Translocation t (8;21) associated with marked granulocytic hyperplasia.
A 16-year-old boy with leukemia had a marked leucocytosis (165 x 10(9)/L) at presentation. The large number of neutrophils, myelocytes, and metamyelocytes and negative leucocyte alkaline phosphatase reaction raised the possibility of chronic myeloid leukemia. Cytogenetic analysis showed a deletion of chromosome 7, a t (8;21), a missing Y chromosome, and, in some cells, duplication of the der(21). The Philadelphia chromosome was not detected, nor was the breakpoint cluster region of chromosome 22 found to be rearranged. Myeloid leukemia with t (8;21) can therefore be associated with a greater degree of granulocytic hyperplasia than has so far been apparent, and cytogenetic analysis in this case has been crucial in distinguishing leukemia types.
Kohli
M
M
Department of Child Health, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom.
Daly
H
H
Davison
E V
EV
Kernahan
J
J
Reid
M M
MM
D000293:Adolescent; D002891:Chromosomes, Human, Pair 21; D002898:Chromosomes, Human, Pair 8; D003937:Diagnosis, Differential; D006098:Granulocytes / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia; D007621:Karyotyping; D007951:Leukemia, Myeloid / Q000235:genetics* / Q000473:pathology; D008297:Male; D014178:Translocation, Genetic