Prognostic and clinicopathological significance of the platelet-to-lymphocyte ratio in melanoma: A meta-analysis involving 2099 patients

To investigate the prognostic role of the platelet-to-lymphocyte ratio (PLR) in melanoma through a meta-analytical method. The literature was searched using the PubMed, Embase, Web of Science, Cochrane Library, and Scopus electronic platforms. Hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) and their corresponding 95% confidence intervals (CIs) were calculated. Begg's test and Egger's test were used to assess potential publication bias. A total of eight retrospective cohort studies involving 2099 patients were included in the meta-analysis. No significant association between the PLR and OS was found (HR = 1.39; 95% CI = 0.97-1.99;P= .075). There was also a nonsignificant correlation between the PLR and PFS (HR = 1.49; 95% CI = 0.98-2.27;P= .065). In addition, there was no significant association between the PLR and sex (odds ratio [OR] = 1.14; 95% CI = 0.23-5.66;P= .869) or age (OR = 0.81; 95% CI = 0.41-1.59;P= .539). No significant publication bias was found in this meta-analysis. The pooled analysis suggests that the PLR may not be a significant prognostic marker in patients with melanoma.