Detection of immunoglobulin heavy chain and T cell receptor gene rearrangement in lymph node aspirates with PCR: Diagnostic significances for lymphoproliferative disorders

Lymph node aspirets of 17 cases with enlarged superficial or visceral lymph nodes were detected for immunoglobulin heavy chain gene rearrangement (IgHRA) and T cell receptor gene rearrangement (TCRγRA) by polymerase chain reaction (PCR) . Combining with c clinical data, pathologic diagnosis and immunophenotypy , we analyzed the results as follows: 5 cases of nonlymphoid cancers and 3 cases of reactive lymphadepathy did not present two kinds of clone gene rearrangement. 5 out of 7 cases of NHL showed clone gene rearrangements (IgH 3 cases, TCRγ 2 cases) , two kinds of monoclonal band (100~120bp for IgHRA and 170~230bp for TCRγRA) were observed after electrophoresis of amplified DNA products. One case whose clinical situation accorded with features of lymphoma was diagnosed as granulomatously mphadenitis by pathologist, but after gene rearrangement,clone TCRγRA was detected and a correct diagnosis as NHL was made. The significances of detecting two kinds of gene rearrangement for diagnosis and limitation in lymphoproliferative disorders were discussed.

Summary
Polymerase chain reaction (PCR) was used to detect immunoglobulin heavy chain (IgH) and T cell receptor gamma (TCRγ) gene rearrangement in puncture fluid cells of 17 cases of superficial or visceral enlargement of unknown etiology, combined with clinical, Pathological and immunophenotype analysis found that 5 cases of non-lymphoid carcinoma and 3 cases of reactive lymphoid proliferation had no above clonal gene rearrangement; 7 cases of non-Hodgkin's lymphoma (NHL), 3 cases showed clonal IgH gene rearrangement , 2 cases showed TCRγ gene rearrangement, and the PCR products showed monoclonal bands of 100-120 bp and 170-230 bp respectively after electrophoresis; 1 case was clinically consistent with NHL, and the pathological diagnosis was granulomatous inflammation but clonal TCRγ rearrangement occurred, and the diagnosis was revised It was NHL; 1 case was underdiagnosed due to too few samples. The author discusses the clinical application value and limitations of the above techniques.