TPS is calculated by dividing the number of tumour cells showing partial or complete PD-L1 membrane staining by the total number of all viable tumour cells present in the sample and multiplying the quotient by 100%.
CPS scoring – Definition of positive immune cells in contrast to positive tumour cells:
Positivity of immune cells:
Any membrane and/or cytoplasmic staining (at any intensity) of lymphocytes and macrophages (mononuclear inflammatory cells ; MICs) within tumour nests and/or adjacent supporting stroma is considered PD-L1 staining and should be included in scoring. Only MICs directly associated with the response against the tumour are scored.
Positivity of tumour cells:
Any convincing partial or complete linear membrane staining (at any intensity) of viable tumour cells that is perceived as distinct from cytoplasmic staining is considered PD-L1 staining and should be included in scoring.
Tumour cell
Tumour-associated immune cells
PD-L1–positive cell
Combined Positive Score (CPS)1
CPS =
of PD-L1 positive cells
Total # of viable tumour cells
x 100
CPS is reported as a numeric value.
CPS is calculated by dividing the number of PD-L1–positive tumour cells and tumour-associated immune cells
included:
lymphocytes
macrophages
excluded:
neutrophils
eosinophils
plasma cells
by the total number of all viable tumour cells in the sample and multiplying the quotient by 100. The maximum score is defined as CPS 100.
CPS scoring – Definition of tumour-associated immune cells:
Adjacent MICs are defined as being within the same 20x field as the tumour. However, MICs that are NOT directly associated with the response to the tumour should be excluded.
This is an example of an NSCLC specimen from the Agilent NSCLC manual for the PD-L1 IHC 22C3 pharmDx test, and is not meant to be representative of all patients and tissue stains. Furthermore, these images should not be used as a means to diagnose and prescribe KEYTRUDA®.
Please consult the KEYTRUDA® product monograph when determining whether PD-L1 testing is required for a particular KEYTRUDA® NSCLC indication.
This is an example of a TNBC specimen from the Agilent TNBC manual for the PD-L1 IHC 22C3 pharmDx test, and is not meant to be representative of all patients and tissue stains. Furthermore, these images should not be used as a means to diagnose and prescribe KEYTRUDA®.
Please consult the KEYTRUDA® product monograph when determining whether PD-L1 testing is required for a particular KEYTRUDA® TNBC indication.
