BACKGROUND
The clonality of lymphoid infiltrates determined by polymerase chain reaction (PCR) for immunoglobulin heavy chain (IgH) or T cell receptor (TCR) genes is not only useful in confirming the diagnosis of malignant lymphoma but also in establishing the lineage of a clonal lymphoid proliferation. We analyzed the efficiency of PCR analyses for IgH and TCRgenes that have been routinely applied for the diagnosis of malignant lymphoma in our laboratory.
METHODS
Paraffin sections of 200 cases were analyzed by seminested PCR. Primers were FRIIIA-LJH/VLJH consensus primer for IgH gene and V-J consensus primer for TCR gene.
The cases showing negative results by PCR for TCR gene were further analyzed by multiplex V family primers with heteroduplex analysis.
RESULTS
PCR approach for IgH gene allowed detection of clonality in 100% of cases with false positive rate of 0.3% and false negative rate of 0%. The combination of PCR for TCR consensus primers with multiplex V family primers allowed detection of clonality in 91% of cases with false positive rate of 0.6% and false negative rate of 10.3%.
CONCLUSIONS
Combined analysis of IgH and TCR gene rearragnements by the PCR technique followed by heteroduplex analysis can be a useful diagnostic adjunct to determine the clonality of various lymphoproliferative diseases with high sensitivity. But clinical, morphological and immunophenotypical correlation should be considered to reach the final diagnosis due to a few false positive cases.