Clinical Correlation Between Circulating Tumor Cells And The Progression And Prognosis Of Lung Cancer

Background:Lung cancer is one of the leading causes of cancer-related mortality worldwide,with an estimated 1.8 million new cases every year.It is also the malignant tumor with the fastest increasing incidence in China in the past 30 years.Extremely low early diagnosis rates lead to the majority of patients being diagnosed late,and even those who receive early diagnosis and surgical treatment have a high recurrence rate,with a 5-year survival rate of only 19%.If lung cancer can be diagnosed earlier,postoperative recurrence and treatment effects can be more timely and comprehensively evaluated,the overall treatment effect of lung cancer will be greatly improved.Circulating tumor cells are general term for all kinds of tumor cells in the peripheral blood,which enter the peripheral blood circulation due to exfoliation from solid tumor lesions spontaneously or through invasive manipulation.There are three subtypes:epithelial CTCs,mesenchymal CTCs and mixed CTCs.A large number of studies have confirmed that the presence of CTCs in peripheral blood is an important marker of tumor diffusion from the primary site and an negative prognostic factor,leading to tumor recurrence and metastasis.Objective:To explore the influencing factors of peripheral blood circulating tumor cells in lung cancer patients and the relationship with serum tumor markers such as CEA and SCC.To analyze the correlation between circulating tumor cells and the progression and prognosis of lung cancer.Methods:90 lung cancer patients were enrolled in this study from January 2015 to May 2018 in the department of cardiothoracic surgery,zhujiang hospital of southern medical university,blood samples were collected on the first day after surgery,after two courses of first-line chemotherapy and during targeted therapy,to analyze CTCs and detecte the tumor makers such as CEA and SCC.Patients were followed up regularly until August 31,2019,with disease recurrence,progression,metastasis or death as the endpoint,and disease progression and time of death were recorded.In case of recurrence/metastasis,CTCs,CEA and SCC were detecte d again.All results were carried on statistical analysis.Results:(1)in 90 cases of lung cancer,the detection rate of circulating tumor cells was 91.1%,and the rate of CTCs>5 was 43.3%;(2)Circulating tumor cells were correlated with ki-67 expression,M stage and treatment method,the difference was statistically significant(all P<0.05);Patients with higher ki-67 expression and distant metastasis had higher CTCs positive rates,and those who were treated with chemotherapy had higher CTCs than patients treated with surgery;(3)Epithelial CTCs were related to N stage,differentiation degree,ki-67 expression and SCC level,and the mixed CTCs were related to N stage and treatment method,the difference was statistically significant(all P<0.05).However,there was no correlation between mesenchymal CTCs and clinical characteristics of lung cancer patients,with no statistically significant difference(P>0.05);(4)with disease progression or recurrence,CTCs(4.57 vs.8.57,P=0.000),especially epithelial CTCs(1.11 vs.3.14,P=0.017),were significantly higher than before,and CEA level increased markedly(59.15 vs.155.97,P=0.001),the difference was statistically significant;(5)TNM Stage,CTCs and gender were the factors influencing the recurrence/progression of lung cancer,and the difference was statistically significant(all P<0.05);CTCs,TNM stage and SCC level were negatively correlated with PFS in lung cancer patients,with statistically significant difference(all P<0.05).Patients in the CTCs positive group had a higher risk of recurrence/progression than those in the negative group;HR=2.127(95%CI:1.032-4.383);The higher TNM stage,the higher risk of recurrence/progression,HR=1.744(95%CI:1.274-2.387);Patients with higher SCC levels had a higher risk of recurrence/progression than patients with lower SCC levels,,HR=1.107(95%CI:1.039-1.180).Conclusion:Circulating tumor cells are closely connected with the recurrence/progression and prognosis of lung cancer.Real-time dynamic analysis of CTCs can help monitoring their condition,evaluate the efficacy and predict the prognosis of patients with lung cancer,ultimately improve their prognosis.