Pathologic Correlation of Serum Carcinoembryonic Antigen and Cytokeratin 19 Fragment in Resected Nonsmall Cell Lung Cancer

BACKGROUND This study focused on the association between preoperative serum carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (Cyfra 21-1) levels and pathologic parameters in patients with resected non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS The records of 527 patients who underwent pulmonary resection of NSCLC were reviewed. The association between preoperative serum CEA and Cyfra 21-1 levels and variables that had p-values of less than 0.05 in a t-test or one-way analyses of variance was analyzed by multiple linear regression. RESULTS The mean serum CEA and Cyfra 21-1 levels prior to surgery were 6.8±23.1 mg/dL (range, 0.01 to 390.8 mg/dL) and 5.4±12.3 mg/dL (range, 0.65 to 140.2 mg/dL). The serum CEA levels were associated with tumor (T) and lymph node (N) stage and histology. The serum Cyfra 21-1 levels were associated with T stage, tumor size, and histology. Multiple linear regression indicated that serum CEA levels were associated with T (T3/4 vs. T1: β=8.463, p=0.010) and N stage (N2/3 vs. N0: β=9.208, p<0.001) and histology (adenocarcinoma vs. squamous cell: β=6.838, p=0.001), and serum Cyfra 21-1 levels were associated with tumor size (β=2.579, p<0.001) and histology (squamous cell vs. adenocarcinoma: β=4.420, p=0.020). CONCLUSION Serum CEA level was correlated with T and N stage, and Cyfra 21-1 with tumor size. CEA and Cyfra 21-1 showed histologic correlation. CEA is mainly elevated in adenocarcinoma and Cyfra 21-1 in squamous cell carcinoma. These results might be helpful for predicting pathologic status in preoperative NSCLC.