TCRB + TCRG T-cell clonality assay and IGH + IGK B-cell clonality assay

Unstained formalin fixed paraffin embedded (FFPE) tissue sections on uncoated slides (8 sections of 8 µm thickness for large resection / excision specimens or 15 sections of 5 µm thickness for small biopsy specimens) together with 1 H&E stained slide for each specimen will be required for this assay. 

The tissue sections should ideally contain at least 20% of lymphoid cells for T-cell clonality assay and at least 10% lymphoid cellularity for B-cell clonality assay. Specimens with lower lymphoid cellularity can still be accepted for testing but the sensitivity for clonality detection may be reduced. 

Paraffin embedded tissue blocks are also acceptable. 

DNA is accepted only if FFPE tissue is not available. The laboratory only accepts DNA that is extracted or isolated in a CAP-accredited, CLIA-certified or equivalent laboratory. Please call the lab for additional details.

Rearrangement of the immunoglobulin and antigen receptor genes occur during ontogeny of T & B lymphocytes producing products that are unique in sequence and length for each cell. Polymerase chain reaction (PCR) based detection of such gene rearrangement products coupled with analysis of their fragment size using capillary electrophoresis allows for the determination of the presence of T- or B-cell clonal populations. This is useful as an adjunct test to help evaluate the nature of lymphoid proliferations. 

The T-cell and B-cell clonality assays are such PCR based assays that use multiple consensus DNA primers in a multiplex fashion, targeting the conserved genetic regions within the T-cell receptor beta (TCRB) and gamma (TCRG) genes and the immunoglobulin heavy (IGH) and kappa light chain (IGK) genes respectively. The presence of a clonal gene rearrangement product can help confirm the presence of a lymphoid malignancy in a lesion with concordant clinical, histological and immunophenotypic features. 

This assay can be used to determine the presence of a clonal T-cell antigen receptor beta (TCRB) or gamma (TCRG) gene rearrangement in a T-cell proliferation or clonal immunoglobulin heavy (IGH) or kappa light chain (IGK) gene rearrangement in a B-cell proliferation.

Specimens should be sent to 20 College Road, Academia building, Diagnostic Tower Level 10, Histopathology Lab, Department of Anatomical Pathology, Singapore General Hospital, Singapore 169856.

Any queries can be directed to the Anatomical Molecular Laboratory (ATOM) at (65) 6576 7191 or Histopathology Laboratory at (65) 6321 4956.

Multiplexed PCR based assay using multiple consensus DNA primers targeting the conserved genetic regions within the T-cell receptor beta (TCRB) and gamma (TCRG) genes and the immunoglobulin heavy (IGH) and kappa light chain (IGK) genes.

Presence or absence of clonal rearrangements in T-cell receptor or immunoglobulin genes. The electropherograms will be issued together with the test report.

10 working days

Every Monday