Rare Cytogenetic Abnormalities in Myelodysplastic Syndromes

Abstract

The karyotype represents one of the main cornerstones for the International Prognostic Scoring System (IPSS) and the revised IPSS-R (IPSS-R) that are most widely used for prognostication in patients with myelodysplastic syndromes (MDS). The most frequent cytogenetic abnormalities in MDS, i.e. del(5q), -7/del(7q), +8, complex karyotypes, or −Y have been extensively explored for their prognostic impact. The IPSS-R also considers some less frequent abnormalities such as del(11q), isochromosome 17, +19, or 3q abnormalities. However, more than 600 different cytogenetic categories had been identified in a previous MDS study. This review aims to focus interest on selected rare cytogenetic abnormalities in patients with MDS. Examples are numerical gains of the chromosomes 11 (indicating rapid progression), of chromosome 14 or 14q (prognostically intermediate to favorable), -X (in females, with an intermediate prognosis), or numerical abnormalities of chromosome 21. Structural abnormalities are also considered, e.g. del(13q) that is associated with bone marrow failure syndromes and favorable response to immunosuppressive therapy. These and other rare cytogenetic abnormalities should be integrated into existing prognostication systems such as the IPSS-R. However, due to the very low number of cases, this is clearly dependent on international collaboration. Hopefully, this article will help to inaugurate this process.

Myelodysplastic Syndromes in Pakistani Population-Analysis of 52 Cases and their Outcome on Best Available Treatment Options

“…Isolated deletion 5q was seen only in a single female patient who presented as refractory anemia. Numerical gain of chromosome 11 a rare cytogenetic finding in MDS is also observed in one case [11]. Other cytogenetic findings are mentioned in Table 5.…”

“…Median progression free survival of all followed up cases is 1.5 months for very high risk, 6 months for high risk, 13 (Figure 2). Disease specific treatment was chosen by only 26 (50%) patients due to availability of resources out of which 1 (3.8%) was very low risk, 9 (34.6%) were low risk, 11 …”

Primary myelodysplastic syndrome with two rare recurrent chromosome abnormalities [t(3q26.2;q22) and trisomy 13] associated with resistance to chemotherapy and hematopoietic stem cell transplantation

“…Moreover, according to multicentric cytogenetic studies, trisomy 13 was observed in 0.2% patients, detectable as an single aberration, or combined with an additional abnormality [20]. A sufficient gender imbalance was reported for this condition (21 males of 27 cases).…”

Prognostic Markers of Myelodysplastic Syndromes

“…Translocation 11q23/MLL is another very rare occurrence in primary MDS, with the overall survival being about 26 months and the risk to develop acute leukemia being up to 40% within a one-year interval and up to 92% within a five-year period. Loss of one X chromosome in women is a rare abnormality in MDS and AML: it occurs in 0.2–0.3% of cases and in up to 1.5% of patients who combine these conditions with other abnormalities and is characterized by a median overall survival of ~6 months [ 89 ]. The presence of translocation 1q in three patients originally diagnosed with MDS, which later evolved to AML, has been reported [ 90 ].…”