Acute Leukemia Research Articles

Malformation of the endoplasmic reticulum system evolving into giant inclusions and Auer bodies in acute promyelocytic leukemia: an ultrastructural study of 6 cases

ABSTRACT The endoplasmic reticulum（ER）is the largest membranous network serving as a region for protein, lipid and steroid synthesis, transport and storage. Detailed information about ER-cisternae, ER-tubules and rough endoplasmic reticulum (rER) is scarce in human blood cells. This study describes a series of giant inclusions and Auer bodies in promyeloblasts in six patients with acute promyelocytic leukemia (APL), by light microscopy, transmission electron microscopy (TEM) and cytochemical stains. TEM revealed that giant inclusions and pro-Auer bodies were associated with rER and surrounded by tubular structures composed of degenerated or redundant membrane in promyeloblasts, which corresponded with elements of the ER system. This paper reveals that in the promyeloblasts of APL, ER is the source of and transforms progressively into giant inclusions and Auer bodies.

Asparaginase-specific basophil recognition and activation predict Asparaginase hypersensitivity in mice

BackgroundAsparaginase (ASNase) is a crucial part of acute leukemia treatment, but immune responses to the agent can reduce its effectiveness and increase the risk of relapse. Currently, no reliable and validated biomarker predicts ASNase-induced hypersensitivity reactions during therapy. We aimed to identify predictive biomarkers and determine immune cells responsible for anaphylaxis using a murine model of ASNase hypersensitivity.MethodsOur preclinical study uses a murine model to investigate predictive biomarkers of ASNase anaphylaxis, including anti-ASNase antibody responses, immune complex (IC) levels, ASNase-specific binding to leukocytes or basophils, and basophil activation.ResultsOur results indicate that mice immunized to ASNase exhibited dynamic IgM, IgG, and IgE antibody responses. The severity of ASNase-induced anaphylaxis was found to be correlated with levels of IgG and IgE, but not IgM. Basophils from immunized mice were able to recognize and activate in response to ASNase ex vivo, and the extent of recognition and activation also correlated with the severity of anaphylaxis observed. Using a multivariable model that included all biomarkers significantly associated with anaphylaxis, independent predictors of ASNase-induced hypersensitivity reactions were found to be ASNase IC levels and ASNase-specific binding to leukocytes or basophils. Consistent with our multivariable analysis, we found that basophil depletion significantly protected mice from ASNase-induced hypersensitivity reactions, supporting that basophils are essential and can be used as a predictive marker of ASNase-induced anaphylaxis.ConclusionsOur study demonstrates the need for using tools that can detect both IC- and IgE-mediated hypersensitivity reactions to mitigate the risk of ASNase-induced hypersensitivity reactions during treatment.

Post-transplant cyclophosphamide, calcineurin inhibitor, and mycophenolate mofetil compared to anti-thymocyte globulin, calcineurin inhibitor, and methotrexate combinations as graft-versus-host disease prophylaxis post allogeneic stem cell transplantation from sibling and unrelated donors in patients with acute myeloid leukemia: a study on behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

Post-transplant cyclophosphamide plus calcineurin inhibitor (CNI)(tacrolimus or cyclosporine A) plus mycophenolate mofetil (PTCy/TAC or CSA/MMF) and anti-thymocyte globulin plus CNI (tacrolimus or cyclosporine A) plus methotrexate (ATG/TAC or CSA/MTX) are common graft-versus-host disease (GVHD) prophylaxis regimens. We compared the two regimens in patients with acute myeloid leukemia (AML) undergoing allogeneic transplantation from matched siblings or unrelated donors. 402 received PTCy/TAC or CSA/MMF and 5648 received ATG/TAC or CSA/MTX. Patients in the PTCy-based group were younger (48.7 vs. 51.5 years, p = 0.024) and there was a higher frequency of patient cytomegalovirus seropositivity and female donor to male patient combination in this group (77.8% vs. 71.8%, p = 0.009 and 18.4% vs. 14.4%, p = 0.029, respectively). More patients in the PTCy-based group received reduced-intensity conditioning (51.5% vs. 41%, p < 0.0001). No differences were observed in the incidence of acute GVHD grade II-IV and III-IV (21.2% vs. 20.4%, p = 0.92 and 8.1% vs. 6%, p = 0.1) or 2-year total and extensive chronic GVHD (33.7% vs. 30%, p = 0.09 and 10.7% vs. 11.2%, p = 0.81) between the groups. In the multivariate analysis, all transplant outcomes did not differ between the groups. PTCy/CNI/MMF and ATG/CNI/MTX are alternative regimens for GVHD prophylaxis in AML patients.

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.

Recent Advances in Material Technology for Leukemia Treatments.

Leukemia is a widespread hematological malignancy characterized by an elevated white blood cell count in both the blood and the bone marrow. Despite notable advancements in leukemia intervention in the clinic, a large proportion of patients, especially acute leukemia patients, fail to achieve long-term remission or complete remission following treatment. Therefore, leukemia therapy necessitates optimization to meet the treatment requirements. In recent years, a multitude of materials have undergone rigorous study to serve as delivery vectors or direct intervention agents to bolster the effectiveness of leukemia therapy. These materials include liposomes, protein-based materials, polymeric materials, cell-derived materials, and inorganic materials. They possess unique characteristics and are applied in a broad array of therapeutic modalities, including chemotherapy, gene therapy, immunotherapy, radiotherapy, hematopoietic stem cell transplantation, and other evolving treatments. Here, an overview of these materials is presented, describing their physicochemical properties, their role in leukemia treatment, and the challenges they face in the context of clinical translation. This review inspires researchers to further develop various materials that can be used to augment the efficacy of multiple therapeutic modalities for novel applications in leukemia treatment.

Investigates the genetic types of acute lymphoblastic leukemia in full remission Indonesian patients: a cross-sectional analysis

Acute lymphoblastic leukemia (ALL) is most common in children, especially those aged 1–4 years old, and the second most common acute leukemia in adults. The updated International Consensus Classification (ICC) of B-acute lymphoblastic leukemia (B-ALL) and T-acute lymphoblastic leukemia (T-ALL) includes recent clinical, cytogenetic, and molecular data. Transcriptome sequencing (RNA-seq) was performed on 200 bone marrow specimens using TruSeq library preparation and HiSeq 2000/2500 or NovaSeq 6000 sequencers (Illumina). The purpose of this study was to define the frequency of chromosomal abnormalities of ALL patients in adults and children in Indonesian patients after full remission for international collaboration has improved and advanced the diagnosis and treatment of ALL in Indonesia. Our resulting data showed that the most common structural abnormality was t(9;22) in 15% of the patients. The frequency of genetic abnormalities was 69 % and 60% for numerical and/or structural in the B-ALL and T-ALL patients, respectively. The adults had a higher incidence of t(9;22) and a lower incidence of hyperdiploid than children. In conclusion: The results of this study molecular subtypes differ strikingly in their responses to treatment that needs more assessment.

Study of Patterns of Leukaemia in a Tertiary Care Hospital

Introduction: Leukaemia arises from abnormal proliferation of hematopoietic or lymphoid cells, categorized as acute or chronic and originating from lymphoid, myeloid, or mixed lineages. Clinical manifestations result from leukemic cell proliferation and tissue infiltration. Objectives: This study aimed to determine the frequency and clinicopathological profile of leukaemia cases. Material and Methods: A three-year cross-sectional observational study was carried out in the Department of Pathology, Indira Gandhi Medical College, Shimla. Diagnosis of Leukaemia was based on complete blood count, peripheral smear examination, bone marrow analysis and cytochemistry wherever required. Data comprising of patient details, clinical examination and haematological parameters were analysed. Results: A total of 163 leukaemia cases were identified, including 102 (63%) acute and 61(37%) cases of chronic leukaemia. Acute leukaemia consisted of 58 cases of Acute Myeloid Leukaemia (AML), 25 Acute Lymphoblastic Leukaemia (ALL), and 19 undifferentiated leukaemia (UL), while chronic cases comprised 47 Chronic Myeloid Leukaemia (CML) and 14 Chronic Lymphocytic Leukaemia (CLL). Most patients were in the age group of 31-60 years, with a male predominance (M:F 1.7:1). Conclusions: Early diagnosis and typing are vital for prompt leukaemia treatment. Despite advanced technologies, cytomorphological examination with cytochemistry remains crucial, especially in resource-limited settings like India. Keywords: Leukaemia, acute, chronic, cytomorphology, observational study

Differentiation Syndrome Presenting as Acute Kidney Injury in a Patient of Acute Promyelocytic Leukemia on All-trans Retinoic Acid and Arsenic Trioxide Regimen: A Case Report

Introduction: Acute promyelocytic leukemia (APL), classified as Subtype M3 of acute myeloid leukemia, is known for its relatively favorable prognosis, primarily due to the high effectiveness of all-trans retinoic acid (ATRA) in treating the maturation block. However, it is essential to be aware of potential complications such as ATRA syndrome, which can affect 5%–25% of patients and manifest with symptoms such as fever, interstitial pulmonary infiltration, pleural/pericardial effusion, and acute renal failure. Methods: We present the case of a 47-year-old female with a history of hypertension, who experienced rash, fever, and reduced urine output during the induction phase with ATRA. Her serum creatinine levels exhibited a rapid increase from 2.63 mg/dL on October 07, 2022, to 7 mg/dL on October 18, 2022, despite having normal-sized kidneys and normal corticomedullary differentiation. A renal biopsy conducted on October 20, 2022, revealed features consistent with active tubulointerstitial nephritis, with direct immunofluorescence showing no significant glomerular immune deposits. A total of 17 hemodialysis sessions were performed. Results: A subsequent bone marrow examination conducted on October 26, 2022, demonstrated a hypercellular aspirate with normal morphology. However, due to the persistence of renal failure, a repeat biopsy was performed, revealing severe acute tubular injury. Pulse steroids were initiated, and ATRA was discontinued, resulting in an improvement in renal function. Conclusion: This case highlights an instance of acute, early, and severe differentiation syndrome (DS) occurring after induction therapy in a patient with APL. The DS in this case was particularly severe, leading to renal failure necessitating hemodialysis. The prompt initiation of pulse steroids and discontinuation of ATRA proved to be effective in managing this complication. Clinicians should remain vigilant for DS and its potential complications, including acute kidney injury and acute tubulointerstitial nephritis, when treating patients with APL.

Association between Serum Lactate Dehydrogenase Level and 30-day Mortality in Patients with Intracranial Hemorrhage with Acute Leukemia in the Induction Phase: A Cohort Study.

Objectives  This study aimed to identify the association between lactate dehydrogenase (LDH) levels and 30-day mortality in patients with intracranial hemorrhage (ICH) with acute leukemia during the induction phase. Methods  This cohort study included patients with acute leukemia with ICH during induction. We evaluated serum LDH levels upon admission. Multivariable Cox regression analyzed the LDH 30-day mortality association. Interaction and stratified analyses based on factors like age, sex, albumin, white blood cell count, hemoglobin level, and platelet count were conducted. Results  We selected 91 patients diagnosed with acute leukemia and ICH. The overall 30-day mortality rate was 61.5%, with 56 of the 91 patients succumbing. Among those with LDH levels ≥ 570 U/L, the mortality rate was 74.4% (32 out of 43), which was higher than the 50% mortality rate of the LDH < 570 U/L group (24 out of 48) ( p  = 0.017). In our multivariate regression models, the hazard ratios and their corresponding 95% confidence intervals for Log2 and twice the upper limit of normal LDH were 1.27 (1.01, 1.58) and 2.2 (1.05, 4.58), respectively. Interaction analysis revealed no significant interactive effect on the relationship between LDH levels and 30-day mortality. Conclusions  Serum LDH level was associated with 30-day mortality, especially in patients with LDH ≥ 570 U/L.

Deep learning assists in acute leukemia detection and cell classification via flow cytometry using the acute leukemia orientation tube

This study aimed to evaluate the sensitivity of AI in screening acute leukemia and its capability to classify either physiological or pathological cells. Utilizing an acute leukemia orientation tube (ALOT), one of the protocols of Euroflow, flow cytometry efficiently identifies various forms of acute leukemia. However, the analysis of flow cytometry can be time-consuming work. This retrospective study included 241 patients who underwent flow cytometry examination using ALOT between 2017 and 2022. The collected flow cytometry data were used to train an artificial intelligence using deep learning. The trained AI demonstrated a 94.6% sensitivity in detecting acute myeloid leukemia (AML) patients and a 98.2% sensitivity for B-lymphoblastic leukemia (B-ALL) patients. The sensitivities of physiological cells were at least 80%, with variable performance for pathological cells. In conclusion, the AI, trained with ResNet-50 and EverFlow, shows promising results in identifying patients with AML and B-ALL, as well as classifying physiological cells.

IT-ENABLED WGCNA FOR CRITICAL GENE MODULE MAPPING AND THERAPY OPTIMIZATION: ADVANCING LEUKEMIA CARE

Acquiring a profound comprehension of the complex correlation between genes is essential for progressing treatment and diagnostics in acute leukemia research. This work utilizes WGCNA to analyze the gene expression data obtained from 72 patients diagnosed with acute leukemia. This approach has not been widely employed in this particular setting previously. Our first objective was to identify essential gene modules and core genes that could offer a novel insight into the fundamental causes of the disease. To ensure the precision of the gene expression data, a thorough pre-processing is carried out, which includes normalization and quality control techniques. The WGCNA technique produces a gene co-expression network that targets explicitly differentially expressed genes (DEGs). This network is designed primarily to exploit pairwise correlations, as the underlying data is meant to create such a network. The modules identified via hierarchical clustering are assigned distinct colors to aid in recognizing gene expression patterns and associations that may not be readily apparent when examining individual genes in isolation. An essential component of our research involved identifying pivotal genes inside these modules using several centrality metrics, including degree, closeness, and betweenness centralities. These genes are suspected to have a crucial role in starting and progressing acute leukemia. We must mention that genes such as M91438_at and S82362_s_at came out as significant, in line with their centrality in the network analysis. However, it is privileged that these results hold a promise for further validation. The study throws open trails for future research, especially in experimental validation of these genes. These findings indeed have the potential to contribute to the development of targeted therapies and improvement in diagnostic methods, resulting in better patient outcomes in acute leukemia. This study also highlights the applicability of WGCNA towards unraveling leukemia's genomics, underscoring the continued exploration in this critical area of medical research.

First-Line Respiratory Support for Children With Hematologic Malignancy and Acute Respiratory Failure.

To characterize trends in noninvasive ventilation (NIV) and invasive mechanical ventilation (IMV) use over time in children with hematologic malignancy admitted to the PICU with acute respiratory failure (ARF), and to identify risk factors associated with NIV failure requiring transition to IMV. Retrospective cohort analysis using the Virtual Pediatric Systems (VPS, LLC) between January 1, 2010 and December 31, 2019. One hundred thirteen North American PICUs participating in VPS. Two thousand four hundred eighty children 0-21 years old with hematologic malignancy admitted to participating PICUs for ARF requiring respiratory support. None. There were 3013 total encounters, of which 868 (28.8%) received first-line NIV alone (NIV only), 1544 (51.2%) received first-line IMV (IMV only), and 601 (19.9%) required IMV after a failed NIV trial (NIV failure). From 2010 to 2019, the NIV only group increased from 9.6% to 43.1% and the IMV only group decreased from 80.1% to 34.2% (p < 0.001). The NIV failure group had the highest mortality compared with NIV only and IMV only (36.6% vs. 8.1%, vs. 30.5%, p < 0.001). However, risk-of-mortality (ROM) was highest in the IMV only group compared with NIV only and NIV failure (median Pediatric Risk of Mortality III ROM 8.1% vs. 2.8% vs. 5.5%, p < 0.001). NIV failure patients also had the longest median PICU length of stay compared with the other two study groups (15.2 d vs. 6.1 and 9.0 d, p < 0.001). Higher age was associated with significantly decreased odds of NIV failure, and diagnosis of non-Hodgkin lymphoma was associated with significantly increased odds of NIV failure compared with acute lymphoid leukemia. For children with hematologic malignancy admitted to the PICU with ARF, NIV has replaced IMV as the most common initial therapy. NIV failure rate remains high with high-observed mortality despite lower PICU admission ROM.

Lumbosacral Radiculopathy as a Rare Extramedullary Presentation of Recurrent Acute Myelogenous Leukemia (P11-11.003)

Lumbosacral Radiculopathy as a Rare Extramedullary Presentation of Recurrent Acute Myelogenous Leukemia (P11-11.003)

Antifungal treatment duration in hematology patients with invasive mold infections: an untold story

Abstract Background Limited data exist on when and how to stop antifungal treatment (AFT) in immunocompromised patients with invasive mold infections (IMI). Methods This is a retrospective multi-center study on adult patients with acute myelogenous leukemia (AML) and proven/probable IMI (01.01.2010-31.12.2022) in three University Hospitals. The primary objective was to describe AFT duration and adaptation. Secondary objectives were to investigate the reasons for AFT adjustments and prolongation. Results Seventy-one patients with 73 IMI were identified; 51 (71.8%) had an allogeneic hematopoietic cell transplant (HCT). Most infections were invasive aspergillosis (IA, 49/71, 69%), followed by mucormycosis (12, 16.9%), and other IMI (12, 16.9%); there were two mixed infections. Treatment duration was 227 days (IQR:115.5-348.5). There was no difference in AFT duration between patients with IA and non-IA IMI (P:0.85) or by center (P:0.92). Treatment was longer in patients with an allogeneic HCT versus not (P:0.004). Sixteen (22.5%) patients had no therapy modifications. In 55 (77.5%) patients 2 (median; IQR:1-3; range:1,8) changes were observed. There were 182 reasons leading to 165 changes, associated with clinical efficacy (82/182, 44.5%), toxicity (47, 25.8%), and logistical reasons (22, 12.1%); no reason was documented in 32 (18.8%) changes. AFT was continued beyond day-90/day-180 in 59 (83%)/39 (54.9%) patients, respectively, mostly due to persistence of immunosuppression. Conclusions AFT in AML patients with IMI is longer than recommended by guidelines and frequently associated with treatment adjustments due to variable reasons. More data and better guidance are required to optimize AFT duration and secondary prophylaxis administration according to immunosuppression.

Clinicopathological and Immunophenotypic Characteristics of Series of ZNF384 Re-arranged Acute Leukemias

Clinicopathological and Immunophenotypic Characteristics of Series of ZNF384 Re-arranged Acute Leukemias

Essential thrombocythaemia: A contemporary approach with new drugs on the horizon.

Essential thrombocythaemia (ET) is a myeloproliferative neoplasm characterized by an increased risk of vascular complications and a tendency to progress to myelofibrosis and acute leukaemia. ET patients have traditionally been stratified into two thrombosis risk categories based on age older than 60 years and a history of thrombosis. More recently, the revised IPSET-thrombosis scoring system, which accounts for the increased risk linked to the JAK2 mutation, has been incorporated into most expert recommendations. However, there is increasing evidence that the term ET encompasses different genomic entities, each with a distinct clinical course and prognosis. Moreover, the effectiveness and toxicity of cytoreductive and anti-platelet treatments differ depending on the molecular genotype. While anti-platelets and conventional cytoreductive agents, mainly hydroxycarbamide (hydroxyurea), anagrelide and pegylated interferon, remain the cornerstone of treatment, recent research has shed light on the effectiveness of novel therapies that may help improve outcomes. This comprehensive review focuses on the evolving landscape of treatment strategies in ET, with an emphasis on the role of molecular profiling in guiding therapeutic decisions. Besides evidence-based management according to revised IPSET-thrombosis stratification, we also provide specific observations for those patients with CALR-, MPL-mutated and triple-negative ET, as well as cases with high-risk mutations.

Prognostic impact of number of induction courses to attain complete remission in patients with acute myeloid leukemia transplanted with either a matched sibling or human leucocyte antigen 10/10 or 9/10 unrelated donor: An Acute Leukemia Working Party European Society for Blood and Marrow Transplantation study.

For the majority of patients with acute myeloid leukemia (AML) an allogeneic stem cell transplant (SCT) in first complete remission (CR) is preferred. However, whether the number of courses required to achieve CR has a prognostic impact is unclear. It is unknown which factors remain important in patients requiring more than one course of induction to attain remission. This Acute Leukaemia Working Party study from the European Society for Blood and Marrow Transplantation identified adults who received an allograft in first CR from either a fully matched sibling or 10/10 or 9/10 human leucocyte antigen (HLA)-matched unrelated donor (HLA-A, HLA-B, HLA-C, HLA-DR, or HLA-DQ). Univariate and multivariate analyses were undertaken to identify the prognostic impact of one or two courses of induction to attain CR. A total of 4995 patients were included with 3839 (77%) patients attaining a CR following one course of induction chemotherapy (IND1), and 1116 patients requiring two courses (IND2) to attain CR. IND2 as compared to IND1 was a poor prognostic factor in a univariate analysis and remained so in a multivariate Cox model, resulting in an increased hazard ratio of relapse (1.38; 95% confidence interval [CI], 1.16-1.64; p=.0003) and of death (1.27; 95% CI, 1.09-1.47; p=.002). Adverse prognostic factors in a multivariate analysis of the outcomes of patients requiring IND2 included age, FLT3-ITD, adverse cytogenetics, and performance status. Pretransplant measurable residual disease retained a prognostic impact regardless of IND1 or IND2. Initial response to chemotherapy as determined by number of courses to attain CR, retained prognostic relevance even following SCT in CR.

Outcome of COVID-19 in patients with a history of acute leukemia; A Narrative Review

The chemotherapy and immunosuppressive medication may be associated with the suppressed immune system of a cancer patient making them susceptible to Coronavirus disease 2019 (COVID-19) with unclear mechanisms. We reviewed current studies on the clinical courses of leukemia patients with a risk of SARS-CoV-2 infection through searches in Pubmed databases and Google search engines. The criterion used for review includes their relevance to the defined review question, which is the outcome of COVID‐19 among leukemic patients and the relevant therapeutic interventions therewith. Patients with acute leukemia are among the most vulnerable groups of patients at risk of severe COVID-19 outcomes with several protocol management modifications proposed. The development of COVID-19 vaccines was an important milestone in reducing the risk of contracting and developing severe COVID-19 symptoms in leukemic patients after remission status. The European Society for Blood and Marrow Transplantation (EBMT), a collaborative network of centers and individuals working in the field of BMT and cellular therapy, has been updating its recommendations since the start of the COVID-19 pandemic.

Secondary plasma cell leukaemia (PCL) with plasmablastic morphology.

A 71-year-old female with relapsed IgA lambda myeloma developed progressive cytopenia. The peripheral blood film showed 5% blastoid cells. Flow cytometry analysis was indicative of plasma cells. The bone marrow smear was packed with plasmablasts. Target CD138-cell FISH and molecular karyotyping identified a complex genome. NGS identified high-risk mutations. Bone marrow histology confirmed myeloma with no evidence of acute leukaemia. The patient was diagnosed with plasmablastic progression of myeloma and secondary PCL. Secondary PCL patients have a poor prognosis. It is essential to recognize this subtype and explore a novel treatment approach.

Epidemiological characteristics and influencing factors of acute leukemia in children and adolescents and adults: a large population-based study

ABSTRACT Objective: To assess the epidemiological characteristics and prognostic factors of acute leukemia (AL) in children and adolescents, and make comparisons between pediatric and adult patients. Methods: This retrospective cohort study enrolled AL patients from the Surveillance, Epidemiology, and End Results (SEER) 1975–2016. OS in children and adolescents and adults with AL was compared and analyzed separately by age and AL subtype. Results: Totally 61,694 AL patients were identified, with 45,411 (73.6%) adults and 16,283 (26.4%) children and adolescents. From 2000 to 2016, the incidence rates of AL [annual percent changes (APC) = 1.2, 95%CI = 0.9–1.6, P < 0.05] and acute lymphoblastic leukemia (ALL) (APC = 1.5, 95%CI = 1.1–1.8, P < 0.05) in children and adolescents were significantly increasing. For adults, AL (APC = 0.9, 95%CI = 0.3–1.5, P < 0.05), ALL (APC = 2.5, 95%CI = 2.0–3.1, P < 0.05) and acute myeloid leukemia (AML) (APC = 0.9, 95%CI = 0.4–1.5, P < 0.05) had significantly elevated incidence rates. Overall survival (OS) in children and adolescents with AL was significantly higher than that in adults with AL (log-rank P < 0.0001). OS in children and adolescents and adults with ALL, AML and AUL decreased with age (all log-rank P < 0.0001). Older age, male sex and black race were risk factors for the survival of children and adolescents and adults with ALL, AML and AUL. Conclusion: From 2000 to 2016, the incidence rates of AL in children and adolescents and adults were increasing. Children and adolescents with AL had significantly better OS than adults with AL, and OS declined with age in both children and adolescents and adults with ALL, AML and AUL.