83055-4

LOINC code 83055-4 identifies "PD-L1 by clone 28-8 [Presence] in Tissue by Immune stain". This term should be used to report the presence of PD-L1 (CD274) protein expression in tumor cells as determined by immune staining with anti-PD-L1 clone 28-8. Patients with certain cancers, such as non-squamous non small cell lung cancer (NSCLC) or melanoma, whose tumors are positive for PD-L1 by 28-8 may be eligible for anti-programmed death 1 (PD-1) receptor antibody therapy, which effectively prevents the binding of PD-L1 to PD-1. The percentage of viable tumor cells that show partial or complete PD-L1 membrane staining is reported using [83053-9]. A tumor with >= 1% staining by 28-8 is considered PD-L1 positive. This term was created for, but is not limited in use to, the Dako PD-L1 28-8 pharmDx test kit, which, as of November 2016, is FDA-approved as a companion diagnostic to assess whether patients with certain cancers are eligible for nivolumab therapy.

This code measures Programmed cell death ligand 1 by clone 28-8 in Tiss. It belongs to the PATH class in the LOINC classification.

LOINC (Logical Observation Identifiers Names and Codes) is a universal standard for identifying laboratory and clinical observations. It is maintained by the Regenstrief Institute and used worldwide for health data exchange.