|
Test ID: Antigen Receptor Gene Rearrangements
|
|
IGH-TCR Gene Rearrangement
|
|
|
|
Useful For
|
Assessment of Clonality at the Immunoglobulin and T Cell Receptor Loci in patients with lymphoproliferative disorders (LPDs). Gene rearrangements of the antigen receptor genes occur during the lymphoid proliferation. Lymphoproliferative disorders (LPDs) occur when the normal mechanisms of control of proliferation of lymphocytes break down, resulting in autonomous, uncontrolled proliferation of lymphoid cells and typically leading to lymphocytosis and/or lymphadenopathy, and sometimes to involvement of extranodal sites, e.g. bone marrow. Malignant LPDs are clonal in nature, resulting from the uncontrolled proliferation of a single transformed cell, e.g. lymphoma; and non-malignant LPDs are polyclonal lymphoproliferative disorders may result from conditions including (a) infections—lymphocytosis is commonly caused by viral infections, e.g. Epstein–Barr virus (EBV).
|
|
Method name and description
|
PCR based analysis of genomic DNA prepared from blood or marrow for rearrangements of the immunoglobulin heavy chain and T cell receptor genes is used to identify lymphocyte populations derived from a single cell by detecting the V-J gene rearrangements present within the antigen loci that are unique in length and sequence for each cell and provide a clonal signature of lymphoproliferative disease.
These tests amplify DNA using multiple consensus primers that target the conserved framework (FR) and joining (J) regions which lie either side of the diversity region. They can detect most clonal T & B cell populations and provide clinical utility with respect to identification of clonality in atypical lymphoproliferative disorders and to support a differential diagnosis between reactive & clonal lesions.
|
|
Reporting name
|
Antigen Receptor Gene Rearrangements Final Report
|
|
Clinical information
|
Antigen receptor gene rearrangement reports are a cornerstone of modern hematopathology. They provide molecular evidence to distinguish between a "reactive" immune response (polyclonal) and a "neoplastic" malignancy (monoclonal).
|
|
Aliases
|
B-Cell Testing
T-Cell Testing
Lymphoid Clonality
Clonality Assessment for Leukemia
TCR Gene rearrangement
TCR Gamma Gene rearrangement - Clonality M111.2
TCR Beta Gene rearrangement - Clonality M225.3
Lymphoma IGH Gene rearrangement - Clonality M109.1
|
|
|
Specimen type / Specimen volume / Specimen container
|
|
Specimen Type
|
Specimen Volume
|
Container/Tube
|
|
Whole Blood (BL)
|
Adult: minimum 3 mL
Child : minimum 1ml
|
Lavender top (EDTA)
|
|
Bone Marrow (BM)
|
Adult: minimum 3 mL
Child : minimum 1ml
|
Lavender top (EDTA)
|
|
gDNA
|
3 µg of gDNA (stored at 2°C to 8°C and shipped at ambient temperature
|
2ml sterile cryovial
|
|
FFPE
|
Formalin-fixed paraffin embedded tissue or slides (stored and shipped at ambient temperature)
|
Embedded tissue or Slides
|
|
|
Collection instructions / Special Precautions / Timing of collection
|
Collection Instructions
When collecting specimens for molecular testing for IGH/TCR clonality assessment, strict adherence to collection protocols is required to preserve the integrity of the DNA.
Patient Preparation:
Previous allogeneic bone marrow transplant can yield discordant leukocyte DNA; note clearly in clinical details.
Specimen Type:
|
Specimen Type
|
Container/Tube
|
Specimen Volume
|
Patient Preparation / Notes
|
|
Whole Blood –BL
|
Lavender-top EDTA tube
|
Adult: minimum 3 mL
Child : minimum 1ml
|
Blood is often the preferred specimen for routine monitoring.
|
|
Bone Marrow-BM
|
Lavender-top EDTA tube
|
Adult: minimum 3 mL
Child : minimum 1ml
|
Blood is often the preferred specimen for routine monitoring.
|
|
gDNA
|
2ml sterile cryovial
|
3 µg of gDNA (stored at 2°C to 8°C and shipped at ambient temperature
|
|
|
FFPE
|
Embedded tissue or Slides
|
Formalin-fixed paraffin embedded tissue or slides (stored and shipped at ambient temperature)
|
|
|
|
Relevant clinical information to be provided
|
Submit With Order
- Clinical indication and relevant history
- Document if prior allogeneic bone marrow transplant present (may confound results).
- Patient and Diagnosis Information
- Monitoring and Treatment History
- Summary of Most Critical Information
|
|
Storage and transport instructions
|
The specimens should be transported to Central Processing (CP) in the Qatar Rehabilitation Institute (QRI), 3rd floor, HBK MC in cool box with ice pack.
|
Specimen Type
|
Container/Tube
|
Volume Required
|
Storage Before Transport
|
Patient Preparation / Notes
|
|
Whole Blood
|
Lavender-top EDTA tube
|
Adult: Minimum 3ml
Child :Minimum 1ml
|
Room temperature; Preferred 2–8 °C
Within 24 hours of the patient being bled (Preferred if delay expected)
|
2–8 °C (refrigerated), upright, avoid shaking;
Within 24 hours of the patient being bled
|
|
Bone Marrow
|
Lavender-top EDTA tube
|
Adult: Minimum 3ml
Child: Minimum 1ml
|
|
gDNA
|
2ml sterile cryovial
|
3 µg of gDNA (stored at 2°C to 8°C and shipped at ambient temperature
|
|
|
FFPE
|
Embedded tissue or Slides
|
Formalin-fixed paraffin embedded tissue or slides (stored and shipped at ambient temperature)
|
|
|
|
Specimen Rejection Criteria
|
Specimens will be rejected under the following conditions:
- Wrong specimen container.
- Leaking or contaminated container.
- Unlabeled specimen.
- Mislabeled specimen.
- Improperly filled request form.
- No specimen types.
- No physician stamps.
- No clinical history/data documented.
- The information written on the tube does not match the data on the request form, and there is no response when calling the ward for correction.
- No request/electronic order received.
- Excessive hemolysis or clotted blood.
- Delayed specimens that are judged unsuitable for analysis.
|
|
|
Turnaround time / Days and times test performed / Specimen retention time
|
Turn Around Time
21 Working Days. (Working Days: Sunday to Thursday from 7:00 am to 3:00 pm)
Specimen Retention Time
Samples are stored one year only
|
|
|
