Study On Micrometastasis In Peripheral Blood Of Non-small Cell Lung Cancer

[Objective] Using real-time fluorescence quantitative polymerase chain reaction (RT-QPCR) to find out the relative quality of CK-19 mRNA in peripheral blood of the NSCLC patients from the outcomes of part one, and discuss whether the method of detecting the expression of CK-19 mRNA in NSCLC can be a new way to diagnose micrometastasis of NSCLC and want to find out the best sensitivity and specificity and the cut of value under the best of the experiment.[Methods] (1) Compared with 50 patients with benign lung diseases and 50 healthy volunteers, we use centrifugal column method to extract total RNA and detect the expression of CK-19 mRNA via using RT-PCR in peripheral blood of 113 cases, and evaluate the relationship with clinicopathologic features, at the same time we use GAPDH as internal control. And put it under testing and statistical analysis. (2) On the base of the part one, we use GAPDH as internal control and Real-time fluorescence quantitative polymerase chain reaction (RT-QPCR) technology to detect the expression of relative levels of molecular marker ck-19mRNA in peripheral blood of 44 NSCLC patients. We use two ways to analyse the results. One is histogram, from that we can find out the relative quantities in different TNM; the other is Receiver operating characteristic curve(ROC curve), we can get the Area under the ROC curve(AUC) to determine cut-off value.[Results](1) The expressions rate of CK-19 mRNA in patients and the control group were 38.94%(44/113) and 1%(1/100), the diversity is significant in statistics (P< 0.05), and the expression of ck-19 is relative with TNM and Differentiation. (2) Using Receiver operating characteristic curve (ROC curve) to analysis of the expression of CK-19 mRNA shows that when the cut-off value is 0.2357, its sensitivity and specificity was 95.45% and 77.27% respectively, and the area under the ROC curve (AUC) is 0.896. [Conclusion] (1)Using high sensitivity RT-PCR technology to detect circulating tumour cells (CTCs) in peripheral blood of NSCLC patients is feasible. (2) CK-19 mRNA might be the specific and sensitive marker to detect circulating tumor cells in peripheral blood of NSCLC patients.(3) Using ROC curve to quantitative analysis of the expression of CK-19mRNA can be considered as a method when micrometastases in NSCLC patients, but it still needs further follow-up observation of a large sample volume to prove.