Longitudinal analysis of PD-L1 expression in patients with relapsed NSCLC

• Published in: Journal for immunotherapy of cancer Vol. 12; no. 4; p. e008592
• Main Authors: John, Nikolaus, Schlintl, Verena, Sassmann, Teresa, Lindenmann, Jörg, Fediuk, Melanie, Wurm, Robert, Douschan, Philipp, Zacharias, Martin, Kalson, Lipika, Posch, Florian, Absenger, Gudrun, Brcic, Luka, Jost, Philipp J, Terbuch, Angelika
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 11.04.2024; BMJ Publishing Group LTD; BMJ Publishing Group
• Subjects: B7-H1 Antigen - metabolism; Biomarker; Biopsy; Carcinoma, Non-Small-Cell Lung - pathology; Clinical/translational cancer immunotherapy; FDA approval; Histology; Humans; Immune Checkpoint Inhibitor; Lung Cancer; Lung Neoplasms - pathology; Lymphatic system; Metastasis; Mutation; Neoplasm Recurrence, Local; Oncology; Patients; Recurrence; Retrospective Studies; Small Cell Lung Carcinoma; Surgery; Tumors; Immune Checkpoint Inhibitor; Biomarker; Lung Cancer
• DOI: 10.1136/jitc-2023-008592
• ISSN: 2051-1426

BackgroundThe use and approval of immune checkpoint inhibitors for the treatment of non-small cell lung cancer (NSCLC) depends on PD-L1 expression in the tumor tissue. Nevertheless, PD-L1 often fails to predict response to treatment. One possible explanation could be a change in PD-L1 expression during the course of the disease and the neglect of reassessment. The purpose of this study was a longitudinal analysis of PD-L1 expression in patients with relapsed NSCLC.MethodsWe retrospectively analyzed PD-L1 expression in patients with early-stage NSCLC and subsequent relapse in preoperative samples, matched surgical specimens and biopsy samples of disease recurrence. Ventana PD-L1 (SP263) immunohistochemistry assay was used for all samples. PD-L1 expression was scored based on clinically relevant groups (0%, 1%–49%, and ≥50%). The primary endpoint was the change in PD-L1 score group between preoperative samples, matched surgical specimens and relapsed tumor tissue.Results395 consecutive patients with stages I–III NSCLC and 136 (34%) patients with a subsequent relapse were identified. For 87 patients at least two specimens for comparison of PD-L1 expression between early stage and relapsed disease were available. In 72 cases, a longitudinal analysis between preoperative biopsy, the surgically resected specimen and biopsy of disease recurrence was feasible. When comparing preoperative and matched surgical specimens, a treatment-relevant conversion of PD-L1 expression group was found in 25 patients (34.7%). Neoadjuvant treatment showed no significant effect on PD-L1 alteration (p=0.39). In 32 (36.8%) out of 87 cases, a change in PD-L1 group was observed when biopsies of disease relapse were compared with early-stage disease. Adjuvant treatment was not significantly associated with a change in PD-L1 expression (p=0.53). 39 patients (54.2%) showed at least 1 change into a different PD-L1 score group during the course of disease. 14 patients (19.4%) changed the PD-L1 score group twice, 5 (6.9%) of them being found in all different score groups.ConclusionPD-L1 expression shows dynamic changes during the course of disease. There is an urgent need for consensus guidelines to define a PD-L1 testing strategy including time points of reassessment, the number of biopsies to be obtained and judgment of surgical specimens.