Lymph node blast crisis in chronic myeloid leukemia mimicking T-immunoblastic lymphoma
Leone, G.; La Rocca, L.M.; Teofili, L.; De Candia, E.; Landolfi, R.; Sica, S.; Zini, G.; Zollino, M.; Tabilio, A.
Haematologica 77(4): 311-314
1992
ISSN/ISBN: 0390-6078 PMID: 1427440 Document Number: 395387
Background: Chronic myeloid leukemia arises from a somatic mutation in a pluripotent stem cell. It generally terminates with a blastic crisis (BC). One third of BC are lymphoid, and most have a pre-B phenotype. Few cases of T-lymphoid BC have been reported. Here we describe a lymph node blast crisis mimicking T-immunoblastic lymphoma. Methods: Bone marrow and lymph nodes were histologically examined by standard methods and by an immunoperoxidase technique. Cytogenetic studies were also performed on lymph node and blood cells. Analysis of T-cell receptor genes and BCR rearrangements were preformed on DNA extracted from both frozen bone marrow and lymph-node cells. Results: Lymph-node histology showed an infiltration by large lymphoid blasts, consistent with a diagnosis of immunoblastic lymphoma. Blast cells were CD2, CD7, TDT positive, and negative for myeloid and mature lymphoid antigens. The Ph1 chromosome was found in both bone marrow and lymph-node cells. BCR rearrangement was found in the DNA from both bone marrow and lumph-node cells. TCR genes were not rearranged. Discussion: The present study provides strong evidence that the lymph-node blast crisis of CML can assume the morphological appearance of immunoblastic lymphoma and may retain the immunological phenotype and genetic features of early T cells with BCR rearrangements.