Prognostic Value Of The Systemic Immune-Inflammation Index (SII), Neutrophil-To-Lymphocyte Ratio (NLR), And Platelet-To Lymphocyte Ratio (PLR) In Patients With Oral Squamous Cell Carcinoma (OSCC) - A Systematic Revi

Abstract

BACKGROUND: Cancer represents a major global public health burden, affecting a significant proportion of the population worldwide. Among head and neck malignancies, oral squamous cell carcinoma (OSCC) is the most common histopathological subtype, accounting for nearly 90% of all oral cancers. The tumor microenvironment and systemic inflammatory response play significant roles in tumor progression, treatment response, and patient prognosis. OBJECTIVE: To evaluate, asses and combine all the current evidence on the prognostic significance of systemic inflammatory biomarkers, that are Systemic Immune-Inflammation Index (SII), Neutrophil-to-Lymphocyte Ratio (NLR), and Platelet-to-Lymphocyte Ratio (PLR) in Oral Squamous Cell Carcinoma. METHODS: Scientific publications published between 2015 and 2025 in multiple literature databases, such as the PubMed, Scopus, EBSCO, Google Scholar were searched. Preliminary research in well-known literature databases turned up to one thousand two hundred and ninety-six high-calibre academic works. Through application of stringent inclusion and exclusion criteria, we were able to reduce the number of articles from thousands to twelve RESULTS: The majority of the included studies demonstrated a significant association between elevated SII, NLR, and PLR values and adverse clinical outcomes, including reduced overall survival, disease-free survival, and progression-free survival. Prognostic value of all the three blood markers was observed. By far the most significant correlations being recorded was Systemic immune inflammation index CONCLUSION: The findings of this review suggest that SII, NLR, and PLR are promising, cost-effective, and readily available prognostic biomarkers in patients with OSCC. However, their prognostic utility may be enhanced when integrated with clinicopathological variables, nutritional indices, composite immune scores.