High ratio of programmed cell death protein 1 (PD-1)+/CD8+ tumor-infiltrating lymphocytes identifies a poor prognostic subset of extrahepatic bile duct cancer undergoing surgery plus adjuvant chemoradiotherapy. Issue 1 (October 2015)

• Record Type: Journal Article
• Authors: Lim, Yu Jin; Koh, Jaemoon; Kim, Kyubo; Chie, Eui Kyu; Kim, BoKyong; Lee, Kyoung Bun; Jang, Jin-Young; Kim, Sun-Whe; Oh, Do-Youn; Bang, Yung-Jue; Ha, Sung W.
• Is Part Of: Radiotherapy and oncology. Volume 117:Issue 1(2015:Oct.)
• Page Start: 165
• Page End: 170
• Publication Date: 2015-10
• Subjects: Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2015.07.003
• Languages: English
• ISSNs: 0167-8140

Abstract

<abstract xml:lang="en" abstract-type="author" id="ab005"> <title id="st005">Abstract</title> <sec> <title id="st010">Background and purpose</title> <p id="sp0005">This study investigated the prognostic role of PD-L1 expression, PD-1<sup>+</sup> tumor-infiltrating lymphocytes (TILs), and the ratio of PD-1<sup>+</sup>/CD8<sup>+</sup> TILs in extrahepatic bile duct (EHBD) cancer.</p> </sec> <sec> <title id="st015">Materials and methods</title> <p id="sp0010">We analyzed 83 patients with EHBD cancer who underwent curative surgery plus fluoropyrimidine-based chemoradiotherapy (CRT). Expressions of PD-L1, PD-1, and CD8 were assessed by immunohistochemistry.</p> </sec> <sec> <title id="st020">Results</title> <p id="sp0015">Fifty-six (68%) patients were PD-L1-positive, and its lower expression level was associated with hilar tumor location (<italic>P</italic> = 0.044). A higher ratio of PD-1<sup>+</sup>/CD8<sup>+</sup> TILs was associated with poorer overall survival (OS) (<italic>P</italic> = 0.032), relapse-free survival (RFS) (<italic>P</italic> = 0.024), and distant metastasis-free survival (DMFS) (<italic>P</italic> = 0.039) in Kaplan–Meier analyses, but survival differences were not observed according to the PD-L1 expression level. With Cox proportional hazards models, the ratio of PD-1<sup>+</sup>/CD8<sup>+</sup> TILs was the independent prognostic factor in OS (HR 2.47, 95% CI 1.04–5.86), RFS (HR 2.41, 95% CI 1.08–5.41), and DMFS (HR 2.67, 95% CI 1.00–7.11) after adjusting for other significant clinicopathologic variables.</p> </sec> <sec> <title id="st025">Conclusion</title> <p id="sp0020">A strong survival impact of the ratio of PD-1<sup>+</sup>/CD8<sup>+</sup> TILs was observed in EHBD cancer. In the poor prognostic subgroup, the blockade of the immune checkpoint in combination with conventional multimodality treatment needs to be considered.</p> </sec> </abstract>