High serum lactate dehydrogenase predicts an unfavorable outcome in Chinese elderly patients with multiple myeloma

There is significant heterogeneity among multiple myeloma (MM) patients with the survival duration varying greatly from a few months to several years. This study retrospectively analyzed serum lactate dehydrogenase (LDH) in 105 cases of newly diagnosed elderly MM patients to investigate its value for outcome prediction. Serum LDH concentrations were evaluated prior to induction therapy. Prognostic analyses were carried out based on LDH levels and patients' other clinical data. We also applied the recently proposed Revised International Staging System (R-ISS) to 70 patients with the available data. Of all the patients, elevated serum LDH levels (≥271U/L) were observed in 13.3% (14 out of 105) patients at diagnosis. Compared with normal LDH group, high LDH group had significantly shorter overall survival (OS) (15.5 vs. 52.5 months, p = 0.002) and median progression free survival (PFS) (12.0 vs. 24 months, p = 0.030), as well as 2-year OS rate (20% vs. 81%, p < 0.001) and PFS rate (22% vs. 44%, p = 0.005). A multivariate analysis identified high LDH as a unique independent adverse prognostic parameter for both OS and PFS. In addition, there were significant differences between R-ISS II and R-ISS III patients in both median OS (52.5 vs. 15.5 months, p < 0.001) and PFS (23 vs. 7.5 months, p = 0.004). Furthermore, high LDH was a unique independent adverse indicator for overall response rate (ORR) and early death in elderly MM patients. These results identified LDH as an unfavorable prediction for the outcome of Chinese elderly patients with MM. R-ISS based on LDH is superior to ISS in prognostic assessment.