Differential expression of PD-L1 between sporadic and VHL-associated hereditary clear cell renal cell carcinoma and its correlation with clinicopathological features
Publication date: Available online 13 November 2018
Source: Clinical Genitourinary Cancer
Author(s): Baoan Hong, Lin Cai, Jiangyi Wang, Shengjie Liu, Jingcheng Zhou, Kaifang Ma, Jiufeng Zhang, Bowen Zhou, Xiang Peng, Ning Zhang, Kan Gong
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 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.
PD-L1 is a potential predictive biomarker for immunotherapy in several malignancies. However, the expression level and clinical significance of PD-L1 in VHL-associated hereditary ccRCC remain unclear.
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 by immunohistochemistry. Correlations between PD-L1 expression and clinicopathological features were analyzed.
In sporadic ccRCC, positive expression rate of PD-L1 was 47.3%. Positive PD-L1 expression was correlated with advanced tumor T stage (P = 0.011), higher Fuhrman nuclear grade (P = 0.022), poor disease-free survival (DFS) (P = 0.037) and gender (P = 0.025). In the VHL-associated hereditary ccRCC, positive PD-L1 expression rate was 34.6%, lower than that in sporadic ccRCC. Positive PD-L1 was correlated with higher Fuhrman nuclear grade (P = 0.008), but not with gender, age, tumor stage, or the onset age of VHL-associated tumors.
Positive PD-L1 expression was correlated with the aggressive clinicopathological features both in sporadic and VHL-associated hereditary ccRCC. Whether PD-L1 expression level in ccRCC is related to the effectiveness of PD-1/PD-L1 checkpoint inhibitor immunotherapy needs to be further investigated.