PD-L1 22C3 FDA (KEYTRUDA®) for TNBC (Breast)

  • Immunohistochemistry (IHC)

PD-L1 IHC 22C3 pharmDx is a qualitative immunohistochemical assay using Monoclonal Mouse Anti-PD-L1, Clone 22C3 intended for use in the detection of PD-L1 protein in formalin-fixed, paraffin-embedded (FFPE) triple-negative breast cancer (TNBC) tissue using EnVision FLEX visualization system on Autostainer Link 48. This test is indicated as an aid in identifying TNBC patients for treatment with KEYTRUDA® (pembrolizumab). Tissues with PD-L1 Combined Positive Score (CPS) ≥10 are considered positive. 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.

Turnaround time
Global: 2 Day, Tech-Only (stain only): 1 Day

Level of Service

  • Global
  • Technical Only
New York Approved: Yes

Specimen Requirements

Paraffin Block: 1 Block sent with a cold pack. No zinc or mercury fixatives. H&E: 1 unstained slide cut at 4-5 microns required. Cut Slides: 2 to 3 unstained slides cut at 4-5 microns. 1 slide per antibody/probe ordered. >100 viable tumor cells per probe set. Positively charged slides in 10% NBF. No zinc or mercury fixatives.

Storage and Transportation

Storage & Transportation: Use cold pack for transport, making sure cold pack is not in direct contact with specimen. NYS clients please provide date and time of Collection.

CPT Code(s)*

88360x1

*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.

Last Updated: January 16, 2025

Get in touch

Our Client Services team is on hand to help. Please call us at 866.776.5907, Option 3.