Platelet-to-lymphocyte ratio in peripheral blood: A novel independent prognostic factor in patients with melanoma.

Objectives: This retrospective study aimed to investigate the prognostic value of pre-treatment platelet-to-lymphocyte ratio (PLR), which is an inflammatory indicator, in patients with melanoma.

Methods: Patients in this retrospective analysis were admitted between January 1, 2010 and December 31, 2015 in Henan Cancer Hospital. Receiver operating characteristic (ROC) curve was performed the optimal cut-off value for PLR. The 140 patients were divided into two groups: high PLR group and low PLR group. The relationship between PLR and overall survival (OS) was analyzed. The Kaplan-Meier and Log rank tests were used for univariate survival analysis and Cox proportional hazards regression model for multivariate analysis.

Results: The optimal cut-off value of PLR determined by ROC curve was 120.15. Univariate and Cox multivariate survival analysis all showed that PLR and clinical stage were factors affecting OS in melanoma patients (P < 0.05). The overall median OS was 21.0 months (95% confidence interval (CI): 18.1-23.9), for 17.0 months in the high PLR group, and 34.0 months in the low PLR group (hazard ratio: 0.436, 95% CI: 0.291-0.652, P < 0.001), respectively. Clinical subgroup analysis showed that PLR was a risk factor in patients with stage II, III, and IV disease (P < 0.05).

Conclusion: The elevated PLR was an independent prognostic predictor for OS in patients with melanoma.