Simultaneous occurrence of biphenotypic T cell/myeloid lesions involving t(12;13)(p13;q14) in a pediatric patient.
This paper chronicles a 2-year-old girl who presented with acute leukemia/lymphoma syndrome of the T cell immunophenotype. At this time, the cytogenetic analysis of her bone marrow cells showed a reciprocal translocation between the short arm of chromosome 12 and the long arm of chromosome 13, t(12;13)(p13;q14). The immunophenotyping of bone marrow blast cells by flow cytometry revealed a population of cells positive for CD56, CD117, CD45, partial CD33, partial HLA-DR, CD13, CD7, CD2 and CD5. Therefore, a diagnosis of acute leukemia with a mixed T cell/myeloid phenotype was made. The patient had a poor response to classic T cell acute lymphocytic leukemia/lymphoma therapy; thus, her treatment was changed to a myeloid leukemia protocol, which produced a good response. She underwent a successful cord blood transplantation from an unrelated HLA partially matched donor. The coexistence of these two phenotypes prompts questions about the existence of clonal instability, which might influence the choice of therapy. The rarity of the t(12;13)(p13;q14) and the coexistence of T cell/myeloid markers suggest a nonrandom association. To the best of our knowledge, this is the first reported case in which a cell clone bearing a t(12;13)(p13;q14) translocation in a mixed T cell/myeloid lesion was detected.
Instituto de Tratamento do Câncer Infantil, University of São Paulo, Brazil.
Claudio
C
Carneiro Borba
Maria
M
de Lourdes Chauffaille
Sabri Saeed
SS
Sanabani
Juliana
J
Folloni Fernandes
Cristina
C
Aiko Kumeda
Elvira Deolinda
ED
Rodrigues Pereira Velloso
Katia
K
Jarandilha dos Santos
Marcia
M
Puato Vieira Pupim
Nelson
N
Hamerschlak
Vicente
V
Odone Filho
Israel
I
Bendit
D000208:Acute Disease; D015703:Antigens, CD / Q000032:analysis; D002675:Child, Preschool; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D005260:Female; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D007951:Leukemia, Myeloid / Q000175:diagnosis* / Q000188:drug therapy; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics*; D050783:Proto-Oncogene Proteins c-ets / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics; D014178:Translocation, Genetic; D000097764:ETS Translocation Variant 6 Protein
D015703:Antigens, CD; D006684:HLA-DR Antigens; D050783:Proto-Oncogene Proteins c-ets; D011948:Receptors, Antigen, T-Cell; D012097:Repressor Proteins; D000097764:ETS Translocation Variant 6 Protein