Journal de cytologie et d'histologie

Comparison of Clinic-Pathological, Molecular Features and PD-L1 Status in a Series of Non-small Cell Lung Cancers: Are Real Life Data Similar to Clinical Trials results?

Abstract

Elshiekh M, Mani A, Kitson R, Josephides E, Clifford A, Rieu R, Desai S, Gupta N, Berry M, Bloch S, Ross C, Anderson J, Nandi J, Roddie M, Copley S, Denton A, Hatcher O, Power D, Lewanski C, Newsom-Davis T and Patrizia Viola

Objective: Immunotherapy is a promising treatment option for a subset of lung cancers as it utilizes the host’s own immune system to attack tumors cells. Selection of patients who are likely to respond to immunotherapy is based on PD-L1 expression, a specific biomarker. Clinic-pathological correlation of PD-L1 status and NSCLC has been explored in several studies and large clinical trials. However, there is discrepancy of data as several antibodies are available. We looked at a series of lung tumors to study the association between PD-L1 expression and patient characteristics in our daily setting to improve the selection of patients more likely to express this marker. Results were compared to those available in literature using the same antibody.
Methods: We analysed PD-L1 status (using Dako clone 22C3) in 170 non-small cell lung cancers and correlated their PD-L1 status with clinical, pathological and molecular characteristics focusing in particular on EGFR and ALK status.
Results: We found a statistically significant association between PD-L1 status, histological pattern in the
adenocarcinomas subtype and stage of the disease.
Conclusion: Our results support the current findings that PD-L1 expression more frequently occurs in advanced stage disease and certain histological pattern. Our data also confirmed longer survival in PD-L1 positive patients.
Highlights
• Immunotherapy is a promising option for the treatment of NSCLC
• PD-L1 status detected by immunohistochemistry is linked to immunotherapy response.
• There are many clones available but only 22C3 is approved as companion diagnostic
• Patient selection can be affected by the antibody used.