PD-L1 IHC
Pronunciation: P-D-L-one I-H-C
Also written as: IHC — immunohistochemistry
Programmed Death-Ligand 1 immunohistochemistry testing to assess immune checkpoint protein expression.
Full Definition
PD-L1 IHC (Programmed Death-Ligand 1 immunohistochemistry) is a diagnostic test that measures PD-L1 protein expression in tumor cells and immune cells using antibody-based tissue staining. PD-L1 expression serves as a predictive biomarker for immune checkpoint inhibitor therapy response across multiple cancer types. Different PD-L1 antibodies and scoring systems exist, including tumor proportion score (TPS), combined positive score (CPS), and immune cell scoring. Editors must understand that PD-L1 IHC results vary by antibody clone, scoring method, and cancer type, requiring careful attention to assay specifications in clinical reports.
Usage
Usage note: Use hyphens in PD-L1, capitalize IHC. Specify antibody clone and scoring method when available.
In Context
- "PD-L1 IHC using the 22C3 antibody showed 65% tumor proportion score in this lung adenocarcinoma." — immunotherapy biomarker report
- "The patient's high PD-L1 IHC expression (CPS ≥10) qualified them for first-line pembrolizumab therapy." — treatment planning document