Test Catalog

Test Id : 288PD

Programmed Death-Ligand 1 (PD-L1) (28-8), Semi-Quantitative Immunohistochemistry, Manual

Useful For
Suggests clinical disorders or settings where the test may be helpful

Identification of neoplasms expressing programmed cell death 1-ligand 1

Method Name
A short description of the method used to perform the test

Immunohistochemistry (IHC)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

PD-L1 (28-8), SemiQuant IHC, Manual

Lists additional common names for a test, as an aid in searching





Specimen Type
Describes the specimen type validated for testing


Ordering Guidance

Shipping Instructions

Attach the green pathology address label included in the kit to the outside of the transport container.

Necessary Information

A pathology/diagnostic report and a brief history, including primary site of neoplasm, are required.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Specimen Type: Tissue

Supplies: Pathology Packaging Kit (T554)

Collection Instructions: Formalin-fixed, paraffin-embedded tissue block; or 3 unstained glass, "positively charged" slides with 4-microns formalin-fixed, paraffin-embedded tissue

Additional Information: One slide will be stained with hematoxylin and eosin and returned.


If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:

Immunohistochemical (IHC)/In Situ Hybridization (ISH) Stains Request (T763)

Oncology Test Request (T729)

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Wet/frozen tissue
Cytology smears
Nonformalin fixed tissue
Nonparaffin embedded tissue
Noncharged slides
ProbeOn slides

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Special Ambient (preferred)

Useful For
Suggests clinical disorders or settings where the test may be helpful

Identification of neoplasms expressing programmed cell death 1-ligand 1

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Programmed cell death 1-ligand 1 (PD-L1), also known as B7 homolog 1 (B7-H1) or CD274, is a transmembrane protein involved in the regulation of cell-mediated immune responses through interaction with the receptor programmed death protein-1 (PD-1). PD-L1 has been identified as both a prognostic and theranostic marker in a variety of neoplasms. Overexpression of PD-L1 has been observed in carcinomas of the bladder, lung, gastric and gastroesophageal junction, colon, ovary, breast, kidney, and melanoma.

Provides information to assist in interpretation of the test results

The results of the test will be reported in form of scores. The scoring system is based on type and origin of tumor. If additional interpretation or analysis is needed, order PATHC / Pathology Consultation along with this test.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Preclinical studies suggest that positive programmed cell death 1-ligand 1 (PD-L1) immunohistochemistry in tumor cells may predict tumor response to therapy with immune checkpoint inhibitors. This result should not be used as the sole factor in determining treatment, as other factors (eg, tumor mutation burden and microsatellite instability) have also been studied as predictive markers.


This test has been validated for non-decalcified paraffin-embedded tissue specimens fixed in 10% neutral-buffered formalin. This assay has not been validated on tissues subjected to the decalcification process or the use of alternative fixatives for bone and bone marrow specimens or cell blocks.


Age of a cut paraffin section can affect immunoreactivity. Stability thresholds vary widely among published literature and are antigen dependent. Best practice is for paraffin sections to be cut within 6 weeks.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Garcia A, Recondo G, Greco M et al: Correlation between PD-L1 expression (clones 28-8 and SP263) and histopathology in lung adenocarcinoma. Heliyon. 2020 Jun;6(6):e04117

2. Kintslera S, Cassataroa MA, Drosch M, Holenya P, Knuechel R, Braunschweig T: Expression of programmed death ligand (PD-L1) in different tumors. Comparison of several current available antibody clones and antibody profiling. Ann Diagn Pathol. 2019 Aug;41:24-37

3. O'Malley DP, Yang Y, Boisot S, et al: Immunohistochemical detection of PD-L1 among diverse human neoplasms in a reference laboratory: observations based upon 62,896 cases. Mod Pathol. 2019 Jul;32(7):929-942

4. Koppel C, Schwellenbach H, Zielinski D, et al: Optimization and validation of PD-L1 immunohistochemistry staining protocols using the antibody clone 28-8 on different staining platforms. Mod Pathol. 2018 Nov;31(11):1630-1644

5. Phillips T, Simmons P, Inzunza HD, et al: Development of an automated PD-L1 immunohistochemistry (IHC) assay for non-small cell lung cancer. Appl Immunohistochem Mol Morphol. 2015 Sep;23(8):541-549

Method Description
Describes how the test is performed and provides a method-specific reference

Immunohistochemistry on sections of paraffin-embedded tissue using programmed cell death 1-ligand 1 (PD-L1) clone 28-8.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

5 to 7 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

Until reported

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
288PD PD-L1 (28-8), SemiQuant IHC, Manual 85148-5
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
609995 Interpretation 83056-2
609996 Participated in the Interpretation No LOINC Needed
609997 Report electronically signed by 19139-5
609998 Material Received 81178-6
609999 Disclaimer 62364-5
610000 Case Number 80398-1

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
New Test 2021-10-05