Clinical significance of circulating tumor cells in squamous cell lung cancer patients.

Abstract

Squamous cell carcinoma (SCC) of the lung represents 20-30% of non-small cell lung cancers (NSCLC) and is associated with a poor prognosis. This study aims to investigate the presence of circulating tumor cells (CTCs) in squamous cell lung cancer patients and what its role might be in providing prognostic information. Serial blood samples from 100 patients both before and after initiation of one cycle of standard chemotherapy were analyzed using CellSearch system. Of 105 patients enrolled, 100 were evaluable. ≥ 2 CTCs per 7.5 mL of blood were present in 29% of patients at baseline before chemotherapy, and 9% patients have more than 5 CTCs. Based on the current literature, the CTC measurements were dichotomized as 2-4 versus ≥ 5 CTCs. In the univariate analysis, CTC count ≥ 5 at baseline and CTC count ≥ 5 at both time points (before and after one cycle of chemotherapy) were significantly associated with a poor PFS and OS outcome. Both factors remained independent poor prognostic markers in the stepwise multivariate analysis. Our study indicate that the CTC count is a prognostic factor for PFS and OS outcomes in Chinese patients with locally advanced SCC of the lung.