A new variant t(6;15;17)(q25;q22;q21) in acute promyelocytic leukemia: fluorescence in situ hybridization confirmation.
Acute promyelocytic leukemia (APL) is characterized by the t(15;17)(q22;q21), which results in the fusion of the promyelocytic leukemia (PML) gene at 15q22 with the retinoic acid alpha-receptor (RARalpha) at 17q21. The 2 chimeric genes PML/RARalpha and RARalpha/PML are thought to play a role in leukemogenesis. We report a case of APL in a patient carrying an apparently complex variant translocation identified as t(6;15;17) by R-banding and whole chromosome 15 and 17 painting. However, FISH analysis with a PML/RARalpha dual-color kit showed a more complex translocation, resulting presumably from a two-step rearrangement, with PML-RARalpha fusion gene located as expected on the der(15) but the residual 5'-RARalpha signal located on the der(6). The patient achieved complete remission with all-trans retinoic acid treatment associated with chemotherapy. This case illustrates the usefulness of combined cytogenetics, FISH, and molecular biology to evidence the PML/RARalpha fusion gene in complex cases.
Eclache
Virginie
V
Laboratoire d'Hématologie, Hôpital Jean Verdier, Bondy, France. eclache@avc.ap-hop-paris.fr
Viguie
Franck
F
Frocrain
Claudie
C
Cassinat
Bruno
B
Chomienne
Christine
C
Cymbalista
Florence
F
Fenaux
Pierre
P
D002871:Chromosome Banding; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D014178:Translocation, Genetic
D009363:Neoplasm Proteins; D015514:Oncogene Proteins, Fusion; C093476:promyelocytic leukemia-retinoic acid receptor alpha fusion oncoprotein