Successive transformation of chronic myelomonocytic leukaemia into acute myeloblastic then lymphoblastic leukaemia, both with minor-bcr rearrangement.
We report a case of chronic myelomonocytic leukaemia (CMML), which transformed first into acute myeloblastic leukaemia (AML) and then into acute lymphoblastic leukaemia (ALL). In the AML and ALL phases, chromosome analysis showed a classic Philadelphia chromosome (Ph) t(9:22)(q34:q11). Molecular studies showed breakpoint cluster region rearrangement between exons e1 and a2 compatible with a p190(bcr/abl) breakpoint as observed in Ph-positive lymphoblastic acute leukaemia. The minor (m-bcr) rearrangement was also detected during complete remission. This observation supports a multistep pathogenesis of leukaemias, and that the p190(bcr/abl) breakpoint may influence the course of the disease.
Dautel
M M
MM
Laboratoire d'Hématologie, CDTS Angers, France.
François
S
S
Bertheas
M F
MF
Baranger
L
L
Gardais
J
J
Boasson
M
M
Ifrah
N
N
Blanchet
O
O
D000368:Aged; D002471:Cell Transformation, Neoplastic; D002892:Chromosomes, Human, Pair 22; D002899:Chromosomes, Human, Pair 9; D018450:Disease Progression; D016044:Fusion Proteins, bcr-abl / Q000235:genetics; D015321:Gene Rearrangement; D006801:Humans; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000235:genetics / Q000473:pathology*; D015477:Leukemia, Myelomonocytic, Chronic / Q000235:genetics / Q000473:pathology*; D008297:Male; D016133:Polymerase Chain Reaction; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics / Q000473:pathology*; D014178:Translocation, Genetic
D016044:Fusion Proteins, bcr-abl