PD-L1 IHC 28-8 pharmDx is a qualitative immunohistochemical assay using monoclonal rabbit anti-PD-L1, clone 28-8 intended for use in the detection of PD-L1 protein in formalin-fixed, paraffin-embedded (FFPE) gastric carcinoma, gastroesophageal junction carcinoma (GEJ) and esophageal adenocarcinoma (EAC) tissues using EnVision FLEX visualization system on Autostainer Link 48. Although PD-L1 testing has not received the FDA-approval for these tumor types, the CHECKMATE 649 Study showed that OPDIVO® (nivolumab) in combination with chemotherapy demonstrated superior overall survival (OS) and progression-free survival (PFS) when compared to chemotherapy alone. Tissues with PD-L1 Combined Positive Score (CPS) 5 are considered to have PD-L1 expression. Stain-only (tech-only) testing is available to clients who have completed the test kit manufacturers online interpretation training. All PD-L1 IHC test options may be viewed here.
PD-L1 28-8 (OPDIVO®) for Gastric/GEJ/EAC
- Immunohistochemistry (IHC)
- Epic Aura Integration
Specimen Requirements
Preferred specimen (FFPE block):
A formalin-fixed, paraffin-embedded (FFPE) tissue block is the preferred specimen type. Use 10% NBF fixative; do not use zinc or mercury fixatives.
If submitting slides (instead of a block):
Submit the following. All slides cut at 4–5 microns. Please use positively-charged slides and 10% NBF fixative.
H&E slide: One (1) unbaked, unstained slide for H&E staining (required)
Cut Slides: Two (2) positively charged unstained slides for each IHC test/antibody ordered
Specimen identification:
Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.
A formalin-fixed, paraffin-embedded (FFPE) tissue block is the preferred specimen type. Use 10% NBF fixative; do not use zinc or mercury fixatives.
If submitting slides (instead of a block):
Submit the following. All slides cut at 4–5 microns. Please use positively-charged slides and 10% NBF fixative.
H&E slide: One (1) unbaked, unstained slide for H&E staining (required)
Cut Slides: Two (2) positively charged unstained slides for each IHC test/antibody ordered
Specimen identification:
Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.
Storage and Transportation
Slides may be stored at room temperature; transport with cold pack, making sure cold pack is not in direct contact with specimen.
NYS Clients: Please provide Date and Time of Collection.
CPT Code(s)*
88360x1
Turnaround time
1-2 Days
Global: 2 Days
Tech-Only (stain only): 24 Hours
Level of Service
- Global
- Tech Only
Integrations
- Epic Aura
New York Approved: Yes
*The CPT codes provided with our test descriptions are based on AMA guidelines and are for informational purposes only. Correct CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed.
Biomarkers
Immunohistochemistry (IHC)
| Expression | |||||
|---|---|---|---|---|---|
| PD-L1 | |||||
Last Updated: March 18, 2026