Prognostic significance of platelet-to-lymphocyte ratio in non-small-cell lung cancer: a meta-analysis

Abstract

BackgroundThe platelet-to-lymphocyte ratio (PLR) is a useful predictive factor in several cancers. However, the prognostic value of PLR in patients with non-small-cell lung cancer (NSCLC) is still indistinct. Therefore, it was necessary for us to perform a meta-analysis to assess the prognostic value of PLR in patients with NSCLC.MethodsA systematic literature search was performed by using PubMed, EMBASE, and Web of Science databases for relevant studies until May 2015. Published studies investigating the association between PLR and overall survival (OS) and disease-free survival (DFS) were selected. Data from each eligible study were extracted. A meta-analysis was performed to analyze the prognostic value of PLR by using the hazard ratio (HR) and 95% confidence intervals (95% CI).ResultsA total of seven studies involving 1,554 patients were included in our meta-analysis. Our pooled results demonstrated that high PLR was associated with poor OS (HR: 1.60, 95% CI: 1.34–1.90, I2=22.3%, Pheterogeneity = 0.259) and DFS (HR: 1.38, 95% CI: 1.11–1.73, I 2=0%, Pheterogeneity = 0.482). Subgroup analysis between PLR and OS was performed in a further investigation. When the patients were segregated according to ethnicity, sample size, cutoff value, stage, and treatment modality, high PLR was also significantly correlated with OS. There was no significant heterogeneity among included studies.ConclusionHigh PLR is associated with poor prognosis in patients with NSCLC. PLR may be a significant predictive biomarker in patients with NSCLC.

Platelet count and platelet‐lymphocyte ratio as prognostic markers for head and neck squamous cell carcinoma: Meta‐analysis

“…62 These interactions between tumor cells and platelets contribute to poor prognosis in patients with cancer. 19,20,[23][24][25][26][27][28]30,32,33,63 Studies regarding HNSCC, most of which have been published over the past few years (Tables 1 34-40,51 and 2 37,38,[41][42][43][44][45][46]51 ), showed differing disease sites, stage of disease, treatment modalities, cutoff values, and primary end points. 15,16 An increasing number of studies are investigating the association between thrombocytosis and mortality in patients with cancer.…”

“…15,16 An increasing number of studies are investigating the association between thrombocytosis and mortality in patients with cancer. 19,20,[23][24][25][26][27][28]30,32,33,63 Studies regarding HNSCC, most of which have been published over the past few years (Tables 1 [34][35][36][37][38][39][40]51 and 2 37,38,[41][42][43][44][45][46]51 ), showed differing disease sites, stage of disease, treatment modalities, cutoff values, and primary end points. Thus, the reported impact of elevated platelet count and PLR differs significantly among studies.…”

“…Tissue specimens allow for the direct examination of tumor and stromal cells. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] Although the association between these markers and HNSCC prognosis has been investigated, the results have been inconsistent. However, blood samples can easily be obtained at any time, and blood markers can be measured repeatedly.…”

“…14 Platelet count and plateletlymphocyte ratio (PLR) are hematologic makers that have shown prognostic abilities across many types of cancers. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] Although the association between these markers and HNSCC prognosis has been investigated, the results have been inconsistent. [34][35][36][37][38][39][40][41][42][43][44][45][46] Among these studies, only 1 study was prospective.…”

The platelet-to-lymphocyte ratio as a predictor of patient outcomes in ovarian cancer: a meta-analysis

“…First, PLR can be measured in routine blood tests performed in daily clinical practice, making it easy to measure, low cost, and reproducible 31,32 . Second, the prognostic value of the PLR has been demonstrated in a wide variety of tumor types 33 .…”