion, but if it is accompanied by lymphatic and distal organ metastasis, the condition will be more serious. The severity of lung cancer is mainly determined by the stage and pathological type, not only by the size of the tumor. Although a 5cm tumor is large, if there is no metastasis or invasion, it still belongs to T2N0M0 stage, and it can be effectively controlled through radical surgery with radiotherapy and chemotherapy, and the condition is not very serious. If the tumor has metastasis in the lymphatic system and distal organs, then the condition is more serious and basically only chemotherapy, radiotherapy and targeted therapy can be taken to prolong the survival cycle of patients.