Telomeric repeat-containing RNA is dysregulated in acute myeloid leukemia.

TERRA (telomeric repeat-containing RNA) is a class of long noncoding RNAs transcribed from subtelomeric and telomeric regions. TERRA binds to the subtelomeric and telomeric DNA-forming R-loops (DNA-RNA hybrids), which are involved in telomere maintenance and telomerase function, but the role of TERRA in human cells is not well characterized. Here, we comprehensively investigated for the first time TERRA expression in primary human hematopoietic cells from an exploratory cohort of patients with acute myeloid leukemia (AML), patients with acute lymphoblastic leukemia (ALL), patients with telomere biology disorder (TBD), and healthy subjects. TERRA expression was repressed in primary human hematopoietic cells, including healthy donors, patients with ALL, and patients with TBD, irrespective of their telomere length, except for AML. A second cohort comprising 88 patients with AML showed that TERRA was overexpressed in an AML subgroup also characterized by higher R-loop formation, low TERT and RNAseH2 expression, and a paucity of somatic splicing factor mutations. Telomere length did not correlate with TERRA expression levels. To assess the role of TERRA R-loops in AML, we induced R-loop depletion by increasing RNAseH1 expression in 2 AML cell lines. Decreased TERRA R-loops in AML cell lines resulted in increased chemosensitivity to cytarabine. Our findings indicate that TERRA is uniformly repressed in primary human hematopoietic cells but abnormally expressed in an AML subset with low telomerase.

Survival benefit of pediatric-based regimen for adults with acute lymphoblastic leukemia: A single-center retrospective cohort

ABSTRACT Introduction: Improving survival of Acute Lymphoblastic Leukemia (ALL) in adult patients has been a challenge. Despite intensive chemotherapy treatment, overall survival is poor. However, several studies demonstrate that young adult patients have better survival when treated with pediatric-based intensive regimens. Considering these results, We decided to treat newly diagnosed ALL patients according to age and risk factors. The goal of this study was to describe the results of this intensive chemotherapy treatment approach for ALL adult patients diagnosed at our institution. Methods: Fifty-eight ALL patients, diagnosed from 2004 to 2013, were included in the analysis. Patients were assigned to either the St. Jude Total Therapy XIIIB high-risk arm (St Jude) or the CALGB 8811 (CALGB). The Kaplan-Meier survival curve was used for the survival analyses and the Cox proportional hazard regression, for multivariable analysis. Results: The overall survival was 22.9% at 10 years. The St. Jude improved survival, compared to the CALGB (p = 0.007), with 32.6% vs. 7.4% survival rate at 10 years. However, no survival benefit was found for patients younger than 20 years old (p = 0.32). The multivariable analysis demonstrated that undetectable minimal residual disease (MRD) and hematopoietic stem cell transplantation (HSCT) had beneficial impact on survival (p = 0.0007 and p = 0.004, respectively). Conclusion: ALL is a disease of poor prognosis for adults. The joint effort to standardize treatment and seek solutions is the way to start improving this scenario.

Expert Recommendations for the Diagnosis, Treatment, and Management of Adult B-Cell Acute Lymphoblastic Leukemia in Latin America.

PURPOSE: Despite strong induction chemotherapy response rates, only 30%-40% of patients with adult B-cell acute lymphoblastic leukemia (ALL) attain long-term remission. This study analyzes ALL in Latin America (LA) and recommends diagnosis, treatment, and management protocols. METHODS: The Americas Health Foundation organized a panel of hematologists from Argentina, Brazil, Chile, Colombia, and Mexico to examine ALL diagnosis and therapy and produce recommendations. RESULTS: Lack of regional data, unequal access to diagnosis and therapy, inadequate treatment response, and uneven health care distribution complicate adult ALL management. The panel recommended diagnosis, first-line and refractory treatment, and post-transplantation maintenance. Targeted treatments, including rituximab, blinatumomab, and inotuzumab ozogamicin, are becoming available in LA and must be equitably accessed. CONCLUSION: This review adapts global information on treating ALL to LA. Governments, the medical community, society, academia, industry, and patient advocates must work together to improve policies.

Clinical significance of mitochondrial DNA content in acute promyelocytic leukaemia.

Although a growing body of evidence demonstrates that altered mtDNA content (mtDNAc) has clinical implications in several types of solid tumours, its prognostic relevance in acute promyelocytic leukaemia (APL) patients remains largely unknown. Here, we show that patients with higher-than-normal mtDNAc had better outcomes regardless of tumour burden. These results were more evident in patients with low-risk of relapse. The multivariate Cox proportional hazard model demonstrated that high mtDNAc was independently associated with a decreased cumulative incidence of relapse. Altogether, our data highlights the possible role of mitochondrial metabolism in APL patients treated with ATRA.

Survival benefit of pediatric-based regimen for adults with acute lymphoblastic leukemia: A single-center retrospective cohort.

INTRODUCTION: Improving survival of Acute Lymphoblastic Leukemia (ALL) in adult patients has been a challenge. Despite intensive chemotherapy treatment, overall survival is poor. However, several studies demonstrate that young adult patients have better survival when treated with pediatric-based intensive regimens. Considering these results, We decided to treat newly diagnosed ALL patients according to age and risk factors. The goal of this study was to describe the results of this intensive chemotherapy treatment approach for ALL adult patients diagnosed at our institution. METHODS: Fifty-eight ALL patients, diagnosed from 2004 to 2013, were included in the analysis. Patients were assigned to either the St. Jude Total Therapy XIIIB high-risk arm (St Jude) or the CALGB 8811 (CALGB). The Kaplan-Meier survival curve was used for the survival analyses and the Cox proportional hazard regression, for multivariable analysis. RESULTS: The overall survival was 22.9% at 10 years. The St. Jude improved survival, compared to the CALGB (p = 0.007), with 32.6% vs. 7.4% survival rate at 10 years. However, no survival benefit was found for patients younger than 20 years old (p = 0.32). The multivariable analysis demonstrated that undetectable minimal residual disease (MRD) and hematopoietic stem cell transplantation (HSCT) had beneficial impact on survival (p = 0.0007 and p = 0.004, respectively). CONCLUSION: ALL is a disease of poor prognosis for adults. The joint effort to standardize treatment and seek solutions is the way to start improving this scenario.

STMN1 is highly expressed and contributes to clonogenicity in acute promyelocytic leukemia cells.

Stathmin 1 (STMN1) is a microtubule-destabilizing protein highly expressed in hematological malignancies and involved in proliferation and differentiation. Although a previous study found that the PML-RARα fusion protein, which contributes to the pathophysiology of acute promyelocytic leukemia (APL), positively regulates STMN1 at the transcription and protein activity levels, little is known about the role of STMN1 in APL. In this study, we aimed to investigate the STMN1 expression levels and their associations with laboratory, clinical, and genomic data in APL patients. We also assessed the dynamics of STMN1 expression during myeloid cell differentiation and cell cycle progression, and the cellular effects of STMN1 silencing and pharmacological effects of microtubule-stabilizing drugs on APL cells. We found that STMN1 transcripts were significantly increased in samples from APL patients compared with those of healthy donors (all p < 0.05). However, this had no effect on clinical outcomes. STMN1 expression was associated with proliferation- and metabolism-related gene signatures in APL. Our data confirmed that STMN1 was highly expressed in early hematopoietic progenitors and reduced during cell differentiation, including the ATRA-induced granulocytic differentiation model. STMN1 phosphorylation was predominant in a pool of mitosis-enriched APL cells. In NB4 and NB4-R2 cells, STMN1 knockdown decreased autonomous cell growth (all p < 0.05) but did not impact ATRA-induced apoptosis and differentiation. Finally, treatment with paclitaxel (as a single agent or combined with ATRA) induced microtubule stabilization, resulting in mitotic catastrophe with repercussions for cell viability, even in ATRA-resistant APL cells. This study provides new insights into the STMN1 functions and microtubule dynamics in APL.

Reduced SLIT2 is Associated with Increased Cell Proliferation and Arsenic Trioxide Resistance in Acute Promyelocytic Leukemia.

The SLIT-ROBO axis plays an important role in normal stem-cell biology, with possible repercussions on cancer stem cell emergence. Although the Promyelocytic Leukemia (PML) protein can regulate SLIT2 expression in the central nervous system, little is known about SLIT2 in acute promyelocytic leukemia. Hence, we aimed to investigate the levels of SLIT2 in acute promyelocytic leukemia (APL) and assess its biological activity in vitro and in vivo. Our analysis indicated that blasts with SLIT2high transcript levels were associated with cell cycle arrest, while SLIT2low APL blasts displayed a more stem-cell like phenotype. In a retrospective analysis using a cohort of patients treated with all-trans retinoic acid (ATRA) and anthracyclines, high SLIT2 expression was correlated with reduced leukocyte count (p = 0.024), and independently associated with improved overall survival (hazard ratio: 0.94; 95% confidence interval: 0.92-0.97; p < 0.001). Functionally, SLIT2-knockdown in primary APL blasts and cell lines led to increased cell proliferation and resistance to arsenic trioxide induced apoptosis. Finally, in vivo transplant of Slit2-silenced primary APL blasts promoted increased leukocyte count (p = 0.001) and decreased overall survival (p = 0.002) compared with the control. In summary, our data highlight the tumor suppressive function of SLIT2 in APL and its deteriorating effects on disease progression when downregulated.

NTAL is associated with treatment outcome, cell proliferation and differentiation in acute promyelocytic leukemia.

Non-T cell activation linker (NTAL) is a lipid raft-membrane protein expressed by normal and leukemic cells and involved in cell signaling. In acute promyelocytic leukemia (APL), NTAL depletion from lipid rafts decreases cell viability through regulation of the Akt/PI3K pathway. The role of NTAL in APL cell processes, and its association with clinical outcome, has not, however, been established. Here, we show that reduced levels of NTAL were associated with increased all-trans retinoic acid (ATRA)-induced differentiation, generation of reactive oxygen species, and mitochondrial dysfunction. Additionally, NTAL-knockdown (NTAL-KD) in APL cell lines led to activation of Ras, inhibition of Akt/mTOR pathways, and increased expression of autophagy markers, leading to an increased apoptosis rate following arsenic trioxide treatment. Furthermore, NTAL-KD in NB4 cells decreased the tumor burden in (NOD scid gamma) NSG mice, suggesting its implication in tumor growth. A retrospective analysis of NTAL expression in a cohort of patients treated with ATRA and anthracyclines, revealed that NTAL overexpression was associated with a high leukocyte count (P = 0.007) and was independently associated with shorter overall survival (Hazard Ratio: 3.6; 95% Confidence Interval: 1.17-11.28; P = 0.026). Taken together, our data highlights the importance of NTAL in APL cell survival and response to treatment.

Acute promyelocytic leukemia: evaluation of diagnostic tests from 2000 to 2018 in a public hospital / Leucemia promielocítica aguda: avaliação dos testes diagnósticos entre o período de 2000 e 2018 em um hospital público

ABSTRACT Introduction: Acute promyelocytic leukemia (APL) is caused by t(15;17)(q24;q21) translocation, which product is the fusion oncoprotein PML-RARa (promyelocytic leukemia-retinoic acid receptor alpha). The morphology of leukemic promyelocytes is usually characteristic, with the presence of faggot cells and coarse cytoplasmic granulations; immunophenotype is characteristic in most cases. However, definitive laboratory diagnosis should be performed by detecting t(15;17) or by PML-RARa fusion protein. Objectives: To compare cytomorphology, flow cytometry, and classical cytogenetic of bone marrow samples from patients with APL, treated at the Complexo Hospital de Clínicas da Universidade Federal do Paraná (CHC-UFPR), as well as describe the possible discrepancies between the methodologies. Method: Retrospective analysis of APL cases treated at the CHC-UFPR from January 2000 to July 2018. Results: Eighty-eight patients (42 man/ 46 woman; mean age: 34 years), 42.1% of them presented a high-risk prognosis. Flow cytometry was performed in 83 cases (94.3%); karyotype was performed in 79 cases (89.7%), but translocation t(15;17) was confirmed in only 53 cases (60.2%). From the 28 patients with a non-conclusive karyotype; fourteen (15.9%) of them presented the PML-RARa transcript in the molecular analysis. In total, 35 patients (39 8%) performed research of the PML-RARa gene by molecular biology. Only 45 patients (51.1%) presented concordant diagnosis among the three technical exams (morphology, flow cytometry and cytogenetics). Overall survival was 67% at 4.8 years, with 29 deaths. Conclusion: Genetic confirmation was observed in 76.1% of samples, 60.2% by conventional cytogenetics and 15.9% by molecular biology. There was a disagreement between the methodologies, and a low sensibility of the conventional cytogenetics, demonstrating the importance of performing molecular techniques for diagnostic confirmation.

RESUMEN Introducción: La leucemia promielocítica aguda (LPA) es causada por la translocación t(15;17)(q24;q21), cuyo producto es la oncoproteína de fusión PML-RARa (proteína de la leucemia promielocítica-receptor alfa de ácido retinoico). La morfología de los promielocitos leucémicos suele ser típica, con presencia de células faggot (células en haces) y gruesasgranulaciones citoplásmicas; el inmunofenotipo es característico en la mayor parte de los casos. No obstante, el diagnóstico final de laboratorio debe ser hecho por la detección de la t(15;17) o por la oncoproteína PML-RARa. Objetivos: Comparar la citomorfología, la citometría de flujo y la citogenética clásica de muestras de médula ósea de pacientes con LPA asistidos en el Complexo Hospital de Clínicas da Universidade Federal do Paraná (CHC-UFPR), así como describir lasposibles discrepancias entre los métodos. Método: Análisis retrospectivo de los casos de LPA asistidos en el CHC-UFPR entre enero de 2000 y julio de 2018. Resultados: De los 88 pacientes (42 hombres y 46 mujeres; edad promedio: 34 anos), 42,1% presentaron pronóstico de alto riesgo. Citometría de flujo se realizó en 83 casos (94,3%); cariotipo en 79 casos (89,7%),pero la translocación se confirmó en sólo53 (60,2%) casos. Entre los28 pacientes con cariotipo no concluyente, 14 (15,9%) presentaron el transcripto PML-RARa. En total, 35 pacientes (39,8%) realizaron la pesquisa del gen PML-RARa por biología molecular. Cuarenta y cinco pacientes (51,1%) tuvieron diagnóstico acorde entre los métodos (morfología, citometría de flujo y citogenética). La supervivencia global fue de 67% en 4,8 anos, con 29 muertes. Conclusión: Hubo confirmación genética en 76,1% de las muestras, siendo 60,2% por citogenética y 15,9%por biología celular. Hubo desacuerdo entre los métodos y baja sensibilidad de la citogenética convencional, lo que demuestra la importancia de la realización de técnicas moleculares para confirmación diagnóstica.

RESUMO Introdução: A leucemia promielocítica aguda (LPA) écausada pela translocação t(15;17)(q24;q21), cujo produto éa oncoproteína de fusão PML-RARa (leucemia promielocítica-receptor alfa do ácido retinoico). A morfologia dos promielócitos leucêmicos é habitualmente característica, com presença de faggot cells (células em maços ou feixes) e granulações citoplasmáticas grosseiras; o imunofenótipo é característico na maioria dos casos. Porém, o diagnóstico laboratorial definitivo deve ser feito pela detecção da t(15;17) ou pela oncoproteína PML-RARa. Objetivos: Comparar a citomorfologia, a citometria de fluxo e a citogenética clássica de amostras de medula óssea de pacientes com LPA atendidos no Complexo Hospital de Clínicas da Universidade Federal do Paraná (CHC-UFPR), bem como descrever as possíveis discrepâncias entre as metodologias. Método: Análise retrospectiva dos casos de LPA atendidos no CHC-UFPR entre janeiro de 2000 e julho de 2018. Resultados: Dos 88 pacientes (42 homens e 46 mulheres; média de idade: 34 anos), 42,1% apresentaram prognóstico de alto risco. A citometria de fluxo foi realizada em 83 casos (94,3%); o cariótipo, em 79 casos (89,7%), mas a translocação foi confirmada em apenas 53 (60,2%) casos. Dos 28 pacientes com cariótipo não conclusivo, 14 (15,9%) tinham a presença do transcrito PML-RARa. No total, 35 pacientes (39,8%) realizaram a pesquisa do gene PML-RARa por biologia molecular. Quarenta e cinco pacientes (51,1%) obtiveram diagnóstico concordante entre as metodologias (morfologia, citometria de fluxo e citogenética). A sobrevida global foi de 67% em 4,8 anos;com 29 óbitos. Conclusão: A confirmação genética foi realizada em 76,1% das amostras, sendo 60,2%por citogenética e 15,9% por biologia molecular. Houve discordância entre as metodologias e baixa sensibilidade da citogenética convencional, o que demonstra a importância da realização de técnicas moleculares para confirmação diagnóstica.

Combining gene mutation with gene expression analysis improves outcome prediction in acute promyelocytic leukemia.

By combining the analysis of mutations with aberrant expression of genes previously related to poorer prognosis in both acute promyelocytic leukemia (APL) and acute myeloid leukemia, we arrived at an integrative score in APL (ISAPL) and demonstrated its relationship with clinical outcomes of patients treated with all-trans retinoic acid (ATRA) in combination with anthracycline-based chemotherapy. Based on fms-like tyrosine kinase-3-internal tandem duplication mutational status; the ΔNp73/TAp73 expression ratio; and ID1, BAALC, ERG, and KMT2E gene expression levels, we modeled ISAPL in 159 patients (median ISAPL score, 3; range, 0-10). ISAPL modeling identified 2 distinct groups of patients, with significant differences in early mortality (P < .001), remission (P = .004), overall survival (P < .001), cumulative incidence of relapse (P = .028), disease-free survival (P = .03), and event-free survival (P < .001). These data were internally validated by using a bootstrap resampling procedure. At least for patients treated with ATRA and anthracycline-based chemotherapy, ISAPL modeling may identify those who need to be treated differently to maximize their chances for a cure.

Brazilian workshop model to train investigators in chronic graft-versus-host disease clinical trials according to the 2005-2006 National Institutes of Health recommendations

BACKGROUND: The lack of standardization of clinical diagnostic criteria, classification and severity scores of chronic graft-versus-host disease led the National Institutes of Health to propose consensus criteria for the purpose of clinical trials. METHODS: Here we describe a one-day workshop model conducted by the Chronic Graft-versus-Host Disease Brazil-Seattle Consortium Study Group to train investigators interested in participating in multicenter clinical trials in Brazil. Workshop participants included eight transplant physicians, one dermatologist, two dentists, three physical therapists and one psychologist from five institutions. Workshop participants evaluated nine patients with varying degrees of severity of mucocutaneous lesions and other manifestations of the disease followed by a training session to review and discuss the issues encountered with the evaluation and scoring of patients and in the methods used to evaluate grip strength and the 2-minute walk test. RESULTS: Most participants had difficulties in rating the percentage of each type of mucocutaneous lesion and thought 20 minutes was insufficient to evaluate and record the scores of each patient using the National Institutes of Health criteria and other cutaneous assessments. Several specific areas of difficulties encountered by the evaluators were: 1) determining the percentage of erythema in movable and non-movable sclerosis, 2) whether to score all cutaneous findings in a particular area or just the dominant lesion; 3) clarification of the definition of poikiloderma in chronic graft-versus-host disease; 4) discrepant interpretation of the mouth score and 5) clarification on the methodology used for the evaluation of grip strength and the 2-minute walk tests. CONCLUSIONS: Results of this workshop support the need to train investigators participating in clinical trials on chronic graft-versus-host disease.

Brazilian workshop model to train investigators in chronic graft-versus-host disease clinical trials according to the 2005-2006 National Institutes of Health recommendations.

BACKGROUND: The lack of standardization of clinical diagnostic criteria, classification and severity scores of chronic graft-versus-host disease led the National Institutes of Health to propose consensus criteria for the purpose of clinical trials. METHOD: Here we describe a one-day workshop model conducted by the Chronic Graft-versus-Host Disease Brazil-Seattle Consortium Study Group to train investigators interested in participating in multicenter clinical trials in Brazil. Workshop participants included eight transplant physicians, one dermatologist, two dentists, three physical therapists and one psychologist from five institutions. Workshop participants evaluated nine patients with varying degrees of severity of mucocutaneous lesions and other manifestations of the disease followed by a training session to review and discuss the issues encountered with the evaluation and scoring of patients and in the methods used to evaluate grip strength and the 2-minute walk test. RESULTS: Most participants had difficulties in rating the percentage of each type of mucocutaneous lesion and thought 20 minutes was insufficient to evaluate and record the scores of each patient using the National Institutes of Health criteria and other cutaneous assessments. Several specific areas of difficulties encountered by the evaluators were: 1) determining the percentage of erythema in movable and non-movable sclerosis, 2) whether to score all cutaneous findings in a particular area or just the dominant lesion; 3) clarification of the definition of poikiloderma in chronic graft-versus-host disease; 4) discrepant interpretation of the mouth score and 5) clarification on the methodology used for the evaluation of grip strength and the 2-minute walk tests. CONCLUSIONS: Results of this workshop support the need to train investigators participating in clinical trials on chronic graft-versus-host disease.

A multicenter feasibility study of chronic graft-versus-host disease according to the National Institute of Health criteria: efforts to establish a Brazil-Seattle consortium as a platform for future collaboration in clinical trials.

BACKGROUND: New criteria for the diagnosis and classification of chronic graft-versus-host disease were developed in 2005 for the purpose of clinical trials with a consensus sponsored by the National Institute of Health. OBJECTIVES: The aim of this study is to present the results of a multicenter pilot study performed by the Brazil-Seattle chronic graft-versus-host disease consortium to determine the feasibility of using these criteria in five Brazilian centers. METHODS: The study was performed after translation of the consensus criteria into Portuguese and training. A total of 34 patients with National Institute of Health chronic graft-versus-host disease were enrolled in the pilot study between June 2006 and May 2009. RESULTS: Of the 34 patients, 26 (76%) met the criteria of overlap syndrome and eight (24%) the classic subcategory. The overall severity of disease was moderate in 21 (62%) and severe in 13 (38%) patients. The median time from transplant to onset of chronic graft-versus-host disease was 5.9 months (Range: 3 - 16 months); the median time for the overlap syndrome subcategory was 5.9 months (Range: 3 - 10 months) and for the classic subcategory, it was 7.3 months (Range: 3 - 16 months). At a median follow up of 16.5 months (Range: 4 - 39 months), overall survival was 75%. CONCLUSIONS: It was feasible to use the National Institute of Health consensus criteria for the diagnosis and scoring of chronic graft-versus-host disease in a Brazilian prospective multicenter study. More importantly, a collaborative hematopoietic cell transplantation network was established in Brazil offering new opportunities for future clinical trials in chronic graft-versus-host disease and in other areas of research involving hematopoietic stem cell transplantation.

A multicenter feasibility study of chronic graft-versus-host disease according to the National Institute of Health criteria: efforts to establish a Brazil-Seattle consortium as a platform for future collaboration in clinical trials

BACKGROUND: New criteria for the diagnosis and classification of chronic graft-versus-host disease were developed in 2005 for the purpose of clinical trials with a consensus sponsored by the National Institute of Health. OBJECTIVES: The aim of this study is to present the results of a multicenter pilot study performed by the Brazil-Seattle chronic graft-versus-host disease consortium to determine the feasibility of using these criteria in five Brazilian centers. METHODS: The study was performed after translation of the consensus criteria into Portuguese and training. A total of 34 patients with National Institute of Health chronic graft-versus-host disease were enrolled in the pilot study between June 2006 and May 2009. RESULTS: Of the 34 patients, 26 (76 percent) met the criteria of overlap syndrome and eight (24 percent) the classic subcategory. The overall severity of disease was moderate in 21 (62 percent) and severe in 13 (38 percent) patients. The median time from transplant to onset of chronic graft-versus-host disease was 5.9 months (Range: 3 - 16 months); the median time for the overlap syndrome subcategory was 5.9 months (Range: 3 - 10 months) and for the classic subcategory, it was 7.3 months (Range: 3 - 16 months). At a median follow up of 16.5 months (Range: 4 - 39 months), overall survival was 75 percent. CONCLUSIONS: It was feasible to use the National Institute of Health consensus criteria for the diagnosis and scoring of chronic graft-versus-host disease in a Brazilian prospective multicenter study. More importantly, a collaborative hematopoietic cell transplantation network was established in Brazil offering new opportunities for future clinical trials in chronic graft-versus-host disease and in other areas of research involving hematopoietic stem cell transplantation.

Transplante de células-tronco hematopoéticas em crianças e adolescentes com leucemia aguda: experiência de duas instituições brasileiras / Hematopoietic stem cell transplantation in children and adolescents with acute leukemia: experience of two Brazilian institutions

O transplante de células-tronco hematopoéticas (TCTH) é o tratamento de escolha para leucemias agudas de alto risco. Apesar da melhora na sobrevida destes pacientes, a recidiva continua sendo a maior causa de óbito pós-transplante de células-tronco hematopoéticas. O objetivo deste trabalho foi analisar os resultados dos transplantes realizados em crianças com leucemia aguda em duas instituições brasileiras. Realizou-se estudo retrospectivo de 208 pacientes transplantados entre 1990-2007. Mediana de idade: 9 anos; 119 pacientes com leucemia linfoide aguda (LLA) e 89 com leucemia mieloide aguda (LMA). Doença precoce: CR1 e CR2. ... 14/195 pacientes tiveram falha primária de pega (8 por cento). Não houve diferença na sobrevida global e sobrevida livre de recaída entre pacientes com leucemia linfoide aguda e leucemia mieloide aguda, entre transplantes aparentados e não aparentados, tampouco entre as fontes de células utilizadas. O desenvolvimento da doença do enxerto contra hospedeiro (DECH) aguda ou crônica também não influenciou a sobrevida global e sobrevida livre de recaída. Pacientes com leucemia linfoide aguda condicionados com irradiação corporal total (TBI) apresentaram melhor sobrevida global e sobrevida livre de recaída (p<0,001). Cento e dezoito pacientes morreram entre 1-1.654 dias pós-transplante de células-tronco hematopoéticas (M:160). Mortalidade relacionada a transplante (MRT) (dia+100): 16 por cento. Incidência cumulativa de recaída: 40 por cento (3 anos). Pacientes com doença avançada tiveram menor sobrevida global e sobrevida livre de recaída (três anos)(p<0,001). Na análise multivariada, o status da doença foi o principal fator associado ao aumento da sobrevida global e sobrevida livre de recaída. Nossos resultados mostram que é possível se atingir uma boa sobrevida para pacientes com doença precoce e também mostram a baixa eficácia naqueles com doença avançada.

Hematopoietic Stem Cell transplantation (HSCT) is the treatment of choice for patients with high-risk leukemia. In spite of this, relapse remains a major cause of death of these patients. Our objective was to analyze the outcomes of patients with acute leukemia submitted to hematopoietic stem cell transplantation in two Brazilian institutions... There were no differences in the overall survival and event free survival between patients with acute lymphocytic leukemia and acute myeloid leukemia, between sources of cells used or between those who developed acute or chronic graft-versus-host disease (GVHD). When comparing transplants from related and unrelated donors, there was no difference in the overall survival. Patients with acute lymphocytic leukemia receiving the total body irradiation (TBI) conditioning regimen had better overall survival and event free survival (p<0.001). One hundred and eighteen patients died between 0 and 1654 days after hematopoietic stem cell transplantation (M: 160 days). Transplantation-related-mortality (TRM) at D+100 was 16 percent and cumulative incidence of relapse was 40 percent (3 years). Patients with advanced disease had lower 3-year overall survival and event free survival (p<0.001). Multivariate analysis showed that disease status was the most significant factor associated with higher event free survival and overall survival . Our results show that children and adolescents transplanted with early disease can achieve considerable overall survival and also highlights the inefficacy of hematopoietic stem cell transplantation for patients with advanced disease.