TY - JOUR T1 - PD-L1 expression is an unfavourable prognostic indicator in Asian renal cell carcinomas JF - Journal of Clinical Pathology JO - J Clin Pathol SP - 463 LP - 469 DO - 10.1136/jclinpath-2019-206092 VL - 73 IS - 8 AU - Joe Yeong AU - Zitong Zhao AU - Jeffrey Chun Tatt Lim AU - Huihua Li AU - Aye Aye Thike AU - Valerie Cui Yun Koh AU - Bin Tean Teh AU - Ravindran Kanesvaran AU - Chee Keong Toh AU - Puay Hoon Tan AU - Li Yan Khor Y1 - 2020/08/01 UR - http://jcp.bmj.com/content/73/8/463.abstract N2 - Background/aims The programmed cell death receptor 1 (PD-1) checkpoint inhibitor, nivolumab, has been approved for the treatment of metastatic renal cell carcinoma (RCC). However, the understanding of the expression and distribution of PD ligand 1 (PD-L1) in the tumour immune microenvironment and its prognostic role in an Asian cohort is limited. Our group investigated PD-L1 protein expression in a cohort of Asian patients with RCC of mixed ethnicity, using two commercially available antibody clones.Methods E1L3N and SP263 anti-PD-L1 clones were used to categorise RCCs of various histological subtypes, diagnosed at our institution between 1995 and 2008, into PD-L1-positive or PD-L1-negative groups, based on a 1% Tumour Proportion Score (TPS) cut-off.Results In total, 267 (83%) clear cell (cc)RCC and 55 (17%) non-ccRCC cases were studied. Overall PD-L1 protein expression rates for the entire cohort were 13% and 8% for the E1L3N and SP263 clones, respectively. Patients bearing PD-L1-positive tumours experienced significantly decreased disease-free survival (DFS; E1L3N: p=0.01; SP263: p=0.03) but not overall survival, compared with those with PD-L1-negative tumours. Multivariate survival analysis further confirmed the results of the E1L3N clone (HR 1.85, 95% CI 1.10 to 3.13, p=0.02), but not SP263, after adjusting for pathological stage, histological subtype and grade. The addition of PD-L1 (E1L3N) TPS to clinicopathological features significantly increased the prognostic value for DFS (∆LRχ2=5.25; p=0.022), compared with clinicopathological features alone.Conclusions PD-L1 protein expression was associated with an unfavourable prognosis in our study cohort. PD-L1 (E1L3N) expression was an independent prognostic indicator of clinical outcome in all RCCs when using a 1% cut-off. ER -