Insight Into the Significance of CD8+ Tumor‐Infiltrating Lymphocytes in Lung Adenocarcinoma

ABSTRACT Background Despite great expectations regarding the use of tumor‐infiltrating lymphocytes (TILs) in predicting the effects of immunotherapies and prognosis, knowledge about TILs remains inadequate for clinical application. We re‐evaluated the clinicopathological significance of CD8+ tumor‐i...

Full description

Saved in:
Bibliographic Details
Main Authors: Kazu Shiomi, Masaaki Ichinoe, Ai Ushiwata, Ryo Nagashio, Shoko Hayashi, Dai Sonoda, Yasuto Kondo, Satoru Tamagawa, Shunsuke Mitsuhashi, Yuka Sugiyama, Masahito Naito, Masashi Mikubo, Masayuki Shirasawa, Yoshiro Nakahara, Takashi Sato, Katsuhiko Naoki, Yoshiki Murakumo, Koji Eshima
Format: Article
Language:English
Published: Wiley 2025-07-01
Series:Thoracic Cancer
Subjects:
Online Access:https://doi.org/10.1111/1759-7714.70135
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:ABSTRACT Background Despite great expectations regarding the use of tumor‐infiltrating lymphocytes (TILs) in predicting the effects of immunotherapies and prognosis, knowledge about TILs remains inadequate for clinical application. We re‐evaluated the clinicopathological significance of CD8+ tumor‐infiltrating lymphocytes (CD8 + TILs) in lung adenocarcinoma from a novel perspective and through a more objective approach using cell counting software. Methods Among patients with surgical resection of lung adenocarcinoma in 2011–2017, 156 patients with pathological stage IB–III were immunohistochemically studied to evaluate CD8 + TILs in the tumor stroma. The impact of CD8 + TILs on relapse‐free survival was analyzed by Kaplan–Meier survival and multivariate Cox proportional hazards analyses. Results Our analysis showed that patients with large numbers of CD8 + TILs in the stroma are not a homogeneous population and include subpopulations with a poor prognosis. Furthermore, our study showed important findings about the overall inflammatory status in the tumor microenvironment based on the association between the number of CD8 + TILs and the frequency of vascular invasion. Additionally, CD8 + TILs were shown to potentially be more effective than PD‐L1. Conclusions Our study demonstrated that in lung adenocarcinoma, even among populations with abundant CD8 + TILs in the tumor stroma, there may be a poor prognostic subgroup. Furthermore, we revealed a partial yet important relationship between CD8 + TILs and the tumor microenvironment. A more detailed investigation into the significance of CD8 + TILs may lead to a deeper understanding of the inflammatory status of the tumor microenvironment and ultimately contribute to the identification of appropriate biomarkers for prognostic prediction and assessing the efficacy of immune checkpoint inhibitors.
ISSN:1759-7706
1759-7714