B-CELL CLONALITY (IGH AND IGK) AND T-CELL CLONALITY (GAMMA)

Synonyms

T-CELL RECEPTOR GENE REARRANGEMENT B-CELL RECEPTOR GENE REARRANGEMENT.

  • Tech Only CPT
  • Tech Pro CPT 81261, 81264, 81342
  • PowerPath Code S/O PAML
  • Schedule Tuesday, Wednesday
  • Turn Around Time 7-10 Days
  • Disease State Lymphoma
  • Methodology PCR

Specimen Requirements

Container Type: Lavender top (EDTA); paraffin embedded tissue and/or slidesSpecimen Type: Whole blood, bone marrow; formalin fixed paraffin embedded tissueAlternate Specimens: ACD or sodium citrate whole blood (lavender, yellow, or blue top tube)Preferred Volume: 5 mL whole blood, 1 mL bone marrow; 1 paraffin embedded tissue block or 6 unstained 7-micron slides with an additional H&E stained slide containing at least 50% tumor cells.Minimum Volume: 3 mL whole blood, 0.5 mL bone marrow; 1 paraffin embedded tissue block or 4 unstained 7-micron slides with an additional H&E stained slide containing at least 20% tumor cells.Whole blood bone marrow: Submit original unopened tube only. FFPE: Prepare H&E slide if submitting unstained 7-micron slides.

Clinical Signifigance

During normal B-cell and T-cell development and maturation, the immunoglobulin (Ig) heavy-and light-chain (Kappa and Lambda) genes or the T-cell receptor (TCR), alpha and beta genes or gamma and delta genes, respectively, undergo a series of rearrangements to produce a unique antigen receptor with specificity to a discrete antigen. In a healthy person, B- and T-cell development results in a spectrum of mature B- and T-cells that can respond to essentially any antigen encountered by the individual. In B- or T-cell lymphoproliferative disorders, the neoplastic B- or T-cell population shares the same Ig or TCR rearrangement pattern and serves as a marker for monoclonality that can be detected by PCR and capillary electrophoresis. In typical reactive populations, no single rearrangement predominates, yielding a detectable polyclonal pattern. Therefore, a prominent Ig or TCR gene rearrangement profile (IGH, IGK, or TCRG in this assay) is suggestive for lymphoid malignancy in the appropriate clinical and pathologic setting. Detection of the same profile could be used for monitoring a patient with persistent neoplasm.

Required Patient Info

Surgical Pathology Report

Storage and Transportation

Whole blood, bone marrow: Store and transport at room temperature or refrigerated if delay of more than 72 hours. Indicate source. FFPE: Transport paraffin embedded, formalin fixed tissue block, or slides at 20-25C. Protect paraffin block from excessive heat. Ship in cooled container during summer months. Include surgical pathology report.

Cause for Rejection

Whole blood in sodium heparin, serum/plasma, grossly hemolyzed, frozen whole blood or bone marrow, specimens in leaky containers or over 5 days old and samples not received in the original unopened collection tubes. No tumor in tissue. Specimens fixed/processed in alternative fixatives (alcohol, Prefer®)

Comments

The detection of clonality does not always imply the presence of a malignancy. Some clinically benign proliferations could have a clonal origin (e.g. benign monoclonal gammopathies, T-lymphocytosis, benign cutaneous T-Cell proliferations, etc.). False-negative results might be possible due to improper primer annealing.