LYMPHOMA WITH MULTI GENE REARRANGEMENT ON THE LEVEL OF IMMUNOGLOBULINHEAVY-CHAIN, LIGHT-CHAINS, AND T-CELL RECEPTOR-BETA CHAIN

A unique case with diffuse mixed malignant lymphoma was investigated f or gene rearrangement on the level of T-cell receptor (TCR), heavy cha in immunoglobulin (Ig), and both light chains, Cell phenotype was exam ined with immunofluorescence techniques using antibodies against surfa ce immunoglobulins (Slg) and the kappa and lambda light chains. Monocl onal antibodies were used against CD3, CD4, CD5, CD8, CD10, CD19, CD22 , HLA-DR, and tdT. Gene rearrangement analysis for monoclonality deter mination was carried out with restricted DNA (EcoR I and Hind III) hyb ridized with one of the following P-32-labelled probes: T-cell recepto r (TCR beta), immunoglobulin heavy chain (JH), k light chain, and lamb da light chain, Phenotyping of the cell population from the excised ly mph node (LN) revealed the presence of 66% B-cells and 35% T-cells. Mo st of the B cells (94%) expressed mu heavy chain only. Expression of b oth light chains was negligible (k = 7% and lambda = 2%). Gene rearran gement, which indicates monoclonality, was positive on the level of TC R, Ig heavy chain, and both light chains, The data obtained suggests a neoplastic transforming event in lymphoid stem cells, which preceded the subsequent differentiation process into either B or T lymphoma. (C ) 1997 Wiley-Liss, Inc.