Hybrid lymphoid blast crisis of chronic myeloid leukemia with both immunoglobulin and T-cell receptor gene rearrangements.
A case of Ph1+ chronic myeloid leukemia in blast crisis (CML-BC) is reported, in which the periodic acid Schiff and myeloperoxidase negative blasts displayed high terminal deoxynucleotidyl activity and coexpressed both B- (CD19, CD10, and CD24) and T- (CD7) lymphoid markers. In line with the immunophenotype, DNA analysis revealed a rearranged configuration of both the immunoglobulin and T-cell receptor (beta, gamma, and delta) genes. In spite of this dual B/T phenotype and genotype, the negativity of CyCD3 favors the suggestion that the target of the neoplastic event is an early B cell, with a cross lineage involvement of the putative common recombinase. However, taking into account that a normal counterpart of a biphenotypic B/T ALL has been recognized, it could be hypothesized that the leukemic transformation may have involved an oligopotent B/T lymphoid precursor. This case confirms the lineage heterogeneity of CML-BC and suggests that DNA analyses coupled to extensive immunophenotyping may allow further insight for a more precise recognition of both normal and leukemic ontogenesis.
Morabito
F
F
Divisione di Ematologia Ospedali Ospedali Riuniti Reggio Calabria, University of Torino, Italy.
Callea
V
V
Oliva
B
B
di Celle
P F
PF
Carbone
A
A
Nobile
F
F
Foa
R
R
D000328:Adult; D000943:Antigens, Differentiation / Q000032:analysis; D001752:Blast Crisis / Q000235:genetics / Q000473:pathology*; D004253:DNA Nucleotidylexotransferase / Q000378:metabolism; D004273:DNA, Neoplasm / Q000032:analysis; D015321:Gene Rearrangement / Q000235:genetics*; D015329:Gene Rearrangement, T-Lymphocyte / Q000235:genetics*; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics*; D016130:Immunophenotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D008297:Male
D000943:Antigens, Differentiation; D004273:DNA, Neoplasm; D007136:Immunoglobulins; D004253:DNA Nucleotidylexotransferase