How I treat acute promyelocytic leukemia

Exploiting Omic-based Approaches to Decipher Traditional Chinese Medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese Medicine (TCM), an ancient health system, faces significant research challenges due to the complexity of its active components and targets, as well as a historical lack of detailed annotation. However, recent advances in omics technologies have begun to unravel these complexities, providing a more informed and nuanced understanding of TCM's therapeutic potential in contemporary healthcare.

AIM OF THE REVIEW

This review summarizes the application of omics technologies in TCM modernization, emphasizing components analysis, quality control, biomarker discovery, target identification, and treatment optimization. In addition, future perspectives on using omics for precision TCM treatment are also discussed.

MATERIALS AND METHODS

We have explored several databases (including PubMed, ClinicalTrials, Google Scholar, and Web of Science) to review related articles, focusing on Traditional Chinese Medicine, Omics Strategy, Precision Medicine, Biomarkers, Quality Control, and Molecular Mechanisms. Paper selection criteria involved English grammar, publication date, high citations, and broad applicability, exclusion criteria included low credibility, non-English publications, and those full-text inaccessible ones.

RESULTS

TCM and the popularity of Chinese herbal medicines (CHMs) are gaining increasing attention worldwide. This is driven, in part, by a large number of technologies, especially omics strategy, which are aiding the modernization of TCM. They contribute to the quality control of CHMs, the identification of cellular targets, discovery of new drugs and, most importantly, the understanding of their mechanisms of action.

CONCLUSION

To fully integrate TCM into modern medicine, further development of robust omics strategies is essential. This vision includes personalized medicine, backed by advanced computational power and secure data infrastructure, to facilitate global acceptance and seamless integration of TCM practices.

Chemotherapy-free approaches to newly-diagnosed acute promyelocytic leukaemia: is oral-arsenic trioxide/all-trans retinoic acid/ascorbic acid the answer?

INTRODUCTION

Acute promyelocytic leukemia (APL) is a distinct form of acute myeloid leukemia characterized by the presence of t(15;17)(q24;21) and the PML:RARA gene fusion. Frontline use of intravenous arsenic trioxide (i.v.-ATO) and all-trans retinoic acid (ATRA) has vastly improved cure rates in APL. Researchers in Hong Kong invented the oral formulation of ATO (oral-ATO) and have confirmed a bioavailability comparable to i.v.-ATO. A plethora of studies have confirmed the safety and efficacy of oral-ATO-based regimens in the frontline and relapsed setting.

AREAS COVERED

Aspects on the development of oral-ATO-based regimens for APL in the frontline and relapsed setting are discussed. The short-term and long-term safety and efficacy of oral-ATO-based regimens are discussed. The frontline use of oral-ATO in combination with ATRA and ascorbic acid (AAA) induction in a 'chemotherapy-free' is highlighted.

EXPERT OPINION

Current and ongoing data on the use of oral-ATO-based regimens in APL support the use of oral-ATO as an alternative to i.v.-ATO allowing a more convenient and economical approach to the management of APL.

Hemorrhage in acute promyelocytic leukemia-fibrinolysis in focus

Coagulopathy continues to be a major challenge in the management of patients with acute promyelocytic leukemia (APL). Novel differentiating agents have led to improved survival in these patients, but perturbations in coagulation continue to have an impact on their prognosis. The most worrisome of coagulation disturbances is bleeding, which is not an uncommon cause of early death in APL. Despite this, there are no consistent predictors of this high risk of fatal hemorrhage in APL. In this context, the fibrinolytic system has been identified as a crucial role player in APL coagulopathy. However, the current guidelines for the management of APL give little regard to tests that measure the fibrinolytic system while giving more importance to close monitoring of conventional coagulation tests and platelet counts to identify the coagulopathy. More recently, viscoelastic tests have come to usefulness in determining global hemostasis and have been widely used for "diagnosing" hyperfibrinolysis in selected clinical settings. In this review, we attempt to describe risk assessment models for diagnosing APL coagulopathy, describe the possible application of viscoelastic tests in this setting, and persuade clinicians to reconsider the use of antifibrinolytics to improve survival of APL patients.

Differentiation syndrome associated with treatment with IDH2 inhibitor enasidenib: pooled analysis from clinical trials

ABSTRACT

Treatment with enasidenib, a selective mutant isocitrate dehydrogenase isoform 2 (IDH2) inhibitor, has been associated with the development of differentiation syndrome (DS) in patients with acute myeloid leukemia (AML). Studies on the incidence and clinical features of DS are limited in this setting, and diagnosis is challenging because of nonspecific symptoms. This study assessed the incidence, diagnostic criteria, risk factors, and correlation with clinical response of DS based on the pooled analysis of 4 clinical trials in patients with IDH2-mutated AML treated with enasidenib as monotherapy, or in combination with azacitidine or with chemotherapy. Across the total AML population, 67 of 643 (10.4%) had ≥1 any-grade DS event, with highest incidence in patients who received enasidenib plus azacitidine and lowest incidence in patients who received enasidenib plus chemotherapy (13/74 [17.6%] and 2/93 [2.2%]). The most common symptoms of DS were dyspnea/hypoxia (80.6%) and pulmonary infiltrate (73.1%). Median time to onset of first DS event across all studies was 32 days (range, 4-129). Most patients (88.1%) received systemic steroids for treatment of DS. Evaluation of baseline risk factors for DS identified higher levels of bone marrow blasts and lactate dehydrogenase as independent factors associated with increased grade 3 to 5 DS risk. Overall, these results suggest that DS associated with IDH inhibition is manageable, given the benefits of enasidenib treatment in IDH2-mutated AML. We further characterized enasidenib-related DS in these patients and identified risk factors, which could be used for DS management in clinical practice. These trials were registered at www.ClinicalTrials.gov as # NCT01915498, NCT02577406, NCT02677922, and NCT02632708.

Treatment of a Patient with Acute Promyelocytic Leukemia with Multiple Isolated Relapses in the Central Nervous System: A Case Report and Mini-Review of the Literature

The efficacy of therapeutics for acute promyelocytic leukemia (APL) has exhibited an increase in recent years. Only a few patients experience relapse, including extramedullary relapse, and in patients with extramedullary relapse, the central nervous system (CNS) is the most common site. To date, there is no expert consensus or clinical guidelines available for CNS relapse, at least to the best of our knowledge. The optimal therapeutic strategy and management options for these patients remain unclear. The present study reports the treatment of a patient with APL with multiple isolated relapses in the CNS. In addition, through a mini-review of the literature, the present study provides a summary of various reports of this disease and discusses possible treatment options for these patients.

The influence of hospital volume and physician volume on early mortality in acute promyelocytic leukemia patients

Acute promyelocytic leukemia (APL) is a highly curable hematologic malignancy in the era of all-trans retinoic acid (ATRA) combination treatment. However, only a modest change in early mortality rate has been observed despite the wide availability of ATRA. In addition to the clinical characteristics of APL patients, studies on the hospital volume-outcome relationship and the physician volume-outcome relationship remained limited. We aim to evaluate the association between hospital and physician volume and the early mortality rate among APL patients. The patients were collected from Taiwan's National Health Insurance Research Database (NHIRD). Early mortality is defined as death within 30 days of diagnosis. Patients were categorized into four groups according to individual cumulative hospital and physician volume. The risk of all-cause mortality in APL patients with different cumulative volume groups was compared using a Cox proportional hazard model. The probability of overall survival was estimated using the Kaplan-Meier method. All 741 patients were divided into four quartile volume groups. In the multivariate analysis, only physician volume was significantly associated with early mortality rate. The physician volume of the highest quartile was a protective factor for early mortality compared with the physician volume of the lowest quartile (HR 0.10, 95% CI 0.02-0.65). Hospital characteristics were not associated with early mortality. In the sensitivity analyses, the results remained consistent using two other different definitions of early mortality. Higher physician volume was independently associated with lower early mortality, while hospital volume was not. Enhancing the clinical expertise of low-volume physicians may ensure better outcomes.

Central venous catheters do not increase the hemorrhagic risk in acute promyelocytic leukemia patients during induction therapy

In acute promyelocytic leukemia (APL), hemorrhage, particularly intracranial hemorrhage, is the most common cause of early death. A central venous catheter (CVC) may provide a greater guarantee of safety and comfort to APL patients. However, CVCs have seldom been attempted in APL patients during induction therapy because of concerns about increasing the risk of hemorrhagic complications after this invasive procedure. To evaluate the hemorrhagic risk after CVC placement in APL patients during induction therapy, we retrospectively analyzed 95 newly diagnosed patients with APL from January 2010 to December 2022. Among these patients, 39 patients in the CVC group and 56 patients in the non-CVC group were included. Laboratory and clinical parameters of the two groups were collected and compared. There were no significant differences in median platelet, fibrinogen (Fbg), D-dimer, prothrombin time (PT), white blood count (WBC) and hemoglobin (Hb) between the CVC and non-CVC groups on the first day of the visit (day 0) and the following days (day 4, day 7, day 11, day 14, day 18 and day 21) (p = 0.382, p = 0.805, p = 0.456, p = 0.902, p = 0.901 and p = 0.097, respectively). The consumption of transfused platelets and Fbg was not significantly different between the CVC group and non-CVC group (5.0 vs. 4.5 units, p = 0.34, and 6.8 vs. 6.0, p = 0.36, respectively). The last day of platelet and Fbg transfusion was also not significantly different (21 vs. 19, p = 0.238 and 7.5 vs. 8.5, p = 0.684, respectively). The incidences of total hemorrhagic events and hemorrhagic death were lower in the CVC group than in the non-CVC group (17.9% vs. 37.5%, p = 0.04 and 0% vs. 16.1%, p = 0.01, respectively). The 30-day survival rate was not significantly different (92.3% vs. 82.1%, respectively, p = 0.145) for the CVC group compared with the non-CVC group. Our study suggested that CVCs did not increase the hemorrhagic risk in APL patients during induction therapy and that a CVC should be considered in this type of clinical situation.

Hypercalcemia associated with interaction between all trans retinoic acid and fluconazole in an acute promyelocytic leukemia and acquired hypoparathyroidism case

INTRODUCTION

Acute promyelocytic leukemia (APL) is the most malignant form of acute myeloid leukemia (AML) with short survival without treatment. All trans retinoic acid (ATRA) is a vitamin A metabolite and plays an important role in the treatment of APL. Hypercalcemia is a rare side effect of ATRA.

CASE REPORT

A 67-year-old female patient was investigated due to widespread bruising and pancytopenia. The patient was diagnosed with APL and remission was achieved by administering idarubicin together with ATRA in the induction treatment. The patient has hypocalcemia due to acquired hypoparathyroidism, and it was observed that the calcium level increased with the initiation of fluconazole 200 mg/day for antifungal prophylaxis together with ATRA in the consolidation treatment. It was observed that the calcium value reached 13 mg/dL by increasing the fluconazole to 400 mg/day treatment dose due to oral mucositis.

MANAGEMENT AND OUTCOME

The development of hypercalcemia has been reported in previous case reports when ATRA is used together with voriconazole, fosfluconazole, itraconazole, and posaconazole, which inhibit cytochrome P450 enzymes. In this case, it is the first in the literature that a patient with hypocalcemia due to acquired hypoparathyroidism developed hypercalcemia after fluconazole and ATRA were used together.

DISCUSSION

Since hypercalcemia may develop while azole drugs are administered during ATRA treatment, it is important to monitor calcium levels to prevent complications of hypercalcemia.

Differentiation syndrome and coagulation disorder - comparison between treatment with oral and intravenous arsenics in pediatric acute promyelocytic leukemia

Realgar-Indigo naturalis formula (RIF), with A₄S₄ as a major ingredient, is an oral arsenic used in China to treat pediatric acute promyelocytic leukemia (APL). The efficacy of RIF is similar to that of arsenic trioxide (ATO). However, the effects of these two arsenicals on differentiation syndrome (DS) and coagulation disorders, the two main life-threatening events in children with APL, remain unclear. We retrospectively analyzed 68 consecutive children with APL from South China Children Leukemia Group-APL (SCCLG-APL) study. Patients received all-trans retinoic acid (ATRA) on day 1 of induction therapy. ATO 0.16 mg/kg day or RIF 135 mg/kg·day was administrated on day 5, while mitoxantrone was administered on day 3 (non-high-risk) or days 2-4 (high-risk). The incidences of DS were 3.0% and 5.7% in ATO (n = 33) and RIF (n = 35) arms (p = 0.590), and 10.3% and 0% in patients with and without differentiation-related hyperleukocytosis (p = 0.04), respectively. Moreover, in patients with differentiation-related hyperleukocytosis, the incidence of DS was not significantly different between ATO and RIF arms. The dynamic changes of leukocyte count between arms were not statistically different. However, patients with leukocyte count > 2.61 × 10⁹/L or percentage of promyelocytes in peripheral blood > 26.5% tended to develop hyperleukocytosis. The improvement of coagulation indexes in ATO and RIF arms was similar, with fibrinogen and prothrombin time having the quickest recovery rate. This study showed that the incidence of DS and recovery of coagulopathy are similar when treating pediatric APL with RIF or ATO.

Detection of acute promyelocytic leukemia in peripheral blood and bone marrow with annotation-free deep learning

While optical microscopy inspection of blood films and bone marrow aspirates by a hematologist is a crucial step in establishing diagnosis of acute leukemia, especially in low-resource settings where other diagnostic modalities are not available, the task remains time-consuming and prone to human inconsistencies. This has an impact especially in cases of Acute Promyelocytic Leukemia (APL) that require urgent treatment. Integration of automated computational hematopathology into clinical workflows can improve the throughput of these services and reduce cognitive human error. However, a major bottleneck in deploying such systems is a lack of sufficient cell morphological object-labels annotations to train deep learning models. We overcome this by leveraging patient diagnostic labels to train weakly-supervised models that detect different types of acute leukemia. We introduce a deep learning approach, Multiple Instance Learning for Leukocyte Identification (MILLIE), able to perform automated reliable analysis of blood films with minimal supervision. Without being trained to classify individual cells, MILLIE differentiates between acute lymphoblastic and myeloblastic leukemia in blood films. More importantly, MILLIE detects APL in blood films (AUC 0.94 ± 0.04) and in bone marrow aspirates (AUC 0.99 ± 0.01). MILLIE is a viable solution to augment the throughput of clinical pathways that require assessment of blood film microscopy.

Acute promyelocytic leukaemia: population-based study of epidemiology and outcome with ATRA and oral-ATO from 1991 to 2021

BACKGROUND

The epidemiology and treatment of acute promyelocytic leukaemia (APL) are changing. We have incorporated oral arsenic trioxide (oral-ATO) into induction/maintenance.

METHODS

Newly-diagnosed APL from 1991 to 2021 divided into three 10-year periods were studied to define its epidemiology and how oral-ATO impacted on its outcome. Primary endpoints included APL incidence, early deaths (ED, first 30 days), and overall survival (OS). Secondary endpoints included post-30-day OS, relapse-free survival (RFS), and incidence of second cancers.

RESULTS

APL occurred in 374 males and 387 females at a median age of 44 (1-97) years. Annual incidences increased progressively, averaging 0.32 per 100,000 people. All-trans retinoic acid (ATRA)-based and oral-ATO-based regimens were used in 469 and 282 patients. There were 144 EDs, occurring almost exclusively in ATRA-based inductions (N = 139), being more with males, age > 50 years, leucocyte > 10 × 10⁹/L, diagnosis during 1991-2009 and fewer with oral-ATO-based regimens. After a median of 75 (interquartile range: 14-161) months, 5-year and 10-year OS were 68.1% and 63.3%, inferior with males, age > 50 years, leucocyte > 10 × 10⁹/L, high-risk Sanz score and superior with oral-ATO-based regimens. Factoring out EDs, 5-year and 10-year post-30-day OS were 84.0% and 78.1%, inferior with males and superior with oral-ATO-based regimens. In 607 CR1 patients, the 5-year RFS was 83.8%, superior with diagnosis in 2010-2021 and oral-ATO-based regimens. Second cancers developed in 21 patients, unrelated to oral-ATO-based regimens.

CONCLUSIONS

There was an increasing incidence of APL, and all survivals were superior with the use of oral-ATO-based regimens. This study formed part of the Acute Promyelocytic Leukaemia Asian Consortium Project (ClinicalTrials.gov identifier: NCT04251754).

At What Point Are Long-Term (>5 Years) Survivors of APL Safe? A Study from the SEER Database

BACKGROUND

Acute promyelocytic leukemia (APL) is a highly curable cancer, but it is not clear whether it is also necessary to monitor long-term toxicity in "cured" patients who survive for more than five years, which is critical to ensuring maximum survival in APL patients.

METHODS

A total of 1952 APL 5-year survivors and 5973 non-APL acute myeloid leukemia (AML) 5-year survivors were included from the Surveillance, Epidemiology, and End Results (SEER) database. The standardized mortality ratio (SMR) was calculated to measure the risk of death. Cumulative mortality is calculated as the incidence of specific causes of death under competing risk events.

RESULTS

The SMR of all causes of death in >5-year survivors of APL was higher than that of the general population only at 60-119 months (SMR, 1.41). This was mainly because a significant increase in mortality from AML (SMR, 87.67) and second malignant neoplasms (SMNs) (SMR, 1.56) was found only at 60-119 months. However, there was no higher risk of death from non-cancer-related disease in >5-year survivors of APL than that of the general population (SMR, 0.89). The SMR of all-cause deaths in >5-year survivors of non-APL AML decreased year by year and was no higher than that of the general population until after 216 months. The cumulative incidence of AML-related death, SMN-related death, and non-cancer-related death was significantly lower in APL patients than in non-APL AML patients throughout the follow-up period.

CONCLUSIONS

Compared with the general population, the risk of death of patients with APL was higher within 5 to 10 years but not higher over 10 years. Therefore, we believe that long-term survivors of APL are safe after 10 years.

The characteristics and long-term outcomes of acute promyelocytic leukemia patients with early intracranial hemorrhage

Intracranial hemorrhage (ICH) is a major cause of early death (ED) and leads to poor prognosis in acute promyelocytic leukemia (APL). We retrospectively described 27 unselected APL patients who experienced early ICH. The ED rate was 37%. The 3-year overall survival (OS) rate was 45.4%, while the 3-year OS rate of patients who survived through induction therapy was 87.5%. No patient experienced central nervous system leukemia (CNSL). Concurrent differentiation syndrome, white blood cell count, prothrombin time and D-dimer were related to death. Although the ED rate among APL patients with early ICH was high, patients with early ICH had a favorable outcome after surviving through induction therapy. CNSL was rare despite a history of ICH during induction therapy. Compared with APL patients without ICH, it seems unnecessary to administer additional measures to prevent CNSL for this subpopulation in the era of all-trans retinoic acid and arsenic trioxide, but this needs further validation in prospective trials.

The recognition of oral manifestations of haematological disease saves lives: a case report

BACKGROUND

Acute Leukaemias are haematological disorders characterised by the proliferation of immature white blood cells in the bone marrow and/or peripheral blood. Oral manifestations of leukaemia are common and may be the first sign of the disease. The clinical presentation of these Acute Leukaemias may include neutropenic sepsis, hyperviscocity and coagulopathy which confer a potential morbidity and mortality. Clinicians must be able to recognise this pattern of presentation.

CASE REPORT

We report a 34-year-old female who was referred to the Oral and Maxillofacial Surgery department with acute dental pain and pericoronitis. She subsequently had a simple dental extraction but re-presented with a bleeding socket that did not respond to local treatment. Investigation of this led to a diagnosis of Acute Promyelocytic Leukemia (APL). She was admitted under the care of the haematology team for urgent, life-saving, treatment.

CONCLUSIONS

Early diagnosis and treatment of the Acute Leukaemias can be life saving. The oral manifestations of disease are common and may be the first sign. Clinicians must be able to recognise this pattern of presentation and arrange urgent investigation and specialist management.

CLINICAL/CPD RELEVANCE

This case report discusses leukaemia and highlights the important role General Dental Practitioners can play in early diagnosis. We frame a safe approach to managing these patients in a typical case. Whilst this disease subtype is rare, the learning points can be universally applied.

p53 as a unique target of action of cisplatin in acute leukaemia cells

Acute promyelocytic leukaemia (APL) occurs in approximately 10% of acute myeloid leukaemia patients. Arsenic trioxide (ATO) has been for APL chemotherapy, but recently several ATO-resistant cases have been reported worldwide. Cisplatin (CDDP) enhances the toxicity of ATO in ovarian, lung cancer, chronic myelogenous leukaemia, and HL-60 cells. Hence, the goal of this study was to investigate a novel target of CDDP action in APL cells, as an alternate option for the treatment of ATO-resistant APL patients. We applied biochemical, molecular, confocal microscopy and advanced gene editing (CRISPR-Cas9) techniques to elucidate the novel target of CDDP action and its functional mechanism in APL cells. Our main findings revealed that CDDP activated p53 in APL cells through stress signals catalysed by ATM and ATR protein kinases, CHK1 and CHK2 phosphorylation at Ser 345 and Thr68 residues, and downregulation and dissociation of MDM2-DAXX-HAUSP complex. Our functional studies confirmed that CDDP-induced repression of MDM2-DAXX-HAUSP complex was significantly reversed in both nutilin-3-treated KG1a and p53-knockdown NB4 cells. Our findings also showed that CDDP stimulated an increased number of promyelocytes with dense granules, activated p53 expression, and downregulated MDM2 in liver and bone marrow of APL mice. Principal conclusion of our study highlights a novel mode of action of CDDP targeting p53 expression which may provide a basis for designing new anti-leukaemic compounds for treatment of APL patients.

Oral Realgar-Indigo Naturalis Formula Treatment for Acute Promyelocytic Leukemia in Children: A Randomized, Control Clinical Trial

Objective

To analyze the efficacy, safety, and economy of RIF compared with intravenous arsenic trioxide (ATO) for the induction and consolidation therapy of pediatric APL.

Materials and Methods

In this randomized control clinical trial (NCT02200978), children with newly diagnosed APL from June 2013 to December 2017 were randomly divided into RIF and ATO groups. The groups were treated with RIF or ATO in combination with all-trans retinoic acid (ARTA) and conventional chemotherapeutic drugs during induction and consolidation therapy.

Results

Ninteen patients were enrolled, including eight in the RIF group and 11 in the ATO group. After induction therapy, the bone marrow morphologic complete remission (CR) rate, the median time to CR, and molecular remission (promyelocytic leukemia protein (PML)/retinoic acid receptor α (RARα) conversion) rates showed no significant differences between patients in the RIF versus ATO groups (100% vs. 100%, p=1.000; 22 vs. 24 days, p=0.395; 28.5% vs. 54.5%, p=0.367, resp.). After consolidation therapy, the molecular remission rate was 100% in both groups. At the end of more than two years of follow-up, the disease-free survival (DFS) rate was 100% in both groups.

Conclusion

Oral RIF can achieve similar efficacy to intravenous ATO for APL in children with good safety, less toxicity, fewer side effects, and fewer inpatient days. Therefore, oral RIF can be used as an alternative to intravenous ATO for the treatment of APL in children.

Relationship between leukaemic stem cells and hematopoietic stem cells and their clinical application

The world is aging and with it an associated increase in malignancies. Haematological malignancies especially Acute Myeloid Leukemia (AML) are no exception to this trend. With scientific advances, development of new AML treatments has improved patient mortality. One future research interest would be Leukeamic Stem Cells (LSC). This review aims to briefly highlight main LSC characteristics and their relationship with hematopoietic stem cells. Key LSC characteristics include dysregulated apoptosis, capacity for self-renewal, genomic instability, dysregulated energetics, immune privilege and an altered tumor microenvironment. Similar characteristics are also found in HSCs though in a regulated form. Classifying these characteristics will aid in the development of clinical biomarkers for LSC which is a potential clinical application of LSC biology. LSC biomarkers might prove to be critical in future AML management through improving accuracy of AML diagnosis, providing targeted treatment to minimize side effects, refinement of prognosis and relapse risk for earlier intervention.

Clinical Availability of ATRA for Patients With Suspected Acute Promyelocytic Leukemia: Why Guidelines May Not Be Followed

BACKGROUND

All-trans retinoic acid (ATRA) serves as the backbone of the management of patients with acute promyelocytic leukemia (APL), with guidelines recommending the initiation of ATRA as soon as APL is suspected. As a regional referral center for patients with acute leukemia, those who are suspected of having APL are often transferred to our facility. However, many referring centers are unable to initiate treatment using ATRA. We conducted an exploratory analysis of the clinical availability of ATRA and the factors limiting access to this critical drug.

PATIENTS AND METHODS

The United States was divided into 6 geographic regions: Northwest, Southwest, Central, Southeast, Northeast, and the Great Lakes. Twenty hospitals were randomly selected from states within each of these regions and were surveyed as to whether they typically treated patients with acute leukemia, the availability of ATRA at their institution, and reported reasons for not stocking ATRA (if not available).

RESULTS

Less than one-third of hospitals queried (31%) had ATRA in stock. Neither the size of the hospital nor the hospital's status as academic versus nonacademic (53% vs 31%; P=.08) influenced ATRA availability. Of the hospitals that referred patients with APL, only 14% (7/49) had ATRA readily available. Hospitals that treated patients with APL were more likely to have ATRA available than referring centers (58% vs 14%; P=.000002).

CONCLUSIONS

Nearly two-thirds of the hospitals surveyed that cared for patients with acute leukemia do not have ATRA immediately available. Moreover, the vast majority of hospitals that refer patients to other centers do not have ATRA. These findings should spur investigation into the impact of immediate ATRA availability on the morbidity and mortality of patients with APL. A call by hematologists nationwide to their formulary committees is warranted to ensure that this lifesaving medication is available to patients suspected of having APL.

Early mortality and overall survival in acute promyelocytic leukemia: do real-world data match results of the clinical trials?

Acute promyelocytic leukemia (APL) boasts overall survival (OS) of >90% at 3 years and early mortality of <5% in recent clinical trials. Using a large National Cancer Database, we performed analysis of 7190 adults with APL to determine whether one-month mortality and OS of patients with APL treated in real-world practices mirror outcomes noted in clinical trials. Only 64% of total patients received multi-agent therapy; 32% received either single-agent therapy or no therapy at all. One-month mortality was 6% for patients ≤18 years, 6% for 19-40 years, 10% for 41-60 years, and 21% for >60 years. OS at 1- and 3-year were 81% and 75%, respectively. In a multivariate analysis, age ≤ 40 years, treatment at academic center, use of multi-agent therapy, and diagnosis after 2009 conferred better OS. In this largest database study in APL till date, we demonstrated an overall improvement in OS over time but challenges still exist in translating successes of clinical trials to real-world practices.

Characteristics and predictors of early hospital deaths in newly diagnosed APL: a 13-year population-wide study

Despite therapeutic advances, early death (ED) remains a major factor curtailing survival of acute promyelocytic leukemia (APL). Studies examining factors that cause early death (ED; within 30 days of admission) and the correlation of survival with the timing of administration of all-trans retinoic acid (ATRA) and hemostatic parameters are scarce. We performed a cohort analysis of nonselect patients with newly diagnosed APL who presented to the health care system in Hong Kong, where oral arsenic trioxide was used. From 1 January 2007 to 30 April 2020, 358 patients (median age, 47 [1-97] years) with newly diagnosed APL were identified. ED occurred in 56 patients (16%): 11 (3%) died in the first 2 days after admission (intracranial hemorrhage [ICH], n = 6; APL-differentiation syndrome [APL-DS], n = 4; infection, n = 1); 22 (6%) died within 3 to 7 days (ICH, n = 12; APL-DS, n = 8; infections, n = 2), and 23 (6%) died within 8 to 30 days (ICH, n = 7; APL-DS, n = 11; infection, n = 5). Factors significantly associated with ED by multivariate analysis included male sex (P = .01); presenting leukocyte count ≥10 × 109/L (P = .03); fibrinogen <1.5 g/L (P = .02); and ATRA administration >24 hours after hospital admission (P < .001). After a median follow-up of 47 (0-166) months, the 5- and 10-year overall survival (OS) was 68.6% and 61.2%, respectively. Excluding EDs, the 5- and 10-year post-30-day OS improved to 81.3% and 72.5%. Early administration of ATRA (<24 hours) and vigorous correction of hemostatic abnormalities, including hypofibrinogenemia, are key to reducing ED.

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.

Efficacy and the Adverse Effects of Oral Versus Intravenous Arsenic for Acute Promyelocytic Leukemia: A Meta-Analysis of Randomized-Controlled Studies

Acute promyelocytic leukemia, a subtype of acute myeloid leukemia, is highly curable. In subgroup of patients with non-high-risk acute promyelocytic leukemia, intravenous arsenic trioxide plus all-trans-retinoic acid is considered the preferred regimen for acute promyelocytic leukemia. Recently, there are interests in the use of the oral form of arsenic, named the Realgar-Indigo naturalis formula, but the data on its efficacy and safety are still relatively limited. The current study was conducted with the aims to identify and summarize the results of all available randomized-controlled studies. A systematic review was conducted in the 2 major databases, utilizing the terms for arsenic and acute promyelocytic leukemia. Eligible studies had to be randomized-controlled studies that compared efficacy and/or adverse effects of oral arsenic versus intravenous arsenic for treatment of patients with acute promyelocytic leukemia. The Mantel-Haenszel method was used to pool the effect estimates and 95% confidence intervals of the included studies together. A total of 4 randomized controlled studies with 482 patients with acute promyelocytic leukemia (258 in Realgar-Indigo naturalis formula group and 224 in intravenous arsenic trioxide group) were included in the meta-analysis. The chances of achieving complete remission were numerically higher in the Realgar-Indigo naturalis formula group but the difference was not statistically significant (pooled odds ratio: 4.59, 95% CI: 0.74-28.57, I² = 0%). Similarly, other efficacy outcomes, including 30-day mortality rate, overall survival, and event-free survival, also tended to favor the Realgar-Indigo naturalis formula group but the difference was not statistically significant. There was no significant difference in the chance of developing differentiation syndrome, cardiac complications, grades 3 to 4 liver toxicity, grades 3 to 4 renal toxicity, and infection between the 2 groups. The results may suggest that all-trans-retinoic acid plus oral Realgar-Indigo naturalis formula regimen is, at minimum, not a worse alternative to the standard all-trans-retinoic acid plus intravenous intravenous arsenic trioxide regimen for treatment of acute promyelocytic leukemia, especially for patients with low-to-intermediate risk.

Second Primary Malignancy after Acute Promyelocytic Leukemia: A Population-Based Study

Acute promyelocytic leukemia (APL), is now highly curable with treatment approaches that include all-trans retinoic acid (ATRA). The high incidence of APL in the Hispanics suggests an association with genetic variants in this population. Information on second primary malignancies (SPMs) in patients with APL is limited. The Surveillance, Epidemiology, and End Results (SEER) database was used to interrogate whether the rate of SPMs in patients with APL was associated with ethnicity and/or ATRA treatment. Between 2000 and 2016, 116 cases of SPM were diagnosed among 4019 patients with APL. The mean age at diagnosis of primary APL was 53.9 years (±15.7 years), and the mean age at diagnosis of SPMs was 59.0 years (±14.5 years). Comparisons with 3774 APL survivors who did not develop SPMs revealed that age ≥40 years at diagnosis of APL (p < 0.001) and non-Hispanic white ethnicity (p = 0.025) were associated with SPMs in APL survivors. Salivary gland, liver, and soft tissue malignancies were significantly more common in patients with primary APL than in individuals with non-APL malignancies. A risk analysis comparing patients who had APL with patients who had non-APL AML suggests that SPMs after APL is associated with ATRA treatment. Therefore, patient follow-up after APL should focus on early diagnosis of SPMs.

PEACE in the midst of an emergency: a rash not to miss

We present the case of a 29-year-old woman who initially presented to her GP with a short history of non-pruritic annular skin lesions with central clearing. A month later, she developed signs and symptoms of bone marrow failure with bruising, epistaxis and fatigue. After urgent review of a blood film, she was diagnosed with acute promyelocytic leukaemia (APML), which is a haematological emergency. Treatment with all-trans retinoic acid (ATRA) was commenced immediately and she was subsequently treated with arsenic trioxide (ATO). The annular rash was subsequently diagnosed as paraneoplastic erythema annulare centrifugum (PEACE), which resolved with treatment. This case demonstrates the importance of the urgent diagnosis of APML and highlights PEACE as a rash that clinicians should be aware of, as it can be the initial manifestation of a number of both haematological and non-haematological malignancies.

Acute Myeloid Leukemia: Advanced Practice Management From Presentation to Cure

Acute myeloid leukemia (AML) is the most common acute leukemia in adults, diagnosed in approximately 21,450 individuals annually in the US with nearly 11,000 deaths attributable to this disease (National Cancer Institute, 2020). Acute myeloid leukemia is a disease of the elderly, with the average age of diagnosis being 68 years old (Kouchkovsky & Abdul-Hay, 2016). It is a heterogeneous disease with widely varying presentations but universally carries a poor prognosis in the majority of those affected. Unfortunately, the 5-year overall survival rate remains poor, at less than 5% in patients over 65 years of age (Thein, Ershler, Jemal, Yates, & Baer, 2013). The landscape of AML is beginning to change, however, as new and improved treatments are emerging. Advanced practitioners (APs) are often involved in the care of these complex patients from the time of initial symptoms through diagnosis, treatment, and potentially curative therapy. It is vitally important for APs to understand and be aware of the various presentations, initial management strategies, diagnostic workup, and treatment options for patients with AML, especially in the elderly population, which until recently had few treatment options. This Grand Rounds article highlights the common presenting signs and symptoms of patients with AML in the hospital, including a discussion of the upfront clinical stability issues, oncologic emergencies, diagnostic evaluation, and current treatment options for elderly patients and those with poor performance status.

An unusual headache: CSF negative APML relapse in the brain

Acute Promyelocytic Leukaemia (APML) is a subtype of Acute Myeloid Leukaemia (AML), responsible for around 10% of cases of the disease in adults. Extra medullary disease (EMD) occurs infrequently in APML, but where EMD does occur, the central nervous system is one of the most commonly infiltrated sites. Our case describes a man in his 40s undergoing post-therapy surveillance for APML who presented to follow-up clinic with a headache, which was ultimately found to be caused by a tumour comprised of APML cells. His case presented a diagnostic challenge due to the benign appearances of the lesion on initial computed tomography brain imaging and the non-diagnostic cerebrospinal fluid analysis. The diagnostic difficulties described in our case emphasizes that clinicians working with APML patients must approach new neurological symptoms with a high degree of suspicion to prevent diagnostic delay.

Protein Kinase C Alpha (PKCα) overexpression leads to a better response to retinoid acid therapy through Retinoic Acid Receptor Beta (RARβ) activation in mammary cancer cells

PURPOSE

Retinoids have proved to be effective for hematologic malignancies treatment but till nowadays, their use as single agent for the solid tumor's management is still controversial. All-trans retinoic acid (ATRA), the main active metabolite of vitamin A, exerts non-genomic interactions with different members of the protein kinase C (PKC) family, recognized modulators of different tumor progression pathways. To determine whether a group of patients could become benefited employing a retinoid therapy, in this study we have evaluated whether PKCα expression (a poor prognosis marker in breast cancer) could sensitizes mammary cells to ATRA treatment.

METHODS

PKCα overexpression was achieved by stable transfection and confirmed by western blot. Transfected PKC functionality was determined by nuclear translocation-induction and confocal microscopy. In vitro proliferation was evaluated by cell counting and cell cycle distribution was analyzed by flow cytometry. In vivo studies were performed to evaluate orthotopic tumor growth and experimental lung colonization. Retinoic acid response elements (RARE) and AP1 sites-dependent activity was studied by gene reporter assays and retinoic acid receptors (RARs) were measured by RT-qPCR.

RESULTS

Our findings suggest that high PKCα levels improve the differentiation response to ATRA in a RAR signaling-dependent manner. Moreover, RARβ expression appears to be critical to induce ATRA sensitization, throughout AP1 trans-repression.

CONCLUSION

Here we propose that retinoids could lead a highly personalized anticancer treatment, bringing benefits to patients with aggressive breast tumors resulting from high PKCα expression but, an adequate expression of the RARβ receptor is required to ensure the effect on this process.

Trisenox Disrupts MDM2-DAXX-HAUSP Complex and Induces Apoptosis in a Mouse Model of Acute Leukemia

Trisenox (TX) is successfully used for both de novo and relapsed acute promyelocytic leukemia (APL) treatment. Although TX toxicity to APL cells is mediated by oxidative stress, DNA damage, cell cycle arrest, and apoptosis, its mode of action in the transgenic mice model of APL is poorly understood. We hypothesized that TX regulates cell cycle and apoptosis in APL mice by p53 activation, DNA damage, and reduced expression of MDM2-DAXX-HAUSP complex. To test hypothesis, we treated APL mice with different doses (0, 1.25.2.5.5.0 & 7.5 mg/kg body wt) of TX and collected the liver and bone marrow cells. We applied several techniques to check the expression of PML-RARα, complex molecules, and DNA damage in APL mice bone marrow cells and liver. Our findings indicate that TX reduced the expression of PML-RARα and complex molecules, induced DNA damage and activated p53 leading to cell cycle arrest and apoptosis in APL mice liver. We found that TX promoted more promyelocytes formation with dense granules in bone marrow cells. It also transmitted the DNA damage signal through protein kinase (ATM & ATR) leading to disruption of complex and activation of p53 in APL mice liver. TX induced cell cycle arrest through activation of p53, p21, and reduced expression of cyclin D1 and cyclin dependent kinases (CDK 2, 4 & 6) in mice liver. It also caused apoptosis through upregulation of caspase 3 and Bax expression, and down-regulation of Bcl2 expression. Taken together, these molecular targets provide new insights into TX mode of action in APL mice.

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.

Oral arsenic trioxide, all-trans retinoic acid, and ascorbic acid maintenance after first complete remission in acute promyelocytic leukemia: Long-term results and unique prognostic indicators

BACKGROUND

The role of arsenic trioxide (As₂ O₃ ) in the maintenance of first complete remission (CR1) in acute promyelocytic leukemia (APL) is unclear.

METHODS

A total of 129 consecutive adult patients with APL of all risk categories who achieved CR1 with conventional induction (all-trans retinoic acid [ATRA]/daunorubicin) and consolidation (daunorubicin/cytarabine [induction daunorubicin and consolidation omitted for age ≥70 years]) underwent maintenance comprising ATRA (45 mg/m² /day), oral As₂ O₃ (10 mg/day), and ascorbic acid (1 g/day) (AAA) for 2 weeks every 2 months for 2 years.

RESULTS

Over a 17-year period from August 1, 2002, to July 31, 2019, 63 men and 66 women (median age, 46 years [range, 18-82 years]) received AAA maintenance, which was already completed in 117 patients. At a median follow-up of 100 months (range, 8-215 months), 17 patients (13%) developed first relapse (R1) (hematologic, n = 14; molecular, n = 3) after a median of 19 months (range, 7-96 months) from CR1. Two R1 patients had concomitant central nervous system (CNS) involvement. All patients achieved CR2 with oral As₂ O₃ -based salvage. Five patients had a subsequent relapse and died. Eight patients died of unrelated causes while still in CR1. The 5-year and 10-year rates of relapse-free survival (RFS) were 89% and 85%, respectively. The 5-year and 10-year rates of overall survival (OS) were 94% and 87%, respectively. Multivariate analysis showed that inferior RFS was associated with FLT3-ITD (P = .005) and CNS involvement on presentation (P = .004), and inferior OS was associated with therapy-related APL (P = .03), FLT3-ITD (P = .03), and relapse (P = .03). The safety profile was favorable, with no grade 3/4 organ toxicities.

CONCLUSION

CR1 maintenance with AAA is safe and results in favorable long-term survival in patients with APL.

Inhibition of UBE2L6 attenuates ISGylation and impedes ATRA-induced differentiation of leukemic cells

Ubiquitin/ISG15‐conjugating enzyme E2L6 (UBE2L6) is a critical enzyme in ISGylation, a post‐translational protein modification that conjugates the ubiquitin‐like modifier, interferon‐stimulated gene 15 (ISG15), to target substrates. Previous gene expression studies in acute promyelocytic leukemia (APL) cells showed that all‐trans‐retinoic acid (ATRA) altered the expression of many genes, including UBE2L6 (200‐fold) and other members of the ISGylation pathway. Through gene expression analyses in a cohort of 98 acute myeloid leukemia (AML) patient samples and in primary neutrophils from healthy donors, we found that UBE2L6 gene expression is reduced in primary AML cells compared with normal mature granulocytes. To assess whether UBE2L6 expression is important for leukemic cell differentiation—two cell line models were employed: the human APL cell line NB4 and its ATRA‐resistant NB4R counterpart, as well as the ATRA‐sensitive human AML HL60 cells along with their ATRA‐resistant subclone—HL60R. ATRA strongly induced UBE2L6 in NB4 APL cells and in ATRA‐sensitive HL60 AML cells, but not in the ATRA‐resistant NB4R and HL60R cells. Furthermore, short hairpin (sh)RNA‐mediated UBE2L6 depletion in NB4 cells impeded ATRA‐mediated differentiation, suggesting a functional role for UBE2L6 in leukemic cell differentiation. In addition, ATRA induced ISG15 gene expression in NB4 APL cells, leading to increased levels of both free ISG15 protein and ISG15 conjugates. UBE2L6 depletion attenuated ATRA‐induced ISG15 conjugation. Knockdown of ISG15 in NB4 APL cells inhibited ISGylation and also attenuated ATRA‐induced differentiation. In summary, we demonstrate the functional importance of UBE2L6 in ATRA‐induced neutrophil differentiation of APL cells and propose that this may be mediated by its catalytic role in ISGylation.

Hematopoietic stem cell transplantation for pediatric acute promyelocytic leukemia in Japan

BACKGROUND

The number of hematopoietic stem cell transplantation (HSCT) procedures performed for pediatric acute promyelocytic leukemia (APL) has decreased in the all-trans retinoic acid (ATRA) era. Although HSCT is still widely adopted as part of salvage therapy for relapsed patients, there is no general consensus about the optimal transplant type (autologous [auto-HSCT] or allogeneic HSCT [allo-HSCT]).

PROCEDURES

We retrospectively reviewed the clinical data of 95 childhood APL patients who underwent their first HSCT between 1990 and 2014. Of the 95 patients, 40 (42%), 41 (43%), and 3 (3%) underwent HSCT procedures after achieving their first complete remission (CR1), CR2, and CR3, respectively, and 11 (12%) underwent HSCT while in a non-CR state.

RESULTS

The non-CR group exhibited significantly worse five-year overall survival (5yOS) and disease-free survival (5yDFS) (5yOS: 46%; 5yDFS: 46%) than the CR1 (5yOS: 80%; 5yDFS: 78%) and CR2 + CR3 groups (5yOS: 81%; 5yDFS: 76%) (P = 0.013 and P < 0.01, respectively). Of the patients treated in CR2, no significant differences in 5yOS or the five-year cumulative incidence of relapse (5yRI) were detected between the auto-HSCT and allo-HSCT groups (5yOS: 85%, vs 78%, P = 0.648; 5yRI: 9%, vs 11%, P = 0.828). Among the patients who underwent allo-HSCT in CR2, those with matched sibling donors displayed a significantly higher 5yRI (33%) than those with other types of donors (0%, P = 0.015).

CONCLUSIONS

Even after relapsing, childhood APL can be cured with HSCT if CR is achieved. These findings demonstrate that achieving CR followed by HSCT is the preferred strategy for treating children with relapsed or refractory APL.

How I treat acute myeloid leukemia in the era of new drugs

The acute myeloid leukemia (AML) treatment landscape has changed substantially since 2017. New targeted drugs have emerged, including venetoclax to target B-cell lymphoma 2, midostaurin and gilteritinib to target FLT3, and ivosidenib and enasidenib to target mutant isocitrate dehydrogenase 1 and 2, respectively. Other additions include reapproval of gemtuzumab ozogomycin to target CD33, glasdegib to target the hedgehog pathway, and a liposomal formulation of daunorubicin and cytarabine (CPX-351). Genomically heterogeneous AML has a tendency to evolve, particularly under selective treatment pressure. For decades, treatment decisions have largely centered around chemotherapy drug intensity. Physicians now have access to an increasing number of drugs with novel mechanisms of action and distinctive side-effect profiles. Key issues faced by hematologists in this era of new drugs include (1) the timely identification of actionable mutations at diagnosis and at relapse; (2) deciding which drug to use among several therapeutic options; and (3) increasing awareness of how to anticipate, mitigate, and manage common complications associated with these new agents. This article will use 3 case presentations to discuss some of the new treatment challenges encountered in AML management, with the goal of providing practical guidance to aid the practicing physician.

Myeloid sarcoma of the tongue as a first manifestation of acute promyelocytic leukemia: A case report

Introduction

We describe a 35-year-old male patient showing a myeloid sarcoma (MS) of the tongue as the first manifestation of acute promyelocytic leukemia (APL). The MS can appear in all parts of the human body, but it is extremely rare in the tongue.

Clinical case

The main symptoms were a pain in the tongue, asthenia, gingivorrhagia, fever. We found a tumor in the tongue, which was irregular in size and located in the posterior region of the right lateral edge of the tongue. The diagnosis of MS was made by the anatomopathological and immunohistochemical study, while the definite diagnosis of APL was confirmed by the molecular test. The treatment of APL was based on the administration of trans-retinoic acid 45 mg/m² daily continuously and daunorubicin 60 mg/m² every other day for 4 doses, with a favorable therapeutic response to APL and MS.

Conclusion

Promyelocytic myeloid cells can infiltrate many organs extramedullary, such as the tongue, and this might precede bone marrow infiltration. The early identification of myeloid sarcoma allows to carry out an early treatment of the APL.

Central Nervous System Double Relapse of Acute Promyelocytic Leukemia and Acute Myelomonocytic Leukemia

Relapse of acute promyelocytic leukemia (APL) and non-M3-acute myeloid leukemia in the central nervous system (CNS) are rare events. Here, we describe a case of simultaneous relapses of APL and acute myelomonocytic leukemia on the CNS of a patient after allogeneic bone marrow transplant. This extremely unusual case highlights the difficulties that CNS leukemia relapses pose in the post-transplant setting.

PPARγ Agonists in Combination Cancer Therapies

Peroxisome proliferator-activated receptor-gamma (PPARγ) is a nuclear receptor acting as a transcription factor involved in the regulation of energy metabolism, cell cycle, cell differentiation, and apoptosis. These unique properties constitute a strong therapeutic potential that place PPARγ agonists as one of the most interesting and widely studied anticancer molecules. Although PPARγ agonists exert significant, antiproliferative and tumoricidal activity in vitro, their anticancer efficacy in animal models is ambiguous, and their effectiveness in clinical trials in monotherapy is unsatisfactory. However, due to pleiotropic effects of PPARγ activation in normal and tumor cells, PPARγ ligands interact with many antitumor treatment modalities and synergistically potentiate their effectiveness. The most spectacular example is a combination of PPARγ ligands with tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia (CML). In this setting, PPARγ activation sensitizes leukemic stem cells, resistant to any previous form of treatment, to targeted therapy. Thus, this combination is believed to be the first pharmacological therapy able to cure CML patients. Within the last decade, a significant body of data confirming the benefits of the addition of PPARγ ligands to various antitumor therapies, including chemotherapy, hormonotherapy, targeted therapy, and immunotherapy, has been published. Although the majority of these studies have been carried out in vitro or animal tumor models, a few successful attempts to introduce PPARγ ligands into anticancer therapy in humans have been recently made. In this review, we aim to summarize shines and shadows of targeting PPARγ in antitumor therapies.

Myeloid maturation potentiates STAT3-mediated atypical IFN-γ signaling and upregulation of PD-1 ligands in AML and MDS

Interferon (IFN)-γ is the major mediator of anti-tumor immune responses; nevertheless, cancer cells use intrigue strategies to alter IFN-γ signaling and avoid elimination. Understanding the immune regulatory mechanisms employed by acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) cells upon exposure to IFN-γ is critical for development of immunotherapy and checkpoint blockade therapy approaches. This study aims to explore the influence of myeloid maturation on IFN-γ-induced PD-L1 and PD-L2 expression and on pro-leukemogenic transcription factor STAT3 signaling in AML and MDS. Stimulation of myeloid blasts’ maturation by all-trans retinoic acid (ATRA) or 1α,25-dihydroxyvitamin D3 (vitamin D) increased the CD11b⁺ fraction that expressed PD-1 ligands in response to IFN-γ. Intriguingly, STAT3 pathway was potently induced by IFN-γ and strengthened upon prolonged exposure. Nonetheless, STAT3-mediated atypical IFN-γ signaling appeared as a negligible factor for PD-L1 and PD-L2 expression. These negative influences of IFN-γ could be alleviated by a small-molecule inhibitor of STAT3, stattic, which also inhibited the upregulation of PD-L1. In conclusion, induction of myeloid maturation enhances the responsiveness of AML and MDS cells to IFN-γ. However, these malignant myeloid cells can exploit both STAT3 pathway and PD-1 ligands to survive IFN-γ-mediated immunity and maintain secondary immune resistance.

Oral arsenic trioxide incorporation into frontline treatment with all-trans retinoic acid and chemotherapy in newly diagnosed acute promyelocytic leukemia: A 5-year prospective study

BACKGROUND

Strategies using oral arsenic trioxide (As₂ O₃ ) are efficacious in relapsed acute promyelocytic leukemia (APL), but they have not been examined in newly diagnosed cases.

METHODS

Sixty-two consecutive patients (24 men and 38 women) with a median age of 52 years (range, 22-85 years), 36% of whom had high-risk features, underwent induction with all-trans retinoic acid at 45 mg/m² /d, oral As₂ O₃ at 10 mg/d, and ascorbic acid at 1 g/d (the all-trans retinoic acid-arsenic trioxide-ascorbic acid [AAA] regimen) for 6 weeks (with patients younger than 70 years additionally receiving daunorubicin at 50 mg/m² /d × 3); they then underwent consolidation with 2 monthly cycles of daunorubicin (50 mg/m² /d × 2) and cytarabine (100 mg/m² /d × 5) and received AAA maintenance (2 weeks every 8 weeks) for 2 years. A contemporaneous cohort of 37 newly diagnosed patients (15 men and 22 women) with a median age of 51 years (range, 23-78 years), not consenting to oral As₂ O₃ induction but receiving similar induction, consolidation, and AAA maintenance, served as a comparator group; 46% of these patients had high-risk features.

RESULTS

The oral As₂ O₃ induction cohort showed a complete remission (CR) rate of 100%. After a median of 37 months (range, 13-82 months), there were no relapses, so conventional risks (age, leukocyte and platelet counts, and Fms-like tyrosine kinase 3 [FLT3] mutations) were not relevant. The leukemia-free survival (LFS) and overall survival (OS) rates were 100% at 3 years and 94.1% at 5 years. The non-As₂ O₃ induction cohort showed a CR rate of 100%. After a median of 52 months (range, 14-77 months), there were 3 relapses (8%). Comparable patients in the oral As₂ O₃ induction and non-As₂ O₃ induction cohorts showed similar OS, but LFS was significantly superior in the oral As₂ O₃ induction cohort.

CONCLUSIONS

The incorporation of oral As₂ O₃ into induction for newly diagnosed APL was safe and decreased relapses.

Predictors of early hemorrhage in acute promyelocytic leukemia

Fatal hemorrhage is the most common cause of induction failure and death among patients with acute promyelocytic leukemia (APL). However, there remains no established means of hemorrhagic risk stratification in APL. In this single center retrospective study of 43 patients treated for APL group-based trajectory modeling was used to identify laboratory trends associated with major bleeding. Bleeding risk was significantly associated with particular trends in white blood cell count (WBC) and lactate dehydrogenase level (LDH). Specifically, patients who presented with high WBC and/or LDH, and whose WBC and/or LDH then proceeded to uptrend during the initial days of induction, were significantly more likely to experience major bleeding (p = .0111 and p = .0143, respectively). Additionally, there appeared to be a temporal association between WBC and LDH trends and major bleeding events. Among nonlaboratory variables, differentiation syndrome (DS) was significantly associated with major bleeding (p = .00149).

Hematological Malignancies and Arterial Thromboembolism

Established guidelines exist for prevention and treatment of venous thromboembolism in hematological malignancies, but none for arterial thromboembolism. However, arterial and venous thromboembolism share the same provoking features—including altered procoagulant factors and defective fibrinolytic system. The morbidity for arterial thromboembolism is increasing in hematological malignancies, with the advent of immunomodulatory and targeted therapy. However, survival rate for hematological malignancy is improving. Consequently, as patients with hematological malignancies live longer, comorbidities including diabetes, hypertension and dyslipidemia, may accentuate arterial thrombosis. Thus far, the scientific literature on prophylaxis and treatment for arterial thromboembolism in hematological malignancies is limited. This review highlights the pathogenesis, incidence and clinical features of arterial thromboembolism in hematological malignancies.

Pain in patients with newly diagnosed or relapsed acute leukemia

PURPOSE

Acute leukemia (AL) is associated with substantial morbidity and mortality. We assessed the prevalence and correlates of pain in patients with newly diagnosed or relapsed AL.

METHODS

Patients with newly diagnosed or relapsed AL admitted to a comprehensive cancer center completed the Memorial Symptom Assessment Scale (MSAS), which assesses prevalence, severity, and distress associated with pain and other symptoms. Factors associated with severe pain were assessed using logistic regression. Two raters completed chart reviews in duplicate for patients with severe pain (MSAS severity ≥ 3/4) to determine the site of pain.

RESULTS

Three hundred eighteen patients were recruited from January 2008 to October 2013: 245 (77.0%) had acute myeloid or acute promyelocytic leukemia (AML/APL) and 73 (23.0%) had acute lymphoblastic leukemia (ALL); 289 (90.9%) were newly diagnosed and 29 (9.1%) had relapsed disease. Pain was reported in 156/318 (49.2%), of whom 55/156 (35.3%) reported severe pain (≥ 3/4). Pain was associated with all psychological symptoms (all p < 0.005) and some physical symptoms. Severe pain was associated with younger age (p = 0.02), worse performance status (p = 0.04), ALL diagnosis (p = 0.04), and time from onset of chemotherapy (p = 0.03), with pain peaking at 4 weeks after chemotherapy initiation. The most common sites of severe pain were oropharynx (22; 40%), head (12; 21.8%), and abdomen (11; 20%). Only 3 patients (0.9%) were referred to the symptom control/palliative care team during the month prior to or following assessment.

CONCLUSIONS

Pain is frequent, distressing, and predictable in patients undergoing induction chemotherapy for AL. Further research is needed to assess the efficacy of early supportive care in this population.

Acute promyelocytic leukaemia presenting as necrotising fasciitis of the perineum (Fournier gangrene)

We present a case of an unusual presentation of acute promyelocytic leukaemia (APML), which presented with Fournier gangrene (FG). A 38-year-old man presented with malaise, groin swelling, anal bleeding, fever and was found to have FG. Initial workup revealed pancytopaenia, borderline low fibrinogen, prolonged international normalized ratio (INR), which raised the suspicion for leukaemia. The peripheral blood differential revealed leucopaenia with absolute neutropaenia and a 5% abnormal promyelocytes but no blasts, suspicious for APML. Bone marrow biopsy was performed and fluorescence in situ hydridization (FISH), karyotype and PCR confirmed a t(15;17) translocation, establishing a diagnosis of APML. After 1 month of therapy for intermediate risk APML with All-trans retinoic acid (ATRA) and arsenic trioxide (ATO), repeat chromosomal analysis and repeat bone marrow biopsy revealed no evidence of residual APML. After the consolidation phase was started with ATRA and ATO regimen, the wound healed after 2 months and the patient achieved complete remission.

Cytotoxic therapy in acute myeloid leukemia: not quite dead yet

Given the recent approvals of new agents for acute myeloid leukemia (AML), a clinical trial pipeline stocked with novel therapies, and the rapid integration of imaginative approaches in diseases like acute lymphocytic leukemia and chronic lymphocytic leukemia, it is reasonable to ask whether treatment of AML might finally depart from the classical cytotoxic induction therapy that has been employed since the 1970s. However, for better or worse, in 2018, cytotoxic induction regimens remain the standard of care for most patients. Indeed, the future likely lies in combinations of therapies that act with a spectrum of mechanisms. Using a case-based format, this review will outline current treatment expectations for patients according to karyotypic risk and familiarize readers with the basis for common induction choices. Relapsed/refractory disease may be especially amenable to interventions with novel agents or clinical trials; however, there are still some patients who most benefit from intensive chemotherapy. This review will outline risk systems that help the practitioner identify those with the best chances for response and survival. Finally, clinical tools, including geriatric assessments and comorbidity calculators, may help clinicians recognize patients for whom disease risk and comorbidity tip the balance against classical chemotherapy, a frequent challenge for those who treat this devastating disease.