POLYMERASE CHAIN-REACTION ANALYSIS OF T-CELL RECEPTOR-GAMMA GENE REARRANGEMENTS IN CUTANEOUS B-CELL LYMPHOMAS

PCR analyses of T-cell receptor (TCR) gamma gene rearrangements in B-l ymphoid neoplasms have shown lineage infidelity and double rearrangeme nts involving both immunoglobulin heavy chain (IgH) and TCR gamma gene s. In order to investigate if this event is also a feature of cutaneou s B-cell malignancies, we tested for clonal TCR gamma rearrangements a panel of immunophenotypically and genotypically well characterized cu taneous B cell lymphomas (CBCL). Fifteen samples of frozen CBCL biopsi es were selected for the study. Diagnoses were established by routine histology and immunohistochemistry. Each of these cases displayed clon al IgH gene rearrangement. Polymerase chain reaction (PCR) analysis of the TCR gamma rearrangements followed by high-resolution polyacrylami de gel electrophoresis was utilized for detection of clonal TCR gamma rearrangements. In our investigation, none of the cases of CBCL invest igated by PCR showed the presence of clonal TCR gamma gene rearrangeme nts. These data indicate that double rearrangements involving both IgH and TCR gamma genes are not a feature of CBCL and confirm the B cell lineage specificity of this group of cutaneous lymphoid neoplasms.