T-lymphoid extramedullary (lymphadenopathic) blast crisis in CML.
T-cells are only rarely involved in chronic myeloid leukemia. We report an unusual case of T-lymphoid extramedullary (lymphadenopathic) blast crisis in a 66-year-old patient with Philadelphia positive chronic myeloid leukemia. The lymph node morphological picture resembled that of a peripheral T-cell lymphoma. Immunohistochemical stainings showed most lymph node blasts to have T-phenotype (positivity for CD-2, CD-3 and CD-5). Flow cytometric phenotyping confirmed T-phenotype, with positivity for CD-7, CD-38 and TdT. Cytogenetic analysis of lymph node cells revealed Philadelphia chromosome with an additional chromosomal abnormality (add(6p)). The BCR-gene rearrangement in the lymph node blasts was identical to that in the bone marrow. This case adds to the growing evidence that CML may be a disorder of the common stem cell from which T-, B- and myeloid progenitors originate.
Van Dorpe
J
J
A.Z. Sint-Jan, Brugge.
Van Damme
S
S
Jacobs
V
V
Van den Berghe
H
H
Criel
A
A
Michielssen
P
P
Louwagie
A
A
D000368:Aged; D001752:Blast Crisis; D005434:Flow Cytometry; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000473:pathology*; D008297:Male; D010641:Phenotype; D013601:T-Lymphocytes