Neutrophil Lymphocyte Ratio, Platelet Lymphocyte Ratio, Systemic Inflammatory Response Index, and Systemic Immune-Inflammatory Index as Predictors of Metastasis in Renal Cell Carcinoma: A Retrospective Study

Background: The overall survival rates are below 10% in patients with metastatic renal cell carcinoma (RCC) posing a significant health challenge. There is a pressing need for novel and simple predictors of metastasis in patients with RCC to aid in early detection, thereby having prognostic and therapeutic implications. Objectives: To assess the efficacy of various inflammatory markers such as neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), Systemic Inflammatory Response Index (SIRI), and Systemic Immune-Inflammatory Index (SII), in predicting metastasis amongst individuals diagnosed with RCC. Methods: A retrospective study was undertaken at a tertiary hospital, focusing on individuals diagnosed with RCC. Patients were divided into two groups: Those with and without metastases. Patient demographics and clinical, pathological, and laboratory data were collected. The researchers evaluated the predictive capabilities of NLR, PLR, SIRI, and SII using ROC curves, with cut-off points determined via the Youden Index. Results: Of the 91 patients, 25 (27.5%) had metastatic RCC. Significant differences in NLR (P = 0.047), PLR (P = 0.004), SIRI (P = 0.006), and SII (P = 0.005) were noted between metastatic and non-metastatic groups. The ROC analysis showed that SIRI and SII had the highest predictive capacity with areas under the curve (AUCs) of 0.687 and 0.693, respectively. Logistic regression demonstrated NLR, PLR, SII, and SIRI as independent predictors of metastasis in RCC, with a combined predictive accuracy of 83.5%. Conclusions: Neutrophil-lymphocyte ratio, PLR, SIRI, and SII are reliable predictors of metastasis in RCC, with their combined use enhancing predictive accuracy. These hematological parameters can be easily derived from routine blood tests, could help in the early diagnosis of metastases, and tailor the management of RCC, improving patient outcomes. Further multicentric studies are recommended to validate these findings and help integrate them into clinical practice.