F BURKITT; FP BURKITT
C-MYC 8q24, BCL2 t(14;18), BCL6 3q27
"double hit" B-cell lymphoma
Fluorescence in situ Hybridization (FISH)
2.0 mL (min. 1.0 mL) peripheral blood in sodium heparin, EDTA accepted
1.0 mL (min. 0.5 mL) bone marrow in sodium heparin, EDTA accepted
5 mm^3 fresh tissue or 3.0 mL (min. 2.0 mL) FNA in MPLN RPMI media
10% neutral buffered formalin fixed paraffin embedded tissue
Whole blood and bone marrow, ship ambient
Fresh tissue, FNA or paraffin embedded tissue, ship in a Styrofoam container with a cool/refrigerated pack (Do not allow cool pack to directly contact sample)
Clotted specimen; Specimen exposed to extreme temperature; Anticoagulant toxic to cells; Insufficient number of cells; Improper fixative
This small, multiprobe panel contributes to the distinction of Burkitt’s from large B-cell lymphoma on problematic specimens demonstrating borderline morphologic or immunophenotypic features, limited sample volume, or zero to low probability for successful karyotyping. Burkitt’s lymphoma characteristically demonstrates a very high Ki67 staining index, strong CD10, and positive bcl-6 staining with negative staining for bcl-2. Burkitt’s lymphomas typically reveal MYC translocation partnered to Ig heavy or light chain genes in the background of an otherwise simple karyotype. Rarely, Burkitt’s lymphomas may lack MYC translocation.
Among large B-cell lymphomas, MYC translocation is demonstrated in a small but significant subset, almost always in the background of a complex karyotype, presumably representing secondarily acquired genetic change. Frequently, these MYC+ large B-cell lymphomas are also positive for BCL2 or BCL6 rearrangements. Incomplete clinical evidence suggests that MYC+ large B-cell lymphomas may benefit from Burkitt-like chemotherapeutic regimens.
When confronted with fresh or paraffin embedded tissue specimens containing CD10+ Ki67+(high) bcl2- B-cell neoplasia, this multiprobe FISH panel often facilitates distinction of Burkitt’s from large B-cell lymphoma.