Test Code

I ALK

Associations

Anaplastic large cell Lymphoma

Methodology

Immunohistochemistry

Turnaround Time

2 days

Specimen Requirements

Paraffin embedded tissue block
3 slides (3-5 uM) per marker on adhesion glass

Specimen Stability

Storage & Handling

Ship ambient. Protect from extreme temperature with an ice pack. Separate ice pack from specimen.

Causes for Rejection

Inadequate fixation; Improper labeling

Description

Anaplastic lymphoma kinase-1 recognizes a formalin resistant epitope in both the p80 protein, identified as a hybrid of the anaplastic lymphoma kinase (ALK) protein and the nucleophosmin (NPM) protein and the 200 kD normal ALK proteins. ALK-1 may also recognize any ALK protein chimeric produced as a result of variant translocations involving the ALK gene on chromosome 2.
ALK-1 recognizes varying degrees of ALK expression in both the cytoplasm and nucleus of anaplastic lymphoma cells. ALK protein expression is substantially specific for anaplastic lymphomas, except for weak expression in some normal cells in the central nervous system including neurons, glial cells and endothelial cells. ALK expression may also be seen in inflammatory myofibroblastic tumors and rare rhabdomyosarcomas.

References

1. Pulford K et al.(1997). Detection of anaplastic lymphoma kinase (ALK) and nucleolar protein nucleophosmin (NPM)-ALK proteins in normal and neoplastic cells with the monoclonal antibody ALK1. Blood.89(4):1394-1404.
2. Griffin CA et al.(1999). Recurrent involvement of 2p23 in inflammatory myofibroblastic tumors. Cancer Res.59(12):2776-2780.
3. Falini B et al. (1998). ALK expression defines a distinct group of T/null lymphomas (“ALK lymphomas”) with a wide morphological spectrum. Am J Pathol. 153(3):875-86.