Prognostic significance of CD3+ and CD8+ T-cells immunoscore in renal cell carcinoma: A comparison between two simple models for assessment

The immunoscore (ISc) has been extensively investigated as a prognostic indicator for numerous solid tumors. In renal cell carcinoma (RCC), its prognostic significance has been evaluated in a small number of studies. This study was designed to ascertain the prognostic value of ISc based on CD3+ and CD8+ T cells in patients with RCC. This study included 115 non-metastatic RCC patients who underwent nephrectomy. The ISc was obtained by estimating the densities of CD3+ and CD8+ cells at the invasive margin and center of the tumor using two methods: cell count per square millimeter (cell count/mm²) and percentage of cells per square millimeter (% of cells/mm²). The patients were categorized into low and high groups according to the ISc. The associations between the ISc and clinicopathological characters, including survival, were analyzed statistically. Adverse clinicopathologic factors were significantly associated with high ISc. Patients with high ISc had significantly worse overall survival (OS) and disease-free survival (DFS) rates over three years (p < 0.001). High ISc was considered a predictor of shortened DFS in univariate analysis (p < 0.001). However, in multivariate analysis, it was a dependent predictor. High ISc could help identify individuals more likely to develop recurrence and may impact treatment strategy for more effective personalized care. Moreover, establishing a modified objective, automated, digital quantification method of immune cells (% of cells/mm² instead of cell count/mm²) is expected to be simple to implement in routine, highly affordable, time efficient, clinically meaningful, and will improve assay performance.