Gain of an Isochromosome 5p: a Rare Recurrent Abnormality in Acute Myeloid Leukemia

Abstract

Chromosomal abnormalities characterize the biological behavior of acute myeloid leukemia (AML), also facilitating the identification of genes responsible for its development and/or progression. Isochromosome 5p, i(5p), represents a rare chromosomal abnormality described, to date, in only a few AML cases. In almost all the cases reported, the i(5p) was accompanied by other abnormalities. Here, a new case of AML, evolved from a myelodysplastic syndrome (MDS) with a clonal trisomy 8, is reported. The case presented the following karyotype: 46, XY [ 15 ] / 47, XY, + 8[ 4 ] / 47, XY, + i ( 5 ) ( p 10 ) [ 3 ] / 48,XY, +i(5)(p10)+8[3]. To our knowledge, this is the first reported case of AML to present a clone with an isolated i(5p). The cytogenetic findings supported the hypothesis that i(5p) may represent a primary abnormality, which characterizes a small subset of AML cases.