Application Of Circulating Tumor Cells In The Diagnosis Of Pulmonary Nodules

objective: Objective to study the correlation between the number of circulating tumor cells in peripheral blood and the clinical relevance of lung cancer and its value in the diagnosis of lung cancer.Methods : From May 2016 to November 2016,we have collect a total of 89 patients with pulmonary nodules were examined by CT before in the Department of thoracic surgery of Sichuan Provincial People’s Hospital,and 3healthy volunteers 。 Peripheral blood 4ml was collected before operation to detect circulating tumor cells.by using immune-magnetic beads negative screening + targeted fluorescence quantitative PCR method the definition of circulating tumor cells in peripheral blood of patients with positive 8.7u/ml,the positive rate of the relationship between CTC and age,sex,pathological type,clinical stage and other common tumor biomarkers matter.The statistical analysis was processed by SPSS22.0 statistical software,measurement data using the mean and standard deviation(S)in the form of the normal distribution of data or transformed normal distribution data analysis,statistical analysis was performed using independent samples t test or variance;on normal distribution data,the the rank sum test;count data using frequency(%),chi square test was used for statistical analysis;p < 0.05,the difference was statistically significant.Receiver operating characteristic curve using Med Calc 11.4.2.0 analysis software(receiver operating characteristic curve,ROC curve)to assess the number of circulating tumor cell detection and clinical commonly used tumor markers for lung tumor detection sensitivity,specificity,with the area under the curve(area under,curve,AUC)to compare the number of circulating tumor cells detection and tumor markers on the accuracy of pulmonary nodules.The optimal Cutoff value of the marker is determined according to the correct index(Youden index).The difference was statistically significant with p<0.05.Results: A total of 92 sample were included in this study,in which there were 3healthy subjects,and the pathological diagnosis of lung cancer was performed in 65 cases.There were 24 cases of benign pulmonary lesions.The positive rate of CTC in patients with lung cancer was significantly higher than that in patients with benign pulmonary nodules and healthy subjects.The mean value of CTC in lung cancer was 13.61 ± 9.73u/3ml;the mean value of CTC was(5.02u/3ml)and the mean value of CTC in healthy subjects was 4.30 ±1.49u/3ml,the difference was statistically significant(p<0.001).The sensitivity of ROC detection of circulating tumor cells in the detection of lung nodules was 84.6%,the specificity was about 70.8%.Compared with CTC and commonly used tumor markers,the results showed that the AUC value of CTC was 0.804,which was higher than that of other tumor markers.The value of CTC in patients with lung squamous cell carcinoma was 14.83 ± 5.83u/3ml,the CTC value of lung adenocarcinoma patients was 12.7± 10.68u/3ml,and the CTC value of lung squamous cell carcinoma was higher than that of non adenocarcinoma patients,the difference was statistically significant(p=0.022).The value of CTC in patients with lymph node metastasis was 14.66 ±19.06u/3ml,and the CTC value of patients with lung cancer without lymph node metastasis was 12.49 ± 4.06u/3ml,the difference was statistically significant(p=0.012).The CTC value of the tumor with the largest diameter greater than or equal to 7cm was 18.99 ± 4.80,which was greater than the maximum diameter of the tumor was less than 7cm,the difference was statistically significant(p=0.005).The CTC value of patients with stage I-II lung cancer was 11.57 + 5.38u/3ml,a total of III-IV patients in stage,CTC value of 16.66 + 13.51u/3ml.The difference between the two groups was statistically significant(p=0.011).CTC values were not related to gender,smoking,and pathological differentiation.The sensitivity of ROC detection of circulating tumor cells to the detection of lung tumors,specificity(70.8%).Compared with CTC and commonly used tumor markers,the results showed that the AUC value of CTC was 0.804,which was higher than that of other tumor markers.Conclusion: Immunomagnetic negative screening + target detection of CTC fluorescence quantitative PCR method has good capability in diagnosis of lung cancer,the detection sensitivity of 84.6%;CTC value and the maximum diameter of tumor,pathological type,lymph node metastasis and patients with age related;with gender,smoking,and whether the differentiation degree of pathological staging of lung cancer.compared with the general tumor markers,detection sensitivity of CTC for lung cancer is higher;but some research into the group of small samples.