Neuroendocrine Markers-Useful Predictors of Therapeutic Responses in Non-resectable Non-small Cell Lung Cancer

Abstract

Objective: This study correlates the neuroendocrine (NE) markers neuron-specific enolase (NSE), chromogranin A (CGA), and synaptophysin (SYN) with the therapeutic responses and the survival times of patients with non-resectable non-small cell lung cancer (NSCLC). Method: One hundred twenty-six patients (male 64%, female 36%) with histopathologically confirmed NSCLC, treated with combination chemotherapy and radiotherapy in 1 center, underwent immunohistochemical analyses. Results: Thirty-nine patients (31%) were positive for NSE, 24 (19%) for Chr A, and 27 (21%) for SYN. Favorable therapeutic responses (partial and complete responses [CR]) were significantly greater in patients expressing NSE, Chr A, and SYN (P<0.05). There was a significant correlation between the therapeutic response and the percentage of NE-positive tumor cells (P<0.05). Tumors with greater than 25.5% NSE-positive cells can be predicted to have a favorable therapeutic response (94% sensitivity, 100% specificity). Patients with multiple markers were also more likely to have a favorable response compared to those with only 1 marker (59% compared with 38%) (P<0.05). Those with positive NE expression had significantly better 1- and 2-year survival compared with non-expressers (60% compared with 18%, P<0.001, and 33% compared with 0% P=0.000, respectively). Conclusion: Patients expressing the NE markers NSE, Chr A, and SYN, and those with a larger proportion of positive tumor cells have better therapeutic responses and longer survival times. © 2012 by The American Society for Clinical Pathology.