Prognostic impact of cytological fluid tumor markers in non-small cell lung cancer

The serum tumor markers CYFRA 21-1, carcinoembryonic antigen (CEA), and squamous cell carcinoma antigen (SCCA) are useful in diagnosis and prognosis of non-small cell lung cancer (NSCLC). Cytologic tumor markers obtained during needle aspiration biopsies (NAB) of lung lesions are useful for NSCLC diagnosis. This study investigated the incremental prognostic value of cytologic tumor markers compared to serum tumor markers. This prospective study included 253 patients diagnosed with NSCLC by NAB with cytologic tumor marker analysis. Levels of cytologic CYFRA 21-1, CEA, SCCA, and their serum counterparts were followed up for survival analysis. Optimal cutoff values for each tumor marker were obtained for overall survival (OS) and progression-free survival (PFS) analyses. All patients were followed up for a median of 22.8 months. Using cutoff values of 0.44 ng/ml for C-SCCA, 2.0 ng/ml for S-SCCA, and 3.3 ng/ml for S-CYFRA, a multivariate analysis revealed that high S-SCCA (hazard ratio, HR, 1.84) and high C-SCCA (HR, 1.63) were independent predictive factors of OS. The 3-year overall survival rate was 55 vs. 80 % for high and low C-SCCA, respectively. Cytologic tumor marker level detection is easily obtainable and provides prognostic information for NSCLC. Cytologic tumor markers provide comparable prognostic information relative to serum tumor markers, with C-SCCA acting as a strong prognostic factor of overall survival and PFS.