Prognostic factors in high-grade pediatric osteosarcoma among children and young adults: Greek Nationwide Registry for Childhood Hematological Malignancies and Solid Tumors (NARECHEM-ST) data along with a systematic review and meta-analysis

The 5-year overall survival of children and adolescents with osteosarcoma has been in plateau during the last 30 years. The present systematic review (1976-2023) and meta-analysis aimed to explore factors implicated in the prognosis of children and young adults with high-grade osteosarcoma. Original studies including patients ≤30 years and the Nationwide Registry for Childhood Hematological Malignancies and Solid Tumors (NARECHEM-ST) data (2010-2021) referred to children ≤14 years were analysed. Individual participant data (IPD) and summary estimates were used to assess the n-year survival rates, as well as the association of risk factors with overall survival (OS) and event-free survival (EFS). IPD and the n-year survival rates were pooled using Kaplan-Meier and Cox regression models, and random effects models, respectively. Data from 8412 patients, including 46 publications, NARECHEM-ST data, and 277 IPD from 10 studies were analysed. The summary 5-year OS rate was 64% [95% confidence interval (95%CI): 62%-66%, 37 studies, 6661 patients] and the EFS was 52% (95%CI: 49%-56%, 30 studies, 5010 patients). The survival rates generally differed in the pre-specified subgroups. Limb-salvage surgery showed a higher 5-year OS rate (69%) versus amputation (47%). Good responders had higher OS rates at 3 years (94%) and 5 years (81%), compared to poor responders at 3 years (66%), and 5 years (56%). Patients with metastatic disease had a higher risk of death [Hazard Ratio (HR): 3.60, 95%CI: 2.52, 5.15, 11 studies]. Sex did not have an impact on EFS (HR females/males: 0.90, 95%CI: 0.54, 1.48, 3 studies), whereas age>18 years seems to adversely affect EFS (HR 18+/<10 years: 1.36, 95%CI: 1.09, 1.86, 3 studies). Our results summarize the collective experience on prognostic factors of high-grade osteosarcoma among children and young adults. Poor response to neoadjuvant chemotherapy and metastatic disease at diagnosis were confirmed as primary risk factors of poor outcome. International collaboration of osteosarcoma study groups is essential to improve survival.

Optimized Cytogenetic Risk-Group Stratification of KMT2A-Rearranged Pediatric Acute Myeloid Leukemia

Comprehensive international consensus on cytogenetic risk-group stratification of KMT2A-rearranged (KMT2A-r) pediatric acute myeloid leukemia (AML) is lacking. This retrospective (2005-2016) International Berlin-Frankfurt-Münster Study Group study on 1,256 children with KMT2A-r AML aimed to validate the prognostic value of established recurring KMT2A fusions and additional cytogenetic aberrations (ACAs), and secondly, to define additional, recurring KMT2A fusions and ACAs, evaluating their prognostic relevance. Compared to our previous study, three additional, recurring KMT2A-r groups were defined: Xq24/KMT2A::SEPT6, 1p32/KMT2A::EPS15, 17q12/t(11;17)(q23;q12). Across 13 KMT2A-r groups, 5-year event-free survival probabilities varied significantly (21.8% to 76.2%; P<0.01). ACAs occurred in 46.8% of 1,200 patients with complete karyotypes, correlating with inferior overall survival (56.8% vs 67.9%; P<0.01). Multivariable analyses confirmed independent associations of 4q21/KMT2A::AFF1, 6q27/KMT2A::AFDN, 10p12/KMT2A::MLLT10, 10p11.2/KMT2A::ABI1, and 19p13.3/KMT2A::MLLT1 with adverse outcomes, but not those of 1q21/KMT2A::MLLT11 and trisomy 19 with favorable and adverse outcomes, respectively. Newly identified ACAs with independent adverse prognoses were monosomy 10, trisomies 1, 6, 16, and X, add(12p), and del(9q). Among patients with 9p22/KMT2A::MLLT3, the independent association of French-American-British-type M5 with favorable outcome was confirmed, and those of trisomy 6 and measurable residual disease at end of induction with adverse outcomes were identified. We provide evidence to incorporate the five adverse-risk KMT2A fusions into the cytogenetic risk-group stratification of KMT2A-r pediatric AML, to revise the favorable-risk classification of 1q21/KMT2A::MLLT11 to intermediate risk, and to refine risk-stratification of 9p22/KMT2A::MLLT3 AML. Future studies should validate the associations between the newly identified ACAs and outcome, and unravel the underlying biological pathogenesis of KMT2A fusions and ACAs.

Loss-of-phosphorylation of IKZF1 results in gain-of-function associated with immune dysregulation

BACKGROUND

Immune dysregulation often presents as autoimmunity, inflammation, and/or lymphoproliferation. Several germline genetic defects have been associated with immune dysregulation; they include heterozygous gain-of-function (GOF) mutations in IKZF1, an essential transcription factor for hematopoiesis containing zinc finger domains (ZFs). However, in a large percentage of patients, the genetic origin of their immunedysregulation remains undetermined.

OBJECTIVE

A family with 2 members presenting immune dysregulation signs was studied to identify the genetic cause of their disease.

METHODS

Whole exome sequencing, analysis of immunologic parameters, and functional assays (including Western blotting, electrophoretic mobility shift assay during the cell cycle, and TH cell differentiation) were performed.

RESULTS

The 2 patients carried a novel heterozygous mutation in IKZF1 (IKZF1T398M). IKZF1 heterozygous mutations have previously been shown to be responsible for several distinct human immunologic diseases by directly affecting the ability of ZFs to bind to DNA or to dimerize. Herein, we showed that the IKZF1T398M, which is outside the ZFs, caused impaired phosphorylation of IKZF1, resulting in enhanced DNA-binding ability at the S phase of the cell cycle, reduction of the G1-S phase transition, and decreased proliferation. Confirming these data, similar functional alterations were observed with IKZF1T398A, but not with IKZF1T398D, mimicking dephosphorylation and phosphorylation, respectively. In T lymphocytes, expression of IKZF1T398M led to TH cell differentiation skewed toward TH2 cells. Thus, our data indicate that IKZF1T398M behaves as a GOF variant underlying immune dysregulation.

CONCLUSION

Disturbed IKZF1 phosphorylation represents a novel GOF mechanism (GOF by loss of phosphorylation (termed as GOF-LOP) associated with immune dysregulation, highlighting the regulatory role of IKZF1 during cell cycle progression through phosphorylation.

Spontaneous remission and loss of monosomy 7: a window of opportunity for young children with SAMD9L syndrome

Monosomy 7 is the most common cytogenetic abnormality in pediatric myelodysplastic syndrome (MDS) and associated with a high risk of disease progression. However, in young children, spontaneous loss of monosomy 7 with concomitant hematologic recovery has been described, especially in the presence of germline mutations in SAMD9 and SAMD9L genes. Here, we report on our experience of close surveillance instead of upfront hematopoietic stem cell transplantation (HSCT) in seven patients diagnosed with SAMD9L syndrome and monosomy 7 at a median age of 0.6 years (range, 0.4-2.9). Within 14 months from diagnosis, three children experienced spontaneous hematological remission accompanied by a decrease in monosomy 7 clone size. Subclones with somatic SAMD9L mutations in cis were identified in five patients, three of whom attained hematological remission. Two patients acquired RUNX1 and EZH2 mutations during the observation period, of whom one progressed to myelodysplastic syndrome with excess of blasts (MDS-EB). Four patients underwent allogeneic HSCT at a median time of 26 months (range, 14-40) from diagnosis for MDSEB, necrotizing granulomatous lymphadenitis, persistent monosomy 7, and severe neutropenia. At last follow-up, six patients were alive, while one passed away due to transplant-related causes. These data confirm previous observations that monosomy 7 can be transient in young children with SAMD9L syndrome. However, they also indicate that delaying HSCT poses a substantial risk of severe infection and disease progression. Finally, surveillance of patients with SAMD9L syndrome and monosomy 7 is critical to define the evolving genetic landscape and to determine the appropriate timing of HSCT (clinicaltrials gov. Identifier: NCT00662090).

The inter-familiar issues of Greek parents facing childhood cancer

Cancer as a whole, but especially childhood cancer, creates a number of psychological, social, and family problems as well as practical and financial issues, which every parent is called upon to solve. This study focuses on childhood cancer and aims at a thorough analysis of the physical/organic, psychological, and social problems associated with the parents and relatives of a child with cancer. The special element in pediatric neoplasms is not only the vulnerable population target group, but also the set of secondary effects it has on the environment of the sick child. The research was conducted on a sample of 133 families of children with cancer, and the results were displayed after statistical processing and data analysis with R statistical software. The results of the study confirm with statistically significant data the effect of childhood cancer on the physical, mental, and social health and behavior of the parent. Thus, 53.8% of the respondents stated 5 and above on the 7-point Likert scale for fatigue issues, 55.6% for sleep disorders, 78.1% for stress, and 82.7% for fear. The key findings are characterized by high specificity as it is a unique study that reveals particular aspects of the Greek parent's behavior, mind, and body during the period of their child's illness.   Conclusion: The effects of childhood illnesses, particularly when they are severe, such as neoplasms, present a looming threat, ushering in a multitude of adverse alterations in the daily lives of the affected child's family. What is Known - What is New: • We know the effects that a childhood illness brings not only to the sick child, but also to the entire family circle. The new element in the present research is that these data reflect the situation in Greece, for which the research data in this area is quite limited. Our research is one of the few studies that demonstrate with statistical data the change in the psychosomatic health of the parent who has a child with cancer.

The role of 18F-FDG PET/CT imaging in paediatric Langerhans disease: Case report

Langerhans cell histiocytosis (LCH) is a haematological disorder, affecting single or multiple organs, characterized by abnormal proliferation of Langerhans cells in children. Accurate tumour delineation (number of lesions, organs involved) is crucial for staging/re-staging, and follow-up (response to therapy). Conventional imaging techniques (computed tomography (CT), magnetic resonance imaging (MRI)) have been employed for initial diagnosis, staging and assessment of response to therapy focusing on the healing effect therapeutic protocols have on the disease. In this case report, whole-body positron emission tomography/computed tomography (PET/CT) was shown either to provide information on the metabolic activity of histiocytes, or identify lesions otherwise asymptomatic. It is clear that PET/CT, combining anatomic and metabolic information, provides data for accurate staging, therapeutic protocol selection and assessment of response to therapy.

Measurable Residual Disease and Fusion Partner Independently Predict Survival and Relapse Risk in Childhood KMT2A-Rearranged Acute Myeloid Leukemia: A Study by the International Berlin-Frankfurt-Münster Study Group

PURPOSE

A previous study by the International Berlin-Frankfurt-Münster Study Group (I-BFM-SG) on childhood KMT2A-rearranged (KMT2A-r) AML demonstrated the prognostic value of the fusion partner. This I-BFM-SG study investigated the value of flow cytometry-based measurable residual disease (flow-MRD) and evaluated the benefit of allogeneic stem-cell transplantation (allo-SCT) in first complete remission (CR1) in this disease.

METHODS

A total of 1,130 children with KMT2A-r AML, diagnosed between January 2005 and December 2016, were assigned to high-risk (n = 402; 35.6%) or non-high-risk (n = 728; 64.4%) fusion partner-based groups. Flow-MRD levels at both end of induction 1 (EOI1) and 2 (EOI2) were available for 456 patients and were considered negative (<0.1%) or positive (≥0.1%). End points were 5-year event-free survival (EFS), cumulative incidence of relapse (CIR), and overall survival (OS).

RESULTS

The high-risk group had inferior EFS (30.3% high risk v 54.0% non-high risk; P < .0001), CIR (59.7% v 35.2%; P < .0001), and OS (49.2% v 70.5%; P < .0001). EOI2 MRD negativity was associated with superior EFS (n = 413; 47.6% MRD negativity v n = 43; 16.3% MRD positivity; P < .0001) and OS (n = 413; 66.0% v n = 43; 27.9%; P < .0001), and showed a trend toward lower CIR (n = 392; 46.1% v n = 26; 65.4%; P = .016). Similar results were obtained for patients with EOI2 MRD negativity within both risk groups, except that within the non-high-risk group, CIR was comparable with that of patients with EOI2 MRD positivity. Allo-SCT in CR1 only reduced CIR (hazard ratio, 0.5 [95% CI, 0.4 to 0.8]; P = .00096) within the high-risk group but did not improve OS. In multivariable analyses, EOI2 MRD positivity and high-risk group were independently associated with inferior EFS, CIR, and OS.

CONCLUSION

EOI2 flow-MRD is an independent prognostic factor and should be included as risk stratification factor in childhood KMT2A-r AML. Treatment approaches other than allo-SCT in CR1 are needed to improve prognosis.

Prognostic Factors for Cardiotoxicity among Children with Cancer: Definition, Causes, and Diagnosis with Omics Technologies

Improvements in the treatment of childhood cancer have considerably enhanced survival rates over the last decades to over 80% as of today. However, this great achievement has been accompanied by the occurrence of several early and long-term treatment-related complications major of which is cardiotoxicity. This article reviews the contemporary definition of cardiotoxicity, older and newer chemotherapeutic agents that are mainly involved in cardiotoxicity, routine process diagnoses, and methods using omics technology for early and preventive diagnosis. Chemotherapeutic agents and radiation therapies have been implicated as a cause of cardiotoxicity. In response, the area of cardio-oncology has developed into a crucial element of oncologic patient care, committed to the early diagnosis and treatment of adverse cardiac events. However, routine diagnosis and the monitoring of cardiotoxicity rely on electrocardiography and echocardiography. For the early detection of cardiotoxicity, in recent years, major studies have been conducted using biomarkers such as troponin, N-terminal pro b-natriuretic peptide, etc. Despite the refinements in diagnostics, severe limitations still exist due to the increase in the above-mentioned biomarkers only after significant cardiac damage has occurred. Lately, the research has expanded by introducing new technologies and finding new markers using the omics approach. These new markers could be used not only for early detection but also for the early prevention of cardiotoxicity. Omics science, which includes genomics, transcriptomics, proteomics, and metabolomics, offers new opportunities for biomarker discovery in cardiotoxicity and may provide an understanding of the mechanisms of cardiotoxicity beyond traditional technologies.

The Prognostic Effect of CDKN2A/2B Gene Deletions in Pediatric Acute Lymphoblastic Leukemia (ALL): Independent Prognostic Significance in BFM-Based Protocols

One of the most frequent genes affected in pediatric ALL is the CDKN2A/2B gene, acting as a secondary cooperating event and playing an important role in cell-cycle regulation and chemosensitivity. Despite its inclusion in combined CNA (copy-number alterations) classifiers, like the IKZF1plus entity and the UKALL CNA profile, the prognostic impact of the individual gene deletions outside the context of a combined CNA evaluation remains controversial. Addressing the CDKN2A/2B deletions' additive prognostic effect in current risk-stratification algorithms, we present a retrospective study of a Greek pediatric ALL cohort comprising 247 patients studied over a 24-year period (2000-2023). Herein, we provide insight regarding the correlation with disease features, MRD clearance, and independent prognostic significance for this ALL cohort treated with contemporary BFM-based treatment protocols. Within an extended follow-up time of 135 months, the presence of the CDKN2A/2B deletions (biallelic or monoallelic) was associated with inferior EFS rates (65.1% compared to 91.8% for the gene non-deleted subgroup, p < 0.001), with the relapse rate accounting for 22.2% and 5.9%, respectively (p < 0.001). The presence of the biallelic deletion was associated with the worst outcomes (EFS 57.2% vs. 89.6% in the case of any other status, monoallelic or non-deleted, p < 0.001). Survival differences were demonstrated for B-ALL cases (EFS 65.3% vs. 93.6% for the non-deleted B-ALL subgroup, p < 0.001), but the prognostic effect was not statistically significant within the T-ALL cohort (EFS 64.3 vs. 69.2, p = 0.947). The presence of the CDKN2A/2B deletions clearly correlated with inferior outcomes within all protocol-defined risk groups (standard risk (SR): EFS 66.7% vs. 100%, p < 0.001, intermediate risk (IR): EFS 77.1% vs. 97.9%, p < 0.001, high risk (HR): EFS 42.1% vs. 70.5% p < 0.001 for deleted vs non-deleted cases in each patient risk group); additionally, in this study, the presence of the deletion differentiated prognosis within both MRD-positive and -negative subgroups on days 15 and 33 of induction. In multivariate analysis, the presence of the CDKN2A/2B deletions was the most important prognostic factor for relapse and overall survival, yielding a hazard ratio of 5.2 (95% confidence interval: 2.59-10.41, p < 0.001) and 5.96 (95% confidence interval: 2.97-11.95, p < 0.001), respectively, designating the alteration's independent prognostic significance in the context of modern risk stratification. The results of our study demonstrate that the presence of the CDKN2A/2B deletions can further stratify all existing risk groups, identifying patient subgroups with different outcomes. The above biallelic deletions could be incorporated into future risk-stratification algorithms, refining MRD-based stratification. In the era of targeted therapies, future prospective controlled clinical trials will further explore the possible use of cyclin-dependent kinase inhibitors (CDKIs) in CDKN2A/2B-affected ALL pediatric subgroups.

Adolescents and young adults (AYA) with acute myeloid leukemia (AML): real-world long-term results and age-specific outcomes

Opposing acute lymphoblastic leukemia, sparse data about AYAs with acute myeloid leukemia (AML) is available. Overall, 125 AYAs (age 10-35 years) treated during the last two decades were evaluated and compared to 385 older patients. CBF leukemia was more frequent in AYAs (21.6% vs. 8%, p < 0.001); however, many presented high-risk features. AYAs showed improved complete remission rate (CR, 80% vs. 65%, p = 0.01), lower cumulative incidence of relapse and TRM and longer survival (5 year-OS 53% vs. 24%, p < 0.0001), observed mainly in intermediate-risk karyotype. Adolescents displayed even better outcomes (5 year-OS 69%). AlloHCT in CR1 was beneficial for nonadolescent AYAs (5 year-OS 66.7% vs. 44.4% without HCT, p = 0.04). Among 50 APL patients, 19 AYAs experienced better outcomes than older, mainly attributed to reduced treatment-related mortality (TRM, 5% vs. 19%, p = 0.1). We observed an important (>10%) survival gain for AYAs during the last decade. However, AYAs have still unmet needs to obtain optimal cure rates.

Analysis of rare driving events in pediatric acute myeloid leukemia

Elucidating genetic aberrations in pediatric acute myeloid leukemia (AML) provides insight in biology and may impact on risk-group stratification and clinical outcome. This study aimed to detect such aberrations in a selected series of samples without known (cyto)genetic aberration using molecular profiling. A cohort of 161 patients was selected from various study groups: DCOG, BFM, SJCRH, NOPHO and AEIOP. Samples were analyzed using RNA sequencing (n=152), whole exome (n=135) and/or whole genome sequencing (n=100). In 70 of 156 patients (45%), of whom RNA sequencing or whole genome sequencing was available, rearrangements were detected, 22 of which were novel; five involving ERG rearrangements and four NPM1 rearrangements. ERG rearrangements showed self-renewal capacity in vitro, and a distinct gene expression pattern. Gene set enrichment analysis of this cluster showed upregulation of gene sets derived from Ewing sarcoma, which was confirmed comparing gene expression profiles of AML and Ewing sarcoma. Furthermore, NPM1-rearranged cases showed cytoplasmic NPM1 localization and revealed HOXA/B gene overexpression, as described for NPM1 mutated cases. Single-gene mutations as identified in adult AML were rare. Patients had a median of 24 coding mutations (range, 7-159). Novel recurrent mutations were detected in UBTF (n=10), a regulator of RNA transcription. In 75% of patients an aberration with a prognostic impact could be detected. Therefore, we suggest these techniques need to become standard of care in diagnostics.

A national study of antibiotic use in Greek pediatric hematology oncology and bone marrow transplant units

OBJECTIVE

We surveyed antimicrobials used in Greek pediatric hematology-oncology (PHO) and bone marrow transplant (BMT) units before and after an intervention involving education regarding the 2017 clinical practice guidelines (CPG) for the management of febrile neutropenia in children with cancer and hematopoietic stem-cell transplant recipients.

DESIGN

Antibiotic prescribing practices were prospectively recorded between June 2016 and November 2017.

INTERVENTION

In December 2017, baseline data feedback was provided, and CPG education was provided. Prescribing practices were followed for one more year. For antibiotic stewardship, days of therapy, and length of therapy were calculated.

SETTING

Five of the 6 PHO units in Greece and the single pediatric BMT unit participated.

PARTICIPANTS

Admitted children in each unit who received the first 15 new antibiotic courses each month.

RESULTS

Administration of ≥4 antibiotics simultaneously and administration of antibiotics with overlapping activity for ≥2 days were significantly more common in PHO units in general hospitals compared to children's hospitals. Use of at least 1 antifungal was recorded in ∼47% of the patients before and after the intervention. De-escalation and/or discontinuation of antibiotics on day 6 of initial treatment increased significantly from 43% to 53.5% (P = .032). Although the number of patients requiring intensive care support for sepsis did not change, a significant drop was noted in all-cause mortality (P = .008).

CONCLUSIONS

We recorded the antibiotic prescribing practices in Greek PHO and BMT units, we achieved improved prescribing with a simple intervention, and we identified areas in need of improvement.

Integrative Genomic Analysis of Pediatric Myeloid-Related Acute Leukemias Identifies Novel Subtypes and Prognostic Indicators

Integrating somatic mutation analysis and gene expression profiling distinguishes pediatric AML subtypes with differential prognoses and clinical risks.

Genomic characterization of pediatric patients with acute myeloid leukemia (AML) has led to the discovery of somatic mutations with prognostic implications. Although gene-expression profiling can differentiate subsets of pediatric AML, its clinical utility in risk stratification remains limited. Here, we evaluate gene expression, pathogenic somatic mutations, and outcome in a cohort of 435 pediatric patients with a spectrum of pediatric myeloid-related acute leukemias for biological subtype discovery. This analysis revealed 63 patients with varying immunophenotypes that span a T-lineage and myeloid continuum designated as acute myeloid/T-lymphoblastic leukemia (AMTL). Within AMTL, two patient subgroups distinguished by FLT3-ITD and PRC2 mutations have different outcomes, demonstrating the impact of mutational composition on survival. Across the cohort, variability in outcomes of patients within isomutational subsets is influenced by transcriptional identity and the presence of a stem cell–like gene-expression signature. Integration of gene expression and somatic mutations leads to improved risk stratification.

Fish evaluation of additional cytogenetic aberrations and hyperdiploidy in childhood Burkitt lymphoma

Beyond MYC rearrangement, Burkitt lymphoma (BL) often presents with additional aberrations. Biopsy touch imprints from 72 children with BL were tested with interphase fluorescence in-situ hybridization (i-FISH) for MYC, BCL2, BCL6, IGH, IGK and IGL rearrangements and copy-number aberrations involving 1q21/1p32, 7cen/7q31, 9cen/9p21, 13q14/13q34 and 17cen/17p13. Diploid status deviations were investigated with chromosome enumeration probes. MYC rearrangement was demonstrated in all cases. Additional aberrations included +1q (21/72:29.2%), +7q (14/72:19.4%), 13q- (14/72:19.4%), 9p-(6/72:8.3%) and hyperdiploidy (6/72:8.3%). Advanced clinical stage IV, +7q and 9p- were associated with shorter overall survival, with stage IV and +7q retaining prognostic significance on multivariate analysis. No relapse or death was reported among the hyperdiploid cases. This i-FISH investigation provides information on the genetic profile of BL and may prove valuable for patients with no karyotype analysis. Demonstration of hyperdiploidy could evolve research on clonal evolution pathways and probably identify a subgroup of children with favorable prognosis.

Clinical evolution, genetic landscape and trajectories of clonal hematopoiesis in SAMD9/SAMD9L syndromes

Germline SAMD9 and SAMD9L mutations (SAMD9/9L^mut) predispose to myelodysplastic syndromes (MDS) with propensity for somatic rescue. In this study, we investigated a clinically annotated pediatric MDS cohort (n = 669) to define the prevalence, genetic landscape, phenotype, therapy outcome and clonal architecture of SAMD9/9L syndromes. In consecutively diagnosed MDS, germline SAMD9/9L^mut accounted for 8% and were mutually exclusive with GATA2 mutations present in 7% of the cohort. Among SAMD9/9L^mut cases, refractory cytopenia was the most prevalent MDS subtype (90%); acquired monosomy 7 was present in 38%; constitutional abnormalities were noted in 57%; and immune dysfunction was present in 28%. The clinical outcome was independent of germline mutations. In total, 67 patients had 58 distinct germline SAMD9/9L^mut clustering to protein middle regions. Despite inconclusive in silico prediction, 94% of SAMD9/9L^mut suppressed HEK293 cell growth, and mutations expressed in CD34⁺ cells induced overt cell death. Furthermore, we found that 61% of SAMD9/9L^mut patients underwent somatic genetic rescue (SGR) resulting in clonal hematopoiesis, of which 95% was maladaptive (monosomy 7 ± cancer mutations), and 51% had adaptive nature (revertant UPD7q, somatic SAMD9/9L^mut). Finally, bone marrow single-cell DNA sequencing revealed multiple competing SGR events in individual patients. Our findings demonstrate that SGR is common in SAMD9/9L^mut MDS and exemplify the exceptional plasticity of hematopoiesis in children.

Copy Number Alteration Profile Provides Additional Prognostic Value for Acute Lymphoblastic Leukemia Patients Treated on BFM Protocols

Simple Summary

Recent advances in genomic analyses of acute lymphoblastic leukemia (ALL) have identified novel prognostic markers associated with patient outcome. In this frame, copy number alterations (CNAs) are constantly gaining relevance as potential risk stratification markers. Herein, we present our data of a proposed CNA-profile risk-index applied on a Greek ALLIC-BFM cohort. The results of our study demonstrate that EFS for GR(good-risk)-CNA-profile patients was 96.0% versus 57.6% of PR(poor-risk)-CNA-profile ones (p < 0.001) in the whole cohort. EFS within the IR-group for the GR-CNA vs. PR-CNA subgroups was 100.0% vs. 60.0% (p < 0.001), and within the HR-group, 88.2% vs. 55.6% (p = 0.047), respectively. The above results indicate that the application of the proposed CNA-profile classifier is feasible in BFM-based protocols, adding prognostic value to the existing prognostic markers and successfully stratifying patients within prognostic subgroups. This novel genomic risk index can be incorporated in future risk-stratification algorithms, further refining MRD-based stratification and possibly reassigning optimal treatment strategies.

Abstract

We present our data of a novel proposed CNA-profile risk-index, applied on a Greek ALLIC-BFM-treated cohort, aiming at further refining genomic risk-stratification. Eighty-five of 227 consecutively treated ALL patients were analyzed for the copy-number-status of eight genes (IKZF1/CDKN2A/2B/PAR1/BTG1/EBF1/PAX5/ETV6/RB1). Using the MLPA-assay, patients were stratified as: (1) Good-risk(GR)-CNA-profile (n = 51), with no deletion of IKZF1/CDKN2A/B/PAR1/BTG1/EBF1/PAX5/ETV6/RB1 or isolated deletions of ETV6/PAX5/BTG1 or ETV6 deletions with a single additional deletion of BTG1/PAX5/CDKN2A/B. (2) Poor-risk(PR)-CNA-profile (n = 34), with any deletion of ΙΚΖF1/PAR1/EBF1/RB1 or any other CNA. With a median follow-up time of 49.9 months, EFS for GR-CNA-profile and PR-CNA-profile patients was 96.0% vs. 57.6% (p < 0.001). For IR-group and HR-group patients, EFS for the GR-CNA/PR-CNA subgroups was 100.0% vs. 60.0% (p < 0.001) and 88.2% vs. 55.6% (p = 0.047), respectively. Among FC-MRD_d15 + patients (MRD_d15 ≥ 10⁻⁴), EFS rates were 95.3% vs. 51.7% for GR-CNA/PR-CNA subjects (p < 0.001). Similarly, among FC-MRD_d33 + patients (MRD_d33 ≥ 10⁻⁴), EFS was 92.9% vs. 27.3% (p < 0.001) and for patients FC-MRD_d33 − (MRD_d33 < 10⁻⁴), EFS was 97.2% vs. 72.7% (p = 0.004), for GR-CNA/PR-CNA patients, respectively. In a multivariate analysis, the CNA-profile was the most important outcome predictor. In conclusion, the CNA-profile can establish a new genomic risk-index, identifying a distinct subgroup with increased relapse risk among the IR-group, as well as a subgroup of patients with superior prognosis among HR-patients. The CNA-profile is feasible in BFM-based protocols, further refining MRD-based risk-stratification.

The paradigm of hematological malignant versus non-malignant manifestations, driven by primary immunodeficiencies: a complex interplay

Hematological malignancies (HM) developed on underlying primary immunodeficiencies (PID) are rare and of unusual features. Differentiating between malignant and non-malignant lymphoproliferation in cases of pediatric hematology and oncology and revealing their molecular predisposition demonstrate the complex interplay between PID and HM. We retrospectively studied a case series of seven pediatric patients, all with PID with manifestations raising suspicion for HM or hypereosinophilic syndrome (HES) or confirmed HM of lymphoid origin. Combined immunodeficiency (CID) without detection of a known mutated gene or with ataxia-telangiectasia (AT), STAT3 gain of function (GOF), DOCK8 deficiency, and CTLA4 deficiency were diagnosed in three, one, one, one, and one patient, respectively. Acute lymphoblastic leukemia and Hodgkin lymphoma followed by second primary Burkitt lymphoma were diagnosed in one patient with CID each, while lymphomatoid granulomatosis in one patient with AT. Lymphoproliferative disease occurred in STAT3 GOF, CTLA4 deficiency and CID, one patient each, and idiopathic HES in DOCK8 deficiency (median age at presentation of PID or any hematological manifestation: four years). Four patients underwent hematopoietic cell transplantation (HCT) for STAT3 GOF, DOCK8 deficiency and CID in one, one, and two cases, respectively (median age: 10 years). At the last follow-up, all transplanted patients were alive. Reporting on patients' phenotype, genotype and course of disease shed light on the prevalence, characteristics, and pathophysiology of HM complicating PID. Discriminating the non-yet malignant lymphoproliferation from its malignant equivalent on the same pathophysiology background proved of additional value. Outcomes of PID after HCT, herein reported, are favorable.

Overall and event-free survival of childhood lymphoma in Greece: analysis of harmonized clinical data over a 24-year active registration period

We assessed event-free (EFS) and overall (OS) survival in 676 incident cases of childhood Hodgkin (HL) and non-Hodgkin (NHL) lymphoma actively registered in Greece (1996-2019). HL-OS_5-year was 96% and NHL-OS_5-year 85%, whereas HL-EFS_5-year was 86% and NHL-EFS_5-year was 81%, notably similar to the respective OS rates (HL: 95%, NHL: 85%) in developed countries. For HL, older age at diagnosis, high maternal education and close proximity to treatment centers were linked to remarkably favorable outcomes. By contrast, stage IV patients showed worse OS and EFS. HL patients with low levels of hemoglobin were associated with worse EFS (hazard ratio: 2.81, 95% confidence intervals: 1.09-7.22). OS (76%) and EFS (73%) were poor among high-risk NHL patients and those with increased LDH (71%). The identified predictors of poor disease outcome point to the need for intensification of individualized treatments. Ongoing clinical cancer registration entailing clinical components could contribute to use of state-of-the-art treatments.

Long-term outcome, clinical course and treatment approaches of paediatric langerhans cell histiocytosis: A greek reference centre report

AIM

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia with diverse clinical behaviour. In this article, we studied the clinical course, management and long-term outcomes of a paediatric cohort treated by our reference centre.

METHODS

We retrospectively studied 66 children with LCH, consecutively diagnosed by a Greek reference centre from 1974 to 2020.

RESULTS

The patients had a median age of 3.9 (range 0.0-15.9) years, 39 and 6 patients were diagnosed with unifocal or multifocal single system disease and 14 and 7 had multisystem disease with or without risk organ involvement. No late occurrence of clinical neurodegenerative disease or diabetes insipidus were observed at a median follow-up period of 4.1 (range 0.5-27.7) years. The 10-year event-free survival and overall survival were 65.0% and 90.3% and improved significantly over a 45-year period. Survival was superior in single system than multisystem cases. BRAF V600E mutation was found in 8/14 tested patients. Reactivation occurred in 12/66 patients (18.2%); 11 achieved remission and one patient died after a second relapse.

CONCLUSION

LCH survival rates significantly increased in our cohort over time. Reactivation occurred in 18.2% patients, but no late neurodegeneration was found. The prognostic value of single system disease status vs. multisystem LCH was confirmed.

Severe aplastic anaemia in children: Impact of histopathology profile and treatment on very long-term outcomes

AIM

To assess very long-term outcomes of children with severe aplastic anaemia (SAA) and impact of histopathology and of different treatments over time.

METHODS

We conducted a retrospective study of 57 consecutive patients with SAA during 1973-2019. According to period, treatment consisted of androgens, immunosuppressive treatment (IST) and haematopoietic cell transplantation (HCT) in 14, 31 and 13 patients, respectively. Histopathology immune profiles were studied on bone marrow (BM).

RESULTS

Response rate (RR) to androgens was 35%, with long-term survivorship in 4 of 5 responders. RR and 10-year overall survival (OS) after IST was 65% and 80%, respectively. RR was higher in girls (92% vs 43% in boys, P = .02). Mean baseline BM values of CD34 + and of B-lymphocytes in responders vs non-responders were 1.3% vs 0 (P = .08) and 14.1% vs 9.7% (P = .07), respectively. After IST, BM cellularity gradually increased and cytotoxic T-lymphocytes decreased (time variation P = .003 and 0.07, respectively). Outcome did not differ between patients with IST or frontline HCT. Ten-year OS improved over time, increasing from 35.3% to 77.1% and 77% during 1973-1985, 1986-2003 and 2004-2019, respectively.

CONCLUSION

Histopathology may refine response prediction to IST. The course of SAA in children, a previously fatal disease, was altered in recent times.

Infections in Children With Cancer: The Role of the Presence or Absence of Neutropenia

BACKGROUND

Infections in patients with cancer are a major cause of morbidity and mortality. In most cases, the presence of neutropenia renders them prone to infections to either common or opportunistic pathogens. A wide spectrum of bacterial, viral, or fungal agents is encountered in these patients.

AIM

The aim of this study was to evaluate infection types and pathogens in pediatric patients with cancer with and without neutropenia.

METHODS

A total of 37 pediatric patients with cancer (median age ± 25% quartile, 6.0 ± 2.0% years) with 70 febrile episodes were evaluated at fever's onset and 48 hours later with complete blood count, C-reactive protein, cultures of biological fluids, polymerase chain reaction, and antibody titers.

RESULTS

Of 70 infections, 30 (42.85%) were bacterial, 13 (18.57%) were viral, 3 (4.28%) were fungal, 16 (22.85%) were fever of unknown origin, 18 (25.71%) were opportunistic, and 12 (17.14%) were mixed infections. Neutropenia was detected in 42 (60.0%) of 70 febrile episodes, mainly in patients with hematological malignancies [odds ratio, 2.81 (0.96-8.22); P = 0.059]. Neutropenic patients had higher prevalence of mucocutaneous infections (47.6% vs 7.14%; P = 0.004). Herpes simplex virus 1 infections occurred only in the neutropenic group (14.3%).

CONCLUSIONS

Patients with cancer exhibited a high prevalence of bacterial (42.85%), opportunistic (25.7%), and mixed infections (17.14%). Patients with hematological malignancies and neutropenia presented higher frequency of mucocutaneous and herpes simplex virus 1 infections than the nonneutropenic ones.

Insights from the Greek experience of the use of Blinatumomab in pediatric relapsed and refractory acute lymphoblastic leukemia patients

Pediatric refractory or relapsed acute lymphoblastic leukemia (ALL) poses unique therapeutic challenges, with novel immunotherapy approaches offering potential cure opportunities. In this frame, the use of Blinatumomab may induce durable remissions, serving as a successful bridge to allogeneic hematopoietic stem cell transplantation (allo-HSCT). Herein, we retrospectively summarize the Greek experience on pediatric relapsed/refractory B-cell precursor ALL patients that were treated with Blinatumomab in a compassionate, off-label setting as an effort to achieve disease clearance and proceed to allo-HSCT. In our cohort of 9 patients, 6/9 (66.7%) responded to Blinatumomab, achieving complete morphological remission (CR) after the 1st cycle, while minimal/measurable residual disease (MRD)-negativity (<10-4) after the 1st cycle was achieved in 2/2 patients (100.0%) with prior CR. A successful bridge to HSCT was feasible in 5/9 patients (55.6%). Median relapse-free survival (RFS) was 3.0 months (range 0.5-21.4 months) and median overall survival (OS) was 8.7 months (range 1.4-47.1 months) for the whole pediatric cohort. There was a trend of prolonged survival among patients who achieved MRD response after the 1st Blinatumomab administration. MRD response (defined as the >=2-log reduction of MRD value before and after Blinatumomab administration), was associated with a median RFS/OS of 7.4/7.6 months, while lack of MRD response was associated with a median RFS/OS of 0.5/3.0 months, respectively. Novel therapeutic maneuvers, in order to overcome disease resistance, i.e. increased usage of Blinatumomab dose (45 μg/m2/day), combination with donor lymphocyte infusions (DLIs), use of other immunotherapy salvage approaches (inotuzumabozogamicin), are herein discussed. Additionally, the optimal number of Blinatumomab cycles, the CD19-negative relapses and lineage switch, are also addressed. Our data although referred to a limited, however refractory or relapsed and heavily pretreated number of patients, strongly suggest that Blinatumomab may well induce sustained remissions and serve as an effective bridge to HSCT. Whether immunotherapy combined with chemotherapy can outweigh the need for subsequent allo-HSCT, if incorporated into frontline high-risk ALL therapy, remains an optimistic issue to be verified in future randomized clinical trials.

Interference of bone marrow CD56+ mesenchymal stromal cells in minimal residual disease investigation of neuroblastoma and other CD45- /CD56+ pediatric malignancies using flow cytometry

BACKGROUND

Bone marrow (BM) samples obtained from minimal residual disease (MRD)-negative children with B-cell acute lymphoblastic leukemia (B-ALL) were used in our laboratory as negative biological controls for the development of a neuroblastoma (NBL) flow-cytometric (FC) protocol. The accidental, but systematic, identification of rare cell populations (RCP) mimicking NBL cells (CD45^- /CD56⁺ ) in these samples indicated the need for their thorough immunophenotypic identification, in order to elucidate their possible interference in NBL-MRD assessment.

PROCEDURE

RCP observed in BM samples from 14 children recovering from BM aplasia due to intensive chemotherapy for B-ALL were investigated with the following markers: CD81, CD200, CD24, GD2, CD73, CD13, CD90, CD146, CD9, CD117, CD10, CD99, and NG2. BM samples from six newly diagnosed patients with NBL and an NBL cell line were simultaneously investigated as positive controls.

RESULTS

The frequency of RCP in B-ALL BM samples was < 1/1 × 10⁴ cells (bulky lysis), and their immunophenotypic profile was indicative of CD56⁺ mesenchymal stromal cells (MSCs) (CD45^- , CD90⁺ , CD146⁺ , CD73⁺ ). Also, RCP expressed CD81 and CD200, simulating NBL cells. The most useful discriminative markers for CD56⁺ MSCs were CD13 and CD73. An appropriate protocol consisting of two tubes with seven color combinations was further proposed: SYTO-16, GD2 (first tube) or CD73 (second tube)-PE, CD24-ECD, CD13-PC5.5, CD45-PC7, CD81-APC, and CD56-APC700.

CONCLUSIONS

RCP that were immunophenotypically similar to NBL were identified as CD56⁺ MSCs. As these cells might pose an obstacle to accurate NBL disease assessment by FC, especially MRD, an enhanced NBL-FC protocol is proposed for prospective evaluation.

BAFF/APRIL System Is Functional in B-Cell Acute Lymphoblastic Leukemia in a Disease Subtype Manner

BAFF, APRIL and their receptors regulate the survival, maturation and homeostasis of mature B-cells. Despite the lack of a functional role of BAFF/APRIL system during normal early B-cell development, previous studies indicated a contribution of these molecules in the pathogenesis of B-lineage acute lymphoblastic leukemia (B-ALL). Here, we evaluated the expression of this system in B-ALL and its involvement in spontaneous and drug-induced apoptosis of B-lymphoblasts, taking into consideration the distinct disease subtypes. We found that BAFFR is the most predominant aberrantly expressed receptor in B-ALL and that its expression, along with BCMA and APRIL, positively correlates with the maturation stage of B-lymphoblasts. Moreover, the binding of the E2A-PBX1 chimeric protein to the BAFFR promoter suggests that the transcriptional activator promotes the increase in BAFFR expression observed in about 50% of pre-B-ALL patients carrying the t _{(1, 19)} translocation. BAFF binding to BAFFR led to the processing of NF-κB2 p100 in pre-B ALL cells suggesting that BAFFR can activate the NF-κB2 pathway in pre-B ALL cells. Surprisingly, we found that BAFF treatment promotes the cell death of primary BCR-ABL⁺ BAFFR⁺ pre-B-lymphoblasts in adult B-ALL. It also enhances glucocorticoid-induced apoptosis in the E2A-PBX1⁺ pre-B-ALL cell line 697. These data suggest that BAFF/BAFFR signaling in B-ALL cells differs from normal B cells and that it may affect the pathogenesis of the disease.

A prospective study on the epidemiology and clinical significance of viral respiratory infections among pediatric oncology patients

Respiratory infections in oncology are both common and potentially severe. However, there is still a gap in the literature, regarding the epidemiology of viral respiratory infections in children with cancer. We prospectively enrolled 224 patients, from September 2012 to August 2015. The cohort included children with hematologic or solid malignancies receiving chemotherapy, or undergoing hemopoietic stem cell transplantation, outpatients/inpatients exhibiting signs/symptoms of febrile/afebrile upper/lower respiratory infection. Viral infection was diagnosed by detection of ≥1 viruses from a sample at time of enrollment, using the CLART^® PneumoVir kit (GENOMICA, Spain). Α detailed questionnaire including demographics and medical history was also completed. Samples were processed in batches, results were communicated as soon as they became available. Children recruited in whom no virus was detected composed the no virus detected group. Viral prevalence was 38.4% in children presenting with respiratory illness. A single virus was found in 30.4%, with RSV being the most frequent. Viral coinfections were detected in 8%. Children with viral infection were more likely to be febrile upon enrollment and to present with lower respiratory signs/symptoms. They had longer duration of illness and they were more likely to receive antibiotics/antifungals. Only 22% of children with influenza received oseltamivir. Mortality was low (2.7%), however, pediatric intensive care unit (PICU) admission and death were correlated with virus detection. In our study mortality was low and PICU admission was related to virus identification. Further research is needed to clarify whether antibiotics in virus-proven infection are of value and underline the importance of oseltamivir's timely administration in influenza.

Perinatal and early life risk factors for childhood brain tumors: Is instrument-assisted delivery associated with higher risk?

BACKGROUND

The childhood peak of brain tumors suggests that early-life exposures might have a role in their etiology. Hence, we examined in the Greek National Registry for Childhood Hematological Malignancies and Solid tumors (NARECHEM-ST) whether perinatal and early-life risk factors influence the risk of childhood brain tumors.

METHODS

In a nationwide case-control study, we included 203 cases (0-14 years) with a diagnosis of brain tumor in NARECHEM-ST (2010-2016) and 406 age-, sex-, and center-matched hospital controls. Information was collected via interviews with the guardians and we analyzed the variables of interest in multivariable conditional logistic regression models.

RESULTS

Instrument-assisted delivery was associated with higher (OR: 7.82, 95%CI: 2.18-28.03), whereas caesarean delivery with lower (OR: 0.67, 95%CI: 0.45-0.99) risk of childhood brain tumors, as compared to spontaneous vaginal delivery. Maternal alcohol consumption during pregnancy (OR: 2.35, 95%CI: 1.45-3.81) and history of living in a farm (OR: 4.98, 2.40-10.32) increased the odds of childhood brain tumors. Conversely, higher birth order was associated with lower risk (OR for 2nd vs. 1st child: 0.60, 95%CI: 0.40-0.89 and OR for 3^rd vs. 1^st: 0.34, 95%CI: 0.18-0.63). Birth weight, gestational age, parental age, history of infertility, smoking during pregnancy, allergic diseases, and maternal diseases during pregnancy showed no significant associations.

CONCLUSIONS

Perinatal and early-life risk factors, and specifically indicators of brain trauma, exposure to toxic agents and immune system maturation, might be involved in the pathogenesis of childhood brain tumors. Larger studies should aim to replicate our findings and examine associations with tumor subtypes.

ETV6/RUNX1-positive childhood acute lymphoblastic leukemia (ALL): The spectrum of clonal heterogeneity and its impact on prognosis

The prognostic significance of the ETV6/RUNX1-fusion and of the accompanying aberrations is disputable; whether co-existing sub-clones are responsible for delayed MRD-clearance and thus, moderate outcome, remains to be clarified. We studied, in a paediatric cohort of 119 B-ALLs, the relation between the ETV6/RUNX1 aberration and the co-existing subclones with (a) presenting clinical/biological features, (b) early response to treatment(MRD) and (c) long-term outcome over a 12-year period. Patients were homogeneously treated according to BFM-based-protocols. 27/119 patients (22.7%) were ETV6/RUNX1-positive; 19/27 (70.4%) harbored additional genetic abnormalities while 9/19 (33.3%) presented with clonal heterogeneity. The most common abnormalities were del12p13 (37%), 3-6×21q22 (22.2%), del9p21 (18.5%) and 2-3xETV6/RUNX1 (18.5%). MRDd15-positivity (≥10-3) was detected in 44% of the cohort; the corresponding MRD among patients carrying subclones rises to 88.9%. Common features of all relapses were sub-clonal diversity, FCM-MRDd15-positivity and additional del(9p21) while there were no censored relapses among ETV6/RUNX1-positive patients with sole translocation and absence of additional aberrations, within a median follow-up time of 90 months. In our study, the presence of clonal heterogeneity and impaired FCM-MRD clearance among ETV6/RUNX1-positive patients, ultimately influenced prognosis. Longer follow-up is needed in order to further validate these initial results.

Persisting inequalities in survival patterns of childhood neuroblastoma in Southern and Eastern Europe and the effect of socio-economic development compared with those of the US

AIM

Neuroblastoma outcomes vary with disease characteristics, healthcare delivery and socio-economic indicators. We assessed survival patterns and prognostic factors for patients with neuroblastoma in 11 Southern and Eastern European (SEE) countries versus those in the US, including-for the first time-the Nationwide Registry for Childhood Hematological Malignancies and Solid Tumours (NARECHEM-ST)/Greece.

METHODS

Overall survival (OS) was calculated in 13 collaborating SEE childhood cancer registries (1829 cases, ∼1990-2016) and Surveillance, Epidemiology, and End Results (SEER), US (3072 cases, 1990-2012); Kaplan-Meier curves were used along with multivariable Cox regression models assessing the effect of age, gender, primary tumour site, histology, Human Development Index (HDI) and place of residence (urban/rural) on survival.

RESULTS

The 5-year OS rates varied widely among the SEE countries (Ukraine: 45%, Poland: 81%) with the overall SEE rate (59%) being significantly lower than in SEER (77%; p < 0.001). In the common registration period within SEE (2000-2008), no temporal trend was noted as opposed to a significant increase in SEER. Age >12 months (hazard ratio [HR]: 2.8-4.7 in subsequent age groups), male gender (HR: 1.1), residence in rural areas (HR: 1.3), living in high (HR: 2.2) or medium (HR: 2.4) HDI countries and specific primary tumour location were associated with worse outcome; conversely, ganglioneuroblastoma subtype (HR: 0.28) was associated with higher survival rate.

CONCLUSIONS

Allowing for the disease profile, children with neuroblastoma in SEE, especially those in rural areas and lower HDI countries, fare worse than patients in the US, mainly during the early years after diagnosis; this may be attributed to presumably modifiable socio-economic and healthcare system performance differentials warranting further research.

Mortality and survival patterns of childhood lymphomas: geographic and age-specific patterns in Southern-Eastern European and SEER/US registration data

Childhood (0-14 years) lymphomas, nowadays, present a highly curable malignancy compared with other types of cancer. We used readily available cancer registration data to assess mortality and survival disparities among children residing in Southern-Eastern European (SEE) countries and those in the United States. Average age-standardized mortality rates and time trends of Hodgkin (HL) and non-Hodgkin (NHL; including Burkitt [BL]) lymphomas in 14 SEE cancer registries (1990-2014) and the Surveillance, Epidemiology, and End Results Program (SEER, United States; 1990-2012) were calculated. Survival patterns in a total of 8918 cases distinguishing also BL were assessed through Kaplan-Meier curves and multivariate Cox regression models. Variable, rather decreasing, mortality trends were noted among SEE. Rates were overall higher than that in SEER (1.02/106 ), which presented a sizeable (-4.8%, P = .0001) annual change. Additionally, remarkable survival improvements were manifested in SEER (10 years: 96%, 86%, and 90% for HL, NHL, and BL, respectively), whereas diverse, still lower, rates were noted in SEE. Non-HL was associated with a poorer outcome and an amphi-directional age-specific pattern; specifically, prognosis was inferior in children younger than 5 years than in those who are 10 to 14 years old from SEE (hazard ratio 1.58, 95% confidence interval 1.28-1.96) and superior in children who are 5 to 9 years old from SEER/United States (hazard ratio 0.63, 95% confidence interval 0.46-0.88) than in those who are 10 to 14 years old. In conclusion, higher SEE lymphoma mortality rates than those in SEER, but overall decreasing trends, were found. Despite significant survival gains among developed countries, there are still substantial geographic, disease subtype-specific, and age-specific outcome disparities pointing to persisting gaps in the implementation of new treatment modalities and indicating further research needs.

Association of maternal and index child's diet with subsequent leukemia risk: A systematic review and meta analysis

BACKGROUND

Exploring the effect of maternal and/or childhood diet on offspring leukemogenesis is challenging, given differences in food group categories, their potentially variable impact depending on time window of exposure and the multiple leukemia subtypes. We opted to quantitatively synthesize published data on the association of maternal/child diet with leukemia risk.

METHODS

Medline was searched until June 30th, 2016 for eligible articles on the association of childhood leukemia with consumption of (i) food groups, excluding alcoholic and non-alcoholic beverages, and (ii) specific dietary supplements before/during index pregnancy and childhood.

RESULTS

Eighteen studies of case-control design (N=11,720 cases/18,721 controls) were included, of which nine assessed maternal dietary components, five index child's and four both, mainly focusing on acute lymphoblastic leukemia (ALL). Statistically significant inverse estimates for ALL were found (2 studies, 413 cases, 490 controls) for fruit (OR: 0.81, 95% CI: 0.67, 0.99); vegetables (OR: 0.51, 95% CI: 0.28, 0.94); legumes (OR: 0.76, 95% CI: 0.62, 0.94); fish (OR: 0.27, 95% CI: 0.14, 0.53, among the 0-4year old; 2 studies 215 cases, 215 controls); preconception folic acid supplementation (OR: 0.69, 95%CI: 0.50-0.95; published meta analysis plus 2 studies, 3511 cases, 6816 controls); and use of vitamins during pregnancy (OR: 0.81, 95%CI: 0.74-0.88; published meta analysis plus one study, 5967 cases, 8876 controls). The associations (2 studies) of the remaining food groups and maternal dietary supplements consumption during pregnancy as well as of childhood diet and supplements intake (2-4 studies) were non significant.

CONCLUSIONS

Maternal consumption of specific food groups comprising"healthy" items of the Mediterranean diet, preconception use of folic acid and intake of vitamins during pregnancy were associated with decreased ALL risk. Further research is needed, however preferably with homogeneous dietary information and data on immunophenotypic/cytogenetic subtypes to also explore the interaction of specific macro- and micronutrients intake with gene polymorphisms.

Cognitive and socio-emotional development and manifestation of learning disabilities of 8- to 10-year-old children born after intracytoplasmatic sperm injection compared to naturally conceived children

OBJECTIVE

The purpose of the present study was to investigate the cognitive and socio-emotional development, as well as the mani- festation of learning disabilities of eight- to ten-year-old children born after intracytoplasmatic sperm injection (ICSI).

MATERIALS AND METHODS

Developmental outcomes of 40 children born after ICSI were compared with those of 40 children born after spontaneous conception (SC). Outcome measures included the Raven's Progressive Matrices Test, Child Behavior Checklist (CBCL), and Athina Test of Learning Difficulties.

RESULTS

Regarding cognitive development, ICSI children tend to obtain a similar intelligence score with SC children on Raven's Test. No significant differences were noted on CBCL's syndrome and abilities' profiles, and on Athina Test.

CONCLUSIONS

ICSI and SC children show a comparable cognitive and socio-emotional development and have the same chances of manifesting learning disabilities. None of the demographic factors taken into consideration (age, sex of the child, and educational level of the parents) nor the mode of conception seem to affect their well-being.

Survival trends in childhood chronic myeloid leukaemia in Southern-Eastern Europe and the United States of America

AIM

To assess trends in survival and geographic disparities among children (0-14 years) with chronic myeloid leukaemia (CML) before and after the introduction of molecular therapy, namely tyrosine kinase inhibitors (TKIs) in Southern-Eastern European (SEE) countries and the USA.

METHODS

We calculated survival among children with CML, acute lymphoblastic (ALL) and acute myeloid leukaemia (AML) in 14 SEE (1990-2014) cancer registries and the U.S. Surveillance, Epidemiology and End Results Program (SEER, 1990-2012). We used Kaplan-Meier curves and multivariate Cox regression models to calculate hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

Among 369 CML cases, substantial improvements were noted in 2-year survival during the post-TKI (range: 81-89%) compared to pre-TKI period (49-66%; HR: 0.37, 95% CI: 0.23-0.60). Risk of death was three times higher for <5-year-old children versus those aged 10-14 years (HR: 3.03, 95% CI: 1.85-4.94) and 56% higher for those living in SEE versus SEER (HR: 1.56, 95% CI: 1.01-2.42). Regardless of geographic area and period of TKI administration, however, age seems to be a significant determinant of CML prognosis (pre-TKI period, HR_0-4y: 2.71, 95% CI: 1.53-4.79; post-TKI period, HR_0-4y: 3.38, 95% CI: 1.29-8.85). Noticeably, post-TKI survival in CML overall approximates that for ALL, whereas therapeutic advancements for AML remain modest.

CONCLUSION

Registry data show that introduction of molecular therapies coincides with revolutionised therapeutic outcomes in childhood CML entailing dramatically improved survival which is now similar to that in ALL. Given that age disparities in survival remain substantial, offering optimal therapy to entire populations is an urgent priority.

B-cell acute lymphoblastic leukemia with mature phenotype and MLL rearrangement: report of five new cases and review of the literature

The association between mature-B phenotype and MLL abnormalities in acute lymphoblastic leukemia (ALL) is a very unusual finding; only 14 pediatric cases have been reported so far. We describe the clinical and biological characteristics and outcome of five pediatric cases of newly diagnosed B lineage ALL with MLL abnormalities and mature immunophenotype based on light chain restriction and surface Ig expression. Blasts showed variable expression of CD10/CD34/TdT. MLL abnormalities with no MYC involvement were detected in all patients by G-banding, FISH, and/or RT-PCR. Three patients were treated according to Interfant protocol, one to ALLIC-09, and one received B-NHL-BFM-2004. All patients achieved complete remission and three of them relapsed. Despite the small cohort size, it could be postulated that B lineage ALL with MLL abnormalities and mature phenotype is a distinct entity that differs both from the typical Pro B ALL observed in infants and mature B-ALL with high MYC expression.

Childhood central nervous system tumour mortality and survival in Southern and Eastern Europe (1983-2014): Gaps persist across 14 cancer registries

AIM

Childhood central nervous system (CNS) tumour registration and control programs in Southern and Eastern Europe remain thin, despite the lethal nature of the disease. Mortality/survival data were assembled to estimate the burden of malignant CNS tumours, as well as the potential role of sociodemographic survival determinants across 14 cancer registries of this region.

METHODS

Average age-adjusted mortality rates were calculated, whereas time trends were quantified through Poisson and Joinpoint regressions. Kaplan-Meier curves were derived for the maximum and the more recent (10 and 5 year) registration periods. Multivariate Cox regression models were used to assess demographic and disease-related determinants.

RESULTS

Variations in mortality (8-16 per million) and survival (5-year: 35-69%) were substantial among the participating registries; in most registries mortality trend was stable, whereas Bulgaria, having the highest starting rate, experienced decreasing annual mortality (-2.4%, p=0.001). A steep decrease in survival rates was evident before the second year of follow-up. After controlling for diagnostic subgroup, age, gender and diagnostic year, Greece seemed to present higher survival compared with the other contributing registries, although the follow-up period was short. Irrespective of country, however, rural residence was found to impose substantial adverse repercussions on survival (hazard ratio (HR): 1.2, 95% confidence interval (CI): 1.1-1.4).

CONCLUSION

Cross-country mortality and survival variations possibly reflect suboptimal levels of health care delivery and cancer control in some regions of Southern and Eastern Europe, notwithstanding questionable death certification patterns or follow-up procedures. Continuous childhood cancer registration and linkage with clinical data are prerequisite for the reduction of survival inequalities across Europe.

History of Maternal Fetal Loss and Childhood Leukaemia Risk in Subsequent Offspring: Differentials by Miscarriage or Stillbirth History and Disease Subtype

BACKGROUND

Despite the putative intrauterine origins of childhood (0-14 years) leukaemia, it is complex to assess the impact of perinatal factors on disease onset. Results on the association of maternal history of fetal loss (miscarriage/stillbirth) with specific disease subtypes in the subsequent offspring are in conflict. We sought to investigate whether miscarriage and stillbirth may have different impacts on the risk of acute lymphoblastic leukaemia (ALL) and of its main immunophenotypes (B-cell and T-cell ALL), as contrasted to acute myeloid leukaemia (AML).

METHODS

One thousand ninety-nine ALL incidents (957 B-ALL) and 131 AML cases along with 1:1 age and gender-matched controls derived from the Nationwide Registry for Childhood Hematological Malignancies and Brain Tumors (1996-2013) were studied. Multivariable regression models were used to assess the roles of previous miscarriage(s) and stillbirth(s) on ALL (overall, B-, T-ALL) and AML, controlling for potential confounders.

RESULTS

Statistically significant exposure and disease subtype-specific associations of previous miscarriage(s) exclusively with AML [odds ratio (OR) 1.67, 95% confidence interval (CI) 1.00, 2.81] and stillbirth(s) with ALL [OR 4.82, 95% CI 1.63, 14.24] and B-ALL particularly, emerged.

CONCLUSION

Differential pathophysiological pathways pertaining to genetic polymorphisms or cytogenetic aberrations are likely to create hostile environments leading either to fetal loss or the development of specific leukaemia subtypes in subsequent offspring, notably distinct associations of maternal miscarriage history confined to AML and stillbirth history confined to ALL (specifically B-ALL). If confirmed and further supported by studies revealing underlying mechanisms, these results may shed light on the divergent leukemogenesis processes.

Maternal and childhood consumption of coffee, tea and cola beverages in association with childhood leukemia: a meta-analysis

OBJECTIVE

To systematically review studies and meta-analyze the literature on the association of maternal and/or index child's coffee, tea, and cola consumption with subsequent development of childhood leukemia and its major subtypes.

METHODS

Eligible studies were identified through a detailed algorithm and hand-search of eligible articles' references; thereafter, summary-effect estimates were calculated by leukemia subtype and dose-response meta-analyses were performed.

RESULTS

Twelve case-control studies, comprising a total of 3649 cases and 5705 controls, were included. High maternal coffee consumption was positively associated with acute lymphoblastic leukemia (ALL; OR: 1.43, 95%CI: 1.22-1.68) and acute myeloid leukemia (AML; OR: 2.52, 95%CI: 1.59-3.57). Any or low to moderate maternal cola consumption was also positively associated with overall leukemia (AL) and ALL, A linear trend between coffee and cola consumption and childhood leukemia was observed in the dose-response analyses. On the contrary, low to moderate tea consumption was inversely associated with AL (OR: 0.85, 95%CI: 0.75-0.97), although the trend was non-significant. A null association between offspring's cola consumption and leukemia was noted.

CONCLUSIONS

Our findings confirm the detrimental association between maternal coffee consumption and childhood leukemia risk and provide indications for a similar role of maternal cola intake. In contrast, an inverse association with tea was found, implying that other micronutrients contained in this beverage could potentially counterbalance the deleterious effects of caffeine. Further research should focus on the intake of specific micronutrients, different types of coffee and tea, specific immunophenotypes of the disease, and the modifying effect of genetic polymorphisms.

Childhood central nervous system tumours: Incidence and time trends in 13 Southern and Eastern European cancer registries

AIM

Following completion of the first 5-year nationwide childhood (0-14 years) registration in Greece, central nervous system (CNS) tumour incidence rates are compared with those of 12 registries operating in 10 Southern-Eastern European countries.

METHODS

All CNS tumours, as defined by the International Classification of Childhood Cancer (ICCC-3) and registered in any period between 1983 and 2014 were collected from the collaborating cancer registries. Data were evaluated using standard International Agency for Research on Cancer (IARC) criteria. Crude and age-adjusted incidence rates (AIR) by age/gender/diagnostic subgroup were calculated, whereas time trends were assessed through Poisson and Joinpoint regression models.

RESULTS

6062 CNS tumours were retrieved with non-malignant CNS tumours recorded in eight registries; therefore, the analyses were performed on 5191 malignant tumours. Proportion of death certificate only cases was low and morphologic verification overall high; yet five registries presented >10% unspecified neoplasms. The male/female ratio was 1.3 and incidence decreased gradually with age, apart from Turkey and Ukraine. Overall AIR for malignant tumours was 23/10(6) children, with the highest rates noted in Croatia and Serbia. A statistically significant AIR increase was noted in Bulgaria, whereas significant decreases were noted in Belarus, Croatia, Cyprus and Serbia. Although astrocytomas were overall the most common subgroup (30%) followed by embryonal tumours (26%), the latter was the predominant subgroup in six registries.

CONCLUSION

Childhood cancer registration is expanding in Southern-Eastern Europe. The heterogeneity in registration practices and incidence patterns of CNS tumours necessitates further investigation aiming to provide clues in aetiology and direct investments into surveillance and early tumour detection.