The recurrence rate of different stages and types of lung cancer is different, and the 3-year recurrence rate is around 10%-40%. Different stages of lung cancer have different prognosis, and early treatment has the best effect. Especially in recent years, after lung cancer screening, if lung cancer in situ is found and timely surgical resection is performed, more than 95% can be cured, and the chance of recurrence is relatively low, and the chance of recurrence in 3 years is about 10%-20%. In the middle and late stages, due to the relatively large tumor load, even if surgical resection is carried out, there may be residual tumor cells and recurrence and metastasis, and the chance of recurrence in 3 years after surgical resection is about 40%. Different types of lung cancer have different biological characteristics, and of course the degree of malignancy is also different. For example, small cell lung cancer with higher degree of malignancy has significantly higher recurrence probability because it is prone to recurrence and metastasis. It is recommended that patients should take active treatment and undergo regular postoperative checkups in order to detect lesions at an early stage and treat them at an early stage, so as to avoid delaying the condition.