Clinical outcome of therapy-related acute myeloid leukemia patients. Real-life experience in a University Hospital and a Cancer Center in France.

BACKGROUND: t-AML occurs after a primary malignancy treatment and retains a poor prognosis. AIMS: To determine the impact of primary malignancies, therapeutic strategies, and prognostic factors on clinical outcomes of t-AML. RESULTS: A total of 112 adult patients were included in this study. Fifty-Five patients received intensive chemotherapy (IC), 33 non-IC, and 24 best supportive care. At t-AML diagnosis, 42% and 44% of patients presented an unfavorable karyotype and unfavorable 2010 ELN risk profile, respectively. Among treated patients (n = 88), 43 (49%) achieved complete remission: four out of 33 (12%) and 39 out of 55 (71%) in non-IC and IC groups, respectively. With a median follow-up of 5.5 months, the median overall survival (OS) and disease-free survival (DFS) for the whole population were 9 months and 6.3 months, respectively, and for the 88 treated patients 13.5 months and 8.2 months, respectively. Univariate analysis on OS and DFS showed a significant impact of high white blood cells (WBC) and blast counts at diagnosis, unfavorable karyotype and ELN classification. Multivariate analysis showed a negative impact of WBC count at diagnosis and a positive impact of chemotherapy on OS and DFS in the whole population. It also showed a negative impact of previous auto-HCT and high WBC count on OS and DFS and of IC on OS in treated patients which disappeared when we considered only confounding variables (age, previous cancers, marrow blasts, and 2010 ELN classification). In a pair-matched analysis comparing IC treated t-AML with de novo AML, there was no difference of OS and DFS between the two populations. CONCLUSION: We showed, in this study that t-AML patients with unfavorable features represented almost half of the population. Best outcomes obtained in patients receiving IC must be balanced by known confounding variables and should be improved by using new innovative agents and therapeutic strategies.

First-line second generation tyrosine kinase inhibitors in patients with newly diagnosed accelerated phase chronic myeloid leukemia.

Accelerated phase (AP) CML at onset and have poorer prognosis than CP-CML. We hypothesize that off-license use of second generation TKI (TKI2) as front-line therapy might counterbalance this poor prognosis, with limited toxicity. In "real-life" conditions, newly diagnosed patients meeting the ELN cytological criteria for AP-CML or harboring ACA and treated with first-line TKI2 were included in this retrospective multicenter observational study. We enrolled 69 patients [69.5 % male, median age 49.5 years, median follow-up 43.5 months], segregated into hematologic AP [HEM-AP (n = 32)] and cytogenetically defined AP [ACA-AP (n = 37)]. Hematologic parameters were worse in HEM-AP [spleen size (p = 0.014), PB basophils (p < .001), PB blasts (p < .001), PB blasts+promyelocytes (p < .001), low hemoglobin levels (p < .001)]. Dasatinib was initiated in 56 % patients in HEM-AP and in 27 % in ACA-AP, nilotinib in 44 % and 73 % respectively. Response and survival do not differ, regardless of the TKI2: 81 % vs 84.3 % patients achieved CHR, 88 % vs 84 % CCyR, 73 % vs 75 % MMR respectively. The estimated 5-year PFS 91.5 % (95%CI: 84.51-99.06 %) and 5-year OS 96.84 % (95%CI: 92.61-100 %). Only BM blasts (p < 0.001) and BM blasts+promyelocytes (p < 0.001) at diagnosis negatively influenced OS. TKI2 as front-line therapy in newly diagnosed AP-CML induce excellent responses and survival, and counterbalance the negative impact of advanced disease phase.

Impact on Outcome of Minimal Residual Disease after Hematopoietic Stem Cell Transplantation with Fludarabine, Amsacrine, and Cytosine Arabinoside-Busulfan Conditioning: A Retrospective Monocentric Study.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) after conditioning with a sequential association of fludarabine, amsacrine, and cytosine arabinoside (FLAMSA) followed by a reduced-intensity conditioning regimen has emerged for patients with high-risk acute myeloid leukemia (AML), especially in refractory or relapsing patients. Here we aimed to address retrospectively the impact of pretransplantation minimal residual disease (MRD) by flow cytometry on the outcomes of high-risk AML patients who underwent allo-HSCT after sequential FLAMSA-busulfan (FLAMSA-Bu)-based conditioning regimens. We included 165 high-risk AML patients who underwent transplantation after FLAMSA-BU in this retrospective single-center "real life" study. All patients received in vivo T cell depletion with antithymocyte globulin (5 mg/kg). MRD detection was based on a leukemia-associated immunophenotype using the European LeukemiaNet recommendations, with a threshold of .1%. Univariate and multivariate analyses were performed using R version 4.1.1 (R Foundation for Statistical Computing, Vienna, Austria). With a median follow-up of 4.0 years post-transplantation, the median overall survival (OS) was 54.9 months. Overall, 41 patients (24.8%) relapsed post-transplantation, with a resulting cumulative incidence of relapse (CIR) of 26.7% at 2 years and 34.0% at 5 years. Detectable MRD preceding allo-HSCT and refractory status were associated with worse median OS and CIR rates compared with patients without detectable MRD; however, OS was not significantly different between pre-HSCT MRD-positive and refractory patients (median, .7 year versus 2.0 years; P = .3). Conversely, pre-HSCT MRD negativity was associated with a reduced 2-year CIR. Neither European LeukemiaNet risk stratification nor age had a significant influence on OS. In the multivariate analysis, only pre-HSCT MRD positivity and lower conditioning regimen intensity were significantly associated with a poorer OS. The cumulative incidence of extensive chronic graft-versus-host disease at 2 years was 26.15%. The estimated nonrelapse mortality (NRM) of the entire cohort at 2 years was 23.1%, with age and unrelated donor identified as risk factors for higher NRM. Our data ahow that FLAMSA-Bu conditioning did not reverse the pejorative effect of detectable pre-HSCT MRD, suggesting that such patients should be offered alternative strategies before HSCT to reach deeper remission.

Donor-Derived Leukemia in a Recipient of Double-Unit Cord Blood Transplantation for Acute Myeloid Leukemia: A Case Study and Literature Review.

We report a case of donor-derived leukemia (DDL) occurring 34 months after double-unit cord blood transplantation (CBT). Molecular analysis using short tandem repeat (STR) sequences proved the acute myeloid leukemia (AML) to be of dominant cord blood origin. Karyotype was normal and molecular analysis showed WT1 and EVI1 overexpression. Cytological and molecular remission were achieved with only induction and consolidation chemotherapy. Relapse occurred after 6 years of remission from one clone with only WT1 overexpression. Potential etiologies for donor cell leukemogenesis in the recipient are discussed, including occult leukemia in the donor or genetic predisposition to hematologic malignancies, impaired immune surveillance, induced or inherited stromal abnormalities, transformation of donor cells during engraftment via altered signals of the host tissues, and fusion of donor cells with residual leukemic cells leading to acquisition of oncogenes. Although cases of DDL occurring after umbilical CBT have already been reported, very few cases have been described arising after double-unit CBT. DDL cases following CBT previously described in the literature have been reviewed.

The CADM1 tumor suppressor gene is a major candidate gene in MDS with deletion of the long arm of chromosome 11.

Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal hematopoietic stem cell disorders characterized by ineffective hematopoiesis leading to peripheral cytopenias and in a substantial proportion of cases to acute myeloid leukemia. The deletion of the long arm of chromosome 11, del(11q), is a rare but recurrent clonal event in MDS. Here, we detail the largest series of 113 cases of MDS and myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN) harboring a del(11q) analyzed at clinical, cytological, cytogenetic, and molecular levels. Female predominance, a survival prognosis similar to other MDS, a low monocyte count, and dysmegakaryopoiesis were the specific clinical and cytological features of del(11q) MDS. In most cases, del(11q) was isolated, primary and interstitial encompassing the 11q22-23 region containing ATM, KMT2A, and CBL genes. The common deleted region at 11q23.2 is centered on an intergenic region between CADM1 (also known as Tumor Suppressor in Lung Cancer 1) and NXPE2. CADM1 was expressed in all myeloid cells analyzed in contrast to NXPE2. At the functional level, the deletion of Cadm1 in murine Lineage-Sca1+Kit+ cells modifies the lymphoid-to-myeloid ratio in bone marrow, although not altering their multilineage hematopoietic reconstitution potential after syngenic transplantation. Together with the frequent simultaneous deletions of KMT2A, ATM, and CBL and mutations of ASXL1, SF3B1, and CBL, we show that CADM1 may be important in the physiopathology of the del(11q) MDS, extending its role as tumor-suppressor gene from solid tumors to hematopoietic malignancies.

Performances of Targeted RNA Sequencing for the Analysis of Fusion Transcripts, Gene Mutation, and Expression in Hematological Malignancies.

RNA sequencing holds great promise to improve the diagnostic of hematological malignancies, because this technique enables to detect fusion transcripts, to look for somatic mutations in oncogenes, and to capture transcriptomic signatures of nosological entities. However, the analytical performances of targeted RNA sequencing have not been extensively described in diagnostic samples. Using a targeted panel of 1385 cancer-related genes in a series of 100 diagnosis samples and 8 controls, we detected all the already known fusion transcripts and also discovered unknown and/or unsuspected fusion transcripts in 12 samples. Regarding the analysis of transcriptomic profiles, we show that targeted RNA sequencing is performant to discriminate acute lymphoblastic leukemia entities driven by different oncogenic translocations. Additionally, we show that 86% of the mutations identified at the DNA level are also detectable at the messenger RNA (mRNA) level, except for nonsense mutations that are subjected to mRNA decay. We conclude that targeted RNA sequencing might improve the diagnosis of hematological malignancies. Standardization of the preanalytical steps and further refinements of the panel design and of the bioinformatical pipelines will be an important step towards its use in standard diagnostic procedures.

Prognostic Value of Genetic Alterations in Elderly Patients with Acute Myeloid Leukemia: A Single Institution Experience.

Although the outcome in younger adults with acute myeloid leukemia (AML) has improved, the benefit associated with standard intensive chemotherapy in older patients remains debatable. In this study, we investigated the incidence and the prognostic significance of genetic characteristics according to treatment intensity in patients aged 60 years or older. On the 495 patients of our cohort, DNMT3A R882 (25.2%), NPM1 (23.7%) and FLT3-ITD (16.8%) were the most frequent molecular mutations found at diagnosis. In this elderly population, intensive chemotherapy seemed to be a suitable option in terms of early death and survival, except for normal karyotype (NK) NPM1-FLT3-ITD+ patients and those aged over 70 within the adverse cytogenetic/molecular risk group. The FLT3-ITD mutation was systematically associated with an unfavorable outcome, independently of the ratio. NK NPM1+/FLT3-TKD+ genotype tends to confer a good prognosis in patients treated intensively. Regarding minimal residual disease prognostic value, overall survival was significantly better for patients achieving a 4 log NPM1 reduction (median OS: 24.4 vs. 12.8 months, p = 0.013) but did not reach statistical significance for progression free survival. This retrospective study highlights that intensive chemotherapy may not be the most appropriate option for each elderly patient and that molecular markers may help treatment intensity decision-making.

Impact of second decline rate of BCR-ABL1 transcript on clinical outcome of chronic phase chronic myeloid leukemia patients on imatinib first-line.

Early molecular response has been associated with clinical outcome in chronic myeloid leukemia (CML) patients treated with tyrosine kinase inhibitors. The BCR-ABL1 transcript rate decline from baseline to 3 months has been demonstrated to be more predictive than a single BCR-ABL1 level at 3 months (M3). However, it cannot be used routinely because ABL1, as an internal gene control, is not reliable for BCR-ABL1 quantification above 10%. This study aimed to compare clinical outcome and molecular response of chronic phase CML patients, depending on the percentage of BCR-ABL1 transcript decrease from month 3 to month 6 using ABL1 as an internal control gene. Two hundred sixteen chronic phase CML patients treated with imatinib 400 mg for whom M3 and month 6 molecular data were available were included in the study. Associations with event-free (EFS), failure-free (FFS), progression-free (PFS), and overall survivals (OS) molecular response 4 log and 4.5 log were assessed. The percentage of BCR-ABL1 decline from month 3 to month 6 was significantly linked to the EFS and the FFS (p < 0.001). A common cut-off of 67% of decline predicted the better risk of event. Patients with a decrease below 67% have worse EFS and FFS as compared to those having a higher decrease (p < 0.001). The impact was confirmed by multivariate analysis. Since the slope between diagnosis and 3 months cannot be reliable using ABL1 as an internal gene control, the second decline rate of BCR-ABL1 transcript between month 3 and month 6 could efficiently identify patients at higher risk of event.

B-ALL With t(5;14)(q31;q32); IGH-IL3 Rearrangement and Eosinophilia: A Comprehensive Analysis of a Peculiar IGH-Rearranged B-ALL.

Background: B-cell acute lymphoblastic leukemia associated with t(5;14)(q31;q32); IGH-IL3 is an exceptional cause of eosinophilia. The IGH enhancer on 14q32 is juxtaposed to the IL3 gene on 5q31, leading to interleukin-3 overproduction and release of mature eosinophils in the blood. Clinical, biological and outcome data are extremely scarce in the literature. Except for eosinophilia, no relevant common feature has been highlighted in these patients. However, it has been classified as a distinct entity in the World Health Organization classification. Cases Presentation: Eight patients with t(5;14)(q31;q32) treated by French or Austrian protocols were retrospectively enrolled. Array comparative genomic hybridization, multiplex ligation-dependent probe amplification or genomic PCR search for IKZF1 deletion were performed in 7. Sixteen patients found through an exhaustive search in the literature were also analyzed. For those 24 patients, median age at diagnosis is 14.3 years with a male predominance (male to female ratio = 5). Eosinophilia-related symptoms are common (neurologic in 26%, thromboembolic in 26% or pulmonary in 50%). Median white blood cells count is high (72 × 109/L) and linked to eosinophilia (median: 32 × 109/L). Peripheral blasts are present at a low level or absent (median: 0 × 109/L; range: 0-37 × 109/L). Bone marrow morphology is marked by a low blast infiltration (median: 42%). We found an IKZF1 deletion in 5 out of 7 analyzable patients Outcome data are available for 14 patients (median follow-up: 28 months): 8 died and 6 are alive in complete remission. Some of these features are concordant with those seen in patients with other IGH-rearranged B-cell acute lymphoblastic leukemias: young age at onset, male sex, low blast count, high incidence of IKZF1 deletion and intermediate prognosis. Conclusion: Based on shared epidemiological and biological features, B-cell acute lymphoblastic leukemia with t(5;14)(q31;q32) is a peculiar subset of IGH-rearranged B-cell acute lymphoblastic leukemia with an intermediate prognosis and particular clinical features related to eosinophilia.

Poor prognosis of chromosome 7 clonal aberrations in Philadelphia-negative metaphases and relevance of potential underlying myelodysplastic features in chronic myeloid leukemia.

Clonal chromosome abnormalities in Philadelphia-negative cells could concern chronic myeloid leukemia patients treated by tyrosine kinase inhibitors. The European LeukemiaNet distinguishes -7/del(7q) abnormalities as a "warning". However, the impact of clonal chromosome abnormalities, and specifically those of -7/del(7q), in Philadelphia-negative cells on clinical outcomes is unclear and based on case-reports showing morphological dysplasia and increased risk of acute myeloid leukemia, suggesting the coexistence of chronic myeloid leukemia and high-risk myelodysplastic syndrome. The aim of this study was to determine whether the impact of -7/del(7q) clonal chromosome abnormalities in Philadelphia-negative cells on the clinical outcome is different from that of other types of abnormalities, and we argue for an underlying associated high-risk myelodysplastic syndrome. Among 102 chronic myeloid leukemia patients with clonal chromosome abnormalities in Philadelphia-negative cells with more than a median of 6 years of follow up, patients with -7/del(7q) more frequently had signs of dysplasia, a lower cumulative incidence of deep molecular response and often needed further treatment lines, with the consequent impact on event-free and progression-free survival. Morphological features of dysplasia are associated with myelodysplastic syndrome/acute myeloid leukemia mutations and compromise the optimal response to tyrosine kinase inhibitors, irrespectively of the type of clonal chromosome abnormalities in Philadelphia-negative cells. However, mutation patterns determined by next-generation sequencing could not clearly explain the underlying high-risk disease. We hereby confirm the pejorative prognostic value of -7/del(7q) clonal chromosome abnormalities in Philadelphia-negative cells and suggest that myelodysplastic features constitute a warning signal that response to tyrosine kinase inhibitors may be less than optimal.

Case report: Purulent transformation of granulocytic sarcoma: An unusual pattern of differentiation in acute promyelocytic leukemia.

RATIONALE: Acute promyelocytic leukemia (APL) is a curable subtype of acute myeloid leukemia. APL is currently treated with combination of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) resulting in the induction of apoptosis and differentiation of the leukemic cells. Differentiation syndrome (so-called ATRA syndrome) is the main life-threatening complication of induction therapy with these differentiating agents. PATIENT CONCERNS: Herein, we report the case of a 49-year-old woman diagnosed with APL with, concomitantly, a bulky cutaneous lesion of 10 cm diameter with a red-to-purple background and a necrotic center, localized on her abdomen. DIAGNOSES: After 10 days of treatment, the cutaneous lesion became purulent. Fluorescence in situ hybridization (FISH) analysis performed on this pus confirmed the presence of malignant features in the involved granulocytes proving their origin from the differentiation of leukemic APL cells, as all the analyzed nuclei showed 2 promyelocytic leukemia (PML)-retinoic acid receptor-a (RARA) fusions signals. INTERVENTION: The association by ATRA and ATO was continued. OUTCOME: Eventually, the evolution was favorable with healing in three weeks. LESSONS: This case report therefore highlights the differentiation phenomenon of promyelocytic blasts within promyelocytic sarcoma with the ATRA-ATO combination and the efficacy of this drug association in resolving both the malignant sarcoma and a secondary local infection.

Impact of cytogenetic abnormalities in adults with Ph-negative B-cell precursor acute lymphoblastic leukemia.

Multiple cytogenetic subgroups have been described in adult Philadelphia chromosome (Ph)-negative B-cell precursor (BCP) acute lymphoblastic leukemia (ALL), often comprising small numbers of patients. In this study, we aimed to reassess the prognostic value of cytogenetic abnormalities in a large series of 617 adult patients with Ph-negative BCP-ALL (median age, 38 years), treated in the intensified Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003/2005 trials. Combined data from karyotype, DNA index, fluorescence in situ hybridization, and polymerase chain reaction screening for relevant abnormalities were centrally reviewed and were informative in 542 cases (88%), allowing classification in 10 exclusive primary cytogenetic subgroups and in secondary subgroups, including complex and monosomal karyotypes. Prognostic analyses focused on cumulative incidence of failure (including primary refractoriness and relapse), event-free survival, and overall survival. Only 2 subgroups, namely t(4;11)/KMT2A-AFF1 and 14q32/IGH translocations, displayed a significantly worse outcome in this context, still observed after adjustment for age and after censoring patients who received allogeneic stem cell transplantation (SCT) in first remission at SCT time. A worse outcome was also observed in patients with low hypodiploidy/near triploidy, but this was likely related to their higher age and worse tolerance to therapy. The other cytogenetic abnormalities, including complex and monosomal karyotypes, had no prognostic value in these intensive protocols designed for adult patients up to the age of 60 years.

Bone Marrow Necrosis in Newly Diagnosed Acute Leukemia: Two Case Reports and Review of the Literature.

Bone marrow necrosis (BMN) in acute leukemia is a rare histopathological entity at the time of initial diagnosis. However, it represents an important diagnostic and prognostic challenge. Two cases of BMN are reported: a 44-year-old patient with B cell precursor (BCP) acute lymphoblastic leukemia (ALL) and a 27-year-old man with FAB-M5 acute myeloid leukemia (AML) who both presented with bone marrow failure and extensive necrosis. From these clinical cases, we conducted a brief review of the literature.

TET2 exon 2 skipping is an independent favorable prognostic factor for cytogenetically normal acute myelogenous leukemia (AML): TET2 exon 2 skipping in AML.

In AML, approximately one-third of expressed genes are abnormally spliced, including aberrant TET2 exon 2 expression. In a discovery cohort (n=99), TET2 exon 2 skipping (TET2E2S) was found positively associated with a significant reduction in the cumulative incidence of relapse (CIR). Age, cytogenetics, and TET2E2S were independent prognostic factors for disease-free survival (DFS), and favorable effects on outcomes predominated in cytogenetic normal (CN)-AML and younger patients. Using the same cutoff in a validation cohort of 86 CN-AML patients, TET2E2Shigh patients were found to be younger than TET2low patients without a difference in the rate of complete remission. However, TET2E2Shigh patients exhibited a significantly lower CIR (p<10-4). TET2E2S and FLT3-ITD, but not age or NPM1 mutation status were independent prognostic factors for DFS and event-free survival (EFS), while TET2E2S was the sole prognostic factor that we identified for overall survival (OS). In both the intermediate-1 and favorable ELN genetic categories, TET2E2S remained significantly associated with prolonged survival. There was no correlation between TET2E2S status and outcomes in 34 additional AML patients who were unfit for IC. Therefore our results suggest that assessments of TET2 exon 2 splicing status might improve risk stratification in CN-AML patients treated with IC.

High frequency of CD34+CD38-/low immature leukemia cells is correlated with unfavorable prognosis in acute myeloid leukemia.

AIM: To evaluate the importance of the CD34+CD38- cell population when compared to the CD34+CD38+/low and CD34+CD38+/high leukemic cell sub-populations and to determine its correlations with leukemia characteristics and known prognostic factors, as well as with response to therapy and survival. METHODS: Two hundred bone marrow samples were obtained at diagnosis from 200 consecutive patients with newly diagnosed acute myeloid leukemia (AML) were studied between September 2008 and December 2010 at our Institution (Hematology Department, Lyon, France). The CD34/CD38 cell profile was analyzed by multiparameter flowcytometry approach using 8C panels and FACS CANTO and Diva software (BD Bioscience). RESULTS: We analyzed CD34 and CD38 expression in bone marrow samples of 200 AML patients at diagnosis, and investigated the prognostic value of the most immature CD34+CD38- population. Using a cut-off value of 1% of CD34+CD38- from total "bulk leukemic cells" we found that a high (> 1%) level of CD34+CD38- blasts at diagnosis was correlated with advanced age, adverse cytogenetics as well as with a lower rate of complete response after induction and shorter disease-free survival. In a multivariate analysis considering age, leukocytosis, the % of CD34+ blasts cells and the standardized cytogenetic and molecular risk subgroups, a percentage of CD34+CD38- leukemic cells > 1% was an independent predictor of DFS [HR = 2.8 (1.02-7.73), P = 0.04] and OS [HR = 2.65 (1.09-6.43), P = 0.03]. CONCLUSION: Taken together, these results show that a CD34/CD38 "backbone" for leukemic cell analysis by multicolour flowcytometry at diagnosis provides useful prognostic information.

Treatment patterns and comparative effectiveness in elderly acute myeloid leukemia patients (age 70 years or older): the Lyon-university hospital experience.

The treatment of very elderly patients (≥70 years) with acute myeloid leukemia remains controversial. We present here 302 patients seen over a 14-year period in order to understand the real-world treatment patterns and outcomes in this patient population. Less than 25% of patients achieved a complete remission. The median overall survival was 12.4, 11.5 and 2.6 months, with a 3-year rates of 27%, 17% and 6%, for non-acute promyelocytic leukemia patients receiving intensive chemotherapy, lower-intensity therapy or best supportive care (BSC), respectively. In all ages, results were not significantly different among patients receiving low-intensity therapy and intensive chemotherapy, but significantly worse in those treated with BSC only. Similarly, intensive chemotherapy and low-intensity therapy gave better survival rates than BSC in patients with favorable- or intermediate-risk cytogenetics and in those with unfavorable cytogenetics (p < 0.0001 and p = 0.04, respectively).

Cytogenetic place in managing myelodysplastic syndromes: an update by the Groupe francophone de cytogénétique hématologique (GFCH).

The myelodysplastic syndromes (MDS) are preleukemic diseases of elderly patients characterized by defective maturation of clonal hematopoietic progenitor cells resulting in peripheral blood cytopenias. Clonal chromosomal abnormalities are heterogeneous and can be detected in less than 50% of patients with de novo MDS and more frequently in secondary MDS (up to 80%). The karyotype plays an important role in the pathogenesis, diagnosis, and prognosis to evaluate the risk of leukemic transformation and, more recently, in treatment allocation. The gold standard for cytogenetic diagnosis in MDS is conventional chromosome banding analyses of bone marrow metaphases. The most frequent abnormalities are deletions and losses of chromosomes 5 (-5/5q-) and 7 (-7/7q-) and various isolated or combined abnormalities. Fluorescent in situ hybridization and array comparative genomic hybridization can reveal cryptic genetic abnormalities but are not recommended in routine diagnosis. New techniques including next generation sequencing revealed somatic driver mutations especially those affecting genes involved in RNA splicing or those harboring important prognostic value (TP53, ASXL1…) with potential applications in clinical practice in the future.