Test Code #
CPT Code(s) #
T-Cell Receptor Gene Rearrangements Profile, y and b
If Profile, Includes Tests:
Type of Study:
• Positive (either Monoclonal or Clonal)
• Negative (either Oligoclonal or Polyclonal)
Assay performed once per week. Report availability is one week from the time of specimen receipt.
Whole blood, bone marrow, formalin-fixed, paraffin-embedded (FFPE) tissue block or slides, fresh or frozen tissue are acceptable specimens.
Maintain blood, bone marrow or tissue in RPMI at 2ºC to 8ºC; FFPE specimens at room temperature; tissue at -80ºC.
An assessment of T-cell clonality is an important part of the evaluation of suspected lymphoproliferative disorders. Historically, Southern blot studies for T-cell receptor beta chain (TCRB) rearrangements have been considered to represent the gold standard for T-cell clonality evaluation. Southern blot studies are labor-intensive and time-consuming for the laboratory and often are impractical for routine practice as they require fresh or frozen tissue and cannot be performed on formalin-fixed, paraffin-embedded (FFPE) material. PCR assays for T-cell receptor gamma chain (TCRG) and/or TCRB rearrangements offer the ability to assess clonality from standard FFPE, but until recently, PCR studies have been limited by a higher false negative rate compared to Southern blot studies. T-cell clonality assay that employs primers for both TCRB and TCRG, a combination that has been shown to detect clonality in essentially 100% of T-cell prolymphocytic leukemias, T-cell large granular lymphocyte disorders, and peripheral T-cell lymphomas, unspecified, with somewhat lower rates reported in angioimmunoblastic T-cell lymphomas and anaplastic large cell lymphoma. These assays are designed for detection of clonal T-cell populations in suspected lymphoproliferative disorders using fresh, frozen, or FFPE tissue.