The prognostic effect of immunoscore in patients with clear cell renal cell carcinoma: preliminary results

This study aimed to evaluate the density of CD8⁺ and CD3⁺ tumor-infiltrating lymphocytes (TILs) and determine whether the immunoscore has any prognostic effect on the oncological outcomes in patients with clear cell renal cell carcinoma (RCC).

A total of 129 patients diagnosed with clear cell RCC following radical or partial nephrectomy between 2009 and 2014 were retrospectively analyzed. Both tumor core (CT) and the invasive margin of nephrectomy specimens were assessed. The specimens were immunostained for anti-CD8⁺ and anti-CD3⁺ TILs. The patients were divided into three groups (favorable, intermediate, and poor risk) according to immunoscore levels.

In the multivariate analysis, a favorable immunoscore (I3–4) was associated with prolonged disease-free survival (DFS), progression-free survival (PFS), and overall survival (OS) (HR 2.652, 2.848, and 2.933, respectively; all p < 0.001). The lower Fuhrman grade and pathological tumor-node-metastasis (TNM) stage had better DFS, PFS, and OS, whereas prolonged PFS was associated with a higher density of CD8⁺ CT (HR 1.602, 95% CI 0.934–3.470; p = 0.014). The shorter DFS, PFS, and OS were observed in the group with poor immunoscore (I0–1) at the early TNM stage of RCC (p < 0.001). In the metastatic subgroup analysis, the immunoscore showed better estimation than the International Metastatic RCC Database Consortium model and the Memorial Sloan-Kettering Cancer Center risk model for progression and OS (p < 0.001).

The additional contributions of immunoscore to TNM stage, Fuhrman grade, and the WHO/ISUP 2016 grade for estimating oncological outcomes were found in ROC analysis. According to our preliminary results, immunoscore can be a promising prediction tool in clear cell RCC for postoperative oncological outcomes following nephrectomy.