Guidelines on the diagnosis and treatment for acute promyelocytic leukemia: Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular Guidelines Project: Associação Médica Brasileira - 2013

Diagnosis and management of acute promyelocytic leukemia: Brazilian consensus guidelines 2024 on behalf of the Brazilian Association of Hematology, Hemotherapy and Cellular Therapy

Improvements in clinical assessment have occurred since the last published recommendations on the diagnosis and treatment of acute promyelocytic leukemia in 2013. Here, a committee of specialists of the Brazilian Association of Hematology, Hemotherapy and Cellular Therapy presents a comprehensive review on the current knowledge, focusing on the advances in diagnosis, risk assessment, and frontline and salvage therapy. The concept of urgent diagnosis is explored as well as the management of critical situations such as coagulopathy and differentiation syndrome. Recent adjustments in risk stratification based on white blood cell counts only are presented together with the incorporation of chemo-free regimens for non-high-risk patients. Special conditions such as acute promyelocytic leukemia in children, the elderly and pregnant women are discussed. Finally, acute promyelocytic leukemia is presented as a highly curable disease because of the real possibility of targeted therapy towards differentiation, and, paradoxically, as a serious and urgent condition that deserves prompt recognition and management to avoid early mortality.

Improvement of Early Death in Acute Promyelocytic Leukemia: A Population-Based Analysis

BACKGROUND

Early death is a major factor of treatment failure in acute promyelocytic leukemia (APL), however, the recent trends in the incidence of early death based on the population-level are not clear. Hence, this study is aimed at describing the incidence, recent trends, causes and characteristics of early death in APL based on the real world.

MATERIALS AND METHODS

APL patients diagnosed from 1986 to 2015 in the Surveillance, Epidemiology, and End Results (SEER) dataset were enrolled, and categorized based on gender, age, year of diagnosis, race, marital status, resident county and socioeconomic status (SES). The risk factors for all-cause and acute myelocytic leukemia (AML) specific early death were determined by univariate and multivariate logistic regression analyses, and stratified analysis was conducted by age.

RESULTS

Overall, 3212 APL patients were included in analysis between 1986 and 2015, of which a total of 683 (21.3%) patients were noted for early death. Significant differences were recognized for patient distribution by age, year of diagnosis, marital status, and SES. The early death rate of APL patients diagnosed during 2006-2015 was significantly lower than that of the early stage, but this trend was not evident in juvenile patients. At the same time, older age, and lower SES score were independent risk factors for early death in the multivariate analysis.

CONCLUSION

We established that the early death trend in APL has decreased over the past few years, but the early death rate remains high, especially in older patients and those with lower SES.

Pediatric Acute Promyelocytic Leukemia: Epidemiology, Molecular Features, and Importance of GST-Theta 1 in Chemotherapy Response and Outcome

Previous studies have suggested a variation in the incidence of acute promyelocytic leukemia (APL) among the geographic regions with relatively higher percentages in the Latin American population. We aimed to explore the population burden of pediatric APL, gathering information from the population-based cancer registry (PBCR) and the diagnosis of APL obtained through incident cases from a hospital-based cohort. The homozygous deletion in glutathione S-transferases (GSTs) leads to a loss of enzyme detoxification activity, possibly affecting the treatment response. Mutations in the RAS pathway genes are also considered to be a key component of the disease both in the pathogenesis and in the outcomes. We have assessed mutations in a RAS-MAP kinase pathway (FLT3, PTPN11, and K-/NRAS) and GST variant predisposition risk in the outcome. Out of the 805 children and adolescents with acute myeloid leukemia (AML) who are registered in the PBCR, 35 (4.3%) were APL cases. The age-adjusted incidence rate (AAIR) was 0.03 per 100,000 person-years. One-hundred and sixty-three patients with APL were studied out of 931 AML cases (17.5%) from a hospital-based cohort. Mutations in FLT3, KRAS, and NRAS accounted for 52.1% of the cases. Patients with APL presented a 5-year probability of the overall survival (OS) of 67.3 ± 5.8%. A GST-theta 1 (GSTT1) null genotype conferred adverse prognosis, with an estimated hazard ratio of 2.8, 95% confidence interval (CI) 1.2-6.9. We speculate that the GSTT1 polymorphism is associated with therapeutics and would allow better OS of patients with APL with a GSTT1 null genotype.

Two successful deliveries of healthy children by a young woman diagnosed and treated during induction and relapsed therapy for acute promyelocytic leukemia

INTRODUCTION

Acute promyelocytic leukemia is an oncologic emergency. The limited cases reported in the literature have led to poor understanding of the safety of management of acute promyelocytic leukemia during pregnancy.

CASE REPORT

Herein is an acute promyelocytic leukemia case of a 22-year-old young pregnant woman who had various social problems. The patient was diagnosed with acute promyelocytic leukemia in her the second trimester of her first pregnancy.Management and outcome: She was treated with all-trans-retinoic acid with idarubicin and successfully delivered a healthy baby. She completed induction with idarubicin but defaulted her all-trans-retinoic acid, 6-mercaptopurine and methotrexate maintenance. She relapsed after one year and was salvaged with all-trans-retinoic acid high dose cytarabine and arsenic trioxide. She went into remission and had autologous stem cells collected and was planned for an autologous stem cell transplant but she defaulted. She relapsed when she was pregnant with her second baby during her third trimester (29+weeks) 10 months later. Salvage chemotherapy with arsenic trioxide, all-trans-retinoic acid and idarubicin was given. Patient underwent an emergency lower segment caesarian section at 31 weeks of pregnancy due to abnormal fetal cardiotocography. A healthy baby was delivered.

DISCUSSION

This drug regimen is controversial during pregnancy owing to the teratogenic effects and fatal retinoic acid syndrome especially in early gestation. In this case, patient was started the induction therapy of all-trans-retinoic acid treatment at her second trimester during her first pregnancy.

CONCLUSION

Our lady demonstrated the possibility of using all-trans-retinoic acid and arsenic trioxide and chemotherapy during second and third trimester with successful pregnancy outcomes.

Availability of all-trans retinoic acid and support systems for management of acute promyelocytic leukemia in Michigan and Louisiana, USA

Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia with high induction mortality in the general population despite evidence of high cure rates in the clinical trials. Aggressive supportive care is essential for ideal management of these patients. We conducted a survey to collect data on these important issues required for successful treatment/outcome of APL patients from two states (Michigan and Louisiana) due to their low one-year survival rate among the Surveillance, Epidemiology, and End Results registries. All eligible hospitals (253) were obtained from the Data Medicare online directory. Availability of ATRA, formulary process to obtain it, blood back availability and established treatment protocols for the management of APL patients were queried. Since most of the hospitals surveyed do not have a treatment protocol, we believe that outcome could be improved if a standardized and simplified set of treatment and supportive care guidelines are developed for all hospitals treating APL.

Early treatment of acute promyelocytic leukaemia is accurately guided by the PML protein localisation pattern: real-life experience from a tertiary New Zealand centre

Current guidelines recommend that a rapid test be used to assist diagnosis of acute promyelocytic leukaemia (APL), but the choice of an assay is discretionary. PML immunofluorescence (PML IF) identifies the microparticulate pattern of the PML protein localisation, highly specific for APL. The aim of this study was to evaluate clinical utility of PML IF in a real-life setting based on a retrospective records review for all patients who had PML IF performed in our centre between 2000 and 2017. Final analysis included 151 patients, 70 of whom had APL. PML IF was reported on average 3 days faster than cytogenetics. Compared with genetic results, PML IF showed sensitivity of 96% and specificity of 100%. PML IF accurately predicted APL in four APL cases with cryptic karyotype/FISH and excluded APL in 98% cases tested based on the suspicious immunophenotype alone, 21/28 of whom had mutated NPM1. Results of PML IF influenced decision to start ATRA in 25 (36%) APL patients and led to its termination in six non-APL patients. In conclusion, PML IF is a fast and reliable test that facilitates accurate treatment decisions when APL is suspected. This performance of PML IF remains hard to match in a real-life setting.

The global problem of early deaths in acute promyelocytic leukemia: A strategy to decrease induction mortality in the most curable leukemia

Acute promyelocytic leukemia (APL) is a hyper-acute illness and presents with profound cytopenias in most patients and disseminated intravascular coagulation (DIC). Excellent treatment options are now available with drugs such as all-trans retinoic acid (ATRA), arsenic trioxide (ATO), anthracyclines and cytarabine. The outcome in APL has improved tremendously in the last 50years due to better understanding of the disease, development of effective targeted agents and improvement in supportive care. Carefully selected groups of patients treated in large multi-center trials on a protocol and in experienced centers have shown survival rates in excess of 85%. However population data and other studies show that approximately 30% of patients die during induction. This is an Institutional, national and global problem and remains a pressing and frustrating challenge in APL. While most APL experts are aware of the high rate of early deaths (ED), such awareness is not typically present among general hematologists and oncologists. Our area of focus over the last 7years has been the reduction of ED in both academic and community centers; as a result we have acquired substantial experience in APL induction. Two centers have implemented population-wide prospective trials; Brazil and Georgia/South Carolina, USA with improvement in the ED rate. Both centers used standardized guidelines along with consultative support and sharing of expertise which proved effective and helped to decrease ED. Induction mortality in APL is 30% or greater. We believe ED is largely preventable and population-wide survival can be improved. An effective strategy is to utilize a set of simplified treatment guidelines coupled with support from a group of experts during induction. Treating oncologists in both academic and community hospitals should receive aggressive education about ED and be encouraged to seek advice from a core group of established APL experts. This model could be implemented nationally to improve population-wide survival in this most curable leukemia.

Treating acute promyelocytic leukaemia in Latin America: lessons from the International Consortium on Acute Leukaemia experience

The Latin Americas and Caribbean are regions where social exclusion and inequality persist as the main obstacles to human development and improvement of health conditions, despite economic growth and social development. These countries need to establish international collaborations with the goal of improving health conditions. In this scenario Acute Promyelocytic Leukaemia (APL), a disease with a high cure rate in developed countries and high prevalence in young patients, offers an ideal opportunity to implement measures with educational and cooperative scope. We discuss the experience of Latin America and the Caribbean through a common network, the International Consortium on Acute Promyelocytic Leukaemia (IC-APL).

Molecular and hematologic relapses in adult patients with acute promyelocytic leukemia: a cohort study

OBJECTIVE

To evaluate factors predictive for relapse in a cohort of adult patients with acute promyelocytic leukemia monitored by molecular methods during consolidation and during at least one month of maintenance therapy.

METHODS

The charts and laboratory data of 65 adult patients with acute promyelocytic leukemia treated according to the International Consortium on Acute Promyelocytic Leukemia 2006 protocol were reviewed. The identification of the promyelocytic leukemia-retinoic acid receptor-alpha gene rearrangement at diagnosis, post-induction, post-consolidation and during maintenance treatment was performed by qualitative and quantitative reverse transcription polymerase chain reaction.

RESULTS

Eighty-nine patients were diagnosed with acute promyelocytic leukemia over a seven-year period and of these 65 were eligible for treatment with the protocol. Among the 45 patients who received consolidation and maintenance treatment, six (13%) relapsed, three of whom presented hematologic and three presented molecular relapse. The first relapses occurred at a median of 39 months. Relapsed patients were from all risk groups (low, intermediate and high) and both morphological types (M3 and M3variant) were found. Three of these patients are alive and in molecular remission after salvage treatment. There were no statistically significant differences regarding gender, age, risk group, morphology, promyelocytic leukemia breakpoint cluster region, use of all-trans retinoic acid, development of differentiation syndrome and number of days to complete remission between the patients who relapsed and those who did not.

CONCLUSION

Our results reinforce the importance of prolonged monitoring of acute promyelocytic leukemia patients using molecular methods to detect relapse early.