Prognostic Value of Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio, and Lactate Dehydrogenase Level in Melanoma Patients Treated with Immune Checkpoint Inhibitors.

INTRODUCTION

Metastatic melanoma carries a poor prognosis. Immune checkpoint inhibitors (ICIs) have improved outcomes, but responses remain variable, highlighting the need for simple prognostic biomarkers. Inflammatory markers such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lactate dehydrogenase (LDH) reflect tumour burden and inflammation, though their clinical utility is unstandardised.

METHODS

We retrospectively analysed 103 metastatic melanoma patients treated with anti-PD-1 monotherapy at two centres in Western Australia (2014-2020). Baseline NLR, PLR, and LDH were assessed within 30 days pre-treatment. Outcomes included clinical benefit, progression-free survival (PFS), and overall survival (OS).

RESULTS

Poor ECOG performance status (PS ≥2) (RR 2.39, 95% CI 1.48-3.86) and elevated LDH (≥250 U/L) (RR 1.68, 95% CI 1.21-2.31) were associated with no clinical benefit ( < 0.001). NLR ≥5 predicted significantly worse OS (9.1 vs 28.2 months; HR 8.54, 95% CI 2.58-28.32;  < 0.001). Elevated LDH predicted shorter OS (6.0 vs 50.3 months; HR 3.68, 95% CI 1.65-8.21;  = 0.002) and PFS (19.0 months vs not reached; HR 2.51, 95% CI 1.37-4.72;  = 0.004).

CONCLUSION

ECOG PS ≥2 and elevated NLR were associated with no clinical benefit, while elevated NLR and LDH independently predicted poorer survival. These markers may serve as practical prognostic tools in metastatic melanoma treated with ICIs.