Angioimmunoblastic lymphadenopathy with trisomy 3: the cells of the malignant clone are T cells.

A method involving simultaneous demonstration of the immunophenotype and the karyotype was applied to a case of angioimmunoblastic lymphadenopathy (AILD), in which the standard chromosome preparation revealed an aberrant clone with trisomy 3 and additional changes. The aberrant mitoses showed a positive reaction with the monoclonal T-cell antibody Leu 4 (CD3). This new method thus provides definite evidence that the malignant clone with trisomy 3, a characteristic finding in AILD, belongs to the T-cell population. Nevertheless, cytogenetically normal T cells were also found. Moreover, a cell from the same clone was found in the phytohemagglutinin-stimulated blood lymphocytes. This finding demonstrates that AILD may have a leukemic variant.