Differential Expression of PD-L1 Between Sporadic and VHL-Associated Hereditary Clear-Cell Renal Cell Carcinoma and Its Correlation With Clinicopathological Features

Programmed death ligand-1 (PD-L1) inhibitor is an effective immunotherapy in the treatment of solid tumors. The expression of PD-L1 was evaluated in sporadic and von Hippel Lindau (VHL)-associated hereditary clear-cell renal cell carcinoma (ccRCC). Positive PD-L1 expression is associated with aggressive clinicopathological features not only in sporadic ccRCC but also in VHL-associated hereditary ccRCC. It provides a valuable consultation for clinical treatment. Background: Programmed death ligand-1 (PD-L1) is a potential predictive biomarker for immunotherapy in several malignancies. However, the expression level and clinical significance of PD-L1 in von Hippel-Lindau (VHL)-associated hereditary clear-cell renal cell carcinoma (ccRCC) remain unclear. Patients and Methods: Surgical specimens were recruited from 129 patients with sporadic ccRCC and 26 patients with VHL-associated hereditary ccRCC. The PD-L1 expression level was assessed using immunohistochemistry. Correlations between PD-L1 expression and clinicopathological features were analyzed. Results: In sporadic ccRCC, the positive expression rate of PD-L1 was 47.3% (61/129). Positive PD-L1 expression was correlated with advanced tumor T stage (P = .011), higher Fuhrman nuclear grade (P = .022), poor disease-free survival (P = .037), and sex (P = .025). In the VHL-associated hereditary ccRCC, positive PD-L1 expression rate was 34.6% (9/26), lower than that in sporadic ccRCC. Positive PD-L1 was correlated with higher Fuhrman nuclear grade (P = .008), but not with sex, age, tumor stage, or the onset age of VHL-associated tumors. Conclusion: Positive PD-L1 expression was correlated with the aggressive clinicopathological features in sporadic and VHL-associated hereditary ccRCC. Whether PD-L1 expression level in ccRCC is related to the effectiveness of programmed death-1/PD-L1 checkpoint inhibitor immunotherapy needs to be further investigated. (C) 2018 Elsevier Inc. All rights reserved.