B-Cell Clonality Analysis (IgH Gene Rearrangements)

Additional Information:

Epic order code: LAB5640

CPT Code(s):

  • 81261
  • 88381 (FFPE)

Specimen Requirements:

Paraffin-embedded tissue; send one tissue block or 4 unstained slides. Ship the specimen at 20° - 25° C. Tissues that are fixed in formalin substitute are unacceptable. Tissue that does not contain lymphocytes is not accepted. Ship all tissue specimens with a cold pack in summer months.

Blood or bone marrow in an EDTA or ACD tube; one 3 mL of blood or 1 mL of bone marrow shipped at 4° C is acceptable. Severely hemolyzed whole blood and/or clotted or frozen whole blood/bone marrow specimens are not accepted.

Fresh tissue that is at least a 5 mm cube, shipped frozen or on ice in RPMI 1640, is accepted.

Cell pellets, at least 10 6-cells shipped at 4° C, are acceptable.

Use:

Clonality analysis of B-cell populations can aid in the diagnosis of lymphoproliferative disorders. This test is used to support or refute the diagnosis of B-cell lymphomas/leukemias.

Methodology:

Polymerase chain reaction/fluorescent DNA fragment analysis

Reported:

5 - 10 days

Reference Values:

Negative; interpretative report

Performed:

Monday - Friday

Interpretation Data:

B-Cell Clonality

  • Positive: A monoclonal B-cell population is detected.
  • Negative: A monoclonal B-cell population is not detected.
  • Undetermined: Refer to the interpretation notes.
  • QNS: There is not sufficient material to perform the test.

Note: The test is performed by using Invivoscribe Technologies’ Gene Rearrangement Assay, which targets the joining region and all three of the conserved framework regions (FR 1 – 3) within the IGH gene. False negatives may be due to somatic mutations in the IgH gene at or near the primer binding sites. In N-region diversity, the clonal population is lower than detection limitation, and may also be due to the poor sample quality of paraffin-embedded tissue. Thus, the presence of a clonal B-cell population in the specimen cannot be entirely excluded by the negative PCR results. Correlation with morphology and immunophenotype is recommended.