All IHC stains will include a positive control tissue

• Granzyme B is used (often in a panel with T1A-1 and/or perforin) to identify cytotoxic (NK-like) T-cell lymphomas, especially enteropathy associated T-cell lymphomas, and subcutaneous panniculitis-like T-cell lymphoma. These antibodies also identify true NK cell lymphomas/leukemias, including aggressive NK-cell leukemia/lymphoma and extra-nodal NK/T-cell lymphoma, nasal type
• NK cell lymphomas are usually aggressive, and are associated with rapid progression, treatment failures, and relapses; therefore, accurate diagnosis is essential
• Some studies report an associated of nasal-type NK cell lymphomas with EBV, and are more common in Asian and Latin American countries
• P53 is also expressed in a high percentage of these types of lymphomas
• Granzyme B should be used in a panel with other T cell markers, as well as with CD56 and T1A-1 and or perforin

Submit a formalin-fixed, paraffin-embedded tissue

Formalin-fixed, paraffin-embedded (FFPE) tissue block

Tissue section mounted on a charged, unstained slide

Ambient (preferred)

• Unlabeled/mislabeled block
• Insufficient tissue
• Slides broken beyond repair

Immunohistochemical staining and microscopic examination

If requested, an interpretive report will be provided

Specifications

• Granzyme B is a granule-associated serine protease type of protein, found in cytotoxic T lymphocytes (CTL) and in natural killer (NK) cells
• Granzyme B and perforin are essential for apoptosis and immune-mediated cell death of target cells via induction of cell membrane perforation
• Granzyme B expression is evidence of an activated state of CTL and NK cells, and is therefore useful in identifying related lymphomas associated with these types of cells
• Expression of this marker has been associated with a poor prognosis in nodular sclerosis or mixed cellularity Hodgkin's disease

 Staining pattern

• Granular cytoplasmic staining

References

1. Gall K et al: Sinonasal NK/T-cell lymphomas in the United States. Am J Surg Pathol 24(11):1511-1517, 2000.
2. Natkunam Y et al: Aggressive cutaneous NK and NK-like T-cell lymphomas; clinicopathologic, immunohistochemical and molecular analyses of 12 cases. Am J Surg Pathol 23(5): 571-581, 1999.
3. Quintanilla-Martinez L et al: Histological and Immunophenotypic profile of nasal NK/T cell lymphomas from Peru: high prevalence of p53 over-expression. Hum Pathol 30:849-855, 1999.
4. Kumar S et al: Subcutaneous panniculitic T-cell lymphoma is a tumor of cytotoxic T lymphocytes. Hum Pathol 29:397-403, 1998.