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Alias/Synonym: Late Stage B-Cells, Plasma Cells, Activated T-Cells

CPT Code: 88342

Specimen Type, Preferred:
Formalin fixed paraffin embedded tissue
Specimen Type, Alternate:
Sample Quantity, Preferred:
1 block
2 slides
Sample Quantity, Minimum:
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:
Rejection Criteria:
No liquid specimens.
Uncharged slides
Clinical Significance:
MUM-1 (Multiple Myeloma 1 or Interferon Regulatory Factor 4 protein) is expressed in late plasma cell directed stages of B cell differentiation and in activated T cells, suggesting that MUM-1 may serve as a marker for lympho-hemopoietic neoplasms derived from these cells. The morphologic spectrum of MUM-1 expressing cells has been found to range from that of a centrocyte to that of a plasmablast/plasma cell. Consequently the histogenic value of MUM-1 may be to provide a marker to aid in the identification of the transition from BCL-6 positive (germinal center B cells) to CD138 positive (immunoblasts and plasma cells).
Turnaround Time:
1 day(s)
Reference Ranges: