PersonALL: a genetic scoring guide for personalized risk assessment in pediatric B-cell precursor acute lymphoblastic leukemia.

BACKGROUND: Recurrent genetic lesions provide basis for risk assessment in pediatric acute lymphoblastic leukemia (ALL). However, current prognostic classifiers rely on a limited number of predefined sets of alterations. METHODS: Disease-relevant copy number aberrations (CNAs) were screened genome-wide in 260 children with B-cell precursor ALL. Results were integrated with cytogenetic data to improve risk assessment. RESULTS: CNAs were detected in 93.8% (n = 244) of the patients. First, cytogenetic profiles were combined with IKZF1 status (IKZF1normal, IKZF1del and IKZF1plus) and three prognostic subgroups were distinguished with significantly different 5-year event-free survival (EFS) rates, IKAROS-low (n = 215): 86.3%, IKAROS-medium (n = 27): 57.4% and IKAROS-high (n = 18): 37.5%. Second, contribution of genetic aberrations to the clinical outcome was assessed and an aberration-specific score was assigned to each prognostically relevant alteration. By aggregating the scores of aberrations emerging in individual patients, personalized cumulative values were calculated and used for defining four prognostic subgroups with distinct clinical outcomes. Two favorable subgroups included 60% of patients (n = 157) with a 5-year EFS of 96.3% (excellent risk, n = 105) and 87.2% (good risk, n = 52), respectively; while 40% of patients (n = 103) showed high (n = 74) or ultra-poor (n = 29) risk profile (5-year EFS: 67.4% and 39.0%, respectively). CONCLUSIONS: PersonALL, our conceptually novel prognostic classifier considers all combinations of co-segregating genetic alterations, providing a highly personalized patient stratification.

Daily serum phosphate increase as early and reliable indicator of kidney injury in children with leukemia and lymphoma developing tumor lysis syndrome.

BACKGROUND: Tumor lysis syndrome (TLS) and its most serious complication, acute kidney injury (AKI) are one of the emergency conditions in onco-hematology. It is difficult to predict the degree of kidney involvement. Therefore, we studied children with leukemia and lymphoma treated in four Hungarian tertiary centers (inpatient university clinics) retrospectively (2006-2016) from a nephrological aspect. METHOD: Data of 31 pediatric patients were obtained from electronic- and paper-based medical records. Physical status, laboratory test results, treatments, and outcomes were assessed. Patients were analyzed according to both "traditional" TLS groupings, as laboratory TLS or clinical TLS, and nephrological aspect based on pRIFLE classification, as mild or severe AKI. RESULTS: Significant differences were found between the changes in parameters of phosphate homeostasis and urea levels in both classifications. Compared to age-specific normal phosphate ranges, before the development of TLS, hypophosphatemia was common (19/31 cases), while in the post-TLS period, hyperphosphatemia was observed (26/31 cases) most frequently. The rate of daily change in serum phosphate level was significant in the nephrological subgroups, but peaks of serum phosphate level show only a moderate increase. The calculated cut-off value of daily serum phosphate level increased before AKI was 0.32 mmol/L per ROC analysis for severe TLS-AKI. The 24-h urinalysis data of eight patients revealed transiently increased phosphate excretion only in those patients with TLS in whom serum phosphate was elevated in parallel. CONCLUSION: Daily serum phosphate level increase can serve as a prognostic factor for the severity of pediatric TLS, as well as predict the severity of kidney involvement. A higher resolution version of the Graphical abstract is available as Supplementary information.

Alterations of miRNA Expression in Diffuse Hyperplastic Perilobar Nephroblastomatosis: Mapping the Way to Understanding Wilms' Tumor Development and Differential Diagnosis.

Wilms' tumor (WT) is the most common renal malignancy in children. In diffuse hyperplastic perilobar nephroblastomatosis (DHPLN), nephrogenic rests result in a bulky enlargement of the kidney, a condition considered as a premalignant state before WT. Despite relevant clinical differences between WT and DHPLN, they are often challenging to distinguish based on histology. Molecular markers would improve differential diagnosis, but none are available at present. In our study, we investigated the potential of microRNAs (miRNAs) as such biomarkers, also aiming to shed light on the chronological order of expression changes. Formalin-fixed, paraffin-embedded (FFPE) samples from four DHPLN cases and adjacent healthy tissues were tested using a PCR array containing primers for 84 miRNAs implicated in genitourinary cancer. Expression in DHPLN was compared to WT data available in dbDEMC. Let-7, miR-135, miR-146a-5p, miR-182-5p, miR-183-5p, miR-20b-3p, miR-29b-3p, miR-195-5p and miR-17-5p showed potential to be used as biomarkers to distinguish WT and DHPLN in cases when traditional differential diagnosis is inconclusive. Our study also revealed miRNAs which may play a role in the initial steps of the pathogenesis (at a precancerous stage) and ones which become deregulated later in WT. More experiments are needed to confirm our observations and find new candidate markers.

Assessment of the results and hematological side effects of 3D conformal and IMRT/ARC therapies delivered during craniospinal irradiation of childhood tumors with a follow-up period of five years.

BACKGROUND: Craniospinal irradiation (CSI) of childhood tumors with the RapidArc technique is a new method of treatment. Our objective was to compare the acute hematological toxicity pattern during 3D conformal radiotherapy with the application of the novel technique. METHODS: Data from patients treated between 2007 and 2014 were collected, and seven patients were identified in both treatment groups. After establishing a general linear model, acute blood toxicity results were obtained using SPSS software. Furthermore, the exposure dose of the organs at risk was compared. Patients were followed for a minimum of 5 years, and progression-free survival and overall survival data were assessed. RESULTS: After assessment of the laboratory parameters in the two groups, it may be concluded that no significant differences were detected in terms of the mean dose exposures of the normal tissues or the acute hematological side effects during the IMRT/ARC and 3D conformal treatments. Laboratory parameters decreased significantly compared to the baseline values during the treatment weeks. Nevertheless, no significant differences were detected between the two groups. No remarkable differences were confirmed between the two groups regarding the five-year progression-free survival or overall survival, and no signs of serious organ toxicity due to irradiation were observed during the follow-up period in either of the groups. CONCLUSION: The RapidArc technique can be used safely even in the treatment of childhood tumors, as the extent of the exposure dose in normal tissues and the amount of acute hematological side effects are not higher with this technique.

Extraskeletal, intradural, non-metastatic Ewing's sarcoma. Case report.

Intracranial localization of Ewing's sarcoma is considerably very rare. Herein, we present clinical and neuroimaging findings regarding a 4-year-old boy with intracranial Ewing's sarcoma. He was born prematurely, suffered intraventricular haemorrhage, posthaemorrhagic hydrocephalus developed, and a ventriculoperitoneal shunt was inserted in the newborn period. The patient endured re-gular follow ups, no signs of shunt malfunction nor increased intracranial pressure were observed. The last neuroima-ging examination was performed at 8 months of age. Upon reaching the age of 4 years, repeated vomiting and focal seizures began, and symptoms of increased intracranial pressure were detected. A brain MRI depicted a left frontoparietal space-occupying lesion infiltrating the superior sagittal sinus. The patient underwent a craniotomy resulting in the total excision of the tumour. The histological examination of the tissue revealed a small round blue cell tumour. The diagnosis was confirmed by the detection of EWSR1 gene translocation with FISH (fluorescent in situ hybridization). No additional metastases were detected during the staging examinations. The patient was treated in accordance to the EuroEwing 99 protocol. Today, ten years onward, the patient is tumour and seizure free and has a reasonably high quality of life.

Possible roles of genetic variations in chemotherapy related cardiotoxicity in pediatric acute lymphoblastic leukemia and osteosarcoma.

BACKGROUND: The treatment of acute lymphoblastic leukemia (ALL) and osteosarcoma (OSC) is very effective: the vast majority of patients recover and survive for decades. However, they still need to face serious adverse effects of chemotherapy. One of these is cardiotoxicity which may lead to progressive heart failure in the long term. Cardiotoxicity is contributed mainly to the use of anthracyclines and might have genetic risk factors. Our goal was to test the association between left ventricular function and genetic variations of candidate genes. METHODS: Echocardiography data from medical records of 622 pediatric ALL and 39 OSC patients were collected from the period 1989-2015. Fractional shortening (FS) and ejection fraction (EF) were determined, 70 single nucleotide polymorphisms (SNPs) in 26 genes were genotyped. Multivariate logistic regression and multi-adjusted general linear model were performed to investigate the influence of genetic polymorphisms on the left ventricular parameters. Bayesian network based Bayesian multilevel analysis of relevance (BN-BMLA) method was applied to test for the potential interaction of the studied cofactors and SNPs. RESULTS: Our results indicate that variations in ABCC2, CYP3A5, NQO1, SLC22A6 and SLC28A3 genes might influence the left ventricular parameters. CYP3A5 rs4646450 TT was 17% among ALL cases with FS lower than 28, and 3% in ALL patients without pathological FS (p = 5.60E-03; OR = 6.94 (1.76-27.39)). SLC28A3 rs7853758 AA was 12% in ALL cases population, while only 1% among controls (p = 6.50E-03; OR = 11.56 (1.98-67.45)). Patients with ABCC2 rs3740066 GG genotype had lower FS during the acute phase of therapy and 5-10 years after treatment (p = 7.38E-03, p = 7.11E-04, respectively). NQO1 rs1043470 rare T allele was associated with lower left ventricular function in the acute phase and 5-10 years after the diagnosis (p = 4.28E-03 and 5.82E-03, respectively), and SLC22A6 gene rs6591722 AA genotype was associated with lower mean FS (p = 1.71E-03), 5-10 years after the diagnosis. CONCLUSIONS: Genetic variants in transporters and metabolic enzymes might modulate the individual risk to cardiac toxicity after chemotherapy.

[Change in paradigm in the treatment of pediatric acquired bone marrow failure syndromes in Hungary]. / Korszakváltás a gyermekkori szerzett csontvelo-elégtelenséggel járó kórképek kezelésében Magyarországon.

INTRODUCTION: Acquired bone marrow failures are rare but fatal diseases in childhood. Since 2013, Hungary has been participating as a full member in the work of the European Working Group on uniform diagnostics and therapy in patients with acquired bone marrow failure syndromes. Hypocellular refractory cytopenia of childhood has been emphasized as a frequent entity, transplanted by reduced intensity conditioning with excellent outcomes. AIM: To analyse and compare the results of treatment before and after our joining. METHOD: A total of 55 patients have been treated in the 8 centres of the Hungarian Pediatric Oncology Network during 5 years between 2013 and 2017 (severe aplastic anemia: 9, myelodysplastic syndrome: 41, juvenile myelomonocytic leukemia: 5 patients). Allogeneic hematopoietic stem cell transplantation was performed in severe aplastic anemia in 7 cases, while antithymocyte globulin was administered in one case and one patient died before diagnosis. In patients with myelodysplastic syndromes, watch and wait strategy was applied in 4, while transplantation in 37 cases. Reduced intensity conditioning was used in 54 percent of these cases. Transplantation was the treatment of choice in all 5 patients with juvenile myelomonocytic leukemia. RESULTS: In the whole patient cohort, the time from diagnosis to treatment was median 92 (3-393) days, while in severe aplastic anemia median 28 (3-327) days only. Grade II-IV acute graft versus host disease occurred in 22.6%, grade III-IV in 6.8% and chronic in 11.2%. All the patients treated with severe aplastic anemia are alive and in complete remission (100%). The overall estimated survival rate is 85.1% in myelodysplastic syndrome, while 75% in juvenile myelomonocytic leukemia. The median follow-up was 30.4 (1.1-62.5) months. There was a remarkable increase in overall survival comparing the data before (1992-2012) and after (2013) joining the international group, 70% vs. 100% (p = 0.133) in severe aplastic anemia and 31.3% vs. 85.1% (p = 0.000026) in myelodysplastic syndrome. CONCLUSION: Due to a change in the paradigm of the conditioning regimen in hypocellular refractory cytopenia of childhood, the overall survival rate has significantly increased. Orv Hetil. 2018; 159(42): 1710-1719.

Sequential and hierarchical chromosomal changes and chromosome instability are distinct features of high hyperdiploid pediatric acute lymphoblastic leukemia.

BACKGROUND: Pathogenesis of the non-random accumulation of extra chromosomes in the low and high hyperdiploid (HeL, HeH) pre-B pediatric acute lymphoblastic leukemia (B-pALL) is largely unknown, and has been clarified with respect only to tetrasomic chromosomes. We analyzed the hierarchy of changes in chromosome number and chromosomal instability, as well as clonal heterogeneity and evolution, in the untreated bone marrow cell samples from 214 B-pALL patients. PROCEDURE: Applying relocation, 2 × 4 color interphase fluorescence in situ hybridization was used to detect copy number alterations (CNAs) of the most commonly involved chromosomes, 4, 6, 10, 14, 17, 18, 21, and X. This approach allowed us to acquire a dataset correlated for all eight parameters. RESULTS: Based on chromosome number, an average of 6.9 and 10.2, whereas according to unique constellation 15.3 and 26.7 subclones could be identified in the HeL and HeH subgroups, respectively. Cluster analysis revealed the order of CNAs to chromosomes was highly conserved, and network analysis indicated changes in chromosome number were sequential for 80-90% of all numerical aberrations. Significant chromosome instability was revealed in both subgroups of leukemia. CONCLUSIONS: Data generated using this new approach indicate that chromosomal instability, which causes heterogeneity in the subclonal landscape, and the sequential changes to chromosome numbers, are both determining factors in the pathomechanism of the hyperdiploid B-pALL. These new observations could prompt research into the mitotic machinery of leukemic cells to identify new therapeutic targets for treating this disease.

Immunogenicity of a 2009 pandemic influenza virus A H1N1 vaccine, administered simultaneously with the seasonal influenza vaccine, in children receiving chemotherapy.

BACKGROUND: No examination of simultaneous vaccination against pandemic H1N1 and the seasonal influenza virus strains, in children with cancer receiving chemotherapy, are yet published. We investigated the immunogenicity of a whole-virion, inactivated, adjuvanted pandemic H1N1, and seasonal influenza vaccines administered simultaneously to children with cancer undergoing chemotherapy. PROCEDURE: We prospectively enrolled 27 pediatric patients receiving therapy for various types of cancer. All received influenza vaccination once in a seasonal risk period. We checked hemaglutination-inhibition (HAI) antibody titers in the sera of patients before, and 21-28 days after vaccination. Seroprotective titer was defined as an antibody titer ≥ 40, and seroresponse as ≥ 4-fold increase in antibody titers after vaccination. RESULTS: The pre- and post-vaccination seroprotective rates were H1N1: 33-48%, H3N2: 56-78%, B: 0-15% for seasonal influenza, and for pandemic H1N1: 15-37%. The seroresponse rates for seasonal influenza H1N1, H3N2, and B were 22%, 37%, and 22%, respectively, and 30% for the pandemic H1N1 vaccine. CONCLUSIONS: Whole-virion, inactivated, adjuvanted vaccine for the pandemic H1N1 Influenza A virus and the seasonal influenza vaccines were found safe and partially immunogenic in children with cancer receiving chemotherapy. The only determinants of responsiveness were lymphocyte count and serum immunoglobulin-G. Only influenza B vaccine elicited significant differences in differences in pre- and post-vaccination seroprotective rates. The response to vaccination for pandemic H1N1 is as effective as other vaccines, however administration of a single vaccine during chemotherapy is more comfortable for pediatric cancer patients.

The Impact of Qualification and Hospice Education on Staff Attitudes during Palliative Care in Pediatric Oncology Wards-A National Survey.

BACKGROUND: Our knowledge about the attitudes of healthcare staff to palliative care in pediatric oncology is scarce. We aimed to assess their perceptions of palliative care in Hungary and find answers to the question of how to provide good palliative care for children. METHOD: Physicians (n = 30) and nurses (n = 43) working in the field of pediatric oncology (12 of them specialized in hospice care) were interviewed. Palliative care practice (communication, integration of palliative care, professionals' feelings and attitudes, and opportunities for improvement) was assessed by semi-structured interviews evaluated in a mixed quantitative and qualitative way by narrative categorical content analysis and thematic analysis. RESULTS: All providers displayed high negative emotions, positive evaluations, and used many active verbs. Nurses showed higher levels of denial, more self-references, and were more likely to highlight loss. Physicians emphasized the importance of communication regarding adequate or inadequate palliative care. Hospice specialists showed a higher passive verb rate, a lower self-reference, a lower need for psychological support, and a greater emphasis on teamwork and professional aspects. CONCLUSION: Our results show that nurses are more emotionally stressed than doctors in palliative care in pediatric oncology. To our knowledge, a study comparing doctors and nurses in this field has yet to be carried out. Our results suggest that pediatric oncological staff can positively evaluate a child's palliative care despite the emotional strain. Regarding hospices, professional practice in palliative care may be a protective factor in reducing emotional distress and achieving professional well-being.

[Association of giant cell hepatitis and autoimmune hemolytic anemia in infancy]. / Óriássejtes hepatitis és autoimmun haemolyticus anaemia társulása kisdedkorban.

Giant cell hepatitis associated with autoimmune hemolytic anemia (GCH-AIHA) is a rare disorder with unfavorable prognosis, affecting infants and young children. The mortality rate is high, complications of acute liver failure, sepsis, or liver transplantation can be responsible for fatal outcomes. An 18-month-old child who was diagnosed previously with autoimmune hemolytic anemia, developed acute hepatitis and acute liver failure concomitant to the relapse of the disease. GCH-AIHA is characterized by Coombs positive hemolytic anemia and progressive liver injury, histologically defined by widespread giant cell transformation. Liver biopsy was performed to establish the diagnosis, histological examination confirmed the presence of multinuclear, giant cell hepatocytes. Corticosteroid and azathioprine treatment were started. As a result of subsequent rituximab treatment and intravenous immunoglobulin therapy, acute liver failure and anemia gradually resolved. The exact background of the association of the two entities is still unknown, an autoimmune mechanism is suspected. Conventional immunosuppressive treatment with corticosteroid and azathioprine seems to be ineffective in most cases, therefore second- and third-line therapies are required. Since the introduction of the anti-CD20 rituximab therapy, the prognosis of GCH-AIHA has improved significantly. Orv Hetil. 2023; 164(36): 1432-1436.

[131-I-meta-iodo-benzyl-guanidine therapy in childhood neuroblastoma.] / Gyermekkori neuroblastoma kezelésében alkalmazott 131-I-meta-jodo-benzil-guanidin terápia.

Neuroblastoma, representing one-tenth of childhood malignancies, is a clinically and prognostically heterogeneous disease. Survival in cases with poor prognosis has recently been significantly improved by rapidly evolving multimodal therapy. Our 4-year-old patient presented with bitemporal swelling and the diagnostic workup confirmed stage IV neuroblastoma (bone marrow and multiple bone metastases). While the tumor responded well to the initial treatment, it relapsed during post-consolidation therapy. As part of the salvage therapy for this high-risk disease with poor prognosis, 131-I-meta-iodo-benzyl-guanidine treatment was performed for the first time in our country, in a case of pediatric neuroblastoma. Neuroendocrine tissue cells express a norepinephrine transporter capable of uptaking the catecholamine analog meta-iodo-benzyl-guanidine. This mechanism makes it an adequate molecule for the imaging (123-I-meta-iodo-benzyl-guanidine) and target therapy (131-I-meta-iodo-benzyl-guanidine) of neuroendocrine tumors, including neuroblastoma. Treatment with 131-I-meta-iodo-benzyl-guanidine requires specific personnel and infrastructural equipment, particularly in pediatric cases. Careful organization and cooperation between nuclear medicine specialists and collaborating clinicians (pediatric oncologists and adult internists if necessary) are essential. Meta-iodo-benzyl-guanidine therapy, already routinely used abroad, has been considered as part of salvage therapy for recurrent neuroblastoma until now, but ongoing clinical trials suggest that it may become part of the first-line treatment soon. As the indications broaden, it is necessary to make it available for more and more children in our country. Orv Hetil. 2023; 164(39): 1550-1555.

Next-Generation Sequencing-Based Genomic Profiling of Children with Acute Myeloid Leukemia.

Pediatric acute myeloid leukemia (AML) represents a major cause of childhood leukemic mortality, with only a limited number of studies investigating the molecular landscape of the disease. Here, we present an integrative analysis of cytogenetic and molecular profiles of 75 patients with pediatric AML from a multicentric, real-world patient cohort treated according to AML Berlin-Frankfurt-Münster protocols. Targeted next-generation sequencing of 54 genes revealed 17 genes that were recurrently mutated in >5% of patients. Considerable differences were observed in the mutational profiles compared with previous studies, as BCORL1, CUX1, KDM6A, PHF6, and STAG2 mutations were detected at a higher frequency than previously reported, whereas KIT, NRAS, and KRAS were less frequently mutated. Our study identified novel recurrent mutations at diagnosis in the BCORL1 gene in 9% of the patients. Tumor suppressor gene (PHF6, TP53, and WT1) mutations were found to be associated with induction failure and shorter event-free survival, suggesting important roles of these alterations in resistance to therapy and disease progression. Comparison of the mutational landscape at diagnosis and relapse revealed an enrichment of mutations in tumor suppressor genes (16.2% versus 44.4%) and transcription factors (35.1% versus 55.6%) at relapse. Our findings shed further light on the heterogeneity of pediatric AML and identify previously unappreciated alterations that may lead to improved molecular characterization and risk stratification of pediatric AML.

Medical Communication during the Transition to Palliative Care in Pediatric Oncology in Hungary-The Parents' Perspective.

The transition to palliative care (PC) is a critical aspect of pediatric oncology, and it requires a high level of communication skills from doctors, which could be best judged by the parents of children who have died from cancer. Our aim was to explore the parents' perspectives regarding the timing of the consultation on the implementation of PC, as well as facets of verbal and nonverbal communication in Hungary. Semistructured interviews were conducted with parents who had lost a child to cancer within the past 1-5 years. Interview transcripts (n = 23) were scrutinized with interpretative phenomenological analysis. The parents frequently associated palliation with end-of-life care and they clearly delimited the transition to PC after curative treatments had been exhausted. The parents were ambivalent with regard to the use of the word "death" during this consultation, and they often did not receive information on what to expect (e.g., regarding symptoms) or on who to turn to for further information or support (e.g., concerning bereavement). Although significant progress could be observed in the organization of pediatric palliative care in Hungary, there is still no widely accepted communication method for the transition to sole PC. There is a need for a culturally sensitive approach to refining the recommendations on the word use and communication protocol in pediatric PC in Hungary.

Clinical Course of COVID-19 Disease in Children Treated With Neoplastic Diseases in Hungary.

We report on children with cancer in Hungary suffering from COVID-19, surveying a 13-months-long period of time. We performed a retrospective clinical trial studying the medical documentation of children treated in seven centers of the Hungarian Pediatric Oncology-Hematology Group. About 10% of children admitted to tertiary hemato-oncological centers for anti-neoplastic treatment or diagnosis for de novo malignancies were positive for SARS-CoV-2 infection. Nearly two-thirds of the infected patients were asymptomatic or had only mild symptoms but showed seropositivity by 1-4.5 months after positive PCR. One third of the SARS-CoV-2-positive children were hospitalized due to symptomatic COVID-19. Five children required antiviral treatment with remdesivir. One child was referred to the intensive care unit, requiring intubation and mechanical ventilation. Delay in the scheduled anti-cancer treatment did not exceed 2 weeks in the majority (89%) of cases. There was only one patient requiring treatment deferral longer than a month. There was no COVID-19-related death in patients under 18 years of age, and nor was multisystem inflammatory syndrome diagnosed. In conclusion, SARS-CoV-2 infection did not represent an untoward risk factor among children with cancer in Hungary.

[Unusual clinical manifestations of type 1 neurofibromatosis]. / Az 1-es típusú neurofibromatosis ritka megjelenésu, tanulságos esetei.

UNLABELLED: Type 1 neurofibromatosis is an autosomal dominant hamartosis caused by mutations of the neurofibromin-1 gene. The classic features of the clinical phenotype include the presence of café-au-lait spots, neurofibromas, axillary and inguinal freckling, Lisch-nodules and deformities of the skeletal system, as well as the risk of developing multiple tumors, especially in the central nervous system. However, it is known from the literature that the phenotypic variability can pose a huge diagnostic difficulty. AIMS: Our institute performs molecular genetic testing of the neurofibromin-1 gene since 2008; during this period several unusual phenotypic variants were found. RESULTS, CONCLUSION: The reported four cases represent interesting phenotypic variants or diagnostic challenges in which the final diagnosis was established by molecular genetic analysis.

Baseline CD3+CD56+ (NKT-like) Cells and the Outcome of Influenza Vaccination in Children Undergoing Chemotherapy.

Background: In children undergoing chemotherapy yearly influenza vaccination is recommended by treatment protocols. We investigated the relationship between cellular immunity and the antibody response to inactivated influenza vaccines. Methods: 25 patients (age: 2-18 years) undergoing chemotherapy for different malignancies participated in our study. Flow cytometric detection of peripheral blood lymphocyte subpopulations together with hemagglutination inhibition antibody titers were measured before and 21-28 days after vaccination. We examined the ratio and total numbers of CD3+, CD4+, CD8+ T cells, activated helper (CD3+CD4+CD25low), regulatory (CD3+CD4+CD25high), naive (CD3+CD45RA+) and memory (CD3+CD45RO+) T cells, CD56+NK, and CD3+CD56+ (NKT-like) cells. Relationships between specific antibody responses (seroprotection, seroconversion, geometric mean titer (GMT), geometric mean fold increase (GMFI)) and the ratios and counts of lymphocyte subpopulations were evaluated using one-way ANOVA and the paired sample t test after dichotomization according to age-related reference values. Results: Patients with CD4+ lymphocyte levels in the normal age-specific range showed significantly better response regarding postvaccination GMT elevation for H1N1 and H3N2 strains (97.52 vs. 19.2, p=0.019, 80 vs. 14.43, p=0.021, respectively). GMFI results were significant only against B strain (2.69-fold vs. 1.23-fold, p=0.046). Prevaccination CD3+CD56+ (NKT-like) cells above predicted values according to age showed significant associations both in postvaccination GMT elevation (H1N1: 75.11 vs. 14.14, p=0.010; H3N2: 62.18 vs. 11.22, p=0.012; B: 22.69 vs. 6.67, p=0.043) and GMFI against all three strains (H1N1: 3.76-fold vs. 1.06-fold, p=0.015; H3N2: 2.74-fold vs. 1, p=0.013; B: 2.57-fold vs. 1, p=0.008). By one-way ANOVA, we found a positive relation between absolute lymphocyte cell count above 1000/µl and the postvaccination GMT elevation against H3N2 (12.81 vs. 56.56, p=0.032), and GMFI regarding H1N1 (1.22-fold vs. 3.48-fold, p=0.044). Conclusions: In addition to verifying the predictive value of absolute lymphocyte count above 1000/µl, our results suggest an association between NKT-like cell counts and the specific antibody response against all three investigated influenza strains in highly immunosuppressed patients. Furthermore, prevaccination CD4+ lymphocyte levels in the normal age-specific range may influence seroresponse.

Detection of early precursors of t(12;21) positive pediatric acute lymphoblastic leukemia during follow-up.

DNA-, RNA-, and cell-based methods provide different biologic information for determining the presence of minimal residual disease (MRD). We monitored the responses of patients with pediatric acute lymphoblastic leukemia (pALL) using DNA markers, TEL/AML1 expression, and scanning fluorescence microscopy (SFM). Using SFM, 36% of patients exhibited 1.5-3.1 log and 2.9-4.2 log higher MRD levels compared with those based on DNA and RNA markers, respectively. CD10+ ancestor cells with germline antigen receptors, but silent TEL/AML1 expression, may reside in the lymphoid stem cell compartment of treated t(12;21)-positive patients and might act as a potential source of cells for late relapses.

Flash survey on severe acute respiratory syndrome coronavirus-2 infections in paediatric patients on anticancer treatment.

INTRODUCTION: Since the beginning of COVID-19 pandemic, it is known that the severe course of the disease occurs mostly among the elderly, whereas it is rare among children and young adults. Comorbidities, in particular, diabetes and hypertension, clearly associated with age, besides obesity and smoke, are strongly associated with the need for intensive treatment and a dismal outcome. A weaker immunity of the elderly has been proposed as a possible explanation of this uneven age distribution. Thus, there is concern that children treated for cancer may allso be at risk for an unfavourable course of infection. Along the same line, anecdotal information from Wuhan, China, mentioned a severe course of COVID-19 in a child treated for leukaemia. AIM AND METHODS: We made a flash survey on COVID-19 incidence and severity among children on anticancer treatment. Respondents were asked by email to fill in a short Web-based survey. RESULTS: We received reports from 25 countries, where approximately 10,000 patients at risk are followed up. At the time of the survey, more than 200 of these children were tested, nine of whom were positive for COVID-19. Eight of the nine cases had asymptomatic to mild disease, and one was just diagnosed with COVID-19. We also discuss preventive measures that are in place or should be taken and treatment options in immunocompromised children with COVID-19. CONCLUSION: Thus, even children receiving anticancer chemotherapy may have a mild or asymptomatic course of COVID-19. While we should not underestimate the risk of developing a more severe course of COVID-19 than that observed here, the intensity of preventive measures should not cause delays or obstructions in oncological treatment.

[Different clinical forms of adrenal abscess in two newborns]. / Mellékvesetályog különbözo megjelenési formái két ujszülöttben.

Adrenal abscess is a rare disease in the neonatal period. The classical symptoms are abdominal mass, anaemia and prolonged jaundice which are associated with fever, vomiting and feeding difficulties. The authors present the histories of two mature, male newborns with adrenal hemorrhage, where the size of the masses increased progressively and finally adrenal abscesses were developed. The first case showed the classical symptoms of adrenal abscess, however, the antibiotic treatment led to complete remission of the symptoms and laboratory infectious markers, therefore the baby was discharged. In a few day later he became septic and was admitted again. This time he was operated on and a large abscess was evacuated, which contained about 60 ml of pus. After this intervention multi-organ failure developed, but due to the intensive therapy the baby recovered. In the second newborn the increasing adrenal hemorrhage was accompanied by elevated infectious markers despite of the different antibiotic treatments, however, he showed no clinical signs of infection. Because of the discrepancies between the clinical and laboratory findings and also the imaging studies the possibility of neuroblastoma has also arisen. Urinary vanillylmandelic acid excretion was normal, but elevated neuron-specific enolase levels were measured. Surgical exploration was performed, pus was drained from the mass and anaerobic Bacteroides fragilis was cultured, therefore metronidazole therapy was started. After that the baby fully recovered.