Test Code #
CPT Code(s) #
T-Cell Receptor Gene Rearrangements Profile, y and b
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.