Angioimmunoblastic lymphadenopathy type of T-cell lymphoma and angioimmunoblastic lymphadenopathy: a clinicopathological and molecular biological study of 13 Chinese patients using polymerase chain reaction and paraffin-embedded tissues.

The morphological classification of angioimmunoblastic lymphadenopathy (AILD) or T-cell lymphoma of AILD-type (AILD-TCL) is still a subject of considerable difficulty and controversy. The aim of the current study was to examine the value of clinical, morphological, immunohistochemical variables in paraffin-embedded tissues in predicting the clonality of the respective lesion. Fifteen lymph node biopsies derived from 13 patients from Chengdu, China, were diagnosed as AILD or AILD-TCL and included in this study. The specimens were examined using a panel of monoclonal antibodies and a scoring system of morphological features. Clonality of the paraffin-embedded material was investigated using a novel polymerase chain reaction-technique to amplify rearranged T-cell receptor (TCR)-gamma sequences. Additional experiments were carried out to investigate the presence of clonal rearrangements of the immunoglobulin heavy chain (IgH) locus. We found clonal rearrangements of the TCR-gamma locus in 9 out of 15 lymph node biopsies. In 3 patients, the predominant cell clones carried clonal IgH and TCR-gamma rearrangements whereas 1 patient with polyclonal TCR-gamma pattern displayed IgH-monoclonality. The statistical evaluation of morphological and immunohistochemical data indicated that no single variable was able significantly to predict the clonality of the lesion. Furthermore, demonstrable clonality for the TCR-gamma or the IgH loci of a lesion did not correlate with a bad clinical course. Our data correlate with findings of other studies investigating AILD-TCL in Caucasian populations.