PD-L1 Testing and Assessment: Practical Considerations for Oncologist and Pathologist

Introduction

Recently, immunotherapy with anti-PD-1(programmed cell death protein 1) or anti-PD-L1 (programmed cell death ligand 1) antibodies has shown both favorable and durable responses in a subset of patients with metastatic and advanced cancers. Although no robust predictive biomarker for immune checkpoint inhibitors (ICI) has been established till date, PD-L1 immunohistochemistry (IHC) testing has emerged with a passable utility. However, PD-L1 is still far from being a perfect biomarker. Nevertheless, PD-L1 testing by IHC to evaluate the immunoexpression of PD-L1 protein in tumor cells and/or immune cells is a useful predictive biomarker for predicting response to ICI.[1] [2] [3] [4]

Source of Support

None declared.

Publikationsverlauf

Artikel online veröffentlicht:
28. November 2022

• References

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