Significance of neuron-specific enolase (NSE) in the diagnosis of bronchial carcinomas and neuroendocrine tumors

Abstract

The diagnostic significance of neuron-specific enolase in serum was examined in 54 patients with bronchial carcinoma and in 28 with neuroendocrine tumors. Control groups were 42 patients with epithelial and 39 with nonepithelial malignant neoplasms as well as 40 patients with benign pulmonary diseases. The sensitivity of neuron-specific enolase in small-cell bronchial carcinoma was 60% and increased to 87.5% in advanced stages ("extensive disease"). On the other hand, non-specific enolase showed an increase in only 13.8% of patients with other than small-cell bronchial carcinoma. The proportion of false-positive enolase values in non-malignant pulmonary diseases was 5%. Some endocrinal tumors (e.g. tumors of the APUD cell system) showed pathological serum concentrations in 7.1% of the cases only. 37.5% of epithelial malignant neoplasms had enhanced levels, but only 5.1% in nonepithelial neoplasms. Small-cell bronchial carcinoma is most probably present in patients with bronchial carcinoma and neuron-specific enolase serum concentrations above 25 micrograms/l.