Clinical networking results in continuous improvement of the outcome of patients with acute promyelocytic leukemia.

ABSTRACT: The introduction of all-trans retinoic acid combined with anthracyclines has significantly improved the outcomes for patients diagnosed with acute promyelocytic leukemia (APL), and this strategy remains the standard of care in countries in which arsenic trioxide is not affordable. However, data from national registries and real-world databases indicate that low- and middle-income countries (LMIC) still face disappointing results, mainly because of high induction mortality and suboptimal management of complications. The American Society of Hematology established the International Consortium on Acute Leukemias (ICAL) to address this challenge through international clinical networking. Here, we present the findings from the International Consortium on Acute Promyelocytic Leukemia study involving 806 patients with APL recruited from 2005 to 2020 in Brazil, Chile, Paraguay, Peru, and Uruguay. The induction mortality rate has notably decreased to 14.6% compared with the pre-ICAL rate of 32%. Multivariable logistic regression analysis revealed as factors associated with induction death: age of ≥40 years, Eastern Cooperative Oncology Group performance status score of 3, high-risk status based on the Programa Español de Tratamiento en Hematologia/Gruppo Italiano Malattie EMatologiche dell'Adulto classification, albumin level of ≤3.5 g/dL, bcr3 PML/RARA isoform, the interval between presenting symptoms to diagnosis exceeding 48 hours, and the occurrence of central nervous system and pulmonary bleeding. With a median follow-up of 53 months, the estimated 4-year overall survival rate is 81%, the 4-year disease-free survival rate is 80%, and the 4-year cumulative incidence of relapse rate is 15%. These results parallel those observed in studies conducted in high-income countries, highlighting the long-term effectiveness of developing clinical networks to improve clinical care and infrastructure in LMIC.

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.

Transplante de células-tronco hematopoéticas em linfoma Hodgkin / Stem cell transplantation in Hodgkin lymphoma

O linfoma Hodgkin(LH) é uma malignidade hematológica que conta com um armamentário terapêutico selecionado de acordo com o estadiamento e a classificação prognóstica de cada doente. A sobrevida dos pacientes tratados para o LH clássico vem aumentando significativamente, com taxas de cura entre 80 por cento-85 por cento. Entretanto, 20 por cento-25 por cento são refratários aos tratamentos iniciais e cerca de 30 por cento recaem após ter alcançado resposta completa. Os pacientes considerados com falha à terapia de primeira linha ainda têm uma segunda chance de cura se apresentarem quimiossensibilidade aos esquemas de salvamento, seguido por uma das modalidades de transplante de células-tronco hematopoéticas (TCTH). O TCTH autólogo representa uma estratégia atrativa para os pacientes com LH que falham ao tratamento convencional de primeira linha. Os resultados em termos de sobrevidas livre de doença e global são superiores aos esquemas de salvamento com quimioterapia convencional. Este procedimento tem finalidade curativa para 50 por cento dos pacientes em segunda remissão quimiossensíveis e pode levar a remissões duráveis naqueles com mais de duas linhas de terapia. Atualmente, o TCTH alogênico, basicamente com condicionamento de intensidade reduzida (RIC), está indicado em pacientes com recaída precoce após o TCTH autólogo ou em pacientes bastante jovens com refratariedade a mais de duas linhas de tratamento convencional.

Hodgkin's Lymphoma is a hematologic malignancy with a wide range of therapeutic options that must be chosen according to the stage and the prognostic classification of each patient. The overall survival of patients treated for classic Hodgkin's Lymphoma is increasing significantly, with current cure rates being between 80 percent and 85 percent. Nevertheless, 20 percent to 25 percent are refractory to the initial treatment and about 30 percent relapse after having reached a complete response. Patients that have failed standard therapy still have a second chance of cure if they present chemosensitivity to cure schemes, followed by one type of hematopoietic stem cell transplantation (TCTH). Autologous TCTH is an attractive strategy for Hodgkin's Lymphoma patients that fail in the conventional standard therapy. The results in terms of overall survival and disease-free survival are higher than the cure schemes with conventional chemotherapy. This procedure addresses the cure in 50 percent of chemosensitive patients in second remission, and can lead to lasting remissions for those with more than two lines of treatment. Today, allogeneic TCTH, basically with reduced intensity conditioning (RIC) is indicated for patients with premature relapse after autologous TCTH or for young patients refractory to one or more lines of conventional treatment.

Trombocitose essencial: o que é essencial saber / Essential thrombocytosis: what is vital to know

A trombocitose essencial (TE) faz parte do grupo de síndromes mieloproliferativas (SMP) cromossomo Philadelphia(Ph) negativas. Caracteriza-se pela hiperproliferação megacariocítica com consequente trombocitose periférica, favorecendo fenômenos trombo-hemorrágicos. Esta entidade estava esquecida até meados de 2005, quando as recentes publicações sobre as alterações moleculares na atividade da enzima tirosina quinase, JAK2, desencadeou um novo interesse sobre a patogenia, aspectos clínicos e terapêuticos da TE. A identificação das mutações de JAK2 e do gene MPL W515K, W515L e S505N impulsionou a nova proposta da Organização Mundial de Saúde (OMS) para reformular os critérios diagnósticos, reduzindo o número de plaquetas para 450x10(9)/L. O alicerce do tratamento são agentes redutores das contagens plaquetárias: hidroxiureia, anagrelide ou interferon associados à prevenção das complicações trombo-hemorrágicas. Não há um tratamento curativo para a TE, mas despontam perspectivas de que terapias alvo, bloqueadoras da mutação JAK2, possam incrementar o desfecho da doença. Inibidores de JAK2, específicos e inespecíficos, estão sendo estudados em fase I e II e parecem promissores num futuro próximo.

Essential thrombocythemia (ET) is an acquired myeloproliferative Philadelphia negative disorder characterized by megakaryocytic hyperproliferation and persistent peripheral thrombocytosis with a tendency of thrombosis and hemorrhages. This entity was forgotten until 2005, when the recent identification of somatic mutations such as JAK2V617F and MPL W515L/K triggered off interest in the molecular pathogenesis, clinical aspects and therapeutic approach of ET. The presence of molecular mutations changed the diagnostic criteria proposed by the World Health Organization, and nowadays the platelet count for which ET should be considered has dropped to 450 X 10(9) /L. Treatment is given according to risk stratification: in cases with high risk platelet reduction, therapy using drugs such as hydroxyurea, interferon or anagrelide is chosen. There is no drug known to cure ET and the current therapy is either to prevent thrombohemorrhagic events or reductions in the platelet count. The identification of the JAK2V617F mutation has opened an opportunity to develop new therapeutic target. JAK2 inhibitors are promising for the treatment of ET in the near future.

Leucemia mielóide aguda: o olhar dos anos 2000 no Serviço de Hematologia do Hospital de Clínicas de Porto Alegre-RS / Acute myeloid leukemia from the year 2000 point of view Hematology Service - Hospital de Clínicas de Porto Alegre-RS

A leucemia mielóide aguda (LMA) representa uma preocupação para os especialistas, porque perfaz um percentual alto das leucemias no adulto e o sucesso terapêutico ainda é insatisfatório. A partir do ano 2000, o Serviço de Hematologia do Hospital de Clínicas de Porto Alegre definiu estratégias para diagnóstico, tratamento e seguimento das LMAs, de acordo com o subtipo FAB, idade, citogenética e performance status (ECOG). Todos os casos de LMA "de novo"não promielocítica, em adultos (15 a 65 anos) foram acompanhados prospectivamente, desde outubro de 2001, data da implantação do protocolo c,ompreendendo três fases de tratamento: indução com o tradicional "7+3", citarabina 100 mg/m²/dia em infusão contínua em 7d, e daunorrubicina 60 mg/m²/dia em 3d e citarabina intratecal no D1 nas LMA M4 e M5. Após a recuperação medular, segue a consolidação idêntica à indução e posteriormente a intensificação com dois ou três ciclos de altas doses de citarabina 6 g/m²/dia por três dias. Foram diagnosticados, entre outubro/01 e dezembro/05, 69 pacientes portadores de LMA e destes, 39 com LMA "de novo"e idade entre 15 e 65 anos. Neste grupo foram analisadas a taxa de remissão, a taxa de recaída, a refratariedade e o tempo de sobrevida global. No final da observação foram encontrados: a taxa de indução de remissão 75 por cento; aconteceram 12 (40 por cento) recaídas, 7 (19 por cento) foram refratários ao tratamento. A sobrevida global foi 37 por cento em 56 meses, representando um incremento aos resultados obtidos no Serviço na década passada.

Acute myeloid leukemia (AML) is still a concern for hematologists as it represents a significant percentage of adult leukemias and the therapeutic success rates are unsatisfactory. In 2000, the Hematology Department of Hospital de Clínicas de Porto Alegre defined strategies for the diagnosis, treatment and follow up of AML patients according to the FAB subtype classification, age, cytogenetic tests and performance status (ECOG). Patients with promyelocytic leukemia are treated using the AIDA (GIMEMA) protocol with those older than 65 years receiving palliative therapy using hydroxyurea, oral etoposide, thalidomide, subcutaneous cytarabine or an association of drugs. Since October 2001 all our "de novo"AML patients aged 15 to 65 years with non-promyelocytic acute leukemia were prospectively followed up. At diagnosis we start a three phase treatment protocol: induction with a classical "7+3"therapy regimen, that is continuous infusion of 100 mg/m²/day cytarabine for 7 days, 60 mg/m²/day daunorubicin for 3 days and on day 1 an intrathecal cytarabine in AML M4 and M5 cases. After bone marrow recovery, if complete remission is achieved, follow ups involve an identical "7+3"consolidation phase followed by two or three high dose cycles of 6 g/m²/day cytarabine for 3 days. A group of 39 patients diagnosed between October 2001 and December 2005 was followed up until June 2006. Our objectives were to evaluate the effectiveness of the protocol for remission, relapse rates and overall survival. The rate of complete remission was 75 percent. Relapse occurred in 12/29 (40 percent) patients and the overall survival rate at 56 months was 37 percent, showing an improvement on our results of previous decades.

Alta frequência de fatores de alto risco e de mortalidade precoce em pacientes brasileiros com leucemia promielocítica aguda / Increased frequency of high risk factors and elevated early mortality among Brazilian patients with acute promyelocytic leukemia

O tratamento da leucemia promielocítica aguda (LPA) com antrciclínicos e ácido trans-retinóico (ATRA) tem sido amplamente empregado e resultou em taxas de sobrevida a longo prazo de 80% a 90% em diferentes ensaios clínicos. A despeito da alta prevalência de LPA na América Latina, a efetividade de regimes de tratamento com ATRA e antraciclínicos não é conhecida. No Brasil, mais de 20% das leucemias mielóides agudas são do subtipo LPA. Neste estudo descrevemos uma análise retrospectiva de 157 pacientes brasileiros com LPA. Comparado com pacientes de países desenvolvidos, observamos uma alta prevalência de pacientes de alto risco e ma sobrevida e três anos de 49,9%. A taxa de mortalidade precoce foi de 28%, principalmente devido a sangramento (88,6%), com 45,2% dos pacientes apresentando evidências laboratoriais de coagulação intravascular disseminada ao diagnóstio. A despeito do fato de que nõ foram excluídos pacientes com base na idade ou no performance status, esta alta taxa de óbito mostra que é necessária uma melhora urgente no acesso dos pacientes a centros médicos especializados.

Therapy based on anthracyclines and all-trans-retinoic acid (ATRA) hás been widely used for acute promyelocytic leukemia (APL) and result in long term survival rates of 80% to 90% in different clinical trials. Despite the higher incidence of APL in Latin America, the effectiveness of ATRA + anthracyclines treatment is not known. In Brazil, more than 20% of acute myeloid leukemia are of the APL subtype. We describe a retrospective analysis including 157 Brazilian APL patients. Compared to developed countries, a higher incidence of higher incidence of high risk patients was observed and the overwall survival in three years was only 49.9%. Early mortality was 28%, mainly due to bleeding (88.6%), and laboratorial evidence of disseminated intravascular coagulation at diagnosis was present in 45.2% of the patients. Despite the fact that no patient was excluded based on age and performance status, the high death rates shows that urgent improvement in acess to specialized medical care is necessary in Brazil. Aiming to improve the outcome of APL patients in developing countries, the American Society of Hematology launched the International Consortium on APL, an educational iniative based on the use of an unified simplified treatment protocol, on line discussion tools and centralized laboratory diagnosis.