F BCL6; FP BCL6
BCL6 gene; 3q27 rearrangement
B-cell lymphoma, Non-Hodgkin lymphoma (NHL), Diffuse large B cell, Follicular 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 (FFPE)
Whole blood and bone marrow, ship ambient
Fresh tissue, FNA or FFPE 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
FISH results indicate whether rearrangement is present or absent. In a normal cell, two fusion (orange/green, or yellow) signals will be observed representing two intact copies of chromosome 3. In a cell that has a translocation with the breakpoint within 3q27, one fusion signal, one orange signal, and one green signal will be found.
The B-cell lymphoma 6 (BCL6) gene is localized to 3q27. Rearrangements of 3q27 may be seen in case diffuse large B-cell lymphoma (30-40%) and follicular lymphoma (5-15%). Structural rearrangements include translocations and microdeletions, with about one-half of the translocations involving the immunoglobulin genes at 14q32, 2p12 and 22q13. The remaining translocations involve 3q27 with a wide variety of other chromosome partners.
FISH can detect this rearrangement in either interphase or metaphase cells.