Neuron-specific enolase (NSE) in serum. Comparison of monoclonal versus polyclonal assay based on 392 blood samples.

Neuron-specific enolase (NSE) is the best described serum tumor marker for small cell lung cancer (SCLC). Almost all clinical studies carried out so far used assays involving polyclonal antibodies against NSE; the majority of the studies analyzed the samples by a RIA NSE kit. We evaluated a new monoclonal kit and compared it to the polyclonal kit. We analyzed 392 serum samples, 265 from patients with SCLC, 88 from non-small cell lung cancers (NSCLC) and 39 from children with neuroblastomas. We found a good correlation between the results of the two assays. When correlating NSE in SCLC as measured with the two assays with clinical data, we found the same sensitivity, prognostic impact and value in treatment monitoring. We conclude that the "new" monoclonal assay is a fully acceptable alternative to the "old" polyclonal assay.