PAX-5

Alias/Synonym: B-Cell Transcription Factor

CPT Code: 88342

Includes:

Specimen Type, Preferred:

Formalin fixed paraffin embedded tissue

Specimen Type, Alternate:

Sample Quantity, Preferred:

1 block

2 slides

Sample Quantity, Minimum:

N/A

Transport Container:

Paraffin block

Unstained slides

Transport Temperature:

Room temperature

Collection Instructions:

Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.

Slides should be positively charged and cut at 3-4 microns for each stain/antibody ordered.

Specimen Stability:

N/A

Rejection Criteria:

No liquid specimens.

Uncharged slides

Clinical Significance:

Pax genes are a family of developmental control genes that encode nuclear transcription factors and have been implicated in the control of mammalian development. PAX-5 encodes for B-cell specific activator protein (BSAP), which is a B cell specific transcription factor that is expressed in pro B cells, pre-B and mature B cells, and subsequently in all stages of B cell development until the plasma cell stage in which it is downregulated. It is positive in most B cell malignancies, and is very helpful for evaluation of B-cell neoplasms after rituximab therapy which may downregulate CD20 expression. It is usually positive in Reed-Sternberg cells of Hodgkin lymphoma, and may be present in Merkel cell carcinoma and small cell carcinoma.

Limitations:

Turnaround Time:

1 day(s)

Reference Ranges:

N/A

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