Significance of Serum Lactic Dehydrogenase in Stages B and C Non-Seminomatous Testis Tumors

Abstract

The incidence of initial elevations of total serum lactic dehydrogenase was 38% in 21 patients with stage B [nonseminomatous testis tumors] and 65% in 17 patients with stage C. Conversely, 62% of patients with stage B disease and 35% of patients with stage C disease had normal lactic dehydrogenase values, indicating that measurement of total serum lactic dehydrogenase lacks sensitivity as a useful biologic tumor marker in predicting the presence of tumor. There were no falsely positive elevations in these patients, all patients with persistent elevations after therapy have died or have progressive disease. Total serum lactic dehydrogenase apparently should be measured initially in all patients with advanced disease (stages B3 and C). When elevated, serial measurements will indicate response to therapy. The presence of a persistent elevation of lactic dehydrogenase suggests that current conventional therapeutic modalities are ineffective and alternative therapy should be instituted.