Carolina Belli

Partial and total monosomal karyotypes in myelodysplastic syndromes: comparative prognostic relevance among 421 patients.

Myelodysplastic syndromes (MDS) include a group of heterogeneous hematological disorders with a variable risk of leukemic evolution and short survival. Around 40–50% of patients show abnormal karyotypes that are mostly characterized by monosomies or deletions. Cytogenetic findings are an independent prognostic factor and the International prognostic scoring system (IPSS) differentiates three cytogenetic categories, despite the Intermediate one being heterogeneous. The aim of this study, including 421 Argentinean patients with primary MDS, is to characterize the cytogenetic profile, to test its prognostic value and to compare partial and monosomal karyotypes against other cytogenetic findings. An abnormal karyotype (median survival: 26 months) was observed in 176 patients. The presence of complex karyotypes, number of alterations, and the IPSS cytogenetic groups showed significant differences for predicting outcome. Behavior of patients with isolated deletions (median survival: 49 months) did not differ from those with normal karyotype (56 months, P = 0.654) or Good prognostic findings (43 months, P = 0.371). However, a worse prognosis was observed when another alteration was added (31 months, P = 0.043). Karyotypes with autosomal monosomies (median survival: 16 months) had a prognostic impact similar to other Poor cytogenetic findings (17 months, P = 0.626). In our population classified according to French‐American‐British (FAB) or World Health Organization (WHO), this new categorization of cytogenetic abnormalities, recognizing three different risk groups, showed an independent prognostic impact and a better discriminating power than the IPSS categories. It can be concluded that all isolate deletions (excluding 7q‐) are good prognostic findings and all monosomies (excluding Y chromosome loss) are bad indicators. Am. J. Hematol., 2011.

Evaluation of constitutional chromosome aberrations in hematologic disorders

We have reviewed 4164 patients with various hematologic disorders cytogenetically studied in our laboratory during the last 25 years to analyze the frequency of constitutional chromosome aberrations (CCA) and to evaluate their association with hematologic malignancies. Our population of patients included 1133 pediatric patients and 3031 adults. Twenty-four (0.58%) cases showed CCA. They included four patients with Robertsonian translocations, one patient with a balanced translocation, two patients with sex chromosome abnormalities, and 17 cases with Down syndrome (DS). Nonsignificant differences among the frequency of patients with CCA from our hematologic series and those observed in the two largest combined surveys of livebirth published (0.65-0.84%) were found. The incidence of DS patients in our population (0.41%) was approximately three times higher than of that observed at birth (0.12-0.17%; P<0.001). The total incidence of constitutional chromosome abnormalities in the non-DS hematologic patients was 0.168% (7 of 4164) lower than of that observed in the newborn population (0.51-0.67%; P<0.001). Nonsignificant differences were found when the incidences of structural aberrations and sex chromosome anomalies were individually compared with the data of the overall population. Our results suggest that the presence of a CCA, other than DS, would not predispose patients to hematologic malignancies.

Polymorphisms in TNF and IFNG are associated with clinical characteristics of aplastic anemia in Argentinean population

Abstract The impaired hematopoiesis in acquired aplastic anemia (AA) results from immune-mediated mechanisms. We characterized polymorphisms implicated in controlling type-1 cytokine production in 69 patients with AA. Our data suggest that the studied polymorphisms are not associated with susceptibility in the overall AA population. However, the presence of the higher expressing TNF − 308A allele was associated with younger age (p = 0.0297) and more profound neutropenia (p = 0.0312), and over-represented in patients with very severe AA (p = 0.0168). The higher producing IFNG 12 CA-repeat allele showed strong linkage disequilibrium with the + 874T allele, and was associated with a lower hemoglobin level (p = 0.0351). Also, the presence of at least one higher expressing variant was more frequent among patients responding to immunosuppressive treatment (p = 0.0519). Our findings suggest that the presence of higher expressing variants of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in AA patient genotypes could be related to clinical parameters, disease severity and therapy outcomes.

The presence of -308A TNFα is associated with anemia and thrombocytopenia in patients with myelodysplastic syndromes

Myelodysplastic syndromes (MDS) constitute a heterogeneous group of clonal hematological diseases characterized by refractory cytopenia(s). MDS patients show increased levels of tumor necrosis factor alpha (TNFα) which is a multifunctional proinflammatory cytokine. The aim of this work is to examine the presence of -308A/G TNFα variants and to analyze whether it is associated with clinical parameters in a cohort of 101 Argentinean de novo MDS patients. The A/A+A/G genotype at TNFα -308 was overrepresented 2-fold in our population (p=0.0499, odds ratio-OR: 2.107) and these differences were more evident in RA-FAB subtype (p=0.0424, OR: 2.502). The presence of the high expressing -308A allele was associated with lower hemoglobin level (8.3 vs 9.9g/dL; p=0.0206), reduced platelet counts (89,000 vs 130,000/μL; p=0.0381) and younger age (59 vs 68years; p=0.0122) at diagnosis. Also, these patients showed 3.8-fold higher risk of transfusion requirement (76% vs 46%, p=0.0105) during the follow up. In conclusion, the presence of an inherited -308A TNFα, which increases its transcription level, was associated with the MDS phenotype in our cohort of Argentine MDS patients. Also, an overexpression of TNFα may promote an underlying proinflammatory state that cooperates with intrinsic defects within MDS progenitors to increase the severity of certain phenotypic features of the disease.

A single, multiplex analysis for all relevant activating NRAS gene mutations using heteroduplex generators

We describe a multiplex polymerase chain reaction (PCR)‐based test that detected all relevant NRAS activating mutations using a single PCR followed directly by electrophoresis. The test uses a Universal Heteroduplex Generator (UHG) to detect exon‐2 (codon 61) NRAS mutations in multiplex with an UHG for exon‐1 (codons 12 and 13). The method differentiated all 19 relevant mutations in these exons and showed a mutation independent sensitivity of approximately 6%. The sensitive, specific detection of all NRAS activating mutations using this single rapid test represents a minimum workload and could be applied readily for large‐scale screening and for routine analysis.

Novel Variant Ph Translocation t(9;22;11)(q34;q11.2;p15)inv(9)(p13q34) in Chronic Myeloid Leukemia Involving a One-Step Mechanism

Chronic myeloid leukemia (CML) is a clonal malignant disorder of a pluripotent hematopoietic stem cell characterized by the presence of a Philadelphia (Ph) chromosome. Less than 10% of patients present variant Ph chromosomes involving 1 or more additional chromosomes, other than chromosomes 9 and 22, with uncertain prognosis. There are mainly 1- or 2-step mechanisms proposed to explain the genesis of variant Ph chromosomes depending on whether the involved chromosomes are simultaneously broken and rejoined or if a standard t(9;22) occurs first. By combined standard cytogenetic and FISH analysis we detected a novel variant Ph translocation among chromosomes 9, 11 and 22 in a patient with CML without progression to an accelerated phase of the disease after 7 years, with the derivative chromosome 9 also having an acquired pericentric inversion. This novel case illustrates the use of FISH in metaphase to confirm a new rearrangement not previously described in variant Ph formation and that the present karyotype could have originated by a 1-step mechanism with 4 simultaneous breakages without deletion of ABL1.

Transforming growth factor-|[beta]|1 functional polymorphisms in myeloablative sibling hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) with sibling donors (s.d.) is a life-saving intervention for patients with hematological malignancies. Numerous genetic factors have a role in transplant outcome. Several functional polymorphisms have been identified in TGF-β1 gene, such as single-nucleotide polymorphism (SNP) at +29C>T within exon 1. Two hundred and forty five patient/donor pairs who underwent a s.d. HSCT in our centers were genotyped for this SNP. In the myeloablative cohort, +29CC donors were associated with an increase in severe chronic GvHD (32% vs 16%, hazard ratio (HR) 9.0, P=0.02). Regarding survival outcomes, +29CC patients developed higher non relapse mortality (NRM) (1–5 years CC 28–32% vs TC/TT 7–10%; HR 5.1, P=0.01). Recipients of +29TT donors experienced a higher relapse rate (1–5 years TT 37–51% vs TC 19–25% vs CC 13%–19%; HR 2.4, P=0.01) with a decreased overall survival (OS) (1–5 years TT 69–50% vs TC/CC 77–69%; HR 1.9, P=0.05). Similar to previous myeloablative unrelated donors HSCT results, we confirmed that +29CC patients had higher NRM. In addition we found that +29TT donors might be associated with a higher relapse rate and lower OS. These results should be confirmed in larger series. Identification of these SNPs will allow personalizing transplant conditioning and immunosuppressant regimens, as well as assisting in the choice of the most appropriate donor.

Application of the revised International Prognostic Scoring System for myelodysplastic syndromes in Argentinean patients

Dear Editor, The International Prognostic Scoring System (IPSS) [1], the gold standard for risk assessment in myelodysplastic syndromes (MDS), has been recently revised (IPSS-R). The authors proposed a new prognostic model including novel components: five cytogenetic prognostic subgroups with specific classification of a number of less common cytogenetic subsets [2, 3]; the 2–<5%; depth of cytopenias at clinically relevant cut-points for haemoglobin level, platelet count, and absolute neutrophil count [2]. As the score [2] was established in MDS patients including all French–American–British classification subtypes [4], the aim of this study was to apply the IPSS-R in Argentinean MDS patients classified according to the World Health Organization (WHO) classification [5]. We retrospectively analysed a cohort of 371 de novo MDS patients [6] diagnosed between 1981 and 2012. According to the WHO classification, 43 patients were classified as refractory cytopenia with unilineage dysplasia/ refractory anaemia with ringed sideroblasts, 17 as del(5q) syndrome, 201 as refractory cytopenia with multilineage dysplasia, 44 as RAEB type 1, and 66 as RAEB type 2. The median age was 70 (17–92) years with 72 % of patients above 60, the gender ratio was 1.4 (M/F: 214/ 157), and 157 (42 %) patients showed an abnormal karyotype. During the follow-up (median 23.3 months), 80 (22 %) showed

Influence of Acute Myeloid Leukemia Progression on the Prognosis of 831 Patients With Myelodysplastic Syndromes From the Argentine Database

Background A large group of patients with myelodysplastic syndromes (MDS) will die of causes intrinsic to bone marrow failure. One third of patients will develop acute myeloid leukemia (AML), which is associated with an extremely poor outcome and a short survival. Our objectives were to analyze the prognostic variables and scoring systems in the attempt to determine the influence of progression on the overall survival of MDS patients. Patients and Methods We performed a retrospective analysis of 831 MDS patients, including those from the Argentine Registry. Results Of the 831 MDS patients, 158 (19.0%) experienced transformation, with a median overall survival of 17.9 months from diagnosis and 3.5 months after progression. The survival of patients with adverse karyotypes or greater risk, according to the International Prognostic Scoring System‐revised (IPSS‐R) or World Health Organization‐based Prognostic Scoring System (WPSS) was not affected when stratified by patients with and without evolution to AML (P > .05). In contrast, the survival of lower risk patients was significantly reduced for those patients with progression to AML (P < .001) and those younger (P = .024) than those who died of non–AML‐related causes. The intermediate‐risk patients were heterogeneously distributed; however, an upgrade from a lower IPSS‐R to a higher WPSS‐hemoglobin risk category was associated with a worse outcome, not affected by progression (P = .420), with a median event‐free survival of 16 months. Conclusion The use of the IPSS‐R and WPSS systems simultaneously might help in identifying those patients who require more aggressive treatment. Nevertheless, more efforts are needed to improve the identification of those lower risk patients whose survival is significantly reduced by progression to AML. Micro‐Abstract In our retrospective review of 831 patients with myelodysplastic syndromes, 158 developed progression with a very poor outcome (median survival after evolution, 3.5 months). The survival of patients with adverse karyotypes or with greater International Prognostic Scoring System‐revised or World Health Organization‐based Prognostic Scoring System risk was not affected when stratified by patients with and without evolution to acute myeloid leukemia. Our results could help in individualizing those patients who require more aggressive treatment.

Prognostic Implications of Cytogenetic Features in Myelodysplastic Syndromes

Myelodysplastic Syndromes (MDS) are a heterogeneous group of hematologic diseases characterized by refractory cytopenia(s) and variable risk of leukemic progression. Cytogenetic analysis is important in day-to-day clinical practice helping to define subgroups of MDS patients who share similarities in the course of the disease. There are recurring aberrations affecting chromosomes 5, 7, 8, and 20. While all of them do not suggest a therapeutic approach, their presence has been considered as a risk indicator since the original international prognostic scoring system (IPSS) was published. The most recent cytogenetic stratifications tried to find the prognostic significance of less frequent alterations which have been longer included in the intermediate group. Moreover, monitoring of karyotype changes is suggested to evaluate cytogenetic response to treatments and the acquisition of new aberrations associated to an unfavorable outcome. This review focuses on different cytogenetic risk stratifications that have been published during the past 20 years and the molecular background of the most relevant chromosomal findings.