Department of Pulmonology, Huashan Hospital, Fudan University, Shanghai, China
Haihua Yang , Longgang Cui , Yuzi Zhang , Zhengyi Zhao , Yuezong Bai , Wenzhuan Xie
Background: Little is known about the pan-cancer PD-L1 expression landscape in Chinese patients although PD-L1 expression has been approved by FDA as a diagnosis for anti-PD-(L)1 therapy in several types of cancer. We did a cross-sectional analysis to assess the PD-L1 expression landscape in Chinese patients and its relationship with Tumor mutation burden (TMB). Methods: Tissue samples were collected from more than 8,000 consecutive cases in China between January, 2017, and August, 2019 and were analyzed by 3D Medicines, a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory. The method for NGS sequencing and tumor mutational burden (TMB) measurement were described previously. Clinical data and PD-L1 expression profiles were obtained from 8,063 patients whose tissue samples assed quality control. IHC staining for PD-L1 expression was performed using PD-L1 IHC 22C3 pharmDx assay (Dako North America, Carpentaria, CA, U.S.) or Ventana PD-L1 SP263 assay (Ventana Medical Systems, Tucson, AZ, U.S.). PD-L1 expression was determined using Tumor Proportion Score (TPS), the percentage of viable tumor cells stained. Results: PD-L1 expression was examined for 8,063 tissue samples collected from more than 18 different types of solid tumors. There were 4,866 (60%) male and 3,197 (40%) female patients. Their median age was 59 (IQR range, 50-66) years. Given the significance of different cut-points of PD-L1 expression in predicting clinical outcomes, expression levels of PD-L1 were arranged into the following intervals: < 1%, 1%-5%, 5%-50% and ≥50% for each cancer type. Small cell lung cancer (SCLC) had the lowest and Squamous Carcinoma of Head and Neck (HNSC) had the highest levels of PD-L1 expression. Spearman correlation analysis indicated no correlation between PD-L1 and tumor mutational burden (TMB) for Chinese cancer patients (R = 0.1, P < 0.01), which is in line with the previous reports that PD-L1 and TMB were two independent predictors in immunotherapy. Conclusions: The landscape of PD-L1 expression among Chinese cancer population in this study will further assist the utilization of PD-L1 as a predictive biomarker in clinical practice.
Disclaimer
This material on this page is ©2024 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org
Abstract Disclosures
2021 ASCO Annual Meeting
First Author: Stephanie Leigh Alden
2021 ASCO Annual Meeting
First Author: Richard S.P. Huang
2022 ASCO Annual Meeting
First Author: Seokhwi Kim
2023 ASCO Annual Meeting
First Author: Huangbin Lu