Test Catalog

Test ID: CD273    
CD273 (PD-L2) Immunostain, Technical Component Only

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

Differentiation of primary mediastinal large B-cell lymphoma (PMLBL) from diffuse large B cell-lymphoma (DLBCL)

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

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

CD273 also known as programmed cell death 1-ligand 2 (PD-L2) regulates T-cell activation in addition to immune responses and is a member of the B7 family of cell surface ligands. CD273 expression is a specific marker of primary mediastinal large B-cell lymphoma (PMLBL) and it can be used to distinguish PMLBL from diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS), which occurs in the mediastinum. These 2 entities have distinct clinical behavior and respond uniquely to differently therapies.

Interpretation Provides information to assist in interpretation of the test results

This test includes only technical performance of the stain (no pathologist interpretation is performed). If diagnostic consultation by a pathologist is required order PATHC / Pathology Consultation.


The positive and negative controls are verified as showing appropriate immunoreactivity. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request. Contact 855-516-8404.


Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.

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

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 fresh.

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

1. Chong LC, Twa DDW, Mottok A, et al: Comprehensive characterization of programmed death ligand structural rearrangements in B-cell non-Hodgkin lymphomas. Blood 2016;128(9):1206-1213

2. Shin S, Jeon YK, Kim P, et al: Clinicopathologic Analysis of PD-L1 and PD-L2 Expression in Renal Cell Carcinoma: Association with Oncogenic Proteins Status. Ann Surg Oncol 2016;23:694-702

3. Shi M, Roemer MGM, Chapuy B, et al: Expression of Programmed Cell Death 1 Ligand 2 (PD-L2) Is a Distinguishing Feature of Primary Mediastinal (Thymic) Large B-cell Lymphoma and Associated With PDCD1LG2 Copy Gain. Am J Surg Pathol 2014;38(12):1715-1723