A study of lymphoma of large granular lymphocytes with modern modalities: report of two cases and review of the literature.
Two cases of lymphoma of large granular lymphocytes are reported. The first case expressed natural killer (NK) cell, some T-cell (CD 2, CD 5, CD 8), and HLA-DR antigens, but was negative for other T-cell (CD 3, CD 4, CD 7), T-cell receptor (TCR), B-cell, and myeloid antigens. Germline configuration was demonstrated for TCR, and immunoglobulin heavy and light chain genes. The second case expressed NK cell, some T-cell (CD 3, CD 7, CD 8), and TCR antigens, but was negative for other T-cell (CD 4, CD 5), B-cell, myeloid, and HLA-DR antigens. Rearrangement of TCR alpha and beta chains were detected. Thus, the findings of case 1 were consistent with true NK cell lineage and case 2 with NK-like T-cell lineage. Our report underscores the heterogeneity of this newly recognized lymphoma, which nevertheless carries a consistently poor prognosis and is probably more prevalent in the Asian population. This study also provides information concerning immunophenotypes of cellular infiltrates in internal organs and cytogenetic abnormalities in this lymphoma; neither has been reported frequently in the literature. The importance of detecting cytoplasmic granules in tissue imprints or electron micrographs for differentiating other T-cell lymphomas is emphasized, and the classification of large granular lymphoproliferative disorders is discussed.