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Platelet-derived growth factor receptor B (PDGFRB) gene rearrangements define a unique subgroup of myeloid and lymphoid neoplasms frequently associated with eosinophilia and characterized by high sensitivity to tyrosine kinase inhibition. To date, various PDGFRB/5q32 rearrangements, involving at least 40 fusion partners, have been reported. However, information on genomic and clinical features accompanying rearrangements of PDGFRB is still scarce. Here, we characterized a series of 14 cases with a myeloid neoplasm using cytogenetic, single nucleotide polymorphism array, and next-generation sequencing. We identified nine PDGFRB translocation partners, including the KAZN gene at 1p36.21 as a novel partner in a previously undescribed t(1;5)(p36;q33) chromosome change. In all cases, the PDGFRB recombination was the sole cytogenetic abnormality underlying the phenotype. Acquired somatic variants were mainly found in clinically aggressive diseases and involved epigenetic genes (TET2, DNMT3A, ASXL1), transcription factors (RUNX1 and CEBPA), and signaling modulators (HRAS). By using both cytogenetic and nested PCR monitoring to evaluate response to imatinib, we found that, in non-AML cases, a low dosage (100-200 mg) is sufficient to induce and maintain longstanding hematological, cytogenetic, and molecular remissions.
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Rearranjo Gênico , Leucemia Mieloide/genética , Doenças Mieloproliferativas-Mielodisplásicas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Adulto , Idoso , Aberrações Cromossômicas , Proteínas do Citoesqueleto/genética , Eosinofilia/genética , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Fusão Oncogênica/genética , Polimorfismo de Nucleotídeo Único , Translocação Genética , Adulto JovemRESUMO
Neutropenia refers to a group of diseases characterized by a reduction in neutrophil levels below the recommended age threshold. The present study aimed to review the diagnosis and management of neutropenia, including a diagnostic toolkit and candidate underlying genes. This study also aimed to review the progress toward the definition of autoimmune and idiopathic neutropenia rising in infancy or in late childhood but without remission, and provide suggestions for efficient diagnostics, including indications for the bone marrow and genetic testing. The management and treatment protocols for common and unique presentations are also reviewed, providing evidence tailored to a single patient.
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Medula Óssea , Neutropenia , Transplante de Medula Óssea , Criança , Humanos , Itália , Oncologia , Neutropenia/diagnóstico , Neutropenia/terapia , SíndromeRESUMO
Autoimmune neutropenia of infancy (AIN) is characterized by low risk of severe infection, tendency to spontaneously resolve and typically onset at ≤4-5 years of age; it is due to auto-antibodies whose detection is often difficult. In case of negativity of 4 antineutrophils autoantibody tests, after having excluded ethnic, postinfection, drug induced, or congenital neutropenia, according to the Italian guidelines the patients will be defined as affected by "idiopathic neutropenia" (IN). We describe the characteristics of 85 IN patients enrolled in the Italian neutropenia registry: they were compared with 336 children affected by AIN. The 2 groups were clinically very similar and the main differences were detection age (later in IN), length of disease (longer in IN) and, among recovered patients, age of spontaneous recovery: the median age at resolution was 2.13 years in AINs and 3.03 years in INs (P = .00002). At bivariate analysis among AIN patients earlier detection age (P = .00013), male sex (P = .000748), absence of leucopenia (P = .0045), and absence of monocytosis (P = .0419) were significantly associated with earlier recovery; in the IN group only detection age (P = .013) and absence of monocytosis (P = .0333) were significant. At multivariate analysis detection age and absence of monocytosis were independently significant (P = 6.7e-05 and 4.4e-03, respectively) in the AIN group, whereas in the IN group only detection age stayed significant (P = .013).
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Neutropenia/congênito , Fatores Etários , Autoimunidade , Síndrome Congênita de Insuficiência da Medula Óssea , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Itália , Leucopenia , Masculino , Neutropenia/diagnóstico , Neutropenia/epidemiologia , Sistema de Registros , Fatores de Risco , Fatores SexuaisAssuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Benzamidas , Humanos , Mesilato de Imatinib , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapiaRESUMO
The incorporation of tyrosine kinase inhibitors (TKIs) in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) led to significant improvement. However, in the pediatric setting, the outcomes of Ph+ ALL are still inferior compared to those of other ALL subtypes even in the TKI era due to higher relapse rate. Herein, we report a very peculiar case of late extramedullary Ph+ ALL relapse in a child, characterized by lymphomatous presentation in the tonsils and lymphoid lineage switch. The diagnostic dilemma between the occurrence of a second malignant neoplasm and the recurrence of the primary disease is further discussed, highlighting the importance of molecular backtracking analysis. This case report emphasizes the high plasticity and polyclonal nature of ALL and expands the heterogeneity of possible clinical presentation of Ph+ ALL at relapse.
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Bone marrow mesenchymal cells (MSCs) can protect leukemic cells from chemotherapy, thus increasing their survival rate. We studied the potential molecular mechanisms underlying this effect in acute lymphoblastic leukemia (ALL) cells. Coculture of ALL cells with MSCs induced on the lymphoblast plasma membrane the expression of a signaling complex formed by hERG1 (human ether-à-go-go-related gene 1) channels, the ß(1)-integrin subunit, and the chemokine receptor CXC chemokine receptor-4. The assembly of such a protein complex activated both the extracellular signal-related kinase 1/2 (ERK1/2) and the phosphoinositide 3-kinase (PI3K)/Akt prosurvival signaling pathways. At the same time, ALL cells became markedly resistant to chemotherapy-induced apoptosis. hERG1 channel function appeared to be important for both the initiation of prosurvival signals and the development of drug resistance, because specific channel blockers decreased the protective effect of MSCs. NOD/SCID mice engrafted with ALL cells and treated with channel blockers showed reduced leukemic infiltration and had higher survival rates. Moreover, hERG1 blockade enhanced the therapeutic effect produced by corticosteroids. Our findings provide a rationale for clinical testing of hERG1 blockers in the context of antileukemic therapy for patients with ALL.
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Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Bloqueadores dos Canais de Potássio/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Animais , Western Blotting , Membrana Celular/metabolismo , Células Cultivadas , Técnicas de Cocultura , Doxorrubicina/farmacologia , Canais de Potássio Éter-A-Go-Go/genética , Canais de Potássio Éter-A-Go-Go/metabolismo , Feminino , Humanos , Integrina beta1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Complexos Multiproteicos/metabolismo , Piperidinas/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prednisona/farmacologia , Piridinas/farmacologia , Interferência de RNA , Receptores CXCR4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Background: GATA2 deficiency is an inborn error of immunity (IEI) characterized by infectious susceptibility and increased risk of myelodysplasia leading to acute myeloid leukaemia (AML). Oral anomalies already described in this disorder include recurrent viral and fungal infections and oral ulcers. Material and Methods: We report a 9-year-old girl presenting with AML with myelodysplasia-related changes, monosomy 7 karyotype on marrow aspirate, numerous flat warts on her hands and multiple dental caries at oral cavity inspection. Dental evaluation and genetic testing (Sanger sequencing) for GATA2 were carried out considering the peculiar clinical presentation. Results: Dental evaluation showed extensive caries and periodontal disease, while genetic studies revealed a known c.1009 C>T (p.Arg337X) mutation in GATA2. After multidisciplinary discussion, affected teeth were extracted before chemotherapy, in general anaesthesia, together with scaling and root planning of the alveolar sockets. Subsequently, the patient underwent hematopoietic stem cell transplantation (HSCT) from her HLA-matched GATA2 wild-type sibling, who did not bear any dental anomalies. No dento-alveolar infections were encountered during post-chemotherapy aplasia. Conclusions: This case first describes the association between GATA2 deficiency and extensive dental caries with periodontal disease, highlighting the importance of an early dental evaluation and intervention in children with leukaemia. Key words:GATA2 deficiency, Inborn errors of immunity, teeth, dental decay, multidisciplinary approach.
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BACKGROUND: Flow cytometric analysis of leukemia-associated immunophenotypes and polymerase chain reaction-based amplification of antigen-receptor genes rearrangements are reliable methods for monitoring minimal residual disease. The aim of this study was to compare the performances of these two methodologies in the detection of minimal residual disease in childhood acute lymphoblastic leukemia. DESIGN AND METHODS: Polymerase chain reaction and flow cytometry were simultaneously applied for prospective minimal residual disease measurements at days 15, 33 and 78 of induction therapy on 3565 samples from 1547 children with acute lymphoblastic leukemia enrolled into the AIEOP-BFM ALL 2000 trial. RESULTS: The overall concordance was 80%, but different results were observed according to the time point. Most discordances were found at day 33 (concordance rate 70%) in samples that had significantly lower minimal residual disease. However, the discordance was not due to different starting materials (total versus mononucleated cells), but rather to cell input number. At day 33, cases with minimal residual disease below or above the 0.01% cut-off by both methods showed a very good outcome (5-year event-free survival, 91.6%) or a poor one (5-year event-free survival, 50.9%), respectively, whereas discordant cases showed similar event-free survival rates (around 80%). CONCLUSIONS: Within the current BFM-based protocols, flow cytometry and polymerase chain reaction cannot simply substitute each other at single time points, and the concordance rates between their results depend largely on the time at which they are used. Our findings suggest a potential complementary role of the two technologies in optimizing risk stratification in future clinical trials.
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Citometria de Fluxo , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Introduction: ÎµÎ³Î´ß thalassemia is a rare form of ß-thalassemia mostly described in children originating from Northern Europe. Only anecdotic cases from the Mediterranean area are reported. The diagnosis is challenging, considering the rarity of the disease and its heterogeneous clinical presentation. Most patients have neonatal microcytic anemia, sometimes requiring in utero and/or neonatal transfusions, and typically improving with age. Case Description: We report on an Italian newborn presenting with severe neonatal anemia that required red blood cell transfusion. After the first months of life, hemoglobin levels improved with residual very low mean corpuscular volume. ß and α thalassemia, IRIDA syndrome, and sideroblastic anemia were excluded. Finally, a diagnosis of ÎµÎ³Î´ß thalassemia was made after microarray analysis of single nucleotide polymorphisms revealed a 26 kb single copy loss of chromosome 11p15.4, including the HBD, HBBP1, HBG1, and HBB genes. Conclusions: Despite its rarity, the diagnosis of ÎµÎ³Î´ß thalassemia should be considered in newborns with severe neonatal anemia requiring in utero and/or neonatal transfusions, but also in older infants with microcytic anemia, after excluding more prevalent red blood cell disorders.
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Inborn errors of immunity (IEI) are genetic disorders characterized by a wide spectrum of clinical manifestations, ranging from increased susceptibility to infections to significant immune dysregulation. Among these, primary immune regulatory disorders (PIRDs) are mainly presenting with autoimmune manifestations, and autoimmune cytopenias (AICs) can be the first clinical sign. Significantly, AICs in patients with IEI often fail to respond to first-line therapy. In pediatric patients, autoimmune cytopenias can be red flags for IEI. However, for these cases precise indicators or parameters useful to suspect and screen for a hidden congenital immune defect are lacking. Therefore, we focused on chronic/refractory AIC patients to perform an extensive clinical evaluation and multiparametric flow cytometry analysis to select patients in whom PIRD was strongly suspected as candidates for genetic analysis. Key IEI-associated alterations causative of STAT3 GOF disease, IKAROS haploinsufficiency, activated PI3Kδ syndrome (APDS), Kabuki syndrome and autoimmune lymphoproliferative syndrome (ALPS) were identified. In this scenario, a dysregulated immunophenotype acted as a potential screening tool for an early IEI diagnosis, pivotal for appropriate clinical management and for the identification of new therapeutic targets.
Assuntos
Anormalidades Múltiplas , Síndrome Linfoproliferativa Autoimune , Face/anormalidades , Doenças Hematológicas , Doenças da Imunodeficiência Primária , Doenças Vestibulares , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/imunologia , Adolescente , Adulto , Síndrome Linfoproliferativa Autoimune/diagnóstico , Síndrome Linfoproliferativa Autoimune/genética , Síndrome Linfoproliferativa Autoimune/imunologia , Criança , Pré-Escolar , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/imunologia , Feminino , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/genética , Doenças Hematológicas/imunologia , Humanos , Lactente , Masculino , Doenças da Imunodeficiência Primária/diagnóstico , Doenças da Imunodeficiência Primária/genética , Doenças da Imunodeficiência Primária/imunologia , Estudos Prospectivos , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/genética , Doenças Vestibulares/imunologiaRESUMO
Primary autoimmune neutropenia (pAN) is typified by onset in early infancy and a mild/moderate phenotype that resolves within 3 years of diagnosis. In contrast, secondary AN is classically an adult disease associated with malignancy, autoimmunity, immunodeficiency, viral infection, or drugs. This study describes a cohort of 79 children from the Italian Registry who, although resembling pAN, did not fully match the criteria for pAN because neutropenia either appeared after age 5 years (LO-Np) or lasted longer than 3 years (LL-Np). These 2 categories compared with classical pAN showed a far inferior rate of resolution (P < .001), lower severity of neutropenia (P = .03), leukopenia (P < .001), lymphopenia (P < .001) with low B+ (P = .001), increased need of granulocyte colony-stimulating factor (P = .04), and increased frequency of autoimmunity over the disease course (P < .001). A paired comparison between LO-Np and LL-Np suggested that LO-Np had a lower rate of resolution (P < .001) and lower white blood cell (P < .001) and lymphocyte (P < .001) values, higher occurrence of apthae (P = .008), and a stronger association with autoimmune diseases/markers (P = .001) than LL-Np, thus suggesting a more pronounced autoimmune signature for LO-Np. A next-generation sequencing panel applied in a small subgroup of LO-Np and LL-Np patients identified variants related to immune dysregulations. Overall, these findings indicate that there are important differences among pAN LL-Np and LO-Np. Forms rising after 3 years of age, with low tendency to resolution, require tight monitoring and extensive immune investigations aimed to early identify underlying immunologic disease.
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Autoimunidade , Neutropenia , Adulto , Criança , Pré-Escolar , Síndrome Congênita de Insuficiência da Medula Óssea , Humanos , Itália/epidemiologia , Neutropenia/diagnóstico , Neutropenia/epidemiologia , Sistema de RegistrosRESUMO
BACKGROUND: The diagnosis of myelodysplastic syndromes (MDS) is mainly based on morphology and cytogenetic analysis. Several efforts to analyze MDS by flow cytometry have been reported in adults. These studies have focused on the identification of abnormalities in the maturation pathway of antigen expression of myelo-monocytic cells, and characterization of blast populations. Therefore, phenotype has been proposed as a diagnostic and prognostic criterion tool for adult MDS. The current article provides data concerning the blast phenotype in pediatric MDS. PROCEDURE: We evaluated by multiparameter flow cytometry 26 MDS pediatric patients with more than 2% of blast cells at bone marrow morphological examination (17 de novo MDS and 9 secondary MDS) and 145 pediatric de novo acute myeloid leukemia (AML) cases (M3 excluded). As control group, 12 healthy age-matched donors for allogenic bone marrow transplantation (BMD) and 6 regenerating bone marrow samples, collected from children with acute lymphoblastic leukemia (ALL) in remission after induction chemotherapy, were studied. RESULTS: We identified a blast immunophenotype typically expressed in most MDS cases and a strong correlation between CD7 expression and poor outcome. CD34+ compartment in MDS bone marrow was also analyzed: a significant decrease of B-cell precursors was detected in MDS patients independent of age. CONCLUSIONS: Our data suggest that the blasts phenotypic features can constitute a diagnostic and prognostic tool also for pediatric MDS.
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Crise Blástica/diagnóstico , Síndromes Mielodisplásicas/diagnóstico , Adolescente , Antígenos CD34/análise , Antígenos CD34/imunologia , Antígenos CD7/análise , Antígenos CD7/imunologia , Crise Blástica/metabolismo , Crise Blástica/patologia , Diferenciação Celular , Criança , Pré-Escolar , Feminino , Humanos , Imunofenotipagem , Masculino , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/patologia , Estadiamento de Neoplasias , Células Precursoras de Linfócitos B/citologia , Células Precursoras de Linfócitos B/imunologia , Prognóstico , Taxa de SobrevidaAssuntos
Biomarcadores Tumorais/biossíntese , Regulação Leucêmica da Expressão Gênica , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Adolescente , Biomarcadores Tumorais/genética , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos RetrospectivosAssuntos
Fator de Transcrição PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adulto , Criança , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Masculino , Fator de Transcrição PAX5/biossíntese , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND AND OBJECTIVES: CD58, a member of the Ig superfamily, is expressed by hematopoietic and non- hematopoietic cells. It has been demonstrated to be over-expressed in precursor-B acute lymphoblastic leukemia (ALL) blasts when compared to in their normal counterparts, suggesting its potential use in the detection of minimal residual disease (MRD) by flow cytometry (FC). To assess the reliability and accuracy of CD58 for this purpose, we studied its expression in a large series of normal and ALL bone marrow (BM) samples using quantitative FC. DESIGN AND METHODS: We studied 180 precursor-B ALL BM samples at diagnosis (8 pro-B, 164 early-B, 8 mature-B ALL) and 123 follow-up BM samples (n=54 at day +15 and n=69 at day +78), as well as 51 normal BM samples and 7 regenerating BM samples from patients with T-ALL at week 12. We used four-color quantitative FC, focusing analysis on CD58 expression. In follow-up samples from day +78, the MRD level was simultaneously evaluated by real time quantitative polymerase chain reaction (RQ-PCR) amplification of antigen receptor genes. RESULTS: CD58 expression was significantly higher in ALL blasts than in normal B lymphocytes, while no significant differences between regenerating and normal B lymphocytes were observed. CD58 was expressed in 99.4% of the precursor-B ALL cases and 93.5% of these showed over-expression compared to normal. No significant modulation of CD58 expression during remission induction therapy was noted. Finally, 66 (95.6%) of 69 BM samples simultaneously analyzed using both FC and RQ-PCR at day +78 showed concordant results regarding MRD. INTERPRETATION AND CONCLUSIONS: Our results confirm and further evidence the role of CD58 in the diagnosis and monitoring of precursor-B ALL. In particular, we demonstrated its stability and accuracy in MRD detection at clinically relevant time points. These findings indicate that CD58 is a powerful tool for MRD detection in precursor-B ALL.
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Linfócitos B/química , Biomarcadores Tumorais/análise , Células da Medula Óssea/química , Antígenos CD58/análise , Células-Tronco Neoplásicas/química , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Regeneração/fisiologia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medula Óssea/fisiologia , Criança , Pré-Escolar , Estudos de Coortes , Sistemas Computacionais , Estudos de Viabilidade , Feminino , Citometria de Fluxo , Rearranjo Gênico , Humanos , Lactente , Masculino , Neoplasia Residual , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Indução de RemissãoRESUMO
The aim of this study was to investigate gene expression changes in disseminated neuroblastoma by cDNA array technique. Three stage IV neuroblastomas and one neuroblastoma cell line (SK-N-FI) were analyzed. Expression profiles were confirmed by semiquantitative RT-PCR and in some instances by Northern blotting. Comparison of expression profiles identified several genes which were highly expressed as well as some which were down-regulated in tumor samples relatively to SK-N-FI cells. The tumors studied lacked N-myc overexpression, while showing up-regulation of basic transcription factors, growth factors and receptors such as NSEP, c-myc binding protein MM1, thymosin beta10 (TMSB10), TNF-R superfamily member 10A (TNFRSF10A) and FZ9. These results suggest that cDNA array technology is a powerful tool to identify a set of genes involved in neuroblastoma genesis and progression. Thus, the sensitive cDNA array may provide new insight into many aspects of pediatric tumors and play crucial role in the administration of adjuvant therapy of patients with neuroblastoma.
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Perfilação da Expressão Gênica/métodos , Neuroblastoma/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Neoplásico/metabolismo , Pré-Escolar , Regulação Neoplásica da Expressão Gênica , Substâncias de Crescimento/genética , Humanos , Lactente , Estadiamento de Neoplasias , Neuroblastoma/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , Receptores de Superfície Celular/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Changes of antigen expression on residual blast cells of acute lymphoblastic leukemia (ALL) occur during induction treatment. Many markers used for phenotyping and minimal residual disease (MRD) monitoring are affected. Glucocorticoid (GC)-induced expression modulation has been causally suspected, however, subclone selection may also cause the phenomenon. METHODS: We investigated this by following the phenotypic evolution of leukemic cells with flow cytometry from diagnosis to four time points during and after GC containing chemotherapy in the 20 (of 360 consecutive) B-cell precursor patients with ALL who had persistent MRD throughout. RESULTS: The early expression changes of CD10 and CD34 were reversible after stop of GC containing chemotherapy. Modulation of CD20 and CD45 occurred mostly during the GC phase, whereas CD11a also changed later on. Blast cells at diagnosis falling into gates designed according to "shifted" phenotypes from follow-up did not form clusters and were frequently less numerous than later on. CONCLUSIONS: Our data support the idea that drug-induced modulation rather than selection causes the phenomenon. The good message for MRD assessment is that modulation is transient in at least two (CD10 and CD34) of the five prominent antigens investigated and reverts to initial aberrant patterns after stop of GC therapy, whereas CD20 expression gains new aberrations exploitable for MRD detection.
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Antígenos CD/biossíntese , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/uso terapêutico , Neoplasia Residual/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Adolescente , Antígenos CD/imunologia , Criança , Pré-Escolar , Citometria de Fluxo , Humanos , Lactente , Neoplasia Residual/diagnóstico , Neoplasia Residual/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologiaRESUMO
PURPOSE: Speed of blast clearance is an indicator of outcome in childhood acute lymphoblastic leukemia (ALL). Availability of measurement of minimal residual disease (MRD) at an early time point with a reduced-cost method is of clinical relevance. In the AIEOP-BFM-ALL (Associazione Italiana Ematologia Oncologia Pediatrica and Berlin-Frankfurt-Münster Study Group) 2000 trial, patients were stratified by levels of polymerase chain reaction (PCR) MRD at day +33 and +78. AIEOP studied the prognostic impact of MRD measured by flow cytometry (FCM) at day 15 of induction therapy. PATIENTS AND METHODS: Bone marrow samples from 830 Italian patients were collected on day 15, after 14 days of steroids, and one dose of intrathecal methotrexate, vincristine, daunorubicine, and asparaginase. Cells were analyzed by four-color FCM for detection of leukemia-associated immunophenotypes. RESULTS: Three patient risk groups were identified by FCM: standard (< 0.1% blast cells; 42% of the total), intermediate (0.1 to < 10%; 47%), and high (> or = 10%; 11%). Their 5-year cumulative incidences of relapse were 7.5% (SE, 1.5), 17.5% (SE, 2.1), and 47.2% (SE, 5.9), respectively. In multivariate analysis, FCM was the most important prognostic factor among those available by day 15, with two-fold and five-fold increase in the risk of relapse compared with patients with less than 0.1%. PCR MRD, when added to the model, had significant prognostic impact; yet high levels of FCM MRD retained an independent ability to detect a significantly higher risk of relapse. CONCLUSION: Measurement of FCM MRD in day 15 bone marrow was the most powerful early predictor of relapse, applicable to virtually all patients; it may complement PCR MRD-based stratification including later time points, thus allowing additional treatment tailoring.