High serum lactate dehydrogenase adds prognostic value to the international myeloma staging system even in the era of novel agents.

OBJECTIVES: High serum lactate dehydrogenase (LDH) is associated with features of advanced disease and inferior survival in multiple myeloma. It is however unclear whether LDH adds to the prognostic value of International Staging System (ISS) and whether it retains its prognostic significance in patients who are exposed to novel agent-based therapies. PATIENTS/METHODS: To address these issues we analyzed 996 consecutive symptomatic patients who were included in the database of the Greek Myeloma Study Group and received frontline treatment between January 1, 1995 and December 31, 2008. RESULTS: The median overall survival (OS) of all patients was 40 months with a clear improvement in those who started treatment after January 1, 2000 (49 vs. 31 months; P < 0.01). A multivariate model showed that LDH, ISS, performance status, age and platelet counts had an independent prognostic value for OS (P < 0.001 for all parameters). The median OS of patients with high (11% of patients) and normal LDH was 15 vs. 44 months (P < 0.001). High LDH was associated with inferior OS within all ISS groups: 22 vs. 76 months for high and normal LDH groups, respectively, in ISS-1 (P < 0.01); 11 vs. 40 months in ISS-2 (P < 0.001) and 17 vs. 27 months in ISS-3 (P < 0.01). The median OS of high and normal LDH groups among patients who received novel agents was 21 vs. 51 months, respectively (P < 0.001). CONCLUSIONS: Lactate dehydrogenase is a readily available and inexpensive variable, which has a major impact on the survival of myeloma patients even when they belong to a low or intermediate ISS subgroup and even when they receive novel agent-based therapies.