Inverse Association between Platelet-Lymphocyte Ratio and Prognosis in Terminally Ill Cancer Patients: A Preliminary Study

Background: An elevated platelet-lymphocyte ratio (PLR) is an indicator for worse outcomes in cancer, but its significance at the end of life remains unclear. Objective: This study aimed to investigate the value of PLR as an independent prognostic factor in terminally ill cancer patients. Methods: This retrospective cohort study included 312 terminal cancer patients and was conducted in a palliative care unit of a tertiary cancer center. Patient demographic data, clinical information, and laboratory values, including complete blood cell count, were obtained. Survival was analyzed using the Kaplan-Meier method and log-rank test. The Cox proportional hazards model was used to identify independent prognostic factors for survival. Results: Median survival was 16 days in patients with PLR >= 200 and 9 days in patients with PLR < 200 (p = 0.008). Results of multivariate analysis showed that the following factors predicted worse survival: poor performance status (adjusted hazard ratio [aHR], 2.16; 95% confidence interval [CI], 1.50-3.09), azotemia (aHR, 1.43; 95% CI, 1.01-2.02), hypoalbuminemia (aHR, 1.55; 95% CI, 1.07-2.26), hyperbilirubinemia (aHR, 1.67; 95% CI, 1.23-2.29), elevated lactate dehydrogenase (aHR, 1.58; 95% CI, 1.11-2.26), high neutrophillymphocyte ratio (aHR, 1.49; 95% CI, 1.09-2.04), and low PLR (aHR, 1.46; 95% CI, 1.08-1.97). Conclusion: Although elevated PLR indicates worse outcomes in patients with solid tumors, decreased PLR was an independent prognostic factor for poor survival in cancer patients at the end of life.