Measurable residual disease study through three different methods can anticipate relapse and guide pre-emptive therapy in childhood acute myeloid leukemia

Purpose Although outcomes of children with acute myeloid leukemia (AML) have improved over the last decades, around one-third of patients relapse. Measurable (or minimal) residual disease (MRD) monitoring may guide therapy adjustments or pre-emptive treatments before overt hematological relapse. Methods In this study, we review 297 bone marrow samples from 20 real-life pediatric AML patients using three MRD monitoring methods: multiparametric flow cytometry (MFC), fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR). Results Patients showed a 3-year overall survival of 73% and a 3-year event-free survival of 68%. Global relapse rate was of 25%. All relapses were preceded by the reappearance of MRD detection by: (1) MFC (p = 0.001), (2) PCR and/or FISH in patients with an identifiable chromosomal translocation (p = 0.03) and/or (3) one log increase of Wilms tumor gene 1 (WT1) expression in two consecutive samples (p = 0.02). The median times from MRD detection to relapse were 26, 111, and 140 days for MFC, specific PCR and FISH, and a one log increment of WT1, respectively. Conclusions MFC, FISH and PCR are complementary methods that can anticipate relapse of childhood AML by weeks to several months. However, in our series, pre-emptive therapies were not able to prevent disease progression. Therefore, more sensitive MRD monitoring methods that further anticipate relapse and more effective pre-emptive therapies are needed (AU)

Measurable residual disease study through three different methods can anticipate relapse and guide pre-emptive therapy in childhood acute myeloid leukemia.

PURPOSE: Although outcomes of children with acute myeloid leukemia (AML) have improved over the last decades, around one-third of patients relapse. Measurable (or minimal) residual disease (MRD) monitoring may guide therapy adjustments or pre-emptive treatments before overt hematological relapse. METHODS: In this study, we review 297 bone marrow samples from 20 real-life pediatric AML patients using three MRD monitoring methods: multiparametric flow cytometry (MFC), fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR). RESULTS: Patients showed a 3-year overall survival of 73% and a 3-year event-free survival of 68%. Global relapse rate was of 25%. All relapses were preceded by the reappearance of MRD detection by: (1) MFC (p = 0.001), (2) PCR and/or FISH in patients with an identifiable chromosomal translocation (p = 0.03) and/or (3) one log increase of Wilms tumor gene 1 (WT1) expression in two consecutive samples (p = 0.02). The median times from MRD detection to relapse were 26, 111, and 140 days for MFC, specific PCR and FISH, and a one log increment of WT1, respectively. CONCLUSIONS: MFC, FISH and PCR are complementary methods that can anticipate relapse of childhood AML by weeks to several months. However, in our series, pre-emptive therapies were not able to prevent disease progression. Therefore, more sensitive MRD monitoring methods that further anticipate relapse and more effective pre-emptive therapies are needed.

Relapsed Childhood Acute Myeloid Leukemia: Experience from a Single Tertiary Center in Thailand.

BACKGROUND: Few studies have examined survival outcomes in relapsed childhood acute myeloid leukemia (AML) in resource-limited countries. This study aimed to evaluate the prognostic factors and survival outcomes of relapsed childhood AML in Thailand. METHODS: The medical records of AML patients aged 0-15 years treated in a major tertiary center in Southern Thailand between December 1979 and December 2019 were reviewed retrospectively. The overall survival (OS) was calculated using the Kaplan-Meier method. RESULTS: A total of 316 AML patients were included and relapse occurred in 98 (31%) patients. Of these, 57 (58.2%) and 41 (41.8%) patients had early [≤1 year from first complete remission (CR1)] and late (>1 year from CR1) relapses, respectively. Only 54 (55.1%) patients received chemotherapy after relapse. The 3-year OS of all relapsed patients was 3.5%. The 3-year OS of patients with early and late relapse were 0% and 8.5%, respectively (p=0.002). The 3-year OS of patients who received chemotherapy and those who did not were 6.5% and 0%, respectively (p <0.0001). The median survival time of patients who did not receive chemotherapy was 1.7 months. The 3-year OS of patients who achieved second complete remission (CR2) and those who did not were 12.6% and 0%, respectively (p <0.001). CONCLUSION: The relapsed AML rate was 31% and the survival outcome was poor with a 3-year OS of 3.5%. The adverse prognostic factors were early relapse, failure to achieve CR2 and those who did not receive chemotherapy after relapse.

Bilateral Orbital Proptosis and Corneal Ulcer in a Child with Acute Myeloid Leukemia.

A 5-year-old girl had a 2-week history of protruding bilateral eye with blurred vision. The patient had a history of low-grade fever. Bilateral proptosis with a markedly severe protrusion of the conjunctival palpebral and infraorbital tissues was observed. A more pronounced proptosis occurred on the left eye. Lagophthalmos and corneal defects were found in the left eye. Laboratory tests revealed anemia, hyperleukocytosis, and thrombocytopenia. A confirmed diagnosis of acute myeloid leukemia-M2 was established from bone marrow aspiration. The patient was treated with standard multiagent chemotherapy and topical antibiotic eyedrops. Proptosis had resolved in 4 months with residual corneal cicatrix in the left eye.

Acute kidney injury and childhood acute myeloid leukemia.

BACKGROUND: Acute kidney injury (AKI) appears to be particularly common in children with acute myeloid leukemia (AML), although the epidemiology data on this patient population is sparse. The objective of this study was to assess the prevalence and factors associated with AKI in childhood AML during chemotherapy treatment. METHODS: The medical records of 112 children aged under 15 years diagnosed with AML who received chemotherapy in a major tertiary-care referral center in southern Thailand were reviewed. Logistic regression was used to identify factors associated with AKI. RESULTS: Fifty-six (50%) children had AKI events. The median time from AML diagnosis to the first AKI was 29.5 days (interquartile range: 11.0-92.8) and the median follow-up time was 10.9 months (interquartile range: 3.6-31.1). Age at diagnosis ≥ 10 years (OR 2.75, 95% CI 1.09-6.93), glomerular filtration rate < 90 mL/min/1.73 m2 at AML diagnosis (OR 7.58, 95% CI 1.89-30.5), and septic shock (OR 22.0, 95% CI 4.63-104.3) were independently associated with AKI. CONCLUSIONS: Childhood AML has a high rate of kidney injury with 50% having AKI. Age ≥ 10 years at diagnosis, impaired kidney function before treatment, and septic shock were strongly associated with AKI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Blood Count Recovery Following Induction Therapy for Acute Myeloid Leukemia in Children Does Not Predict Survival.

International Working Group (IWG) and European LeukemiaNet (ELN) response definitions are utilized to evaluate the efficacy of new agents for childhood acute myeloid leukemia (AML) for regulatory purposes. However, these criteria are not consistent with definitions used in pediatric AML trials or with standard pediatric practice to proceed with subsequent therapy cycles prior to IWG/ELN-defined count recovery. We retrospectively analyzed data from the two most recent Phase 3 pediatric AML clinical trials conducted by the Children's Oncology Group (COG) to assess the incidence, timing, and prognostic significance of count recovery following induction chemotherapy. Of the patients with fewer than 5% bone marrow blasts at the end of first induction, 21.5% of patients proceeded to a second induction cycle prior to achieving ANC ≥ 500 cells/µL and platelets ≥ 50,000 cells/µL, both well below the IWG/ELN thresholds of ANC > 1000 cells/µL and platelets > 100,000 cells/µL. In these two sequential childhood AML Phase 3 trials, neither ANC nor platelet recovery predicted survival. Intensification of treatment through the initiation of subsequent therapy cycles prior to attainment of IWG/ELN-defined CR is common practice in clinical trials for children with AML, suggesting that updated response definitions are needed for pediatric AML.

Impact of KMT2A Rearrangement and CSPG4 Expression in Pediatric Acute Myeloid Leukemia.

KMT2A rearrangements (KMT2A-r) are among the most common structural aberrations in pediatric acute myeloid leukemia (AML) and are very important for the risk group stratification of patients. Here, we report the outcome of 967 pediatric AML patients with a known KMT2A-r status. The large cohort was characterized by morphology, multicolor flow cytometry, classical cytogenetics and mutation analysis via panel sequencing. In total, the blasts of 241 patients (24.9%) showed KMT2A-r. KMT2A-r is associated with FAB M5, a high white blood cell count and younger age at diagnosis. When subgroups were combined, KMT2A-r had no impact on event-free survival (EFS) and overall survival (OS); however, various subgroups showed a different prognosis, ranging from a <50% OS for KMT2A/AFDN (n = 11) to a 100% chance of survival for patients harboring the rare translocation KMT2A/SEPTIN9 (n = 3, follow up of 3.7 to 9.6 years). A positive correlation of KMT2A-r with KRAS mutations (p < 0.001) existed, albeit without any prognostic impact. In addition, FLT3-ITDs were detected less frequently in AML with KMT2A-r (p < 0.001). Furthermore, KMT2A-r were mutually exclusive, with mutations in NPM1 (p = 0.002), KIT (p = 0.036), WT1 (p < 0.001) and CEBPA (p = 0.006), and translocations NUP98/NSD1 (p = 0.009), RUNX1/RUNX1T1 (p = 0.003) and CBFB/MYH11 (p = 0.006). In the 346 patients tested for CSPG4 expression, a correlation between CSPG4 expression and KMT2A-r was confirmed. However, CSPG4 expression also occurred in patients without KMT2A-r and had no significant prognostic impact on EFS and OS.

Survival Following Relapse in Children with Acute Myeloid Leukemia: A Report from AML-BFM and COG.

Post-relapse therapy remains critical for survival in children with acute myeloid leukemia (AML). We evaluated survival, response and prognostic variables following relapse in independent cooperative group studies conducted by COG and the population-based AML-BFM study group. BFM included 197 patients who relapsed after closure of the last I-BFM relapse trial until 2017, while COG included 852 patients who relapsed on the last Phase 3 trials (AAML0531, AAML1031). Overall survival at 5 years (OS) was 42 ± 4% (BFM) and 35 ± 2% (COG). Initial high-risk features (BFM 32 ± 6%, COG 26 ± 4%) and short time to relapse (BFM 29 ± 4%, COG 25 ± 2%) predicted diminished survival. In the BFM dataset, there was no difference in OS for patients who had a complete remission with full hematopoietic recovery (CR) following post-relapse re-induction compared to those with partial neutrophil and platelet recovery (CRp and CRi) only (52 ± 7% vs. 63 ± 10%, p = 0.39). Among 90 patients alive at last follow-up, 87 had received a post-relapse hematopoietic stem cell transplant (HSCT). OS for patients with post-relapse HSCT was 54 ± 4%. In conclusion, initial high-risk features and early relapse remain prognostic. Response assessment with full hematopoietic recovery following initial relapse therapy does not predict survival. These data indicate the need for post-relapse risk stratification in future studies of relapse therapies.

Second Relapse of Pediatric Patients with Acute Myeloid Leukemia: A Report on Current Treatment Strategies and Outcome of the AML-BFM Study Group.

Successful management of relapse is critical to improve outcomes of children with acute myeloid leukemia (AML). We evaluated response, survival and prognostic factors after a second relapse of AML. Among 1222 pediatric patients of the population-based AML-Berlin-Frankfurt-Munster (BFM) study group (2004 until 2017), 73 patients met the quality parameters for inclusion in this study. Central review of source documentation warranted the accuracy of reported data. Treatment approaches included palliation in 17 patients (23%), intensive therapy with curative intent (n = 46, 63%) and other regimens (n = 10). Twenty-five patients (35%) received hematopoietic stem cell transplantation (HSCT), 21 of whom (88%) had a prior HSCT. Survival was poor, with a five-year probability of overall survival (pOS) of 15 ± 4% and 31 ± 9% following HSCT (n = 25). Early second relapse (within one year after first relapse) was associated with dismal outcome (pOS 2 ± 2%, n = 44 vs. 33 ± 9%, n = 29; p < 0.0001). A third complete remission (CR) is required for survival: 31% (n = 14) of patients with intensive treatment achieved a third CR with a pOS of 36 ± 13%, while 28 patients (62%) were non-responders (pOS 7 ± 5%). In conclusion, survival is poor but possible, particularly after a late second relapse and an intensive chemotherapy followed by HSCT. This analysis provides a baseline for future treatment planning.

Dynamic Changes in the Ability to Release Neutrophil ExtraCellular Traps in the Course of Childhood Acute Leukemias.

Acute leukemias, the most common cancers in children, are characterized by excessive proliferation of malignant progenitor cells. As a consequence of impaired blood cell production, leukemia patients are susceptible to infectious complications-a major cause of non-relapse mortality. Neutrophil extracellular traps (NETs) are involved in various pathologies, from autoimmunity to cancer. Although aberrant NETs formation may be partially responsible for immune defects observed in acute leukemia, still little is known on the NET release in the course of leukemia. Here, we present the first comprehensive evaluation of NETs formation by neutrophils isolated from children with acute leukemia in different stages of the disease and treatment stimulated in vitro with phorbol 12-myristate 13-acetate (PMA), N-formyl-methionyl-leucyl-phenylalanine (fMLP), and calcium ionophore (CI). NETs release was measured using quantitative fluorescent method and visualized microscopically. In this setting, NETs release was significantly impaired in leukemic children both at the diagnosis and during the treatment, and full restoration of neutrophil function was achieved only after successful completion of the leukemia treatment. We suggest that neutrophil function impairment may result from both disease- and treatment-related factors. In this context, deficient innate immune response observed in acute leukemia patients may be present regardless of neutrophil count and contribute to secondary immunodeficiency observed in this population.

Allogeneic hematopoietic stem cell transplantation can improve the prognosis of high-risk pediatric t(8;21) acute myeloid leukemia in first remission based on MRD-guided treatment.

BACKGROUND: Pediatric acute myeloid leukemia (AML) with t(8;21) (q22;q22) is classified as a low-risk group. However, relapse is still the main factor affecting survival. We aimed to investigate the effect of allogeneic hematopoietic stem cell transplantation (allo-HSCT) on reducing recurrence and improving the survival of high-risk pediatric t(8;21) AML based on minimal residual disease (MRD)-guided treatment, and to further explore the prognostic factors to guide risk stratification treatment and identify who will benefit from allo-HSCT. METHODS: Overall, 129 newly diagnosed pediatric t(8;21) AML patients were included in this study. Patients were divided into high-risk and low-risk group according to RUNX1-RUNX1T1 transcript levels after 2 cycles of consolidation chemotherapy. High-risk patients were divided into HSCT group and chemotherapy group according to their treatment choices. The characteristics and outcomes of 125 patients were analyzed. RESULTS: For high-risk patients, allo-HSCT could improve 5-year relapse-free survival (RFS) rate compared to chemotherapy (87.4% vs. 61.9%; P = 0.026). Five-year overall survival (OS) rate in high-risk HSCT group had a trend for better than that in high-risk chemotherapy group (82.8% vs. 71.4%; P = 0.260). The 5-year RFS rate of patients with a c-KIT mutation in high-risk HSCT group had a trend for better than that of patients with a c-KIT mutation in high-risk chemotherapy group (82.9% vs. 75%; P = 0.400). Extramedullary infiltration (EI) at diagnosis was associated with a high cumulative incidence of relapse for high-risk patients (50% vs. 18.4%; P = 0.004); allo-HSCT can improve the RFS (P = 0.009). CONCLUSIONS: allo-HSCT can improve the prognosis of high-risk pediatric t(8;21) AML based on MRD-guided treatment. Patients with a c-KIT mutation may benefit from allo-HSCT. EI is an independent prognostic factor for high-risk patients and allo-HSCT can improve the prognosis.

Long-term outcome of childhood acute myeloid leukemia: A 10-year retrospective cohort study.

Acute Myeloid Leukemia (AML) in children is a serious disease. With a proper treatment, a long-term survival rate above 50% is typical. Before 2010, all the AML patients died in our hospital, and abandonment rate was more than 50%. The aims of this study are to explore the long-term outcome of newly childhood acute myeloid patients treated at Hue Central Hospital from 2010 to 2019.A retrospective study was conducted on 98 children with AML who admitted Hue Central Hospital from January 2010 to December 2019. The diagnosis was confirmed by morphological FAB criteria, cytochemistry and immunophenotype. Patients were treated with using modified AML 7-3 Regimen. Social supports were provided to patients/families. A total of 98 children with AML were analyzed with mean age of 5.6 years ranging from 3 months to 15 years. The male to female ratio was 1.8:1. The overall complete remission rate after induction were 82.6%). Patients accounted for 46 (46.9%) had relapses which occurred in during chemotherapy n=27 (27,6%), after finishing chemotherapy n=19(19,4%). Overall survival at 3 years were 23.2%. The event-free survival at 3 years were 20.2%o. Abandonment cases were 4 (4.1%). During the period study, abandonment has been reduced successfully with holistic strategies such as financial support, managing family group, providing education, early follow-up of patients who missed appointments and free accommodation near hospital for patients/families. However, with a high rate patient achieved complete remission after induction phase (82.6%), but the overal survival and event-free survival at 3 years were still low in my hospital (23.2 % and 20.2% respectively). It reflected that it was very difficult to treat successfully AML in lowand middle-income countries. We are considering the way how to improve the quality treatment for childhood acute myeloid leukemia in my hospital.

A six-gene-based prognostic model predicts complete remission and overall survival in childhood acute myeloid leukemia.

OBJECTIVE: Acute myeloid leukemia (AML) is a malignant clonal disorder. Despite enormous progress in its diagnosis and treatment, the mortality rate of AML remains high. The aim of this study was to identify prognostic biomarkers by using the gene expression profile dataset from public database, and to improve the risk-stratification criteria of survival for patients with AML. MATERIALS AND METHODS: The gene expression data and clinical parameter were acquired from the Therapeutically Applicable Research to Generate Effective Treatment (TARGET) database. A total of 856 differentially expressed genes (DEGs) were obtained from the childhood AML patients classified into first complete remission (CR1) group (n=791) and not CR group (n=249). We performed a series of bioinformatics analysis to screen key genes and pathways, further comprehending these DEGs through Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. RESULTS: Six genes (SLC17A7, MSX2, CDC26, MSLN, CTSZ and DEFA3) identified by univariate, Kaplan-Meier survival and multivariate Cox regression analyses were used to develop the prognostic model. Further analysis showed that the survival estimations in the high-risk group had an increased risk of death compared with the low-risk group based on the model. The area under the curve of the receiver operator characteristic curve in the prognostic model for predicting the overall survival was 0.729, confirming good prognostic model. We also performed a nomogram to provide an individual patient with the overall probability, and internal validation in the TARGET cohort. CONCLUSION: We identified a six-gene prognostic signature for risk-stratifying in patients with childhood AML. The risk classification model can be used to predict CR markers and may assist clinicians in providing realize the individualized treatment in this patient population.

Comprehensive analysis the potential biomarkers for the high-risk of childhood acute myeloid leukemia based on a competing endogenous RNA network.

Acute myeloid leukemia (AML) is a common form of hematological malignancies, the discovery of non-coding RNA (ncRNA) plays an important role in diverse biological processes including hematopoietic differentiation and proliferation. However, the interaction mechanism of key RNAs and their regulatory network in childhood AML are still to be elucidated. RNA profiles were downloaded from the Therapeutically Applicable Research to Generate Effective Treatment (TARGET) database and identified specific lncRNAs, miRNAs, and mRNAs in high-risk group of childhood AML. A lncRNA-mRNA-miRNA ceRNA network in childhood AML was constructed. A total of 2064 mRNAs, 615 lncRNAs, and 60 miRNAs were identified as significantly differentially expressed, and 13 lncRNAs, 7 miRNAs, and 67 mRNAs were incorporated in the ceRNA network. Functional analysis showed that these DEmRNAs were significantly enriched in Ras signaling pathway, TGF-beta signaling pathway, and other tumor-related pathways. Among the network, 10 RNAs (LINC00471, hsa-mir-100, hsa-mir-150, ANP32E, ERMP1, MYO1B, PAPD7, PTGIS, TERF1, and VEGFA) was associated with high-risk group of childhood AML and functions were significant for prognosis. Then, these findings together provide a new insight into the pathogenesis of high-risk group of childhood AML that can assist clinicians clarify the function of lncRNA to guide the treatment and in-depth study.

Construction of prognostic risk prediction model based on high-throughput sequencing expression profile data in childhood acute myeloid leukemia.

This study aimed to identify critical prognostic molecular markers in Childhood acute myeloid leukemia (AML) and construct nomogram-based model for prognostic prediction. The RNA-sequencing profiles and corresponding clinical information were downloaded from TCGA database. Differential expressed genes (DEG) were screened using limma package, subsequently following by GO and KEGG pathway analysis. Univariate and multivariate cox regression analysis were performed to screen critical DEGs. Nomogram-based prediction model were constructed to identify clinical factors with independent prognostic values, and the accuracy of this model was validated. A total of 214 DEGs were identified from relapse AML samples compared with non-relapse samples. These DEGs were mainly involved in twenty GO terms and three signaling pathways, such as chromatin assembly or disassembly, cytokine-cytokine receptor interaction, and JAK-STAT signaling pathway. Among these genes, Univariate and multivariate cox regression analysis results showed that relapse and risk score were significantly correlated with survival outcomes. Finally, the accuracy ability of nomogram-based prediction model was validated. These six DEGs (ABCA5, CYP7A1, HERC5, etc.) play major roles in AMLs progression. Our nomogram-based prognostic predictive model might be an effective method to estimate survival probability of AML patients with different risk status.

High incidence of acute kidney injury during chemotherapy for childhood acute myeloid leukemia.

BACKGROUND/OBJECTIVES: Childhood acute myeloid leukemia (AML) is a rare and heterogeneous disease. Pediatric data on the epidemiology of acute kidney injury (AKI) in AML are limited. We report on the incidence of AKI in childhood AML and the risk factors associated with AKI episodes. METHODS: A retrospective cohort of 53 patients (≤18 years), with de novo AML, receiving chemotherapy over a 10-year period. All serum creatinine (SCr) levels during therapy-related hospitalizations were assessed to stage AKI episodes as per Kidney Disease: Improving Global Outcomes criteria. Severe AKI was defined as AKI stages 2 or 3 and urine output criteria were not used. AKI risk factors were assessed independently in both cycle 1 alone and combining all chemotherapy cycles. RESULTS: AKI developed in 34 patients (64%) with multiple AKI episodes in 10 patients (46 total episodes). Twenty-four severe AKI episodes occurred in 23 patients (43.4%) with a mean duration of 26.1 days (SD 7.3). In cycle 1, hyperleukocytosis was not predictive of AKI, but severe sepsis was an independent risk factor of severe AKI (odds ratio [OR]: 13.4; 95% CI 1.9-94.9). With cycles combined, all subjects with AKI had severe sepsis and older age (≥10 years) was associated with severe AKI (OR: 20.8; 95% CI 3.8-112.2). CONCLUSION: There was a high incidence of AKI in our AML cohort with a strong association with older age (≥10 years) and severe sepsis. Larger prospective studies are needed to confirm the high burden of AKI and risk factors in this susceptible population.

Improved outcome of childhood acute myeloid leukemia in an Eastern European country: Lithuanian experience.

The reported treatment outcomes of children treated for cancer in Eastern European countries are inferior to those in Northern/Western Europe. We hypothesized that recent survival rates could be comparable to the current standards and performed a population-based analysis of treatment outcome of childhood acute myeloid leukemia (AML) in Lithuania, a small Eastern European country. Children < 18 years old who were treated for AML from 2000 to 2013 were included (n = 54). Estimates of 5-year event-free (EFS5y) and overall survival (OS5y) rates were analyzed. Comparing periods 2000-2006 (n = 32) and 2007-2013 (n = 22), the EFS5y improved from 31 to 63% (p = 0.04), and the OS5y improved from 31 to 72% (p = 0.02) because of reductions in toxicity-related mortality (42 vs. 15%, p = 0.08) and relapse (43 vs. 25%, p = 0.08). The most significant improvement was demonstrated in high-risk patients (OS5y improved from 26 to 75%, p = 0.02) who benefited from hematopoietic stem cell transplantation: the post-transplant EFS5y increased from 13 to 86% (p = 0.01). CONCLUSIONS: The current survival rate of Lithuanian children treated for AML was comparable to the expected rate in other parts of Europe. What is Known: • In the last three decades, significant improvement has been achieved in treating childhood cancer, with an overall survival (OS) rate of > 80% in high-income countries. The difference in survival rates between Northern/Western and Eastern European countries as well as between high- and middle-/low-income countries is as much as 20%. Recently, the 5-year event-free survival rate of acute myeloid leukemia (AML) has reached > 60% in high-income countries. The survival rates for myeloproliferative diseases were the lowest in Eastern European countries. • The reported inferior survival rates were calculated based on outcome data of patients treated until 2007. The recent survival rates in Eastern European countries are unknown. What is New: • Being a small Eastern European country, Lithuania has experienced good economic growth during the last decade. We hypothesized that economic growth and gain of experience could result in better survival rates of children treated for cancer in our country in recent years. • A population-based analysis of treatment outcome of childhood AML treated in Lithuania in the recent years was performed for the first time. The survival rates of childhood AML in Lithuania are comparable to those of other high-income countries. Current survival rates of children treated for cancer in Eastern European countries could be comparable to the best current standards contributing to better European survival rates of childhood cancer in general.

Decreased expression of microRNA-122 is associated with an unfavorable prognosis in childhood acute myeloid leukemia and function analysis indicates a therapeutic potential.

MicroRNA (miR)-122 functions as a tumor suppressor in various human cancers. However, its involvement in childhood acute myeloid leukemia (AML) remains unknown. In this study, quantitative real-time PCR assay demonstrated that miR-122 expression in bone marrow specimens from AML children were significantly lower than that in non-malignant controls (P<0.001). Statistically, AML children with low miR-122 expression more frequently had large white blood cell count (P=0.022), French-American-British classification subtype M7 (P<0.001), unfavorable cytogenetics (P=0.002) and day 7 response to the treatment (P=0.036), short relapse-free (P=0.001) and overall (P=0.008) survivals than those with high expression. Multivariate analysis also determined that miR-122 expression was an independent prognostic factor for both relapse-free and overall survivals. Functionally, the enforced expression of miR-122 in AML cell lines efficiently suppressed cell proliferation and reduced the ratio of S-phase cells in vitro (all P<0.05). In conclusion, the abnormal expression of miR-122 may be a marker of the aggressive progression in childhood AML. Importantly, its downregulation may serve as a prognostic factor to predict poor outcome. Our study also reveal that miR-122 may function as a tumor suppressor in childhood AML, highlighting a new therapeutic strategy for this malignancy.

Maternal fetal loss history and increased acute leukemia subtype risk in subsequent offspring: a systematic review and meta-analysis.

PURPOSE: History of fetal loss including miscarriage and stillbirth has been inconsistently associated with childhood (0-14 years) leukemia in subsequent offspring. A quantitative synthesis of the inconclusive literature by leukemia subtype was therefore conducted. METHODS: Eligible studies (N = 32) were identified through the screening of over 3500 publications. Random-effects meta-analyses were conducted on the association of miscarriage/stillbirth history with overall (AL; 18,868 cases/35,685 controls), acute lymphoblastic (ALL; 16,150 cases/38,655 controls), and myeloid (AML; 3042 cases/32,997 controls) leukemia. Sensitivity and subgroup analyses by age and ALL subtype, as well as meta-regression were undertaken. RESULTS: Fetal loss history was associated with increased AL risk [Odds Ratio (OR) 1.10, 95% Confidence Intervals (CI) 1.04-1.18]. The positive association was seen for ALL (OR 1.12, 95%CI 1.05-1.19) and for AML (OR 1.13, 95%CI 0.91-1.41); for the latter the OR increased in sensitivity analyses. Notably, stillbirth history was significantly linked to ALL risk (OR 1.33, 95%CI 1.02-1.74), but not AML. By contrast, the association of ALL and AML with previous miscarriage reached marginal significance. The association of miscarriage history was strongest in infant ALL (OR 2.34, 95%CI 1.19-4.60). CONCLUSIONS: In this meta-analysis involving >50,000 children, we found noteworthy associations by indices of fetal loss, age at diagnosis, and leukemia type; namely, of stillbirth with ALL and miscarriage history with infant ALL. Elucidation of plausible underlying mechanisms may provide insight into leukemia pathogenesis and indicate monitoring interventions prior to and during pregnancy.

Home remodeling and risk of childhood leukemia.

PURPOSE: We investigated the relationship between the risk of childhood leukemia and home remodeling, a surrogate for indoor chemical exposures. METHODS: We collected information on remodeling activities carried out between birth and diagnosis in homes of 609 acute lymphoblastic leukemia (ALL) cases, 89 acute myeloid leukemia (AML) cases, and 893 matched controls participating in the California Childhood Leukemia Study (1995-2008). We used multivariable logistic regression to estimate the risk of ALL and AML associated with six remodeling activities: construction, painting, recarpeting, reflooring, roofing, and weatherproofing. Models were adjusted for age, sex, Hispanic ethnicity, race, household annual income, and residential mobility. RESULTS: Construction in the home between birth and diagnosis was associated with a significant increase in ALL risk (odds ratio [OR]: 1.52, 95% confidence interval [CI]: 1.14-2.02) and a nonsignificant increase in AML risk (OR: 1.75, 95% CI: 0.98-3.15). No other remodeling activities were associated with ALL or AML risk in the main analysis. When stratifying by Hispanic ethnicity, a positive relationship between ALL risk and painting was evident in Hispanic children (OR: 1.47, 95% CI: 1.04-2.07). CONCLUSIONS: Specific home remodeling activities appeared to be associated with increased risk of childhood ALL.