[Serum NSE (neuron-specific enolase) levels in small cell lung cancer, with special reference to the measurement of serial serum NSE levels].

Serum neuron-specific enolase (NSE) was measured in 105 patients with lung cancer without prior therapy. Increasing serum levels of NSE were observed in 84% of cases of small cell lung cancer (SCLC). 11% of adenocarcinomas, 18.5% of squamous cell carcinomas and 37.5% of large cell carcinomas. Serum NSE levels changed in parallel with the effect of initial treatment. Although two of 5 patients with SCLC, in whom serial NSE levels were measured after treatment, showed elevation of serum NSE levels before clinical relapse, elevated serum NSE levels were not observed in 3 patients at clinical relapse. These data seem to suggest that measurement of serial NSE is useful for predicting relapse prior to clinical recognition. However, it still remains an important point to carry out clinical general surveillance for relapse.