O6. Circulating tumor cells in the peripheral blood predict poor prognosis in surgically treated non-small cell lung cancer patients

Abstract

Objectives

Biomarker measurements of minimal systemic disease have the potential to monitor the molecular status of lung carcinomas without invasive tumor biopsy at the time of treatment selection. The real-time reverse transcription polymerase chain reaction (qRT-PCR) is a valuable analytical tool for the detection of circulating tumor cells (CTCs) in the peripheral blood. The aim of this study was to investigate whether the detection of mRNA-positive CTCs could be useful for predicting disease recurrence, disease-free survival (DFS), and cancer specific survival (CSS) in NSCLC patients undergoing surgery.

Methods

We used real-time RT-PCR for absolute gene expression quantification of carcinoembryonic antigen (CEA, CEACAM5, NM004363), epidermal growth factor receptor 1 (EGFR1, NM 005228), lung specific X-protein (LUNX, PLUNC, NM016583) and hepatocyte growth factor receptor (c-met, MET, NM 000245) in the peripheral blood in a group of 129 patients with surgically treated non-small cell lung cancer.

Results

The detection of CEA mRNA-positive CTCs in peripheral blood was associated with shorter DFS (P<0.009; HR=2.64, 95% CI: 1.24-5.62), and CSS (P<0.007; HR=2.73, 95% CI: 1.28-5.81). CTCs status measured using EGFR, LUNX and c-met mRNA individually did not show any significant clinical relevance.

Conclusions

The role of CTCs in prognostication in non-small cell lung carcinoma (NSCLC) patients is controversial, but may be better defined with advancing technologies of detection of such cells with higher precision, and improved clinical-pathological correlations. Detection of CEA mRNA-positive CTCs in the peripheral blood after surgery in patients with stage I-IIIA NSCLC is highly predictive for DFS and CSS. This technique may be useful for identifying high-risk patients among surgically treated NSCLC cases.