Clinical Applications Of Circulation Tumor Cells In Lung Cancer Patients

Objective:This study aimed to investigate the relationship between circulating tumor cells(CTCs) and clinicopathologic characteristics, chemotherapy efficacy and progression-free survival(PFS)of lung cancer patients.Methods:A total of 54 patients with histological diagnosis of lung cancer were enrolled, of which 32 cases were treated with cisplatin-based chemotherapy. CTCs count was performed, by using immunomagnetics and immunofluorescence methods, before chemotherapy and after two cycles.Results:1.Overall, 35(64.81%) patients had a positive CTC count at baseline, median CTC number was 2(range,0-51)CTCs/4ml of blood.2.The positive rate of CTCs in lung cancer patients with age<60 years old(86.4%)was significantly higher than that with age≥60 years old(50.0%)(P=0.006). The positive rate of CTCs in stage Ⅲ-Ⅳ group was 77.1% compared with 25.0% of stageⅠ-Ⅱ group(25.0%)(P=0.004). CTCs positivity in patients with regional lymph nodes metastasis(74.4%)was greater than that without regional lymph nodes metastasis(40.0%)(P=0.018). The prevalence of CTCs positivity was associated with distant metastasis(P=0.048), The positive rate of CTCs in patients with distant metastases(74.3%) was significantly higher than that without distant metastasis(47.4%). But CTCs positivity did not significantly differ according to gender, smoking history, pathological type and differentiation(P>0.05).3.The positive rate of CTCs(53.1%) decreased after chemotherapy compared with that before chemotherapy(75.0%), there have no statistically significant(P = 0.068).4.32 cases of lung cancer patients underwent two cycles of chemotherapy, the results of efficacy evaluation by CT examination showed PR 9 cases, SD 16 cases and PD 7 cases. After two cycles of chemotherapy, compared with CTCs count at baseline, the number of CTCs increased in 10 cases, unchanged in 5 cases and decreased in 17 cases. The correlation analysis showed that it was negative correlation between the number of CTCs change and chemotherapy efficacy(r =-0.540, P=0.001).5.For patients with a positive CTC, there was a significantly shorter median PFS(128days;95%CI,75.26-180.74days)compared to patients with a negative CTC(median PFS,253days; 95%CI,154.47-351.53days)( c2=10.480,P=0.001).Conclusions:1. The positive rate of CTCs was associated with age, TNM stage, regional lymph nodes metastasis and distant metastasis, but did not significantly differ according to gender, smoking history,pathological type and differentiation of lung cancer patients.2. We can predict chemotherapy efficacy of lung cancer patients by monitoring the changes of CTCs count before and after chemotherapy.3. CTCs have the prognostic value of evaluating the PFS of lung cancer patients.