Immunoglobulin Heavy Chain (IGH) Clonality Detection by PCR and Capillary Electrophoresis

CPT Code(s)

81261, G0452

Synonym(s)

IGH Gene Clonality Detection, B-cell Receptor IGH Gene Rearrangement, IGH, Molecular, Immunoglobulin Heavy Chain (IGH) Clonality Detection

Performed

Molecular Diagnostics Laboratory

Clinical Indication and Relevance

The assay is useful to assist with the diagnosis of B-cell malignancies. The assay can also be used to detect minimal residual disease in follow-up samples.

Methodology

DNA is isolated and amplified by PCR using BIOMED-2 primers targeting the VH framework 1, 2, 3, DH and JH sequences of the IGH gene. The gene rearrangements are detected by analyzing the PCR products by capillary gel electrophoresis. The assay sensitivity for detection of clonal B-cell populations is 5% of lymphocytes.

Minimum Specimen Requirements

Collect

  • Peripheral blood (PB): 2-5 mL, in purple top (sodium EDTA) tube
  • Bone marrow (BM): 1-3 mL, drawn into a syringe containing anticoagulant and then
    delivered in purple top tube (EDTA).
  • For Fresh or frozen tissue:  “3mm3 ”of tissue is required. Fresh tissue should be placed in culture medium for transportor snap frozen (see transport section below).
  • Formalin-fixed, paraffin-embedded (FFPE) tissue blocks: send tissue block to the lab, or
    contact lab for instructions regarding cutting paraffin sections for molecular studies.

 

Transport

  • PB or BM sample: Deliver immediately at 2-8°C (wet ice or cold packs). Do not freeze.
  • Fresh tissue samples should be delivered at room temperature in RPMI culture medium within 3 hours of collection, or snap frozen in liquid nitrogen at -70°C and packed in
    dry ice for delivery. Please do not allow frozen tissues to thaw.
  • Formalin-fixed paraffin embedded (FFPE) tissue blocks and slides can be delivered at controlled temperatures, not to exceed 30C.

 

Stability
PB or BM samples: ambient – 1 hour; refrigerated – 48 hours.

Unacceptable Samples

    • Serum or plasma; frozen PB or BM; clotted blood; severely hemolyzed samples
    • Paraffin tissue fixed in Zenker’s, B5, or Bouin’s fixatives
    • Bone marrow biopsy decalcified in formic acid

Turnaround time

Seven working days.
*The sample must be received by 5:00 PM Thursday to make the next clinical run.

View Requisition Sheet