Decline in serum carcinoembryonic antigen and cytokeratin 19 fragment during chemotherapy predicts objective response and survival in patients with advanced nonsmall cell lung cancer

BACKGROUND. The authors assessed the predictive and prognostic role of decline in the serum levels of carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA 21-1) during chemotherapy in patients with advanced nonsmall cell lung cancer (NSCLC). METHODS. Changes in serum levels of CEA and CYFRA 21-1 during first-line, conventional chemotherapy were studied prospectively with an immunometric assay at baseline and every 2 courses in 117 patients with advanced NSCLC. Data were correlated with radiologic objective response (OR) and survival. RESULTS. One hundred seven patients were evaluable for radiologic and serologic response assessment after 2 chemotherapy courses. The radiologic OR rate was 44% overall. The CEA and CYFRA 21-1 responses (>= 20% reduction over baseline level; assessed after the second course of chemotherapy) were 38% and 61%, respectively. Statistically significant correlations were observed between CEA and CYFRA 21-1 responses and OR (P = .01 and P = .004, respectively). The median survival from response assessment (landmark analysis) was 9 months. In a univariate analysis, disease stage, performance status, baseline lactate dehydrogenase level (LDH), OR, CEA response, and CYFRA 21-1 response were correlated significantly with survival. In particular, the median survival was 13 months for patients who had a CEA response and 11 months for patients who had a CYFRA 21-1 response compared with 8 months and 6 months for patients who did not respond, respectively. In a multivariate analysis, performance status (P = .005), baseline LDH level (P = .02), CEA response (P = .03) and CYFRA 21-1 response (P = .01) were confirmed as independent prognostic factors for survival. CONCLUSIONS. CEA and CYFRA 21-1 responses appeared to be reliable surrogate markers of chemotherapy efficacy in patients with advanced NSCLC.