platelet - lymphocyte ratio (PLR)

Last edited 03/2022 and last reviewed 05/2022

Platelet-Lymphocyte ratio (PLR)

PLR is defined as the ratio of platelets to lymphocytes

• studies show that platelets and lymphocytes play multiple roles in the inflammatory response
  • platelet elevation accelerates tumor progression by promoting the formation of new blood vessels and the production of adhesion molecule (1)
    
    
• lymphocytes are an important component of anti-tumor immunity, releasing a range of cytokines that activate anti-tumor immunity (2)
  
  
• the prognosis of multiple solid tumors is related to a series of inflammatory factors such as PLR have been confirmed (3,4)
  
  
• elevated PLR is closely related to poor prognosis in a variety of cancer patients (3)
  
  
• elevated pre-treatment PLR was a prognostic factor for poor overall survival and disease free survival and associated with poor clinicopathological parameters in gastric cancer patients (5)

Reference:

• Menter DG et al. Platelet "first responders" in wound response, cancer, and metastasis Cancer Metastasis Rev. 2017; 36 (2): 199-213
• Stanton SE, Disis ML. Clinical significance of tumor-infiltrating lymphocytes in breast cancer J. ImmunoTher. Cancer 2016; 4: 59
• Takenaka Y et al. Uno Platelet count and platelet-lymphocyte ratio as prognostic markers for head and neck squamous cell carcinoma: meta-analysis Head Neck 2018; 40 (12): 2714-2723
• Oh D et al. Prognostic roles of inflammatory markers in pancreatic cancer: comparison between the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio Gastroenterol. Res. Pract 2018:. 9745601
• Zhang X, Zhao W, Yu Y, et al. Clinicopathological and prognostic significance of platelet-lymphocyte ratio (PLR) in gastric cancer: an updated meta-analysis. World J Surg Oncol. 2020;18(1):191. Published 2020 Jul 30. doi:10.1186/s12957-020-01952-2