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 (> or =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.