Differentiation syndrome in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline chemotherapy: characteristics, outcome, and prognostic factors. Blood. 2009;113:775-783. [PMID: 18945964 DOI: 10.1182/blood-2008-07-168617]

Differentiation syndrome with lower-intensity treatments for acute myeloid leukemia

Differentiation Syndrome (DS) has been identified in a subset of patients undergoing treatment with novel classes of differentiating therapies for acute myeloid leukemia (AML) such as IDH and FLT3 inhibitors. While DS is a well-known treatment-related complication in acute promyelocytic leukemia (APL), efforts are still ongoing to standardize diagnostic and treatment parameters for DS in AML. Though the rates of incidence vary, many of the signs and symptoms of DS are common between APL and AML. So, DS can lead to fatal complications in AML, but prompt management is usually effective and rarely necessitates interruption or discontinuation of AML therapy.

Safety and efficacy of different doses of anthracyclines combined with arsenic trioxide and all-trans retinoic acid in the treatment of de novo acute promyelocytic leukemia

OBJECTIVES

The purpose of this study was to evaluate the efficacy and safety of different doses of anthracyclines combined with arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) for induction in newly diagnosed acute promyelocytic leukemia (APL).

METHODS

One hundred and forty patients were included between January 2011 and December 2017. Seventy patients received low dose anthracycline, ATO and ATRA for induction chemotherapy; and other seventy patients received standard dose anthracycline, ATO and ATRA for induction chemotherapy.

RESULTS

The outcomes of both groups were similar: low dose group versus standard dose group: early mortality 5.7% vs. 10.0% (P = 0.532), disease-free survival (DFS), probabilities of overall-survival (OS) at 2 years 94.6% vs. 95.1% (P = 0.657), 92.8% vs. 88.2% (P = 0.951), respectively. However, the standard-dose group was associated with a longer duration of neutropenia (p < 0.001) and thrombocytopenia (p < 0.001), more volumes of platelets (p = 0.037) and red blood cell transfusions (p < 0.001), and a higher rate of infections (p = 0.042).

CONCLUSION

Low-dose group achieves outcomes similar to those of standard dose group for APL patients, but the low-dose group may be even safer than standard-dose group. So the low-dose anthracycline may be a better choice for newly diagnosed APL patients.

Gilteritinib: potent targeting of FLT3 mutations in AML

Since the discovery of FMS-like tyrosine kinase-3 (FLT3)-activating mutations as genetic drivers in acute myeloid leukemia (AML), investigators have tried to develop tyrosine kinase inhibitors that could effectively target FLT3 and alter the disease trajectory. Giltertinib (formerly known as ASP2215) is a novel compound that entered the field late, but moved through the developmental process with remarkable speed. In many ways, this drug's rapid development was facilitated by the large body of knowledge gained over the years from efforts to develop other FLT3 inhibitors. Single-agent gilteritinib, a potent and selective oral FLT3 inhibitor, improved the survival of patients with relapsed or refractory FLT3-mutated AML compared with standard chemotherapy. This continues to validate the approach of targeting FLT3 itself and establishes a new backbone for testing combination regimens. This review will frame the preclinical and clinical development of gilteritinib in the context of the lessons learned from its predecessors.

Multidisciplinary corroboration in differentiation syndrome: a case report

Background

Differentiation syndrome (DS) is a life-threatening complication that may be seen in patients with acute promyelocytic leukaemia undergoing induction therapy with all-trans retinoic acid or arsenic trioxide. It can lead to severe inflammatory response syndrome and shock if adequate measures are not taken immediately. The radiological features of lung nodules with changes in ground-glass opacity can represent DS. The principal unique feature of the case reported here is that the diagnosis of DS was based on imaging results in the absence of a low total leukocyte count.

Case presentation

A 14-year-old Indian girl diagnosed with acute promyelocytic leukaemia currently undergoing a chemotherapy regimen that included all-trans retinoic acid/arsenic trioxide was sent to the radiology department for investigation of respiratory distress which she had developed soon after the initiation of chemotherapy. Her chest radiograph showed bilateral lower zone lung infiltrates. Computed tomography (CT) revealed changes in ground-glass opacity in the lower lobes with multiple lung nodules. Differential diagnosis included bacterial, viral or fungal infections, leukemic infiltrates, drug toxicity, pulmonary haemorrhage or leukostasis. She was started on dexamethasone immediately after stopping the chemotherapy with all-trans retinoic acid/arsenic trioxide and given ventilatory support. Her condition subsequently improved and her follow-up chest radiograph and CT scan showed a significant reduction of abnormal lung findings. Based on the clinical improvement and the resolution of findings on imaging following the withdrawal of all-trans retinoic acid/arsenic trioxide, we made the diagnosis of DS.

Conclusions

Though a rather unusual possibility, the treatment history of the patient enabled a rather crucial diagnosis in the nick of time and imaging played a pivotal role. This case further iterates the importance of keeping DS in mind when dealing with similar patients in the future.

IDH Inhibitors in AML-Promise and Pitfalls

PURPOSE OF REVIEW

Mutations in isocitrate dehydrogenase genes (IDH1 and IDH2) are common in acute myeloid leukemia (AML), occurring in up to 30% of AML cases. Mutations in IDH leads to abnormal epigenetic regulation in AML cells and blocks differentiation. Inhibitors of mutated IDH1 and IDH2, ivosidenib and enasidenib, respectively, were recently approved by the FDA for relapsed/refractory AML; ivosidenib is also approved for newly diagnosed AML patients not fit for standard chemotherapy. Here, we discuss the clinical development of IDH inhibitors, their unique side effects, and outline future combination approaches in AML.

RECENT FINDINGS

IDH inhibitors are well-tolerated but can induce differentiation of AML cells, which leads to the on-target side effect of differentiation syndrome in up to 20% of patients. Although IDH inhibitors demonstrate efficacy as monotherapy, recent trials have shown that they have higher response rates in combination with hypomethylating agents (HMAs). Current trials of IDH inhibitors include combination with standard induction chemotherapy, as maintenance therapy, and in combination with venetoclax-based regimens. IDH inhibitors are active and have a favorable toxicity profile in AML therapy. Current clinical trials are evaluating how to best incorporate IDH inhibitors into combination therapy to optimize outcomes and duration of response for AML patients with IDH mutations.

Understanding and Managing Sepsis in Patients With Cancer in the Era of Antimicrobial Resistance

Sepsis is a frequent complication in immunosuppressed cancer patients and hematopoietic stem cell transplant recipients that is associated with high morbidity and mortality rates. The worldwide emergence of antimicrobial resistance is of special concern in this population because any delay in starting adequate empirical antibiotic therapy can lead to poor outcomes. In this review, we aim to address: (1) the mechanisms involved in the development of sepsis and septic shock in these patients; (2) the risk factors associated with a worse prognosis; (3) the impact of adequate initial empirical antibiotic therapy given the current era of widespread antimicrobial resistance; and (4) the optimal management of sepsis, including adequate and early source control of infection, optimized antibiotic use based on the pharmacokinetic and pharmacodynamics changes in these patients, and the role of the new available antibiotics.

Potential Effects of the FLT3-ITD Mutation on Chemotherapy Response and Prognosis of Acute Promyelocytic Leukemia

PURPOSE

To evaluate the influence of FLT3-ITD mutations on the treatment response and long-term survival of newly-diagnosed patients with acute promyelocytic leukemia (APL) treated with all-trans retinoic acid and arsenic trioxide.

METHODS

The long-term survival of 90 newly-diagnosed APL patients (age range 12-75 years) was retrospectively analyzed.The FLT3-ITD mutation rate was assayed by polymerase chain reaction (PCR) amplification and sequencing analysis. Its impact on the treatment response, event-free survival(EFS), or overall survival(OS) was investigated in patients with and without the mutations.

RESULTS

The FLT3-ITD mutation rate in newly-diagnosed APL patients was 20% (18/90). The white blood cell (WBC) count at diagnosis in patients with mutations was significantly higher than that in patients without mutations while the FLT3-ITD mutation rate was higher in the high-risk group than in the low/intermediate-risk group. Patients with mutations had a significantly higher early death (ED) rate (16.67% vs 1.39%) for those lacking the mutation (P =0.024). However, the complete remission (CR) and differentiation syndrome (DS) rates in the two groups were similar. Kaplan Meier analysis for EFS and OS at five years showed a significant difference between the patients stratified by FLT3-ITD mutation status (log-rank P =0.010 and P =0.009, respectively).

CONCLUSION

FLT3-ITD mutations can be related to high peripheral WBC counts in APL patients. APL patients with mutations displayed a higher ED rate compared to those without mutations. Patients carrying mutations had reduced five-year EFS and OS rates. Thus, reducing the overall death rate during induction treatment might be an effective way to improve the prognosis of patients with FLT3-ITD mutations.

How I Treat Febrile Neutropenia

The management of febrile neutropenia is a backbone of treating patients with hematologic malignancies and has evolved over the past decades. This article reviews my approach to the evaluation and treatment of febrile neutropenic patients. Key topics discussed include antibacterial and antifungal prophylaxis, the initial workup for fever, the choice of the empiric antibiotic regimen and its modifications, and criteria for discontinuation. For each of these questions, I review the literature and present my perspective.

Acute Promyelocytic Leukemia in Children: A Model of Precision Medicine and Chemotherapy-Free Therapy

Acute promyelocytic leukemia (APL) represents a paradigm of precision medicine. Indeed, in the last decades, the introduction of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) completely revolutionized the therapeutic approach to this previously highly fatal disorder. This entirely chemotherapy-free treatment, which provided excellent survival rates, has been initially validated in adults and, recently, translated in the pediatric setting. This review summarizes currently available data on the use of ATRA and ATO combination in pediatric APL, providing a particular focus on peculiar issues and challenges, such as the occurrence of pseudotumor cerebri and death during induction (early death), as well as the advantage offered by the ATO/ATRA combination in sparing long-term sequelae.

All-Trans Retinoic Acid-Induced Ototoxicity during Chemotherapy in Pediatric Acute Promyelocytic Leukemia

All-trans retinoic acid (ATRA) is known to induce complete remission of acute promyelocytic leukemia (APL) and its use has significantly improved the cure rate of APL. However, ATRA also causes side effects such as differentiation syndrome or intracranial hypertension. In our case, the patient was diagnosed with APL and developed hearing loss thrice while being treated with ATRA. Therefore, we reduced the dose of ATRA instead of stopping it altogether and administered dexamethasone to the patient. A hearing test performed thereafter revealed recovery of hearing. No recurrence of hearing loss occurred after prednisolone and ATRA were combined in the maintenance phase. In conclusion, ATRA-associated hearing loss is reversible, and it is not necessary to stop ATRA. We recommend completion of a randomized clinical trial using dexamethasone in combination with ATRA to prevent hearing loss caused by ATRA.

Differentiation therapy of myeloid leukemia: four decades of development

Acute myeloid leukemia is characterized by arrested differentiation, and agents that overcome this block are therapeutically useful, as shown by the efficacy of all-trans retinoic acid in acute promyelocytic leukemia. However, the early promise of differentiation therapy did not translate into clinical benefit for other subtypes of acute myeloid leukemia, in which cytotoxic chemotherapeutic regimens remained the standard of care. Recent advances, including insights from sequencing of acute myeloid leukemia genomes, have led to the development of targeted therapies, comprising agents that induce differentiation of leukemic cells in preclinical models and clinical trials, thus rejuvenating interest in differentiation therapy. These agents act on various cellular processes including dysregulated metabolic programs, signaling pathways, epigenetic machinery and the cell cycle. In particular, inhibitors of mutant IDH1/2 and FLT3 have shown clinical benefit, leading to approval by regulatory bodies of their use. Besides the focus on recently approved differentiation therapies, this review also provides an overview of differentiation- inducing agents being tested in clinical trials or investigated in preclinical research. Combinatorial strategies are currently being tested for several agents (inhibitors of KDM1A, DOT1L, BET proteins, histone deacetylases), which were not effective in clinical studies as single agents, despite encouraging anti-leukemic activity observed in preclinical models. Overall, recently approved drugs and new investigational agents being developed highlight the merits of differentiation therapy; and ongoing studies promise further advances in the treatment of acute myeloid leukemia in the near future.

Sepsis and Cancer: An Interplay of Friends and Foes

Sepsis and cancer share a number of pathophysiological features, and both result from the inability of the host's immune system to cope with the initial insult (tissue invasion by pathogens and malignant cell transformation, respectively). The common coexistence of both disorders and the profound related alterations in immune homeostasis raise the question of their mutual impact on each other's course. This translational review aims to discuss the interactions between cancer and sepsis supported by clinical data and the translation to experimental models. The dramatic improvement in cancer has come at a cost of increased risks of life-threatening infectious complications. Investigating the long-term outcomes of sepsis survivors has revealed an unexpected susceptibility to cancer long after discharge from the ICU. Nonetheless, it is noteworthy that an acute septic episode may harbor antitumoral properties under particular circumstances. Relevant double-hit animal models have provided clues to whether and how bacterial sepsis may impact malignant tumor growth. In sequential sepsis-then-cancer models, postseptic mice exhibited accelerated tumor growth. When using reverse cancer-then-sepsis models, bacterial sepsis applied to mice with cancer conversely resulted in inhibition or even regression of tumor growth. Experimental models thus highlight dual effects of sepsis on tumor growth, mostly depending on the sequence of insults, and allow deciphering the immune mechanisms and their relation with microorganisms.

Differentiation Syndrome, a Side Effect From the Therapy of Acute Promyelocytic Leukemia

Differentiation Syndrome is a complication of all-trans retinoic acid (ATRA) therapy in patients with acute promyelocytic leukemia (APML). It appears clinically as acute end-organ damage with peripheral edema, hypotension, acute renal failure, and interstitial pulmonary infiltrates. When symptoms develop, physicians are recommended to stop ATRA therapy to minimize complications and reduce mortality immediately. This case report describes a 67-year-old male who was diagnosed with acute promyelocytic leukaemia after he developed episodes of hematuria and easy bruising at home. After beginning a treatment regime of ATRA, steroids, and arsenic, the patient began to have symptoms of differentiation syndrome.

Incidence of Differentiation Syndrome Associated with Treatment Regimens in Acute Myeloid Leukemia: A Systematic Review of the Literature

Differentiation syndrome (DS) is a potentially fatal adverse drug reaction caused by the so-called differentiating agents such as all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), used for remission induction in the treatment of the M3 subtype of acute myeloid leukemia (AML), acute promyelocytic leukemia (APL). However, recent DS reports in trials of isocitrate dehydrogenase (IDH)-inhibitor drugs in patients with IDH-mutated AML have raised concerns. Given the limited knowledge of the incidence of DS with differentiating agents, we conducted a systematic literature review of clinical trials with reports of DS to provide a comprehensive overview of the medications associated with DS. In particular, we focused on the incidence of DS reported among the IDH-inhibitors, compared to existing ATRA and ATO therapies. We identified 44 published articles, encompassing 39 clinical trials, including 6949 patients. Overall, the cumulative incidence of DS across all treatment regimens was 17.7%. Incidence of DS was notably lower in trials with IDH-inhibitors (10.4%) compared to other regimens, including ATRA and/or ATO (15.4-20.6%). Compared to other therapies, the median time to onset was four times longer with IDH-inhibitors (48 vs. 11 days). Treating oncologists should be mindful of this potentially fatal adverse drug reaction, as we expect the current trials represent an underestimation of the actual incidence.

Retrospective Study of Acute Kidney Injury Incidence in Patients with Newly Diagnosed Acute Promyelocytic Leukemia

Purpose

Acute promyelocytic leukemia (APL) constitutes 5–10% of all cases of newly diagnosed acute myeloid leukemia. However, data on the epidemiology and risk factors for acute kidney injury (AKI) in patients with newly diagnosed APL are lacking. This study determined the incidence rate of AKI during induction chemotherapy for patients with newly diagnosed APL and the risk factors for AKI.

Patients and Methods

We conducted a retrospective observational study of patients with newly diagnosed APL in the Shonan Kamakura General Hospital between April 2004 and April 2020. Data of 27 patients with newly diagnosed APL were analyzed. The patients were classified as no AKI and AKI stages 1, 2 or 3.

Results

The incidence rate of AKI during induction chemotherapy was 40% (11/27). Among patients who developed AKI, four patients experienced AKI stage 3, and two patients required renal replacement therapy. No significant differences were found in the white blood cell count and baseline renal function between the groups; however, D-dimer and C-reactive protein levels upon admission were significantly higher in patients with AKI than in patients without AKI. Among patients who developed AKI, in hospital mortality at 90 days was 36% (4/11), which was significantly higher than among patients without AKI (p = 0.02). Patients who developed AKI were administered vancomycin more frequently, while almost all blood culture results were negative.

Conclusion

Incidence of AKI development in patients with newly diagnosed APL during induction chemotherapy was approximately 40%. Moreover, patients who developed AKI tended to be administered vancomycin more frequently. Unnecessary use of vancomycin should be avoided in patients with newly diagnosed APL, and using alternative non-nephrotoxic drugs should be considered for patients at risk of AKI.

Management of fever and neutropenia in the adult patient with acute myeloid leukemia

INTRODUCTION

Febrile neutropenia represents one of the most common treatment-associated complications in the management of acute myeloid leukemia (AML) and is considered an oncologic emergency. Rapid and detailed workup as well as the initiation of empiric broad-spectrum antibiotic therapy are critical to avoid sepsis and to reduce mortality. Although a definitive source of infection is frequently not identified, the severely immunosuppressed status of the AML patient undergoing cytotoxic therapy results in a high risk for a wide array of bacterial, fungal, and viral etiologies.

AREAS COVERED

The authors herein review the diagnostic and therapeutic approach to the neutropenic leukemia patient based on the current knowledge. Special consideration is given to the rapidly changing therapeutic landscape in AML, creating new challenges in the management of infectious complications.

EXPERT OPINION

Multidrug-resistant organisms pose a major challenge in the management of neutropenic fever patients with hematologic malignancies - including AML. Future directions to improve outcomes demand innovative treatment approaches as well as advances in biomarker research to facilitate diagnosis and disease monitoring. Recent achievements in AML-targeted therapy led to an increased incidence of differentiation syndrome, a potentially life-threatening side effect that frequently resembles clinical infection and requires prompt recognition and aggressive intervention.

Soluble RARRES1 induces podocyte apoptosis to promote glomerular disease progression

Using the Nephrotic Syndrome Study Network Consortium data set and other publicly available transcriptomic data sets, we identified retinoic acid receptor responder protein 1 (RARRES1) as a gene whose expression positively correlated with renal function decline in human glomerular disease. The glomerular expression of RARRES1, which is largely restricted to podocytes, increased in focal segmental glomerulosclerosis (FSGS) and diabetic kidney disease (DKD). TNF-α was a potent inducer of RARRES1 expression in cultured podocytes, and transcriptomic analysis showed the enrichment of cell death pathway genes with RARRES1 overexpression. The overexpression of RARRES1 indeed induced podocyte apoptosis in vitro. Notably, this effect was dependent on its cleavage in the extracellular domain, as the mutation of its cleavage site abolished the apoptotic effect. Mechanistically, the soluble RARRES1 was endocytosed and interacted with and inhibited RIO kinase 1 (RIOK1), resulting in p53 activation and podocyte apoptosis. In mice, podocyte-specific overexpression of RARRES1 resulted in marked glomerular injury and albuminuria, while the overexpression of RARRES1 cleavage mutant had no effect. Conversely, podocyte-specific knockdown of Rarres1 in mice ameliorated glomerular injury in the setting of adriamycin-induced nephropathy. Our study demonstrates an important role and the mechanism of RARRES1 in podocyte injury in glomerular disease.

Enasidenib and ivosidenib in AML

The isocitrate dehydrogenases enzymes, IDH1 and IDH2, catalyze the conversion of isocitrate to α-ketoglutarate (αKG) in the cell cytoplasm and mitochondria, respectively, and contribute to generating the dihydronicotinamide-adenine dinucleotide phosphate (NADPH) as reductive potential in different cellular processes. Mutations in IDH1 and IDH2 genes are found collectively in about 20-25% of acute myeloid leukemia (AML) patients. Mutant IDH enzymes have neomorphic activity and convert αKG to the oncometabolite R-2-hydroxyglutarate (R-2-HG) which accumulates at high levels in the cell and hampers the function of αKG-dependent enzymes, including epigenetic regulators, thus leading to altered gene expression and block of differentiation and contributing to leukemia development. Inhibition of the neomorphic mutants induces marked decrease in R-2-HG levels and restores myeloid differentiation. Enasidenib and ivosidenib are potent and selective inhibitors of mutant IDH2 and IDH1, respectively, act as differentiating agents and showed clinical activity in relapsed/refractory (R/R) AML harboring the specific mutation. As single agents, both drugs have been approved by the Food and Drug Administration (FDA) for the treatment of R/R AML. The relevance of IDH targeting within either single agent approach or, most importantly, combinatorial treatments in AML will be discussed.

Predictors of early death, serious hemorrhage, and differentiation syndrome in Japanese patients with acute promyelocytic leukemia

Significant advancements have been achieved with regard to the outcomes of acute promyelocytic leukemia (APL) patients through the introduction of all-trans retinoic acid; however, early hemorrhagic death and differentiation syndrome remain the major causes of remission induction failure in patients with APL. To investigate early death, serious hemorrhage, and differentiation syndrome during remission induction therapy in terms of incidence, risk factors, influence on outcomes, and prophylactic effects of several new anticoagulants, the results of 344 patients enrolled in the Acute Promyelocytic Leukemia 204 study conducted by the Japan Adult Leukemia Study Group were analyzed. Early death was observed in 16 patients (4.7%), of whom 14 had serious hemorrhage and 2 had differentiation syndrome. Serious hemorrhage and differentiation syndrome of grade 2 or higher were observed in 21 and 54 patients, respectively. Patients who achieved complete remission had a 7-year disease-free survival of 84.8% if they did not experience serious hemorrhage and 40.0% if they experienced serious hemorrhage during remission induction therapy (P = 0.001). Risk factor analyses showed that higher white blood cell count was associated with early death, higher white blood cell count and lower platelet count with serious hemorrhage, and leukocytosis during induction therapy and higher body surface area with differentiation syndrome. In conclusion, these results indicate that patients with such high-risk features may benefit from more intensive supportive care. The hemorrhagic risk was not relieved by the introduction of new anticoagulants. Further studies are required to establish the predictive impact of body surface area on differentiation syndrome. This trial is registered with UMIN-CTR as C000000154 on September 13, 2005.

Interleukin-8 is not a predictive biomarker for the development of the acute promyelocytic leukemia differentiation syndrome

Background

Differentiation syndrome (DS) is the main life-threatening adverse event that occurs in acute promyelocytic leukemia (APL) patients treated with all-trans retinoic acid (ATRA). Cytokine imbalances have been reported to play role during the developing of acute promyelocytic leukemia differentiation syndrome (APL-DS). However, the relationship between the plasma cytokine levels and their prognostic value for the prediction of DS developing in patients with APL during the treatment with ATRA and anthracyclines has not been previously reported.

Methods

In this study, we followed an APL cohort (n = 17) over 7 days of ATRA therapy in DS (n = 6) and non-DS groups (n = 11). Interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12p70 and TNF-α were measured in the peripheral blood plasma from 17 patients with APL and 11 healthy adult controls by using the cytometric bead array method.

Results

In non-DS patients, IL-8 plasma levels were significantly reduced in the seventh day of ATRA treatment (34.16; 6.99 to 147.11 pg mL^− 1 in D0 vs. 10.9; 0 to 26.81 pg mL^− 1 in D7; p = 0.02) whereas their levels did not discriminate between DS and non-DS development during the entire induction period (all p > 0.05 in D0, D3, and D7). No significant differences were found in IL-6 levels between groups (p > 0.05 in D0-D7). Other cytokines tested were all undetectable in patients with APL or healthy controls.

Conclusions

We demonstrated that the modulation of IL-8 following ATRA treatment may occur regardless of the development of DS and, therefore, does not appear to be a predictive biomarker to monitor the APL-DS.

Advances and challenges in retinoid delivery systems in regenerative and therapeutic medicine

Retinoids regulate a wide spectrum of cellular functions from the embryo throughout adulthood, including cell differentiation, metabolic regulation, and inflammation. These traits make retinoids very attractive molecules for medical purposes. In light of some of the physicochemical limitations of retinoids, the development of drug delivery systems offers several advantages for clinical translation of retinoid-based therapies, including improved solubilization, prolonged circulation, reduced toxicity, sustained release, and improved efficacy. In this Review, we discuss advances in preclinical and clinical tests regarding retinoid formulations, specifically the ones based in natural retinoids, evaluated in the context of regenerative medicine, brain, cancer, skin, and immune diseases. Advantages and limitations of retinoid formulations, as well as prospects to push the field forward, will be presented.

Differentiating the Differentiation Syndrome Associated with IDH Inhibitors in AML

Isocitrate dehydrogenase (IDH) inhibitors have clinical activity in acute myeloid leukemia, in part, by differentiating blasts to mature myeloid cells. In the largest systematic analysis to date, differentiation syndrome was seen in 19% of patients treated with IDH inhibitors. Early recognition with uniform diagnostic criteria, as utilized in acute promyelocytic leukemia, may reduce subsequent complications.See related article by Norsworthy et al., p. 4280.

RNA-sequencing of acute promyelocytic leukemia primary blasts reveals novel molecular biomarkers of early death events

Although acute promyelocytic leukemia (APL) has evolved to the AML entity with the best prognosis, typical 'early death' (ED) events still account for mortality rates of ∼20% in population-based studies. To investigate this poorly understood issue we performed whole transcriptome analysis of n = 7 APL ED cases compared to n = 7 APL cases with long term remission. We discovered the proteins S100A8/S100A9 and EFEMP1 as the most differentially expressed factors. In an independent cohort of n = 58 APL patients EFEMP1 over-expression was associated with a worse overall survival. Furthermore, a subgroup analysis of ED caused by hemorrhagic complications revealed an association of metallothioneins (MT1G/MT1E) with higher bleeding rates, ED events and negative prognostic effects on overall survival. Finally, we identified a novel TPM4-KLF2 fusion transcripts in 44/64 APL samples. In summary, we report a comprehensive transcriptomic analysis and novel potential biomarkers of ED biology, which highlight novel pathways in ED events in APL.

Case report: An unusual presentation of acute promyelocytic leukemia in a middle aged female mimicking dengue infection

RATIONALE

Acute promyelocytic leukemia (APL) is an uncommon subtype of acute myeloid leukemia (AML). M3v phenotype is a less common presentation of APL and these patients usually present with leukocytosis and abnormal promyelocytes that are characterized by sparse granulation and are less likely to have faggot cells with multiple Auer rods. Distinguishing M3v phenotype from acute febrile illness can be challenging as the diagnosis relies on examination of peripheral smear.

PATIENT CONCERNS

Fifty-seven-year-old female who presented after recent trip to Dominican Republic for high grade fever and gum bleeding. She was exposed to patients with Dengue fever during her stay. At presentation, patient had leukocytosis, thrombocytopenia, and urinalysis showing bacteria and white cell. She was started on treatment for urinary tract infection. Patient remained febrile and thrombocytopenia worsened. On day 2, flow cytometry of the peripheral smear showed 43% medium sized blasts. Fluorescence in situ hybridization was positive for promyelocytic leukemia/retinoic acid receptor alpha.

DIAGNOSES

The patient was diagnosed with APL.

INTERVENTIONS

Patient was started on treatment with all-trans retinoic acid and arsenic trioxide along with supportive care OUTCOMES:: Patient had a favorable clinical response and her symptoms subsided.

LESSONS

Flow cytometry of the peripheral smear is key to diagnosis of suspected APL. One must maintain high suspicion for this life-threatening condition as early diagnosis saves lives.

Acitretin induced lung injury by differentiation syndrome

Differentiation syndrome is a life-threatening complication observed when retinoic acid is given to patients with acute promyelocytic leukemia. Retinoid compounds are also used in non-malignant conditions like psoriasis and it is rare to see differentiation syndrome in such settings. This reports details the clinical presentation and successful management of a patient with psoriasis who developed differentiation syndrome while on treatment with acitretin. The patient was managed with steroids and the differentiation syndrome abated with eventual complete resolution. This report exemplifies the need to consider differentiation syndrome in patients who have non-malignant conditions and are being managed with retoinds.

Extramedullary disease in acute promyelocytic leukaemia: A rare presentation

Acute promyelocytic leukaemia consists of 7%–8% of cases of acute myeloid leukaemia. Extramedullary manifestations are rare and show distinct biological features. We describe a 22-year-old female of Malay ethnicity who presented with fever and a left axillary swelling for a week. The peripheral blood smear showed abnormal promyelocytes with faggot cells. PML-RAR-alpha t(15;17) (q22; q12) was detected by polymerase chain reaction. The left axillary swelling histology and immunohistochemical staining confirmed granulocytic sarcoma. She was induced with triple agents consisting of all-trans-retinoic-acid, arsenic trioxide and idarubicin. On day 14 of induction, she developed severe neutropenic sepsis in which she responded to ventilation and antimicrobials. She completed her induction, consolidation and maintenance therapy. Currently she is in molecular and morphological remission. Extramedullary disease in acute promyelocytic leukaemia usually has a severe clinical presentation. Granulocytic sarcoma may present as an early feature of acute promyelocytic leukaemia.

When Poisons Cure: The Case of Arsenic in Acute Promyelocytic Leukemia

Arsenic has been known for centuries for its double-edged potential: a poison and at the same time a therapeutic agent. The name "arsenikon," meaning "potent," speaks itself for the pharmaceutical properties of this compound, questioned and analyzed for at least 2000 years. In the last decades, acute promyelocytic leukemia (APL) has evolved from a highly fatal to a curable disease, due to the use of all-trans-retinoic acid and, more recently, arsenic trioxide combinations. The success of these entirely chemo-free regimens increased the awareness of APL and reduced the prevalence of early deaths, which was an impending issue in this disease. Further improvements are expected with the next use of oral arsenic formulations, which will allow a complete outpatient approach, at least in the post-induction settings, further improving patients' quality of life. The wide use of standardized approaches in APL will also help unravel long-standing open questions, including the pathogenesis, prevention, and treatment of the differentiation syndrome and of short-term organ toxicities. In the long term, the study of survivorship issues, such as fertility and organ-related and psychological damages, in the increasing number of survivors will help further improve their life after APL.

The prognostic value of CD2, CD4, and HLA-DR expression and FLT3-ITD mutation in adult acute promyelocytic leukemia

In order to explore the prognostic value of CD2, CD4, and human leucocyte antigen-DR (HLA-DR) expression and Fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutation in leukemia cells in the bone marrow of patients with acute promyelocytic leukemia (APL), we retrospectively collected and analyzed the immunophenotype, molecular features and clinical characteristics of 219 newly diagnosed adult patients with APL in Henan Provincial People's Hospital from January 2010 to December 2019. It turned out that the relapse rates of patients with CD2, CD4, or HLA-DR expression and the early mortality rates of patients with CD2 expression, HLA-DR expression, or FLT3-ITD mutation were higher than those of their counterparts. Moreover, reduced overall survival was found for patients who showed CD2 expression, HLA-DR expression or FLT3-ITD mutation. Therefore, CD2 expression, HLA-DR expression and FLT3-ITD mutation were adverse prognostic factors in adults with APL.

Hemorrhage in acute promyelocytic leukemia: Can it be predicted and prevented?

Hemorrhagic death is the leading cause of treatment failure in acute promyelocytic leukemia (APL). Our ability to identify patients at greatest risk of hemorrhage, and to actively prevent hemorrhage, remains limited. Nevertheless, some data is available to guide contemporary clinical practice and future investigation. Circulating disease burden, best represented by the peripheral WBC / blast count, is the most consistent predictor of major and fatal bleeding risk. In contrast, laboratory markers of disseminated intravascular coagulation (DIC) appear to be poor predictors. A number of interventions have been posited to reduce bleeding risk. Prompt initiation of all-trans retinoic acid (ATRA), avoidance of invasive procedures, transfusion support, and cytoreduction all have theoretical merit. Though they lack strong evidence to support their benefit with respect to bleeding, they are associated with limited risks, and are therefore advisable. Low-dose therapeutic heparin and antifibrinolytics have not shown the ability to positively modify bleeding risk, and heparin has been associated with harm. Thrombomodulin has shown promise in limited retrospective studies however further prospective data are needed. rFVIIa may have a role in cases of life-threatening bleeding however evidence is largely anecdotal. Additional studies evaluating the above interventions, and investigating other potential interventions are needed.

Differentiation Syndrome with Ivosidenib and Enasidenib Treatment in Patients with Relapsed or Refractory IDH-Mutated AML: A U.S. Food and Drug Administration Systematic Analysis

PURPOSE

Differentiation syndrome (DS) is a serious adverse reaction of isocitrate dehydrogenase (IDH) inhibitors ivosidenib and enasidenib in patients with (IDH)1- and IDH2-mutated acute myeloid leukemia (AML), respectively.

EXPERIMENTAL DESIGN

During FDA review of marketing applications for ivosidenib and enasidenib, data from pivotal trials were queried to identify cases of DS in patients with relapsed or refractory (R/R) AML. One hundred seventy-nine patients with R/R AML received ivosidenib and 214 received enasidenib. Adverse events, labs, and vital signs in the first 90 days of treatment were screened per diagnostic criteria, and narratives were reviewed to adjudicate DS cases.

RESULTS

We identified 72 of 179 (40%) potential cases for ivosidenib and 86 of 214 (40%) for enasidenib; 34 of 179 (19%) and 41 of 214 (19%) were adjudicated as DS. Leukocytosis was present in 79% and 61% of cases, respectively. Median (range) time to onset was 20 (1-78) and 19 (1-86) days. Grade ≥ 3 adverse reactions occurred in 68% and 66%; 6% and 5% were fatal. Univariate analyses suggested baseline bone marrow blasts ≥ 48% and peripheral blood blasts ≥ 25% and 15% for ivosidenib and enasidenib, respectively, were associated with increased risk of DS. Complete remission (CR) + CR with partial hematologic recovery rates were lower in patients with versus without DS [ivosidenib 18% (95% confidence interval, 7%-35%) vs. 36% (28%-45%); enasidenib 18% (7%-33%) vs. 25% (18%-32%)].

CONCLUSIONS

DS is a common and potentially fatal adverse reaction of IDH inhibitors, and use of standardized diagnostic criteria may aid in earlier diagnosis and treatment.See related commentary by Zeidner, p. 4174.

Treatment outcomes of patients with acute promyelocytic leukaemia between 2000 and 2017, a retrospective, single centre experience

All-trans retinoic acid (ATRA) and arsenic trioxide (ATO) are effective induction therapy for acute promyelocytic leukaemia (APL). However, early thrombo-haemorrhagic complications and mortality remain high. We aimed to investigate how the timing of ATRA initiation and the inclusion of ATO influence patient outcomes. Clinical records were retrospectively reviewed for all patients treated for APL in a single, tertiary centre during 2000-2017. Among 70 patients with APL, 36 (51.4%) presented with thrombo-haemorrhagic complications, and four (5.8%) died within 30 days. The median time to ATRA initiation was 11.2 (range 0-104) h from the time of admission. Patients requiring more transfusions started on ATRA sooner (P = 0.04). Patients with adverse early events did not start ATRA later (P = 0.99). Nevertheless, patients that required additional tests for diagnosis (PML immunofluorescence or molecular) started on ATRA later (28.5 versus 5.3 h; P < 0.0001), and had more thrombo-haemorrhagic complications (P = 0.04). Long-term survival was actually better in patients who started ATRA later (P = 0.03), which is likely explained by higher proportion of low risk patients in this group. Patients treated with ATO (n = 23) maintained higher fibrinogen levels and required less transfusions during induction (P < 0.05), with no disease-related deaths in this group over a median follow-up time of 37.8 months (interquartile range 44.9 months). In summary, fast ATRA initiation reduces early but not late adverse events in APL patients, and the inclusion of ATO helps further improve both early and late outcomes in APL.

Treatment of acute promyelocytic leukemia in older patients: recommendations of an International Society of Geriatric Oncology (SIOG) task force

Approximately one third of patients diagnosed with acute promyelocytic leukemia (APL) are above the age of sixty. It is important to ensure older adults receive optimal diagnosis and management since this subtype of acute myeloid leukemia - given appropriate treatment - is highly curable with lower risk of adverse events compared to other types of leukemia. Historically, older age has been a risk factor for early death and poorer overall survival. However, prospects have changed with the introduction of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). APL is curable in the majority of patients regardless of age, and the threshold of fitness that makes ATRA/ATO therapy possible is likely to be lower than for cytotoxic chemotherapy. APL frequently presents as a medical emergency and rapid diagnosis and intervention - typically involving referral to a specialist centre - is a major determinant of outcome. After diagnosis, management of APL in older adults presents particular challenges. Geriatric assessment, including evaluation of frailty, comorbidities and polypharmacy can assist in providing optimal supportive care for older adults during remission induction and may help individualize therapy in the post-remission phase. Here, we review the available evidence, highlighting areas of consensus, gaps in evidence and opportunities for research to enhance diagnosis, management and survivorship for older patients.

Epigenetic activation of O-linked β-N-acetylglucosamine transferase overrides the differentiation blockage in acute leukemia

Background

Overriding the differentiation blockage in acute myeloid leukemia (AML) is the most successful mode-of-action in leukemia therapy – now curing the vast majority of patients with acute promyelocytic leukemia (APL) using all-trans retinoic acid (ATRA)-based regimens. Similar approaches in other leukemia subtypes, such as IDH1/2-mutated AML, are under active investigation. We herein present successful release of the differentiation blockage upon treatment with the natural (−)-Δ⁹-Tetrahydrocannabinol isomer dronabinol in vitro and in vivo.

Methods

Cellular maturation and differentiation were followed in two patients employing whole genome methylation profiling, proteome analyses, NGS deep sequencing and multispectral imaging flow cytometry. For functional studies lentiviral OGT knock-down in vitro and ex vivo cell models were created to evaluate proliferative, apoptotic and differentiating effects of OGT in acute leukemia.

Findings

In here, we provide molecular evidence that dronbinol is capable to override the differentiation blockage of acute leukemia blasts at the state of the leukemia-initiating clone. We further identify the O-linked β-N-acetyl glucosamine (O-GlcNAc) transferase (OGT) to be crucial in this process. OGT is a master regulator enzyme adding O-GlcNAc to serine or threonine residues in a multitude of target proteins. Aberrant O-GlcNAc modification is implicated in pathologies of metabolic, neurodegenerative and autoimme diseases as well as cancers. We provide evidence that dronabinol induces transcription of OGT via epigenetic hypomethylation of the transcription start site (TSS). A lentiviral OGT-knock out approach proves the central role of OGT exerting antileukemic efficacy via a dual-mechanism of action: High concentrations of dronabinol result in induction of apoptosis, whereas lower concentrations drive cellular maturation. Most intriguingly, overriding of the differentiation blockage of acute leukemia blasts is validated in vivo following two patients treated with dronabinol.

Interpretation

In conclusion, we provide evidence for overcoming the differentiation blockage in acute leukemia in subentities beyond promyelocytic and IDH1/2-mutated leukemia and thereby identify O-GlcNAcylation as a novel (drugable) field for future leukemia research.

Funding

Unrestricted grant support by the IZKF Program of the Medical Faculty Tübingen (MMS) and Brigitte Schlieben-Lange Program as well as the Margarete von Wrangell Program of the Ministry of Science, Research and the Arts, Baden-Württemberg, Germany (KKS) and Athene Program of the excellence initiative University of Tübingen (KKS).

Benefits of Combined All-Trans Retinoic Acid and Arsenic Trioxide Treatment of Acute Promyelocytic Leukemia Cells and Further Enhancement by Inhibition of Atypically Expressed Transglutaminase 2

Randomized trials in acute promyelocytic leukemia patients have shown that treatment with a combination of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) is superior in efficacy to monotherapy, with significantly decreased mortality. So far, there are little data available to explain the success of the ATRA and ATO combination treatment in molecular terms. We showed that ATRA- and ATO-treated cells had the same capacity for superoxide production, which was reduced by two-thirds in the combined treatment. Secreted inflammatory biomarkers (monocyte chemoattractant protein-1 [MCP-1], interleukin-1 beta [IL-1β] and tumor necrosis factor-α [TNF-α]) were significantly decreased and were further reduced in a transglutaminase 2 (TG2) expression-dependent manner. The amount of secreted TNF-α in the supernatant of NB4 TG2 knockout cells was close to 50 times lower than in ATRA-treated differentiated wild-type NB4 cells. The irreversible inhibitor of TG2 NC9 not only decreased reactive oxygen species production 28-fold, but decreased the concentration of MCP-1, IL-1β and TNF-α 8-, 15- and 61-fold, respectively in the combined ATRA + ATO-treated wild-type NB4 cell culture. We propose that atypical expression of TG2 leads to the generation of inflammation, which thereby serves as a potential target for the prevention of differentiation syndrome.

Enasidenib in patients with mutant IDH2 myelodysplastic syndromes: a phase 1 subgroup analysis of the multicentre, AG221-C-001 trial

BACKGROUND

Mutations in isocitrate dehydrogenase-2 (IDH2) occur in around 5% of patients with myelodysplastic syndromes. Neomorphic activity of mutant IDH2 proteins results in hypermethylation of DNA and histones, leading to blocked haemopoietic differentiation. Enasidenib, an inhibitor of mutated IDH2 proteins, induces responses in patients with IDH2-mutated, relapsed or refractory acute myeloid leukaemia. We aimed to establish the clinical outcomes of enasidenib monotherapy in a subgroup of patients with myelodysplastic syndromes harbouring mutations in IDH2 from the AG221-C-001 trial.

METHODS

The multicentre, open-label, phase 1-2 AG221-C-001 trial enrolled patients with advanced haematological malignancies (2008 WHO criteria) harbouring an IDH2 mutation. The present study is a subgroup analysis of patients with IDH2-mutated myelodysplastic syndromes in the phase 1 dose-escalation and expansion portions of the trial. Patients with myelodysplastic syndromes were aged 18 years or older with an ECOG performance status score of 2 or lower, and were relapsed or refractory to, or ineligible for, standard treatments. Patients received oral doses of enasidenib at 60-300 mg per day in repeated 28-day treatment cycles. In this subgroup analysis, we focused on the safety and activity of enasidenib as main outcomes. Overall response rate, duration of response, and overall and event-free survival analyses were by intention-to-treat. Safety was assessed in all participants who received at least one dose of study drug in terms of treatment-emergent adverse events. The AG221-C-001 trial is registered on ClinicalTrials.gov, NCT01915498, status ongoing but closed to recruitment.

FINDINGS

17 patients with myelodysplastic syndromes harbouring an IDH2 mutation (median age, 67·0 years [IQR 60·5-73·0]) were enrolled between Feb 18, 2014, and Sept 1, 2015. At data cutoff (Oct 1, 2018), after a median follow-up of 11·0 months (IQR 6·8-23·0), all patients had discontinued enasidenib, with a median of 3 treatment cycles (2-15) for all patients (five [29%] received ≥12 cycles). At entry, three (18%) patients had relapsed after allogeneic stem-cell transplants, 13 (76%) had previously received therapy with hypomethylating agents, and ten (59%) had received at least two previous therapies. No dose-limiting toxicities were reported. The most common treatment-emergent adverse events were diarrhoea and nausea (in nine [53%] patients each). Most common grade 3-4 treatment-emergent adverse events were indirect hyperbilirubinaemia (in six [35%] patients), pneumonia (in five [29%] patients), and thrombocytopaenia (in four [24%] patients). Serious treatment-emergent adverse events in more than one patient were pneumonia (in five [29% patients); tumor lysis syndrome (in three [18%] patients); and sepsis, atrial flutter, indirect hyperbilirubinaemia, cerebral hemorrhage, and mental status change (in two [12%] patients each). No treatment-related deaths occurred. An overall response was achieved in 9 patients (53% [95% CI 28-77]), with a median duration of response of 9·2 months (95% CI 1·0-not reached). Six (46%) of 13 patients previously treated with hypomethylating agents responded. Median overall survival was 16·9 months (95% CI 1·5-32·3), and median event-free survival was 11·0 months (1·5-16·7).

INTERPRETATION

Enasidenib is generally well tolerated and can induce responses in patients with mutant IDH2 myelodysplastic syndromes, including in those who have had previous therapy with hypomethylating agents. Testing for IDH2 mutations in myelodysplastic syndromes is essential for identifying patients who might benefit from enasidenib therapy, including those patients in whom conventional treatments have been unsuccessful.

FUNDING

Celgene and Agios Pharmaceuticals.

From Bench to Bedside and Beyond: Therapeutic Scenario in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a heterogeneous group of clonal disorders characterized by abnormal proliferation of undifferentiated myeloid progenitors, impaired hematopoiesis, and variable response to therapy. To date, only about 30% of adult patients with AML become long-term survivors and relapse and/or disease refractoriness are the major cause of treatment failure. Thus, this is an urgent unmet clinical need and new drugs are envisaged in order to ameliorate disease survival outcomes. Here, we review the latest therapeutic approaches (investigational and approved agents) for AML treatment. A specific focus will be given to molecularly targeted therapies for AML as a representation of possible agents for precision medicine. We will discuss experimental and preclinical data for FLT3, IDH1, BCL-2, Hedgehog pathway inhibitors, and epitherapy.

Complications and Toxicities Associated with Cancer Therapies in the Intensive Care Unit

Advances in the management of hematologic malignancies and solid tumors have given rise to diverse modalities to treat cancer other than cytotoxic chemotherapy, including targeted therapies, immunotherapies, and cellular therapies. Currently, there are over 175 FDA-approved antineoplastic agents in the United States, many with a diverse and profound toxicity profile. Complications of antineoplastic therapy may result in the need for intensive care unit (ICU) admission to provide acute symptom management. Accordingly, ICU providers caring for cancer patients should have a working knowledge of the toxicities and complications associated with antineoplastic therapy.

Outcomes in Adult Acute Promyelocytic Leukemia: A Decade Experience

BACKGROUND

Acute promyelocytic leukemia (APL), a distinct variant of acute myeloid leukemia (AML), accounts for 10% of AML cases. Over the past decade, APL has emerged from a highly fatal disease to a highly curable one. The published data on outcomes of APL from India are scant. The present study was designed to analyze the clinicopathologic features and outcomes in adult APL.

MATERIALS AND METHODS

The present report is a single institutional, observational, retrospective study, and data of patients diagnosed with APL from 2006 to 2018 were analyzed. All patients with APL, diagnosed by morphology and confirmed by reverse transcriptase polymerase chain reaction (promyelocytic leukemia/retinoic acid receptor alpha) and over 18 years of age, were included in this study. SPSS software v25.1 was used for statistical analysis.

RESULTS

A total of 1396 patients with AML were seen between January 2005 and June 2018, of which 190 (13.6%) had APL. Of these, 111 patients met the inclusion criteria and were analyzed. The median age at presentation was 33 years (range, 19-60 years). The median duration of symptoms before presentation was 15 days (range, 3-180 days). High risk, intermediate risk, and low risk were seen in 43.3%, 41.4%, and 15.3% of patients, respectively. At the end of induction chemotherapy, 88 (79%) patients achieved complete hematologic remission, and 23 (21%) succumbed during induction. The median time to attain complete hematologic remission was 30 days (range, 19-47 days). At a median follow-up of 34 months, the event-free survival and overall survival were 69.3% and 74.7%, respectively. On univariate analysis, bcr3 variant and high-risk category at presentation had significant impact on event-free survival (P = .029 and P = .003, respectively) and overall survival (P ≤ .001 and P = .007, respectively). On multivariate analysis, only high risk at presentation was significant for event-free survival (P = .04) and overall survival (P = .02).

CONCLUSION

APL constituted one-tenth of patients with AML. The majority of patients were high risk at presentation. Sanz high risk category and bcr3 variant at presentation had significant impact on outcomes in APL.

Acute promyelocytic leukemia (APL): remaining challenges towards a cure for all

The application of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) has revolutionized the treatment of acute promyelocytic leukemia (APL). More than 80-90% of patients are expected to be cured with a combination of ATRA, ATO and/or chemotherapy. In this review, we focus on the remaining obstacles to a cure for all patients with APL. We review the issue of early death and coagulopathy and discuss the particular challenges in the care of patients with high-risk APL and patients with relapsed APL. We also give recommendations and highlight ongoing efforts to improve the persistently high early death rate and the outcomes of high risk and relapsed APL patients.

Rate of differentiation syndrome in patients based on timing of initial all-trans retinoic acid administration

All-trans-retinoic acid (ATRA) is the standard of care for the management of acute promyelocytic leukemia (APL), but can be associated with differentiation syndrome (DS). Over a seven-year period, we sought to determine the impact of ATRA initiation time on the development of DS. ATRA administration time had no impact on DS occurrence (p = =0.13), APL risk (p = =0.28) or regimen received (p = =0.1). Patients with higher mean body mass index (BMI) were more likely to develop moderate or severe DS (p = =0.02). Early treatment of APL is essential and maybe strongly considered in patients with elevated BMI.

Characteristics and outcome of adult patients with acute promyelocytic leukemia and increased body mass index treated with the PETHEMA Protocols

OBJECTIVE

The obesity/overweight may have an influence on APL outcomes.

METHODS

This is the biggest multicentre analysis on 1320 APL patients treated with AIDA-induction and risk-adapted consolidation between 1996 and 2012. Patients body mass index (BMI) was classified as underweight (<18.5 kg/m² ), normal (18.5-25 kg/m² ), overweight (25-29.9 kg/m² ), and obese (≥30 kg/m² ) according to the World Health Organization (WHO) criteria.

RESULTS AND CONCLUSIONS

Relationship between male gender, older age, and other known laboratory abnormalities in overweight/obese patients was significant. The induction mortality rate was significantly higher in APL with BMI ≥25 vs BMI <25 (10% vs 6%; P = .04). APL patients with BMI ≥25 had a trend to lower OS (74% vs 80%; P = .06). However, in the multivariate analysis, BMI did not retain the independent predictive value (P = .46). There was no higher incidence of differentiation syndrome with BMI ≥25, but there was a trend in obese. There was no difference in relapse rate according to the BMI. In summary, overweight/obesity does not represent an independent risk factor for APL outcomes. The influence of obesity in APL patients treated with chemotherapy-free regimens remains to be established.

Long-term follow-up of children with acute promyelocytic leukemia treated with Beijing Children's Hospital APL 2005 protocol (BCH-APL 2005)

We studied the outcomes of children with APL treated by the Beijing Children's Hospital's (BCH) acute promyelocytic leukemia (APL) 2005 protocol (BCH-APL2005). The clinical data of 77 patients enrolled from January 2005 to June 2015 were analyzed retrospectively. The hematologic complete remission (CR) rate and overall survival (OS) rate were evaluated between standard-risk (SR) and high-risk (HR) groups. Prognostic factors and complications were investigated in these two groups. CR in the SR and HR groups was 96.4% (54/56) and 85.7% (18/21), respectively, while the 10-year OS was 94.6% (53/56) and 76.2% (16/21), respectively. The cumulative incidence of early death was 6.5% (5/77), and the SR and HR groups were 1.8% (1/56) and 19.0% (4/21), respectively. Only two patients relapsed, and the relapse rate was 2.6% (2/77). According to Kaplan-Meier analysis, the SR group had a significantly better long-term survival than HR counterparts (p= .016). Initial leukocyte count was the only prognostic factor (p= .016) by univariate analysis, while other factors, such as FLT3-ITD and platelet count, had no correlation with prognosis. In addition, early deaths were mainly due to intracranial hemorrhage. Although the combination of all-trans retinoic acid (ATRA) and chemotherapy can improve the outcome of APL patients, the early deaths and anthracycline-related cardiac toxicity were relatively higher in our study. Current efforts focus on reducing or even avoiding chemotherapy in APL children and rest on the frontline regimen of intravenous arsenic trioxide or oral realgar-indigo naturalis formula plus ATRA, which is the direction for APL treatment.