Cytogenetic evolution correlates with poor prognosis in myelodysplastic syndrome

Integrated analysis of genotype and phenotype reveals clonal evolution and cytogenetically driven disruption of myeloid cell maturation in myelodysplastic syndromes

BACKGROUND

Myelodysplastic syndromes (MDS) are a heterogenous collection of clonal bone marrow diseases characterized by cytopenias, abnormal karyotypes, molecular abnormalities, and dysplasia by flow cytometry and/or morphology. The progression of MDS to severe cytopenias and/or overt leukemia is associated with the accumulation of additional cytogenetic abnormalities, suggesting clonal evolution. The impact of these accumulated abnormalities on myeloid maturation and the severity of the disease is poorly understood.

METHODS

Bone marrow specimens from 16 patients with cytogenetic abnormalities were flow cytometrically sorted into three myeloid populations: progenitors, immature myeloid cells, and mature myeloid cells. Fluorescence in situ hybridization analysis was performed on each to determine the distribution of chromosomal abnormalities during myeloid maturation.

RESULTS

Our findings revealed three distinct distributions of cytogenetic abnormalities across myeloid maturation, each of which corresponded to specific cytogenetic abnormalities. Group 1 had continuous distribution across all maturational stages and contained patients with a single cytogenetic aberration associated with good-to-intermediate prognosis; Group 2 had accumulation of abnormalities in immature cells and contained patients with high-risk monosomy 7; and Group 3 had abnormalities defining the founding clone equally distributed across maturational stages while subclonal abnormalities were enriched in progenitor cells and contained patients with multiple, non-monosomy 7, abnormalities with evidence of clonal evolution.

CONCLUSIONS

Our findings demonstrate that low-risk abnormalities (e.g., del(20q) and trisomy 8) occurring in the founding clone display a markedly different disease etiology, with respect to myeloid maturation, than monosomy 7 or abnormalities acquired in subclones, which result in a disruption of myeloid cell maturation in MDS.

Cytogenetic peripheral blood monitoring in azacitidine treated patients with high-risk MDS/sAML: A monocentric real-world experience

In this single center retrospective analysis 76 patients with high-risk (HR) myelodysplastic syndrome (MDS) treated with azacitidine (AZA) were reviewed for response, especially cytogenetic response (cyR) using repeated chromosome banding analyses (CBA) of bone marrow (bm) metaphases and frequent sequential Fluorescence-in-situ Hybridization (FISH) analyses of immunomagnetically enriched CD34 + circulating peripheral blood cells (CD34 +pb-FISH). In total, 526 CD34 +pb-FISH analyses and 236 CBA were examined. Median observation time was 8.45 months, median number of AZA cycles applied was 8, median overall survival (OS) was 14.9 months, 42.1 % of patients responded to therapy according to IWG criteria: 5 complete response (CR), 0 partial response (PR), 12 bmCR, 15 stable disease with hematologic improvement (HI). HI was reached in 36.8 % of patients, 31.5 % became transfusion-independent. By CBA or CD34 +pb-FISH 20.4 % and 31.6 % of patients showed cyR, respectively. HI rate was significantly higher in cytogenetic responders than in non-responders, but there was no impact on OS or leukemia-free-survival. Cytogenetic responders showed significantly better OS than non-responders. Patients with ≥ 6 AZA cycles had significantly better OS than patients with < 6 cycles applied. Karyotype evolution (KE) as a manifestation of cytogenetic progression was diagnosed in 29.5 % and 17.1 % of patients by CBA and CD34 +pb-FISH, respectively. KE was associated with significantly poorer OS and leukemia-free-survival.

Cryptic aberrations may allow more accurate prognostic classification of patients with myelodysplastic syndromes and clonal evolution

The karyotype of bone-marrow cells at the time of diagnosis is one of the most important prognostic factors in patients with myelodysplastic syndromes (MDS). In some cases, the acquisition of additional genetic aberrations (clonal evolution [CE]) associated with clinical progression may occur during the disease. We analyzed a cohort of 469 MDS patients using a combination of molecular cytogenomic methods to identify cryptic aberrations and to assess their potential role in CE. We confirmed CE in 36 (8%) patients. The analysis of bone-marrow samples with a combination of cytogenomic methods at diagnosis and after CE identified 214 chromosomal aberrations. The early genetic changes in the diagnostic samples were frequently MDS specific (17 MDS-specific/57 early changes). Most progression-related aberrations identified after CE were not MDS specific (131 non-MDS-specific/155 progression-related changes). Copy number neutral loss of heterozygosity (CN-LOH) was detected in 19% of patients. MDS-specific CN-LOH (4q, 17p) was identified in three patients, and probably pathogenic homozygous mutations were found in TET2 (4q24) and TP53 (17p13.1) genes. We observed a statistically significant difference in overall survival (OS) between the groups of patients divided according to their diagnostic cytogenomic findings, with worse OS in the group with complex karyotypes (P = .021). A combination of cytogenomic methods allowed us to detect many cryptic genomic changes and identify genes and genomic regions that may represent therapeutic targets in patients with progressive MDS.

3D Telomere Structure Analysis to DetectGenomic Instability and Cytogenetic Evolutionin Myelodysplastic Syndromes

The disease course of myelodysplastic syndromes (MDS) features chromosome instability and clonal evolution, leading to the sequential acquisition of novel cytogenetic aberrations and the accumulation of these abnormalities in the bone marrow. Although clonal cytogenetic abnormalities can be detected by conventional cytogenetics in 50% of patients with MDS, such distinguishing patterns are lacking in the other 50%. Despite the increase in the prognostic value of some biomarkers, none of them is specific and able to discriminate between stable and unstable patients that subsequently progress to acute myeloid leukemia. This pilot study aimed to investigate the potential use of the 3D telomere profiling to detect genomic instability in MDS patients with or without clonal cytogenetic evolution. The comparison between different time points in patients with cytogenetic changes showed that in the CD34+ MDS cells, there was a significant decrease in the total number of telomeric signals, the average intensity of signals and the total intensity of telomeres. By contrast, the number of aggregates increased during cytogenetic evolution (p < 0.001). This pattern was observed only for MDS patients with cytogenetic evolution but was absent in patients without cytogenetic changes. In conclusion, we demonstrated that the 3D nuclear telomere organization was significantly altered during the MDS disease course, and may have contributed to cytogenetic clonal evolution.

Detailed analysis of clonal evolution and cytogenetic evolution patterns in patients with myelodysplastic syndromes (MDS) and related myeloid disorders

Clonal cytogenetic evolution (CE) (i.e., acquisition of new chromosomal aberrations over time) is relevant for the progression of myelodysplastic syndromes (MDS). We performed detailed analysis of CE in 729 patients with MDS and related disorders. Patients with CE showed shorter survival (median OS 18.0 versus 53.9 months; P < 0.01), higher leukemic transformation rate (48.0% versus 21.4%; P < 0.01) and shorter intervals to leukemic transformation (P < 0.01). Two main CE patterns were detected: early versus late CE (median onset 5.3 versus 21.9 months; P < 0.01) with worse survival outcomes for early CE. In the case of CE, del (7q)/−7 (P = 0.020) and del (17p) (P = 0.002) were especially unfavorable. Extending the evolution patterns from Tricot et al. (1985) forming five subgroups, prognosis was best (median OS not reached) in patients with “transient clones/changing clone size”, whereas those with “CE at diagnosis” showed very poor outcomes (P < 0.01 for comparison of all). Detailed sequential cytogenetic analysis during follow-up improves prognostication in MDS patients and acknowledges the dynamic biology of the disease. Evidence, time-point, and patterns of cytogenetic clonal evolution should be included into future prognostic scoring systems for MDS.

The genetics of myelodysplastic syndrome: from clonal haematopoiesis to secondary leukaemia

Myelodysplastic syndrome (MDS) is a clonal disease that arises from the expansion of mutated haematopoietic stem cells. In a spectrum of myeloid disorders ranging from clonal haematopoiesis of indeterminate potential (CHIP) to secondary acute myeloid leukaemia (sAML), MDS is distinguished by the presence of peripheral blood cytopenias, dysplastic haematopoietic differentiation and the absence of features that define acute leukaemia. More than 50 recurrently mutated genes are involved in the pathogenesis of MDS, including genes that encode proteins involved in pre-mRNA splicing, epigenetic regulation and transcription. In this Review we discuss the molecular processes that lead to CHIP and further clonal evolution to MDS and sAML. We also highlight the ways in which these insights are shaping the clinical management of MDS, including classification schemata, prognostic scoring systems and therapeutic approaches.

Atg3 Overexpression Enhances Bortezomib-Induced Cell Death in SKM-1 Cell

Background

Myelodysplastic syndrome (MDS) is a group of heterogeneous hematopoietic stem cell malignancies with a high risk of transformation into acute myeloid leukemia (AML). Clonal evolutions are significantly associated with transformation to AML. According to a gene expression microarray, atg3 is downregulated in MDS patients progressing to leukemia, but less is known about the function of Atg3 in the survival and death of MSD/AML cells. Moreover, the role of autophagy as a result of bortezomib treatment is controversial. The current study was designed to investigate the function of Atg3 in SKM-1 cells and to study the effect of Atg3 on cell viability and cell death following bortezomib treatment.

Methods

Four leukemia cell lines (SKM-1, THP-1, NB4 and K562) and two healthy patients’ bone marrow cells were analyzed for Atg3 expression via qRT-PCR and Western blotting analysis. The role of Atg3 in SKM-1 cell survival and cell death was analyzed by CCK-8 assay, trypan blue exclusion assay, DAPI staining and Annexin V/PI dual staining with or without bortezomib treatment. Western blotting analysis was used to detect proteins in autophagic and caspase signaling pathways. Electron microscopy was used to observe ultrastructural changes after Atg3 overexpression.

Results

Downregulation of Atg3 expression was detected in four leukemia cell lines compared with healthy bone marrow cells. Atg3 mRNA was significantly decreased in MDS patients’ bone marrow cells. Overexpression of Atg3 in SKM-1 cells resulted in AKT-mTOR-dependent autophagy, a significant reduction in cell proliferation and increased cell death, which could be overcome by the autophagy inhibitor 3-MA. SKM-1 cells overexpressing Atg3 were hypersensitive to bortezomib treatment at different concentrations via autophagic cell death and enhanced sensitivity to apoptosis in the SKM-1 cell line. Following treatment with 3-MA, the sensitivity of Atg3-overexpressing cells to bortezomib treatment was reduced. Atg3 knockdown blocked cell growth inhibition and cell death induced by bortezomib.

Conclusion

Our preliminary study of Atg3 in the high-risk MDS cell line suggests that Atg3 might be possibly a critical regulator of autophagic cell death and a gene target for therapeutic interventions in MDS.

Monitoring of the Clonal Fraction by Fluorescence In Situ Hybridization in Myelodysplastic Syndrome: Comparison With International Working Group Treatment Response Criteria

CONTEXT

-At the initial diagnosis of myelodysplastic syndrome (MDS) and/or during follow-up, the evaluation of chromosomal abnormalities is based on standard G-banding, whereas the utility of fluorescence in situ hybridization (FISH) is still debated.

OBJECTIVES

-To investigate whether interphase fluorescence in situ hybridization (iFISH) clone size at initial diagnosis of MDS is correlated with survival and whether changes in clonal fraction by iFISH are concordant with the MDS International Working Group response criteria during follow-up.

DESIGN

-A tailored FISH panel (-5/5q-, -7/7q-, +8, -20/20q-, and +1/1q+), based on reported cytogenetic changes in Korean patients with MDS, was performed in 81 patients with MDS at initial diagnosis and in 28 patients during follow-up.

RESULTS

-During follow-up, absolute increases in the clone size by iFISH by 20% or more, with relative increases of 50% or more, compared with previous specimens, were associated with transformation to acute myeloid leukemia (P = .001 and P = .002, respectively). Of the 28 patients with abnormal iFISH results, 7 (25%) showed discordance between iFISH and MDS International Working Group responses. Concordance between clone size by G-banding and iFISH was higher in the refractory cytopenia with unilineage dysplasia/refractory cytopenia with multilineage dysplasia group during follow-up, whereas the group with refractory anemia with excess blasts showed higher correlation at initial diagnosis.

CONCLUSIONS

-We conclude that iFISH can provide additional prognostic information and can predict the response to therapy in MDS.

Myelodysplastic syndromes, version 2.2015

The NCCN Guidelines for Myelodysplastic Syndromes (MDS) comprise a heterogeneous group of myeloid disorders with a highly variable disease course that depends largely on risk factors. Risk evaluation is therefore a critical component of decision-making in the treatment of MDS. The development of newer treatments and the refinement of current treatment modalities are designed to improve patient outcomes and reduce side effects. These NCCN Guidelines Insights focus on the recent updates to the guidelines, which include the incorporation of a revised prognostic scoring system, addition of molecular abnormalities associated with MDS, and refinement of treatment options involving a discussion of cost of care.

Prognostic impact of acquisition of cytogenetic abnormalities during the course of chronic myelomonocytic leukemia

Karyotypic abnormalities are detected in 20-40% of chronic myelomonocytic leukemia (CMML) patients at initial diagnosis and have been shown to correlate with patients' outcome. The significance of acquisition of cytogenetic abnormalities (ACA) during the course of CMML, however, is largely unknown. In a cohort of 314 CMML patients, karyotypic abnormalities were detected in 106 (34%) patients at the time of diagnosis; and ACA were detected in 80 (25%) patients after a median interval of 17 months (range, 2-117 months). The most frequently observed ACA were a complex karyotype, followed by +21, -7/del(7q), del(20q), i(17q), and -17/del(17p). ACA appeared to occur more frequently in patients with a normal or lower risk karyotype. Progression to AML was seen in 44 of 80 (55%) patients with ACA versus 67 of 234 (29%) patients without ACA (P < 0.0001). Presence of ACA predicted an inferior leukemia-free survival (LFS) by univariate (P = 0.0435) and multivariate analysis (HR = 1.892, P = 0.006). While acquisition of a complex karyotype was positively correlated with AML progression (P = 0.0086), del(20q) was associated with a stable disease (P = 0.0198). We conclude that ACA occur in ∼20-30% of CMML patients during the course of disease, and are significantly associated with AML progression and a shorter LFS. Karyotypic abnormalities, either present at diagnosis or acquired during the course of disease, have prognostic implication in CMML patients.

Acute adrenal insufficiency as a first presentation of myelodysplastic syndrome and sigmoid colon adenocarcinoma: a case report

Acute adrenal failure due to bilateral adrenal haemorrhage is rare and may initially present with non-specific symptoms. It can rapidly progress into a life-threatening condition if not diagnosed promptly. Both traumatic and non-traumatic conditions have been implicated in the aetiology, with the latter been even rarer. We describe the case of a 57-year-old woman presenting with vomiting and epigastric pain and later developing fever and diarrhoea. The patient then deteriorated into shock and primary adrenal insufficiency was identified. A computed tomography scan noted bilateral adrenal haemorrhage. Further investigations showed a sigmoid colon adenocarcinoma and a myelodysplastic syndrome, with monosomy seven. Bilateral non-traumatic adrenal haemorrhage is an infrequent finding and investigating its aetiology can be challenging. In our patient, two simultaneous underlying diseases were identified. To the best of our knowledge, the combination of these two non-traumatic conditions as a cause of acute bilateral adrenal haemorrhage has not been previously reported.

The impact of category, cytopathology and cytogenetics on development and progression of clonal and malignant myeloid transformation in inherited bone marrow failure syndromes

Inherited bone marrow failure syndromes are a group of rare, heterogeneous genetic disorders with a risk of clonal and malignant myeloid transformation including clonal marrow cytogenetic abnormalities, myelodysplastic syndrome and acute myeloid leukemia. The clinical characteristics, risk classification, prognostic factors and outcome of clonal and malignant myeloid transformation associated with inherited bone marrow failure syndromes are largely unknown. The aims of this study were to determine the impact of category, cytopathology and cytogenetics, the three components of the "Category Cytology Cytogenetics" classification of pediatric myelodysplastic syndrome, on the outcome of clonal and malignant myeloid transformation associated with inherited bone marrow failure. We used data from the Canadian Inherited Marrow Failure Registry. Among 327 patients with inherited bone marrow failure syndrome enrolled in the registry, the estimated risk of clonal and malignant myeloid transformation by the age of 18 years was 37%. The risk of clonal and malignant myeloid transformation varied according to the type of inherited bone marrow failure syndrome but was highest in Fanconi anemia. The development of clonal and malignant myeloid transformation significantly affected overall survival. Mortality varied based on cytopathological group. The largest group of patients had refractory cytopenia. Clonal marrow cytogenetic abnormalities were identified in 87% of patients with clonal and malignant myeloid transformation, and different cytogenetic groups had different impacts on disease progression. We conclude that category, cytopathology and cytogenetics in cases of clonal and malignant myeloid transformation associated with inherited bone marrow failure syndromes have an important impact on outcome and that the classification of such cases should incorporate these factors.

Role of chromosomal aberrations in clonal diversity and progression of acute myeloid leukemia

Genetic abnormalities are a hallmark of cancer. Hereby, cytogenetic aberrations and small-scale abnormalities, such as single-nucleotide variations and insertion/deletion mutations, have emerged as two alternative modes of genetic diversification. Both mechanisms are at work in acute myeloid leukemia (AML), in which conventional karyotyping and molecular studies demonstrate that gene mutations occur predominantly in cytogenetically normal AML, whereas chromosomal changes are a driving force of development and progression of disease in aberrant karyotype AML. All steps of disease evolution in AML, ranging from the transformation of preleukemic clones into overt leukemia to the expansion and recurrence of malignant clones, are paralleled by clonal evolution at either the gene mutation or chromosome aberration level. Preleukemic conditions, such as Fanconi anemia and Bloom syndrome, demonstrate that the acquisition of chromosomal aberrations can contribute to leukemic transformation. Similar to what has been shown at the mutational level, expansion and recurrence of AML clones goes along with increasing genetic diversification. Hereby, cytogenetically more evolved subclones are at a proliferative advantage and outgrow ancestor clones or have evolved toward a more aggressive behavior with additional newly acquired aberrations as compared with the initial leukemic clone, respectively.

Detection of clonal evolution in hematopoietic malignancies by combining comparative genomic hybridization and single nucleotide polymorphism arrays

BACKGROUND

Array comparative genomic hybridization (aCGH) has become a powerful tool for analyzing hematopoietic neoplasms and identifying genome-wide copy number changes in a single assay. aCGH also has superior resolution compared with fluorescence in situ hybridization (FISH) or conventional cytogenetics. Integration of single nucleotide polymorphism (SNP) probes with microarray analysis allows additional identification of acquired uniparental disomy, a copy neutral aberration with known potential to contribute to tumor pathogenesis. However, a limitation of microarray analysis has been the inability to detect clonal heterogeneity in a sample.

METHODS

This study comprised 16 samples (acute myeloid leukemia, myelodysplastic syndrome, chronic lymphocytic leukemia, plasma cell neoplasm) with complex cytogenetic features and evidence of clonal evolution. We used an integrated manual peak reassignment approach combining analysis of aCGH and SNP microarray data for characterization of subclonal abnormalities. We compared array findings with results obtained from conventional cytogenetic and FISH studies.

RESULTS

Clonal heterogeneity was detected in 13 of 16 samples by microarray on the basis of log2 values. Use of the manual peak reassignment analysis approach improved resolution of the sample's clonal composition and genetic heterogeneity in 10 of 13 (77%) patients. Moreover, in 3 patients, clonal disease progression was revealed by array analysis that was not evident by cytogenetic or FISH studies.

CONCLUSIONS

Genetic abnormalities originating from separate clonal subpopulations can be identified and further characterized by combining aCGH and SNP hybridization results from 1 integrated microarray chip by use of the manual peak reassignment technique. Its clinical utility in comparison to conventional cytogenetic or FISH studies is demonstrated.

Cytogenetic as an important tool for diagnosis and prognosis for patients with hypocellular primary myelodysplastic syndrome

We analyzed cytogenetically 105 patients with hypocellular primary MDS and their clinical implications. The main chromosomal abnormalities found were del(5q)/−5, del(6q)/+6, del(7q)/−7, del(11q), and del(17p). Pediatric patients had a higher frequency of abnormal karyotypes compared with adult patients (P < 0,05). From our patients, 18% showed evolution of the disease. The chromosomal abnormalities presented in the diagnosis of patients who evolved to AML included numerical (−7, +8) and structural del(6q), del(7q), i(7q), t(7;9), i(9q), and del(11q) abnormalities and complex karyotypes. Although the frequency of evolution from hypocellular MDS to AML is low, our results suggest that some chromosomal alterations may play a critical role during this process. We applied the IPSS in our patients because this score system has been proved to be useful for predicting evolution of disease. When we considered the patients according to group 1 (intermediate-1) and group 2 (intermediate-2 and high risk), we showed that group 2 had a high association with respect to the frequency of abnormal karyotypes (P < 0,0001), evolution of disease (P < 0,0001), and mortality (P < 0,001). In fact, the cytogenetic analysis for patients with hypocellular primary MDS is an important tool for diagnosis, prognosis, in clinical decision-making and in follow-up.

The genetic basis and expanding role of molecular analysis in the diagnosis, prognosis, and therapeutic design for myelodysplastic syndromes

The myelodysplastic syndromes (MDS) are clonal hematopoietic stem cell disorders of ineffective hematopoiesis that characteristically demonstrate peripheral blood cytopenia, bone marrow hypercellularity, and morphologically defined dysplasia of one or more hematopoietic lineages. Classical metaphase cytogenetics and judicious use of fluorescence in situ hybridization play central roles in the contemporary diagnosis and classification of MDS. An abundance of recent molecular studies are beginning to delineate additional genetic and epigenetic aberrations associated with these disorders. These alterations affect diagnosis, prognosis, and therapy, and with this understanding classification systems are evolving from a primarily hematological and morphological basis toward a multifactorial appreciation that includes histomorphology, metaphase cytogenetics, and directed molecular studies. In the present health-care environment, it is critical to develop a cost-effective, efficient testing strategy that maximizes the diagnostic potential of even limited specimens. Here, we briefly review the classical genetic approach to MDS, outline exciting new advances in the molecular understanding of this heterogeneous group of hematological neoplasms, and discuss how these advances are driving the evolution of classification and prognostic systems. Rapidly growing understanding of the genetic basis of MDS holds much promise for testing, and here we provide a frame of reference for discussion of current testing protocols and for addressing testing modalities likely to enter clinical practice in the near future.

Acquisition of cytogenetic abnormalities in patients with IPSS defined lower-risk myelodysplastic syndrome is associated with poor prognosis and transformation to acute myelogenous leukemia

We hypothesized that the dynamic acquisition of cytogenetic abnormalities (ACA) during the follow up of myelodysplastic syndromes (MDS) could be associated with poor prognosis. We conducted a retrospective analysis of 365 patients with IPSS low or intermediate-1 risk MDS who had at least two consecutive cytogenetic analyses during the follow up. Acquisition of cytogenetic abnormalities was detected in 107 patients (29%). The most frequent alteration involved chromosome 7 in 21% of ACA cases. Median transformation-free and overall survival for patients with and without ACA were 13 vs. 52 months (P = 0.01) and 17 vs. 62 months (P = 0.01), respectively. By fitting ACA as a time-dependent covariate, multivariate Cox regression analysis showed that patients with ACA had increased risk of transformation (HR = 1.40; P = 0.03) or death (HR = 1.45; P = 0.02). Notably, female patients with therapy-related MDS (t-MDS) had an increased risk of developing ACA (OR = 5.26; P < 0.0001), although subgroup analysis showed that prognostic impact of ACA was not evident in t-MDS. In conclusion, ACA occurs in close to one third of patients with IPSS defined lower risk MDS, more common among patients with t-MDS, but has a significant prognostic impact on de novo MDS.

Morphology, cytogenetics and classification of MDS

Myelodysplastic syndromes are heterogeneous bone marrow diseases with a variable pathogenetic background. Cytomorphological alterations in peripheral blood films as well as bone marrow aspirates and histological findings in trephine biopsies result from cytogenetic and molecular abnormalities, epigenetic dysregulation and immune dysfunction and are key elements for setting the diagnosis of MDS. Whereas diagnosis can be made quite easily in advanced MDS this is much more difficult in early MDS, especially in cases with cytopenias or dysplasias of uncertain significance (ICUS and IDUS). Recommendations, illustrated by case reports for a stepwise annealing to the final diagnosis and exclusion of differential diagnoses are given. Furthermore, the problem of correct counting and identification of blasts is covered and features defining dysplasia in all three cell lineages are recapitulated thoroughly. Histopathology is not mandatory but has a distinct diagnostic and prognostic value especially in cases with hypoplasia or fibrosis and when the TP53 mutational status is of relevance. In up to 70% of patients with MDS clonal chromosome abnormalities can be identified which have a high impact on setting the correct diagnosis and estimation of prognosis. Incidence, type, molecular background and clinical relevance of distinct anomalies as well as cytogenetic subgroups are presented in detail and the development of the new cytogenetic prognostic scoring system as part of the IPSS-R is explained. The value of FISH-Analysis as a complementary tool for chromosome analysis in MDS is demonstrated with special emphasis on the possibility to perform frequent cytogenetic monitoring by CD34-FISH examination of peripheral blood. Finally the evolution of MDS-classification systems from FAB to WHO with a critical discussion of their shortcomings like degree of dysplasia, blast thresholds, inclusion/exclusion of CMML, and the lack of dynamic information is presented.

5q- syndrome and multiple myeloma diagnosed simultaneously and successful treated with lenalidomide

A 72-year-old woman was diagnosed with 5q- myelodysplastic syndrome in the course of an indolent multiple myeloma (MM). Bone marrow (BM) cytogenetics disclosed two unrelated clones: 46,XX,del(5)(q13q33), and [47,X,-X,der(1;21)(q10;q10),-4,-4,+5,del(5)(q13q31),+7,der(7)t(1;7)(p34.2;p22),add(8)(p23),-13,+15,der(16) t(1;16)(q23;q12.2),+19,-21,+mar1,+mar2]. The last complex karyotype belonged to malignant plasma cells. FISH and SKY techniques demonstrated different 5q deletions. EGR1 gene (on 5q31) lost in 5q- syndrome remained in 5q- plasma cells. Biclonal evolution was noted: myeloid 5q- cells added a deletion 13q and plasma cells showed monosomy 13. Patient achieved complete cytogenetic response of 5q- syndrome with low-dose of lenalidomide, and a partial remission of MM with high-dose of lenalidomide/dexamethasone combination.

Cytogenetic follow-up by karyotyping and fluorescence in situ hybridization: implications for monitoring patients with myelodysplastic syndrome and deletion 5q treated with lenalidomide

In patients with low and intermediate risk myelodysplastic syndrome and deletion 5q (del(5q)) treated with lenalidomide, monitoring of cytogenetic response is mandatory, since patients without cytogenetic response have a significantly increased risk of progression. Therefore, we have reviewed cytogenetic data of 302 patients. Patients were analyzed by karyotyping and fluorescence in situ hybridization. In 85 patients, del(5q) was only detected by karyotyping. In 8 patients undergoing karyotypic evolution, the del(5q) and additional chromosomal aberrations were only detected by karyotyping. In 3 patients, del(5q) was only detected by fluorescence in situ hybridization, but not by karyotyping due to a low number of metaphases. Karyotyping was significantly more sensitive than fluorescence in situ hybridization in detecting the del(5q) clone. In conclusion, to optimize therapy control of myelodysplastic syndrome patients with del(5q) treated with lenalidomide and to identify cytogenetic non-response or progression as early as possible, fluorescence in situ hybridization alone is inadequate for evaluation. Karyotyping must be performed to optimally evaluate response.