Serum lactate dehydrogenase levels at presentation predict outcome of patients with limited-stage small-cell lung cancer.

Serum lactate dehydrogenase (LDH) is a biochemical parameter that is elevated in the majority of extensive-stage small-cell lung cancer (SCLC). In this study, distribution and prognostic importance of serum LDH in limited-disease SCLC were investigated. Serum concentrations of LDH were measured in 184 patients at initial examination. These results were compared with prospectively recorded clinicopathologic characteristics and patient outcome data. Significant positive association was found between LDH levels and weight loss, performance status, response to chemotherapy, and albumin but not between age, gender, and hemoglobin values. Patients with high concentrations of LDH had a significantly worse prognosis than did patients with normal levels. The probability of overall survival at 1 year was 60.2% in patients with normal serum LDH levels and 33.1% in patients with higher values (p = 0.0017). Also, the prognostic value of LDH on overall survival was shown in multivariate analysis (p = 0.05). At the time of diagnosis, serum levels of LDH appear to have a significant relation to outcome in patients with limited-stage SCLC.