A case of near-triploidy in myelodysplastic syndrome with del(5q) combined with del(1p) and del(13q)

Abstract

Numerical and structural chromosomal abnormalities are common in hematological malignancies. Near-triploidy (58-80 chromosomes) is a numerical abnormality observed in 3% of adult cases of acute lymphoblastic leukemia. Near-triploidy is rare in myeloid lineage hematologic malignancies and compared to near-triploidy in lymphoid malignancies, near-triploidy in myeloid malignancies is associated with poor outcomes. Few studies on near-triploidy in myelodysplastic syndrome (MDS) have been reported, and the clinicopathologic significance of this condition is still unclear. Here, we report a novel case of MDS with near-triploidy and multiple structural chromosomal abnormalities: del(5q) combined with del(1p) and del(13q). These abnormalities were detected by cytogenetic analysis with array comparative genomic hybridization (CGH). Our results suggest that array CGH can be a useful tool for detecting chromosomal abnormalities in patients with MDS.

Keywords: Array CGH; Myelodysplastic syndrome; Near-triploidy.

Fig. 1

Bone marrow examination showed moderate dyserythropoiesis (A) and dysmegakaryopoiesis (B). Multi nucleation, nuclear budding erythroids, and unconnected nuclei megakaryocytes are marked with arrow (Wright-Giemsa stain, ×1,000).

Fig. 2

(A) A representative G-banded karyotype showing massive hyperdiploidy with del(1p), del(5q), and del(13q). Chromosome numbers are listed in green, and extra chromosomes are marked with arrows. (B) Whole genomic plot of the array CGH results showing additional copy gains in chromosomes 9 and 16. The pink dots represent the patient-to-control fluorescence intensity ratio, while the blue dots show dye-reversed control-to-patient fluorescence ratios. Array CGH revealed cryptic aberrations, mostly copy losses of 2.23-574.67 kb on 1q, 3p, 5q, and 7q. However, trisomies, tetrasomies, or pentasomies were not differentiated solely on the basis of array findings, and copy gains on 10q and 22q and copy losses on 18q identified by karyotypic analysis were not observed with array CGH. See the results section for more detailed array interpretation. Abbreviation: CGH, comparative genomic hybridization.