An explorative analysis of the prognostic value of lactate dehydrogenase for survival and the chemotherapeutic response in patients with advanced triple-negative breast cancer

Serum lactate dehydrogenase (LDH) level is predictive of prognosis in various malignancies. Nevertheless, the association between the prognosis of patients with advanced triple-negative breast cancer (TNBC) and LDH is not well understood. This explorative and retrospective study was conducted to clarify the issue. We found that abnormal baseline LDH levels (> 250 IU/L) were significantly associated with age (> 40 y vs. ≤ 40 y, OR: 0.383, P = 0.031) and number of metastatic sites (2 vs. 1, OR: 4.619, P = 0.006; ≥ 3 vs. 1, OR: 4.727, P = 0.002). The progression-free survival (PFS) of patients with post-treatment LDH higher than baseline (Group 1) was significantly shorter than that in patients with LDH decreased to normal (Group 3) and those with normal baseline and post-treatment LDH (Group 4) (Group 3 vs. Group 1, HR: 0.517, P = 0.038; Group 4 vs. Group 1, HR: 0.346, P < 0.001). Overall survival (OS) in patients with abnormal baseline LDH was significantly shorter than in patients with normal baseline LDH (abnormal vs. normal, HR: 2.073, P < 0.001). Patients whose post-treatment LDH decreased to normal had the most objective response (complete and partial responses) rate after first-line chemotherapy (Group 3 vs. Group 1, OR: 0.074, P < 0.001). In this exploratory analysis, baseline LDH levels associated with OS, while LDH changes after first-line chemotherapy associated with PFS and the chemotherapeutic response. These results show that LDH may have important prognostic value for the survival and chemotherapeutic response in patients with advanced TNBC.