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Polymerase chain reaction (PCR)-based detection of clonal T- and B-cells is widely used in the diagnosis of various lymphomas, including those of the skin. A large number of corresponding methods have been published. Recently, for the first time, standardized PCR protocols were developed in common by 14 European centers of lymphoma diagnosis and research (Biomed-2 protocols). Here, we have applied Biomed-2 immunoglobulin heavy chain (IgH)-PCR for clonality detection in primary cutaneous B-cell lymphoma (CBCL) and compared it with previously established methods. The DNA of 43 paraffin-embedded lesional skin biopsies of confirmed CBCL cases [27 follicle center cell lymphoma (FCCL), 11 marginal zone B-cell lymphoma/immunocytoma (MZL/IC) and five large CBCL of the lower leg (CBCL-LL)] were amplified by the Biomed-2 IgH-PCR protocols as well as using four other assays, priming also the three IgH framework regions (FR) 1–3. All PCR products were analysed by fluorescence fragment analysis. Twenty-nine of 43 (67%) CBCL samples (5/5, 100% of CBCL-LL; six of 11, 54.5% of IC/MZL; 18 of 27, 66.7% of FCCL) showed monoclonal B-cell presence complementary in all of the IgH-PCR. The three Biomed-2 PCR indicated together clonality in 24 of 43 samples (56%). Considering each method separately, the Biomed-2 FR3-PCR showed the highest rate of clonality detection (20 of 43, 47%). In conclusion, the Biomed-2 FR3-PCR is recommended for detecting B-cell clonality in archival skin samples of CBCL but should be completed by FR1- and/or FR2-PCR. [ABSTRACT FROM AUTHOR]

Detection of a clonal T cell receptor (TCR) gene rearrangement is used in the diagnosis of primary cutaneous T cell lymphomas (CTCL) whereas chromosomal aberrations serve as a diagnostic tool for leukaemias and nodal lymphomas. To what extent both approaches specify the same cell population remains unknown. We investigated the coincidence of TCR clonality with complex clonal chromosomal aberrations, indicating qualitative alteration of the affected cells, in 17 CTCL patients. Out of 41 skin, blood, and lymph node samples studied, 34 gave results in chromosome and TCR analyses. With 88%, most specimens revealed corresponding results by both techniques (27 of 34 clonal, three of 34 non-clonal). In two patients, analysis of micro-dissected cells demonstrated that neoplastic T cells bear both a dominant TCR rearrangement and a complex chromosomal aberration. The cutaneous clone was found in blood samples of 11 of 12 patients (including early stages), and investigation of follow-up skin and blood samples indicated persistence of the T cell clone in 11 of 14 cases. In conclusion, we show that dominant TCR clones and chromosomal clones converge in all stages of CTCL. These clones disseminate into blood and skin at early disease stages and persist despite therapy. The coexistence of a dominant TCR clone and a clonal chromosomal aberration can thus be used as a hallmark of malignancy. [ABSTRACT FROM AUTHOR]