Neuron-specific enolase (NSE) in small-cell lung cancer: longitudinal tumor marker evaluation

Abstract

A study of 362 serum samples from 57 patients with small-cell lung cancer (SCLC) limited disease, enabled the validity of neuron-specific enolase (NSE) to be redefined as a serum parameter for therapy control. In contrast to standard calculation of sensitivity and specificity, the dynamics of marker development were incorporated in calculations by longitudinal evaluation of NSE values in the course of the disease. In this way, it was shown that sensitivity of the marker at 87% and specificity at 94% are clearly higher than reported to date. Longitudinal evaluation of the marker prevents interpretation errors that distort the outcome of sensitivity/specificity calculations for an early increase or decrease during remission or progression. Isolated false positive values are rare, solitary in the course of the disease and never exceed 35 μg/1. After radical surgery for so far untreated SCLC, the marker drops to normal values within nine to 14 days. Following chemotherapy NSE falls to normal values in 66% of all cases, even when radiologically there is only a partial remission. A correlation of changes of NSE level with certain types of therapy, for example NSE increase due to enhanced release by nervous tissue during cerebral irradiation, was not established.