RT Journal Article
SR Electronic
T1 PD-L1 expression is an unfavourable prognostic indicator in Asian renal cell carcinomas
JF Journal of Clinical Pathology
JO J Clin Pathol
FD BMJ Publishing Group Ltd and Association of Clinical Pathologists
SP 463
OP 469
DO 10.1136/jclinpath-2019-206092
VO 73
IS 8
A1 Joe Yeong
A1 Zitong Zhao
A1 Jeffrey Chun Tatt Lim
A1 Huihua Li
A1 Aye Aye Thike
A1 Valerie Cui Yun Koh
A1 Bin Tean Teh
A1 Ravindran Kanesvaran
A1 Chee Keong Toh
A1 Puay Hoon Tan
A1 Li Yan Khor
YR 2020
UL http://jcp.bmj.com/content/73/8/463.abstract
AB 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.