Abstract
Richard Kim1, Domenico Coppola2, Emilie Wang3, Young Doo Chang4, Yuhree Kim5, Daniel Anaya1 and Dae Won Kim1
1Department of Gastrointestinal Oncology, Moffitt Cancer Center, Tampa, FL, USA
2Department of Anatomic Pathology, Moffitt Cancer Center, Tampa, FL, USA
3Department of Internal Medicine, University of South Florida, Tampa, FL, USA
4Department of Supportive Care, Moffitt Cancer Center, Tampa, FL, USA
5Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Correspondence to:
Richard Kim, email: richard.kim@moffitt.org
Keywords: cholangiocarcinoma; tumor infiltrating lymphocytes; tumor microenvironment; PD-L1
Received: December 27, 2017 Accepted: April 02, 2018 Published: May 04, 2018
ABSTRACT
Cholangiocarcinoma is a malignancy arising from the biliary tract epithelial cells with poor prognosis. Tumor infiltrating lymphocytes (TIL)s and programmed cell death receptor ligand 1 (PD-L1) have a prognostic impact in various solid tumors. We aimed to investigate TILs and PD-L1 expression and their clinical relevance in cholangiocarcinoma. Tumor samples from 44 patients with resected and histologically verified extrahepatic cholangiocarcinoma were evaluated for CD8, CD45RO and PD-L1 expression, and their correlations with clinicopathological data and survival data were analyzed. Total 44 extrahepatic cholangiocarcinoma tissues were evaluated. CD8+ tumor infiltrating lymphocytes (TIL)s were observed in 30 (68%) tumors. Among them, 14 had CD8+CD45RO+ TILs. PD-L1 was expressed on cancer cells in 10 (22.7%) tumors in 34 evaluable extrahepatic cholangiocarciniomas. The presence of CD8+ TILs or CD8+CD45RO+ TILs was not associated with clinical staging or tumor differentiation. Extrahepatic cholangiocarcinoma with CD8+CD45RO+ TILs had longer overall survival (OS) on univariate (P = 0.013) and multivariate (P = 0.012) analysis. Neither CD8+TIL nor PD-L1 expression on cancer cells correlated significantly with OS. These results add to the understanding of the clinical features associated with CD8 TILs and PD-L1 expression in extrahepatic cholangiocarcinoma, and they support the potential rationale of using PD-1 blockade immunotherapy in cholangiocarcinoma.