肺癌是目前世界上恶性肿瘤死亡的首要原因,且其发病率和死亡率呈上升趋势,由于其病因和发病机制复杂,目前尚缺乏有效的预防措施。肺癌诊断方法很多,但各自具有自己的优缺点,探索早期肺癌的诊断方法尤为重要。近90%的肺癌病人于发病年内死亡,全球平均5年生存率为11%,我国为8%[1] Lung cancer is the leading cause of death of malignant tumors in the world at present, and its morbidity and mortality are on the rise. Due to its complicated etiology and pathogenesis, there are currently no effective preventive measures. There are many ways to diagnose lung cancer, but each has its own advantages and disadvantages. It is particularly important to explore the diagnostic method of early stage lung cancer. Nearly 90% of lung cancer patients die during the year of onset, with an average global 5-year survival rate of 11% and 8% in China [1]