Determining whether a B cell or plasma cell population is polyclonal or monoclonal using paraffin-embedded specimens
Identifying neoplastic cells as having B-cell or plasma cell differentiation
Monitoring for a persistent neoplasm by detecting an immunoglobulin gene rearrangement profile similar to that from a previous neoplastic specimen
Polymerase Chain Reaction (PCR)
B-Cell Clonality by PCR
B-Cell Gene Rearrangement
B-Cell Immunoglobulin Gene Rearrangement
IGH
Immunoglobulin Gene Rearrange (PCR)
Lymphoma vs Benign Process
B Cell Gene Rearrangement
Tissue, Paraffin
Specimen Type: Paraffin-embedded bone marrow aspirate clot or paraffin-embedded tissue
Container/Tube: Paraffin block
Specimen Volume: Minimum of 4 slides, 10 um preferred
See Specimen Required
Bone marrow biopsies Paraffin shavings Decalcified tissue Tissue that has not been formalin fixed/paraffin-embedded | Reject |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Tissue, Paraffin | Ambient (preferred) | ||
Refrigerated |
Determining whether a B cell or plasma cell population is polyclonal or monoclonal using paraffin-embedded specimens
Identifying neoplastic cells as having B-cell or plasma cell differentiation
Monitoring for a persistent neoplasm by detecting an immunoglobulin gene rearrangement profile similar to that from a previous neoplastic specimen
The immunoglobulin genes (heavy, kappa, and lambda) are comprised of numerous discontinuous coding segments. As B cells develop, the segments are rearranged such that each mature B cell or plasma cell has a unique rearrangement profile. Other cell types usually retain the unrearranged gene structures. Clonal expansion of any B cell or plasma cell will result in a population of cells that all contain an identical immunoglobulin gene rearrangement profile.
Reactive B cell or plasma cell expansions are polyclonal, with each clone containing relatively few cells and no single clone predominating. Conversely, neoplastic clones are generally large such that the clonal cells are the predominant B cells or plasma cells present.
In the appropriate clinical and pathologic setting, detection of a prominent immunoglobulin gene rearrangement profile may be equated to the presence of a neoplastic B-cell or plasma cell clone.
An interpretive report will be provided and include whether the specimen was positive, negative, or indeterminate for a clonal B-cell population.
An interpretive report will be provided.
The interpretation of the presence or absence of a predominant immunoglobulin gene rearrangement profile is sometimes subjective. These results must always be interpreted in the context of other clinicopathologic information to determine the significance of the result.
The detection of a clonal Ig gene rearrangement by this test is not synonymous with the presence of a B-cell or plasma cell neoplasm.
This test is neither 100% sensitive nor 100% specific.
False-negative results may occur if the immunoglobulin gene has numerous point alterations introduced during expansion in a follicle center (somatic hypermutation) such that none of the polymerase chain reaction primers will bind. False-negative results will also occur if the clonal cells have not rearranged the immunoglobulin genes being evaluated or are present below the sensitivity level of the assay (sensitivity is quite variable but the assay requires that at least 1% to 5% of the nucleated cells present be clonal). False-positive results are rare but may occur if a predominant clone (or small number of clones) is produced or sampled from a polyclonal expansion.
The test does not provide information regarding:
-The differentiation of the clonal cell population (neoplastic cells other than B cells or plasma cells may occasionally have Ig gene rearrangements)
-Whether a prominent clone is physiologic or neoplastic
1. Liu H, Bench AJ, Bacon CM, et al. A practical strategy for the routine use of BIOMED-2 PCR assays for detection of B- and T-cell clonality in diagnostic haematopathology. Br J Haematol. 2007;138(1):31-43
2. Van Krieken JH, Langerak AW, Macintyre EA, et al. Improved reliability of lymphoma diagnostics via PCR-based clonality testing: report of the BIOMED-2 Concerted Action BHM4-CT98-3936. Leukemia. 2007;21(2):201-206
3. Bruggemann M, White H, Gaulard P, et al. Powerful strategy for polymerase chain reaction-based clonality assessment in T-cell malignancies Report of the BIOMED-2 Concerted Action BHM4 CT98-3936. Leukemia. 2007;21(2):215-221
4. van Dongen JJ, Wolvers-Tettero IL. Analysis of immunoglobulin and T-cell receptor genes. Part II: Possibilities and limitations in the diagnosis and management of lymphoproliferative diseases and related disorders. Clin Chim Acta. 1991;198(1-2):93-174
5. Coad JE, Olson DJ, Lander TA, et al. Molecular assessment of clonality in lymphoproliferative disorders: I. Immunoglobulin gene rearrangements. Mol Diagn. 1996;1(4):335-355
6. Kokovic I, Novakovic BJ, Novakovic S. Diagnostic value of immunoglobulin k light chain gene rearrangement analysis in B-cell lymphomas. Int J Oncol. 2015;46(3):953-962. doi:10.3892/ijo.2014.2790
Genomic DNA is extracted from all specimens. In the polymerase chain reaction (PCR) assay, a total of 34 upstream and 5 downstream primers are used. The primers are designed to amplify fragments from all theoretical rearrangements of the immunoglobulin heavy and kappa light chain genes. Each unique rearrangement should produce PCR fragments of unique sizes. The primers cannot amplify anything if the immunoglobulin genes are not rearranged because the distance is too great. The primers are labeled with a fluorescent tag so that the PCR product can be detected. The PCR fragments are analyzed by capillary gel electrophoresis using the Applied Biosystems 3500xL machine for fragment size and amount.(Langerak AW, Groenen PJTA, Bruggemann M, et al. EuroClonality/BIOMED-2 guidelines for interpretation and reporting of Ig/TCR clonality testing in suspected lymphoproliferations. Leukemia. 2012;26(10):2159-2171)
Monday through Friday
This test was developed using an analyte specific reagent. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.
81261-IGH (Immunoglobulin heavy chain locus) (eg, leukemias and lymphomas B-cell), gene rearrangement analysis to detect abnormal clonal populations; amplified methodology (eg. polymerase chain reaction)
81264-IGK (Immunoglobulin kappa light chain locus) (eg, leukemia and lymphoma, B-cell) gene rearrangement analysis, evaluation to detect abnormal clonal populations
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
BCGET | Immunoglobulin Gene Rearrange, Ts | 61113-7 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
38342 | Final Diagnosis: | 22637-3 |
610556 | Signing Pathologist | 19139-5 |
Change Type | Effective Date |
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New Test | 2024-11-04 |