5q– as the only cytogenetic abnormality in myelodysplastic syndrome with blast excess

Cytogenetic studies are required for the diagnosis of myelodysplastic neoplasms (MDS) because the World Health Organization 2022 classification divides MDS into a group with defined genetic abnormalities and MDS that are defined morphologically. Additionally, this paper modifies the terminology to clarify the distinction between MDS with low (5 % in bone marrow) and increased blast cell counts (5–9 % for MDS with blast excess 1 and 10–19 % for MDS with blast excess 2).This article describes the clinical observation of a patient with blast excess MDS and isolated 5q deletion.