Programmed Death-Ligand 1 Expression in Lung Cancer and Paired Brain Metastases—a Single-Center Study in 190 Patients

Alexandra Kündig, MMed; Philipp Zens, MD; Christian Fung, MD; Amina Scherz, MD; Ferdinando Cerciello, MD, PhD; Evelyn Herrmann, MD; Ekin Ermis, MD; Ralph A. Schmid, MD; Erik Vassella, PhD; Sabina Berezowska, MD

JTO Clinical and Research Reports (Nov 2022)

Programmed Death-Ligand 1 Expression in Lung Cancer and Paired Brain Metastases—a Single-Center Study in 190 Patients

Alexandra Kündig, MMed,
Philipp Zens, MD,
Christian Fung, MD,
Amina Scherz, MD,
Ferdinando Cerciello, MD, PhD,
Evelyn Herrmann, MD,
Ekin Ermis, MD,
Ralph A. Schmid, MD,
Erik Vassella, PhD,
Sabina Berezowska, MD

Affiliations

Alexandra Kündig, MMed: Institute of Pathology, University of Bern, Bern, Switzerland
Philipp Zens, MD: Institute of Pathology, University of Bern, Bern, Switzerland; Graduate School for Health Sciences, University of Bern, Bern, Switzerland
Christian Fung, MD: Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; Present Address: Department of Neurosurgery, Medical Center, University of Freiburg, Freiburg, Germany
Amina Scherz, MD: Department of Medical Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Ferdinando Cerciello, MD, PhD: Department of Medical Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Evelyn Herrmann, MD: Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Ekin Ermis, MD: Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Ralph A. Schmid, MD: Division of General Thoracic Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
Erik Vassella, PhD: Institute of Pathology, University of Bern, Bern, Switzerland
Sabina Berezowska, MD: Institute of Pathology, University of Bern, Bern, Switzerland; Department of Laboratory Medicine and Pathology, Institute of Pathology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Corresponding author. Address for correspondence: Sabina Berezowska, MD, Department of Laboratory Medicine and Pathology, Institute of Pathology, Lausanne University Hospital and University of Lausanne, Rue du Bugnon 25, 1011 Lausanne, Switzerland.

Journal volume & issue: Vol. 3, no. 11
p. 100413

Abstract

Read online

Introduction: Expression of programmed death-ligand 1 (PD-L1) is the only routinely used tissue biomarker for predicting response to programmed cell death protein 1/PD-L1 inhibitors. It is to date unclear whether PD-L1 expression is preserved in brain metastases (BMs). Methods: In this single-center, retrospective study, we evaluated PD-L1 expression using the SP263 assay in consecutively resected BMs of lung carcinomas and paired primary tumors, diagnosed from 2000 to 2015, with correlation to clinicopathological and molecular tumor and patient characteristics. Results: PD-L1 tumor proportional score (TPS) could be evaluated on whole tissue slides in 191 BMs and 84 paired primary lung carcinomas. PD-L1 TPS was less than 1% in 113 of 191 (59.2%), 1% to 49% in 34 of 191 (17.8%), and greater than or equal to 50% in 44 of 191 (23.0%) BMs. TPS was concordant between BMs and paired primary lung carcinomas in most cases, with discordance regarding the clinically relevant cutoffs at 1% and 50% in 18 of 84 patients (21.4%). Four of 18 discordant cases had no shared mutations between the primary lung carcinoma and BM. Intratumoral heterogeneity, as assessed using tissue microarray cores, was only significant at the primary site (pWilcoxon signed rank = 0.002) with higher PD-L1 TPS at the infiltration front (mean = 40.4%, interquartile range: 0%–90%). Neither TPS greater than or equal to 1% nor TPS greater than or equal to 50% nor discordance between the primary lung carcinoma and BMs had prognostic significance regarding overall survival or BM-specific overall survival. Conclusions: PD-L1 expression was mostly concordant between primary lung carcinoma and its BM and between resections of BM and stereotactic biopsies, mirrored by tissue microarray cores. Differences in PD-L1 TPS existed primarily in cases with TPS greater than 10%, for which also human assessment tends to be most error prone.

Published in JTO Clinical and Research Reports

ISSN: 2666-3643 (Online)
Publisher: Elsevier
Country of publisher: United States
LCC subjects: Medicine: Internal medicine: Neoplasms. Tumors. Oncology. Including cancer and carcinogens
Website: https://www.journals.elsevier.com/jto-clinical-and-research-reports/

About the journal

Abstract

Keywords