Cost-effectiveness analysis alongside the inter-B-NHL ritux 2010 trial: rituximab in children and adolescents with B cell non-Hodgkin's lymphoma

OBJECTIVES

The randomized controlled trial Inter-B-NHL ritux 2010 showed overall survival (OS) benefit and event-free survival (EFS) benefit with the addition of rituximab to standard Lymphomes Malins B (LMB) chemotherapy in children and adolescents with high-risk, mature B cell non-Hodgkin's lymphoma. Our aim was to assess the cost-effectiveness of rituximab-chemotherapy versus chemotherapy alone in the French setting.

METHODS

We used a decision-analytic semi-Markov model with four health states and 1-month cycles. Resource use was prospectively collected in the Inter-B-NHL ritux 2010 trial (NCT01516580). Transition probabilities were assessed from patient-level data from the trial (n = 328). In the base case analysis, direct medical costs from the French National Insurance Scheme and life-years (LYs) were computed in both arms over a 3-year time horizon. Incremental net monetary benefit and cost-effectiveness acceptability curve were computed through a probabilistic sensitivity analysis. Deterministic sensitivity analysis and several sensitivity analyses on key assumptions were also conducted, including one exploratory analysis with quality-adjusted life years as the health outcome.

RESULTS

OS and EFS benefits shown in the Inter-B-NHL ritux 2010 trial translated into the model by rituximab-chemotherapy being the most effective and also the least expensive strategy over the chemotherapy strategy. The mean difference in LYs between arms was 0.13 [95% CI 0.02; 0.25], and the mean cost difference € - 3 710 [95% CI € - 17,877; € 10,525] in favor of rituximab-chemotherapy group. For a € 50,000 per LY willingness-to-pay threshold, the probability of the rituximab-chemotherapy strategy being cost-effective was 91.1%. All sensitivity analyses confirmed these findings.

CONCLUSION

Adding rituximab to LMB chemotherapy in children and adolescents with high-risk mature B-cell non-Hodgkin's lymphoma is highly cost-effective in France.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01516580.

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.

Effect of rituximab on immune status in children with mature B-cell non-Hodgkin lymphoma: a prespecified secondary analysis of the Inter-B-NHL Ritux 2010 trial

BACKGROUND

Survival of children and adolescents with high-risk, mature B-cell non-Hodgkin lymphoma is improved by the addition of rituximab to chemotherapy. The effect of rituximab on immune reconstitution after therapy has not been well described. Herein, we evaluate the immune effects of the addition of rituximab to intensive chemotherapy, a prespecified secondary aim of the Inter-B-NHL Ritux 2010 trial.

METHODS

The Inter-B-NHL Ritux 2010 trial was an international, open-label, randomised, phase 3 trial in children (age 6 months to 18 years) with high-risk, mature B-cell non-Hodgkin lymphoma, comparing chemotherapy alone or chemotherapy with rituximab. Measures of immune status were completed at baseline, 1 month from the end of treatment, and 1 year from the start of therapy, and yearly thereafter until normalised. For this secondary analysis, we report on the proportions of patients with low lymphocyte counts and immunoglobulin concentrations at these timepoints with total lymphocyte count, B-cell count, and IgG concentration as the main endpoints. Other endpoints of interest included exposure to immunoglobulin replacement therapy and vaccine serologies. The population assessed for immune endpoints was the eligible per-protocol population with at least one immune parameter at one timepoint. Comparisons of immune status were made between the randomised treatment groups. Safety in the post-therapy period was assessed in the population eligible for the immunity study who were followed up at least 3 months after the end of treatment and without cancer-related events. The Inter-B-NHL Ritux 2010 study was registered with ClinicalTrials.gov, NCT01516580; status completed, with analyses of secondary aims ongoing.

FINDINGS

From Dec 19, 2011, to June 13, 2017, 421 patients (344 [82%] boys and 77 [18%] girls; mean age was 8·8 years [SD 4·1]) were enrolled and had immune data at baseline during follow-up, or both. The study population included randomly assigned patients (n=289) and a non-randomised cohort enrolled after the planned interim analysis (n=132). At baseline, 99 (34%) of 290 patients with available data (excluding patients with bone marrow disease with peripheral blast cells) had lymphopenia, and 178 (48%) of 368 had hypogammaglobulinemia. 1 month from the end of therapy, patients who received chemotherapy with rituximab were more likely than those who received chemotherapy alone to have lymphopenia (86 [81%] of 106 vs 53 (60%) of 89, odds ratio [OR] 2·92 [95% CI 1·53-5·57], p=0·0011), B-cell lymphopenia (72 [96%] of 75 vs 36 [64%] of 56, OR 13·33 [3·71-47·84], p<0·0001), and hypogammaglobulinemia (67 [71%] of 95 vs 37 [47%] of 79, OR 2·72 [1·45-5·07], p=0·0017). Differences remained at 1 year for hypogammaglobulinemia only (52 [55%] of 94 vs 16 [25%] of 63, OR 3·64 [1·81-7·31], p=0·0003). Patients in the chemotherapy with rituximab group were more likely than those in the chemotherapy group to receive immunoglobulin replacement (26 [16%] 164 vs nine [7%] of 158, hazard ratio [HR] 2·63 [95% CI 1·23-5·62], p=0·010), mainly due to low immunoglobulin concentration. In the combined treatment groups, including non-randomly assigned patients, the proportion of patients who had loss of protective serologies to a vaccine preventable infection varied from four (9%) of 47 for polio to 21 (42%) of 50 for Streptococcus pneumoniae (pneumococcus). One patient (chemotherapy with rituximab group) had a life-threatening infectious event of polymicrobial bacterial sepsis reported 2 months after the final chemotherapy administration.

INTERPRETATION

Children with high-risk mature B-cell non-Hodgkin lymphoma receiving chemotherapy with rituximab were at risk of prolonged hypogammaglobulinemia, although severe infections were rare. Strategies for immunoglobulin replacement and revaccination are needed.

FUNDING

Clinical Research Hospital Program of the French Ministry of Health, Cancer Research UK, National Institute for Health Research Clinical Research Network in England, Children's Cancer Foundation Hong Kong, US National Cancer Institute, F Hoffmann-La Roche.

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.

Case report: Complete and durable response to larotrectinib (TRK inhibitor) in an infant diagnosed with angiosarcoma harbouring a KHDRBS1-NTRK3 fusion gene

Significant improvements in the survival rates of paediatric cancer have been achieved over the past decade owing to recent advances in therapeutic and diagnostic strategies. However, disease progression and relapse remain a major challenge for the clinical management of paediatric angiosarcoma. Comprehensive genomic profiling of these rare tumours using high-throughput sequencing technologies may improve patient stratification and identify actionable biomarkers for therapeutic intervention. Here, we describe the clinical, histopathological, immunohistochemical and molecular profile of a novel and precision medicine-informed case where a KHDRBS1-NTRK3 fusion determined by next-generation sequencing-based comprehensive genomic profiling led to complete and sustained remission (clinical and radiological response) in an otherwise incurable disease. Our patient represents the first paediatric angiosarcoma harbouring a targetable NTRK3 fusion in the literature and demonstrates the first example of targeting this alteration in angiosarcoma using larotrectinib, an NTRK inhibitor. Clinical and radiological remission was achieved in under two months of therapy, and the patient is currently in complete remission, 4 month after stopping larotrectinib therapy, which was given over 17 months with only mild side effects reported. Therefore, this remarkable case exemplifies the true essence of precision-based care by incorporating conventional pathology with the why, when, and how to test for rare oncogenic drivers and agnostic biomarkers in paediatric angiosarcoma.

Osteosarcoma and causes of death: A report of 1520 deceased patients from the Cooperative Osteosarcoma Study Group (COSS)

PURPOSE

Most aspects of osteosarcoma have been addressed in detail, but there is no comprehensive analysis of deceased patients and causes of death.

METHODS

The database of the Cooperative Osteosarcoma Study Group COSS (1980-03/31/2021; 4475 registered high-grade central osteosarcoma patients) was searched deaths from any cause. Affected patients were analyzed for demographic and baseline variables and disease-status at the time of demise. Deaths from causes other than osteosarcoma were analyzed in detail.

RESULTS

A total of 1520 deceased patients were identified (median age (range) at osteosarcoma diagnosis 16 (2-78) years; 908 (59.7%) male, 612 (40.3%) female; primary tumor: extremities 1263 (83.1%), trunk 208 (13.7%), craniofacial 47 (3.1%) (site unknown 2); metastases at registration: absent 1.051 (69.1%), present 466 (30.7%) (3 no data). The median time from diagnosis to death was 2.22 (0.08-32.02) years. 1286 (84.6%) patients succumbed to osteosarcoma (370 without achieving complete remission, 488 first, 428 more than one recurrences), 146 (9.6%) to other, 88 (5.8%) to unknown causes. Chemotherapy-related infections (40), secondary malignancies (39), and perioperative complications (19) were among the most frequent potentially treatment-related causes, and high-dose methotrexate (19), doxorubicin (17), and ifosfamide (15) were the drugs most commonly held responsible. Patients with unknown causes of death had an unusually long median follow-up.

CONCLUSION

The major cause of death of patients after osteosarcoma is this malignancy, mostly from one of its multiple relapses. However, almost 10% of fatalities are due to other documented causes. Some of these deaths may be preventable with the knowledge gained from comprehensive analyses such as this.

The Global Retinoblastoma Outcome Study: a prospective, cluster-based analysis of 4064 patients from 149 countries

Background

Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival.

Methods

We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models.

Findings

The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope).

Interpretation

This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.

Funding

Queen Elizabeth Diamond Jubilee Trust.

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.

In Situ Analysis of mTORC1/C2 and Metabolism-Related Proteins in Pediatric Osteosarcoma

Activation of the mTOR pathway has been observed in osteosarcoma, however the inhibition of mammalian target of rapamycin (mTOR) complex 1 has had limited results in osteosarcoma treatment. Certain metabolic pathways can be altered by mTOR activation, which can affect survival. Our aim was to characterize the mTOR profile and certain metabolic alterations in pediatric osteosarcoma to determine the interactions between the mTOR pathway and metabolic pathways. We performed immunohistochemistry on 28 samples to analyze the expression of mTOR complexes such as phospho-mTOR (pmTOR), phosphorylated ribosomal S6 (pS6), and rapamycin-insensitive companion of mTOR (rictor). To characterize metabolic pathway markers, we investigated the expression of phosphofructokinase (PFK), lactate dehydrogenase-A (LDHA), β-F1-ATPase (ATPB), glucose-6-phosphate dehydrogenase (G6PDH), glutaminase (GLS), fatty acid synthetase (FASN), and carnitin-O-palmitoyltransferase-1 (CPT1A). In total, 61% of the cases showed low mTOR activity, but higher pmTOR expression was associated with poor histological response to chemotherapy and osteoblastic subtype. Rictor expression was higher in metastatic disease and older age at the time of diagnosis. Our findings suggest the importance of the Warburg-effect, pentose-phosphate pathway, glutamine demand, and fatty-acid beta oxidation in osteosarcoma cells. mTOR activation is linked to several metabolic pathways. We suggest performing a detailed investigation of the mTOR profile before considering mTORC1 inhibitor therapy. Our findings highlight that targeting certain metabolic pathways could be an alternative therapeutic approach.

miRNA Profiling of Hungarian Regressive Wilms' Tumor Formalin-Fixed Paraffin-Embedded (FFPE) Samples by Quantitative Real-Time Polymerase Chain Reaction (RT-PCR)

BACKGROUND Wilms' tumor is a common renal malignancy of early childhood with a generally favorable prognosis depending upon histological subtype. It is becoming increasingly clear that differences in miRNA (microRNA) expression signature represent important clues helping us predict a tumor's response to chemotherapy. In our study, we aimed to reveal miRNAs deregulated in regressive Wilms' tumors from FFPE (formalin-fixed, paraffin-embedded) samples, also showing whether such samples are reliable miRNA sources in Wilms' tumor. MATERIAL AND METHODS Samples from 8 Hungarian patients (3 males, 5 females, aged 1 to 7 years) were analyzed by qRT-PCR (quantitative real-time PCR). A PCR array was used in a pilot experiment, and selected miRNAs (miR-128-3p, miR-184, miR-194-5p, miR-203a) were studied in the rest of the samples using individual primers. RESULTS miR-194-5p was underexpressed in all tumor samples. miR-184 and miR-203a were underexpressed in 7 cases, the exception being a case with a high ratio of necrotic blastemal tissue. Results obtained with miR-128-3p are difficult to interpret due to varying directions of expression changes. CONCLUSIONS We conclude that a downregulation of miR-184, miR-194-5p, and miR-203a expression is observed in both regressive and blastemal tumors, but larger-scale studies are needed to confirm whether the degree of their underexpression correlates with the number of blastemal elements in a sample. In most of our FFPE samples aged up to 9 years, RNA extraction provided miRNA with quantity and quality sufficient for qRT-PCR-based analysis, emphasizing the relevance of pathological archives as miRNA sources in future studies.

Diagnosis and treatment of paediatric multisystem inflammatory syndrome

Összefoglaló. A SARS-CoV-2-fertőzés ritka gyermekkori szövődménye a sokszervi gyulladás, angol terminológiával paediatric inflammatory multisystem syndrome (PIMS). Két vagy több szerv érintettségével járó, súlyos tünetekkel induló betegségről van szó, amelynek tünetei átfedést mutatnak a Kawasaki-betegséggel, a toxikus sokk szindrómával és a makrofágaktivációs szindrómával. A PIMS-betegek intenzív terápiás osztályon vagy intenzív terápiás háttérrel rendelkező intézményben kezelendők, ahol biztosítottak a kardiológiai ellátás feltételei is. A szükséges immunterápia a klinikai prezentációtól függ. A jelen közleményben a szerzők a releváns nemzetközi irodalom áttekintését követően ajánlást tesznek a PIMS diagnosztikai és terápiás algoritmusára. Orv Hetil. 2021; 162(17): 652-667. Summary. Pediatric inflammatory multisystem syndrome (PIMS) is a rare complication of SARS-CoV-2 infection in children. PIMS is a severe condition, involving two or more organ systems. The symptoms overlap with Kawasaki disease, toxic shock syndrome and macrophage activation syndrome. PIMS patients should be treated in an intensive care unit or in an institution with an intensive care background, where cardiological care is also provided. The required specific immunotherapy depends on the clinical presentation. In this paper, after reviewing the relevant international literature, the authors make a recommendation for the diagnostic and therapeutic algorithm for PIMS. Orv Hetil. 2021; 162(17): 652-667.

Prognostic Factors in Childhood Anaplastic Large Cell Lymphoma: Long Term Results of the International ALCL99 Trial

With the aim of describing the long-term follow-up and to define the prognostic role of the clinical/pathological/molecular characteristics at diagnosis for childhood, adolescent and young adults affected by anaplastic large cell lymphoma (ALCL), we analyzed 420 patients aged up to 22 years homogeneously treated within the international ALCL99 trial. The 10-year progression free survival (PFS) was 70% and overall survival was 90%, rare late relapses occurred but no secondary malignancies were reported. Among clinical/pathological characteristics, only patients presenting a small cell/lymphohistiocytic (SC/LH) pattern were independently associated with risk of failure (hazard ratio = 2.49). Analysis of minimal disseminated disease (MDD), available for 162 patients, showed that both SC/LH pattern (hazard ratio = 2.4) and MDD positivity (hazard ratio = 2.15) were significantly associated with risk of failure in multivariate analysis. Considering MDD and SC/LH results, patients were separated into three biological/pathological (bp) risk groups: a high-risk group (bpHR) including MDD-positive patients with SC/LH pattern; a low-risk group (bpLR) including MDD-negative patients without SC/LH pattern; and an intermediate-risk group (bpIR) including remaining patients. The 10-year PFS was 40%, 75% and 86% for bpHR, bpIR and bpLR, respectively (p < 0.0001). These results should be considered in the design of future ALCL trials to tailor individual treatments.

Travel burden and clinical presentation of retinoblastoma: analysis of 1024 patients from 43 African countries and 518 patients from 40 European countries

BACKGROUND

The travel distance from home to a treatment centre, which may impact the stage at diagnosis, has not been investigated for retinoblastoma, the most common childhood eye cancer. We aimed to investigate the travel burden and its impact on clinical presentation in a large sample of patients with retinoblastoma from Africa and Europe.

METHODS

A cross-sectional analysis including 518 treatment-naïve patients with retinoblastoma residing in 40 European countries and 1024 treatment-naïve patients with retinoblastoma residing in 43 African countries.

RESULTS

Capture rate was 42.2% of expected patients from Africa and 108.8% from Europe. African patients were older (95% CI -12.4 to -5.4, p<0.001), had fewer cases of familial retinoblastoma (95% CI 2.0 to 5.3, p<0.001) and presented with more advanced disease (95% CI 6.0 to 9.8, p<0.001); 43.4% and 15.4% of Africans had extraocular retinoblastoma and distant metastasis at the time of diagnosis, respectively, compared to 2.9% and 1.0% of the Europeans. To reach a retinoblastoma centre, European patients travelled 421.8 km compared to Africans who travelled 185.7 km (p<0.001). On regression analysis, lower-national income level, African residence and older age (p<0.001), but not travel distance (p=0.19), were risk factors for advanced disease.

CONCLUSIONS

Fewer than half the expected number of patients with retinoblastoma presented to African referral centres in 2017, suggesting poor awareness or other barriers to access. Despite the relatively shorter distance travelled by African patients, they presented with later-stage disease. Health education about retinoblastoma is needed for carers and health workers in Africa in order to increase capture rate and promote early referral.

Characterization of mTOR Activity and Metabolic Profile in Pediatric Rhabdomyosarcoma

mTOR activation has been observed in rhabdomyosarcoma (RMS); however, mTOR complex (mTORC) 1 inhibition has had limited success thus far. mTOR activation alters the metabolic pathways, which is linked to survival and metastasis. These pathways have not been thoroughly analyzed in RMSs. We performed immunohistochemistry on 65 samples to analyze the expression of mTOR complexes (pmTOR, pS6, Rictor), and several metabolic enzymes (phosphofructokinase, lactate dehydrogenase-A, β-F1-ATPase, glucose-6-phosphate dehydrogenase, glutaminase). RICTOR amplification, as a potential mechanism of Rictor overexpression, was analyzed by FISH and digital droplet PCR. In total, 64% of the studied primary samples showed mTOR activity with an mTORC2 dominance (82%). Chemotherapy did not cause any relevant change in mTOR activity. Elevated mTOR activity was associated with a worse prognosis in relapsed cases. RICTOR amplification was not confirmed in any of the cases. Our findings suggest the importance of the Warburg effect and the pentose-phosphate pathway beside a glutamine demand in RMS cells. The expression pattern of the studied mTOR markers can explain the inefficacy of mTORC1 inhibitor therapy. Therefore, we suggest performing a detailed investigation of the mTOR profile before administering mTORC1 inhibitor therapy. Furthermore, our findings highlight that targeting the metabolic plasticity could be an alternative therapeutic approach.

Global Retinoblastoma Presentation and Analysis by National Income Level

Importance

Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale.

Objectives

To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis.

Design, Setting, and Participants

A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017.

Main Outcomes and Measures

Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis.

Results

The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]).

Conclusions and Relevance

This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs.

Quantitative RT-PCR-based miRNA profiling of blastemal Wilms' tumors from formalin-fixed paraffin-embedded samples

Blastemal Wilms' tumors are associated with poor chemo-responsiveness and an adverse prognosis. Our aim was to contribute to the miRNA profiling of the disease, while demonstrating the value of archived formalin-fixed, paraffin-embedded (FFPE) samples as miRNA sources. MiRNA was extracted from tumor and normal tissues of 8 patients diagnosed with blastemal Wilms' tumor in Hungary. A quantitative real-time PCR-based protocol was used to identify miRNAs of interest and study the expression of selected miRNAs in all samples. Profiling of miRNA expression from FFPE samples turned out to be cost-effective in Wilms' tumor, as most miRNAs (including miRNA-194-5p, which was studied in all patients) showed expression alterations similar to the ones reported in the literature. MiR-184 expression was found to be lower than in previous studies, while the downregulation of miR-203a is a novel finding. MiR-184 may be downregulated in a subset of blastemal and other Wilms' tumors. A loss of miR-203a may or may not be specific to blastemal cells, but available evidence hints at its importance in the pathogenesis of Wilms' tumor. It should be considered for inclusion in future studies of miRNA expression.

[Treatment results of pediatric soft tissue sarcomas at the 2nd Department of Pediatrics, Semmelweis University]

Malignant tumors found in children are different from the ones that occur in adults. Compared to the malignancies in adults, the histological entities in pediatric patients are different and survival rates are higher among the children. Though pediatric soft tissue sarcomas are less common than leukemia and central nervous system malignancies, recognition of them is necessary to start the therapy as soon as possible. The delay of an appropriate treatment - chemotherapy, radiotherapy, surgery, in some cases targeted therapy - is unfavorable because somatic damages and functional loss can occur. In our study at the oncology department of the 2nd Department of Pediatrics of Semmelweis University, we collected and analyzed the data of 90 children who were diagnosed with soft tissue sarcomas between January of 2000 and November of 2016. Our results correlate with the data collected worldwide.

The Presence of ALK Alterations and Clinical Relevance of Crizotinib Treatment in Pediatric Solid Tumors

Soft tissue sarcomas (STS) and neuroblastomas (NBL), are childhood malignancies still associated with poor prognoses despite the overall improvement in childhood tumor survival of the past decades. Anaplastic lymphoma kinase (ALK) inhibition is promising new strategy to improve the outcome of these pediatric tumors. Eighteen histologic samples of pediatric STS and 19 NBL patients were analyzed for ALK abnormalities using fluorescent in situ hybridization (FISH) with break-apart probes and immunohistochemistry (IHC). ALK alterations were presented in 20 of the 37 sections. The presence of ALK alteration in NBL samples were detected using IHC in 84,2% of all cases compared to 21,1% FISH positivity. In STS cases the results were less different (IHC 16,7% vs FISH 22,2%). The difference can be explained by the different type of molecular alterations. FISH method detected translocation and amplification, but not the point mutation of ALK gene. IHC confirmed the diagnosis by detecting the expression of ALK protein.After ALK positivity was proven, the effectiveness and safety of the crizotinib therapy was examined in 4 patients (1 alveolar rhabdomyosarcoma (RMA), 1 embryonal rhabdomyosarcoma (RME), 1 inflammatory myofibroblastic tumor (IMT), 1 NBL). We observed continuous remission of the IMT patient, all other cases the inhibitor treatment was not curative.Our findings underline the importance of screening the ALK status parallel with both IHC and FISH. Crizotinib treatment had a long-term effect in ALK positive IMT patients, however itwas only temporary efficient in relapsed, progressive STS and NBL.

Effective BRAF inhibitor vemurafenib therapy in a 2-year-old patient with sequentially diagnosed Langerhans cell histiocytosis and Erdheim-Chester disease

Erdheim-Chester disease (ECD) is a rare histiocytic disorder, characterized by the xanthomatous infiltration of tissues by CD68-positive and CD1a-/CD100-negative foamy histiocytes. In childhood, ECD is exceptionally rare, and only a dozen cases have been published so far. The cooccurence of Langerhans cell histiocytosis (LCH) and ECD is even rarer. Here, we report a 2-year-old boy, the youngest patient in the literature so far, who was diagnosed with concomitant BRAF mutation-positive LCH and ECD. In his case, conventional LCH treatment proved to be ineffective, but he is the youngest patient who was successfully treated with the BRAF inhibitor vemurafenib.

Primary alveolar rhabdomyosarcoma of the bone: two cases and review of the literature

BACKGROUND

Rhabdomyosarcoma (RMS) is a malignant tumor of mesenchymal origin and comprises the largest category of soft-tissue sarcomas both in children and adolescents. From a pediatric oncology point of view, RMS has traditionally been classified into alveolar (ARMS) and embryonal (ERMS) subtypes. The anatomical localization of the tumor may vary, but commonly involve the head/neck regions, male and female urogenital tract or the trunk and extremities.

CASE PRESENTATION

Here, we report two challenging cases involving 17- and 9-years-olds males where diffuse and multiplex bone lesions suggested either a hematological disease or a primary bone tumor (mesenchymal chondrosarcoma). Biopsies, proved a massive infiltration of the bone marrow cavity with rhabdomyosarcoma. In both cases, the ARMS subtype was confirmed using FOXO1 break-apart probes (FISH). Radiological examination could not identify primary soft tissue component in any localization at the time of diagnosis in either cases.

CONCLUSIONS

Primary alveolar rhabdomyosarcoma of the bone as a subtype of ARMS, seems to be a distinct clinico-pathological entity with challenging diagnostic difficulties and different, yet better, biological behavior in comparison to soft tissue ARMS. However, it is difficult to be characterized or predict its prognosis and long-term survival as only sporadic cases (four) were reported so far.

Non-anaplastic peripheral T cell lymphoma in children and adolescents-an international review of 143 cases

Peripheral T cell lymphomas (PTCL) are rare in children and adolescents, and data about outcome and treatment results are scarce. The present study is a joint, international, retrospective analysis of 143 reported cases of non-anaplastic PTCL in patients <19 years of age, with a focus on treatment and outcome features. One hundred forty-three patients, between 0.3 and 18.7 years old, diagnosed between 2000 and 2015 were included in the study. PTCL not otherwise specified was the largest subgroup, followed by extranodal NK/T cell lymphoma, hepatosplenic T cell lymphoma (HS TCL), and subcutaneous panniculitis-like T cell lymphoma (SP TCL). Probability of overall survival (pOS) at 5 years for the whole group was 0.56 ± 0.05, and probability of event-free survival was (pEFS) 0.45 ± 0.05. Patients with SP TCL had a good outcome with 5-year pOS of 0.78 ± 0.1 while patients with HS TCL were reported with 5-year pOS of only 0.13 ± 0.12. Twenty-five percent of the patients were reported to have a pre-existing condition, and this group had a dismal outcome with 5-year pOS of 0.29 ± 0.09. The distribution of non-anaplastic PTCL subtypes in pediatric and adolescent patients differs from what is reported in adult patients. Overall outcome depends on the subtype with some doing better than others. Pre-existing conditions are frequent and associated with poor outcomes. There is a clear need for subtype-based treatment recommendations for children and adolescents with PTCL.

CD8+/FOXP3+-ratio in osteosarcoma microenvironment separates survivors from non-survivors: a multicenter validated retrospective study

Osteosarcoma is the most common primary bone tumor characterized by juvenile onset, tumor heterogeneity, and early pulmonary metastasis. Therapeutic improvement stagnates since more than two decades. Unlike major malignancies, biomarkers as prognostic factors at time of diagnosis are missing. Disease rareness hampers study recruitment of patient numbers sufficient to outweigh tumor heterogeneity. Here, we analyzed in a multicenter cohort the osteosarcoma microenvironment to reduce effects of tumor cell heterogeneity. We hypothesized that quantitative ratios of intratumoral CD8⁺T-cells to FOXP3⁺T-cells (CD8⁺/FOXP3⁺-ratios) provide strong prognostic information when analyzed by whole-slide imaging in diagnostic biopsies. We followed recommendations-for-tumor-marker-prognostic-studies (REMARK). From 150 included cases, patients with complete treatment were identified and assigned to the discovery (diagnosis before 2004) or the validation cohort (diagnosis 2004-2012). Highly standardized immunohistochemistry of CD8⁺ and FOXP3⁺, which was validated by methylation-specific gene analysis, was performed followed by whole-slide analysis and clinical outcome correlations. We observed improved estimated survival in patients with CD8⁺/FOXP3⁺-ratios above the median (3.08) compared to patients with lower CD8⁺/FOXP3⁺-ratios (p = 0.000001). No patients with a CD8⁺/FOXP3⁺-ratio above the third quartile died within the observation period (median follow-up 69 mo). Multivariate analysis demonstrated independence from current prognostic factors including metastasis and response to neoadjuvant chemotherapy. Data from an independent validation cohort confirmed improved survival (p = 0.001) in patients with CD8⁺/FOXP3⁺-ratios above 3.08. Multivariate analysis proofed that this observation was also independent from prognostic factors at diagnosis within the validation cohort. Intratumoral CD8⁺/FOXP3⁺-ratio in pretreatment biopsies separates patients with prolonged survival from non-survivors in osteosarcoma.

[Diagnosis and treatment of childhood soft tissue sarcomas]

Malignant tumors of mesenchymal origin are called sarcomas. Mesenchymal cells normally mature into skeletal muscle, smooth muscle, fat, fibrous tissue, bone and cartilage. Rhabdomyosarcoma (RMS) arises from immature mesenchymal cells that are committed to skeletal muscle lineage. However, it can also arise in tissues in which striated muscle is normally not found (such as the urinary tract). Undifferentiated sarcomas cannot be ascribed to any specific lineage. Treatment results improved significantly in the last decade by combined treatment (chemotherapy, surgery, irradiation, in some cases targeted therapy). Good treatment results can be achieved in pediatric oncology centers by early diagnosis and adequate treatment according to international treatment protocols.

Characteristic mTOR activity in Hodgkin-lymphomas offers a potential therapeutic target in high risk disease--a combined tissue microarray, in vitro and in vivo study

Background

Targeting signaling pathways is an attractive approach in many malignancies. The PI3K/Akt/mTOR pathway is activated in a number of human neoplasms, accompanied by lower overall and/or disease free survival. mTOR kinase inhibitors have been introduced in the therapy of renal cell carcinoma and mantle cell lymphoma, and several trials are currently underway. However, the pathological characterization of mTOR activity in lymphomas is still incomplete.

Methods

mTOR activity and the elements of mTOR complexes were investigated by immunohistochemistry on tissue microarrays representing different human non-Hodgkin-lymphomas (81 cases) and Hodgkin-lymphomas (87 cases). The expression of phospho-mTOR, phospho-4EBP1, phospho-p70S6K, phospho-S6, Rictor, Raptor and Bcl-2, Bcl-xL, Survivin and NF-kappaB-p50 were evaluated, and mTOR activity was statistically analyzed along with 5-year survival data. The in vitro and in vivo effect of the mTOR inhibitor rapamycin was also examined in human Hodgkin-lymphoma cell lines.

Results

The majority (>50%) of mantle cell lymphoma, Burkitt lymphoma, diffuse large B-cell lymphoma, anaplastic large-cell lymphoma and Hodgkin-lymphoma cases showed higher mTOR activity compared to normal lymphoid tissues. Hodgkin-lymphoma was characterized by high mTOR activity in 93% of the cases, and Bcl-xL and NF-kappaB expression correlated with this mTOR activity. High mTOR activity was observed in the case of both favorable and unfavorable clinical response. Low mTOR activity was accompanied by complete remission and at least 5-year disease free survival in Hodgkin-lymphoma patients. However, statistical analysis did not identify correlation beetween mTOR activity and different clinical data of HL patients, such as survival. We also found that Rictor (mTORC2) was not overexpressed in Hodgkin-lymphoma biopsies and cell lines. Rapamycin inhibited proliferation and induced apoptosis in Hodgkin-lymphoma cells both in vitro and in vivo, moreover, it increased the apoptotic effect of chemotherapeutic agents.

Conclusions

Targeting mTOR activity may be a potential therapeutic tool in lymphomas. The presence of mTOR activity probably indicates that the inclusion of mTOR inhibition in the therapy of Hodgkin-lymphomas may be feasible and beneficial, especially when standard protocols are ineffective, and it may also allow dose reduction in order to decrease late treatment toxicity. Most likely, the combination of mTOR inhibitors with other agents will offer the highest efficiency for achieving the best clinical response.

Mammalian target of rapamycin (mTOR) activity dependent phospho-protein expression in childhood acute lymphoblastic leukemia (ALL)

Modern treatment strategies have improved the prognosis of childhood ALL; however, treatment still fails in 25–30% of patients. Further improvement of treatment may depend on the development of targeted therapies. mTOR kinase, a central mediator of several signaling pathways, has recently attracted remarkable attention as a potential target in pediatric ALL. However, limited data exists about the activity of mTOR. In the present study, the amount of mTOR activity dependent phospho-proteins was characterized by ELISA in human leukemia cell lines and in lymphoblasts from childhood ALL patients (n = 49). Expression was measured before and during chemotherapy and at relapses. Leukemia cell lines exhibited increased mTOR activity, indicated by phospho-S6 ribosomal protein (p-S6) and phosphorylated eukaryotic initiation factor 4E binding protein (p-4EBP1). Elevated p-4EBP1 protein levels were detected in ALL samples at diagnosis; efficacy of chemotherapy was followed by the decrease of mTOR activity dependent protein phosphorylation. Optical density (OD) for p-4EBP1 (ELISA) was significantly higher in patients with poor prognosis at diagnosis, and in the samples of relapsed patients. Our results suggest that measuring mTOR activity related phospho-proteins such as p-4EBP1 by ELISA may help to identify patients with poor prognosis before treatment, and to detect early relapses. Determining mTOR activity in leukemic cells may also be a useful tool for selecting patients who may benefit from future mTOR inhibitor treatments.

Six cases of rare gene amplifications and multiple copy of fusion gene in childhood acute lymphoblastic leukemia

Cytogenetic aberrations are very important factors in risk assessment of childhood hematological malignancies. We report six childhood acute lymphoid leukemia (ALL) cases with rare cytogenetic aberrations: five with RUNX1, ABL1 or MLL proto-oncogene amplification and one case of multiple copies of ETV6/RUNX1 fusion genes. The simultaneous presence of two adverse genetic aberrations is of special interest: ETV6-RUNX1 fusion gene is associated with good prognosis and intrachromosomal amplification of the homologue RUNX1 gene is associated with poor prognosis. We also report a patient with MLL amplification, a unique finding in childhood T-ALL. Report of these subtle rearrangements contributes to our understanding of diagnostic and prognostic significance of these rare cytogenetic abnormalities.

[Pharmacokinetic analysis of high-dose methotrexate treatments in children with hematologic malignancies]

Monitoring the pharmacokinetic parameters of different anticancer drugs is necessary because they might have several side effects.

AIM

Pharmacokinetic and toxicity evaluation of high-dose methotrexate treatments in children with acute lymphoblastic leukemia.

PATIENTS AND METHODS

43 children (28 boys, 15 girls, mean age: 7.03 years) in 147 cases were treated with 5 g/m2/24h MTX according to ALL-BFM 1995 and 2002 protocols. Methotrexate and 7-hydroxi-methotrexate levels were measured with high pressure liquid chromatography at 24, 36, 48 hours. Authors registered the development of hepatotoxicity, nephrotoxicity, grade III/IV oral mucositis.

RESULTS

Therapeutic methotrexate serum concentrations (30-100µmol/l) were achieved in 72.5% of the cases. Repeated treatments resulted similar serum levels. Hepatotoxicity and hypoproteinemia occurred in 17% and in 48.9% of the cases. There was significant correlation between serum 7-hydroxi-methotrexate and creatinine levels (p<0.05).

CONCLUSION

5 g/m2 methotrexate resulted reliable therapeutic serum levels with mild and reversible toxicity. 7-hydroxi-methotexate measurements might be more useful than methotrexate levels to detect toxicity.

[Hodgkin's lymphoma in adolescents: where to treat it--in an adult or pediatric institution?]

Adolescent patients with Hodgkin's lymphoma (HL) are treated either in pediatric, or in adult oncological wards.

AIM

The aim of our work was to compare the treatment modalities and the survival rates in adolescents with HL treated in adult (A) or pediatric (P) institutes.

METHODS

From January 1990 to December 2004, 138 patients (14-21 years) with HL were treated in two adult institutes (A) and 107 in the 10 centres of the Hungarian Pediatric Oncology Network (P).

RESULTS

Male:female ratio was 1:1.15 (A) and 1:1.38 (P). The mean age was 18.6 (A) and 15.7 (P) years. There was no difference between the distribution of the stages in the two patient groups. The distribution of histological subtypes (A and P): nodular sclerosing 47% and 59%, mixed cellularity 45% and 25%, lymphocyte rich 1.5% and 10%, lymphocyte depleted 4% and 1%, nodular lymphocyte predominant 1.5% and 3% and unknown 1% and 2%. The majority of the patients were treated with ABVD (A) and OPPA/OEPA +/- COPP (P). One hundred and fifteen (A) and 97 (P) adolescents received irradiation therapy. 80% (A) and 91% (A) of the patients got radiotherapy. In group A 14%, in group P 13% of the patients had relapse. In group A 16 patients died and in group P 7. There was no significant difference in the overall survival (OS) rates at 5 and 10 years in the two patient groups. The event-free survival (EFS) was 76.5 +/- 4% and 72.5 +/- 4% at 5 and 10 years in group A, and 85.3 +/- 4% at both times in group P ( p = 0.0452).

CONCLUSION

Survival rates in HL are quite high, 80-90% of the patients can be cured. Event-free survival was higher in pediatric than in adult institutes. In case of patients younger than 18 years, the survival rates were much better in pediatric institutes, so these patients should be treated in pediatric institutes or with protocols used by the pediatricians.

[Lymphomas in adolescents: are childhood lymphoma therapy protocols suitable for this patient group?]

The centres of the Hungarian Paediatric Oncology Network annually take care of 250-300 new patients with childhood cancer, every tenth of them suffering from lymphoma. The aim of our work was to analyse the data of the adolescents (14-19 years) with Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), comparing their survival rates with younger patients under fourteen and with the international data. From January 1990 to December 2004 there were 281 children diagnosed with HL and 230 with NHL. Among the HL patients 107, while among the NHL patients 51 were older than 14 years old. In the group of HL the distribution of patients according to the stage was similar in younger and older patients. In the NHL group 55% of the children younger than 14, and 72% of the patients older than 14 years old had advanced stage disease (stage III or IV). In both groups the patients received chemotherapy according to the current paediatric protocols. The overall survival (OS) of the HL patients younger than 14 was 92.5+/-2% at 5 years and 90.3+/-2% at 10 years, and for the adolescents 93.4+/-2% and 90.7+/-3% at 5 and 10 years (n.s.). The OS of the younger children in the NHL group was 78.2+/-3% at 5 and 10 years, and 77.9+/-6% for the adolescents (n.s.). As a conclusion, survival rates of the adolescents do not differ significantly from the parameters of the patients under fourteen, so the therapy protocols used for childhood lymphomas are suitable for the treatment of the lymphomas appearing at the age of 14-19 years.

[Cytogenetic and FISH findings are complementary in childhood ALL]

Primary genetic abnormalities of leukemia cells have important prognostic significance in childhood acute leukemia. In the last two years 30 newly diagnosed or recurrent childhood ALL bone marrow samples were analyzed for chromosomal abnormalities with conventional G-banding and interphase-fluorescence in situ hybridization (I-FISH) using probes to detect BCR/ABL fusions, cryptic TEL/AML1 and MLL rearrangements and p16(9p21) tumor suppressor gene deletions. G-banded karyotype analysis found clonal chromosomal aberrations in 50% of cases. With the use of complementary I-FISH techniques, ALL-specific structural and numerical changes could be identified in 70% of the patients. Nine cases (30%) had subtle chromosomal aberrations with prognostic importance that had not been detected in G-banded analysis. Conventional G-banding yielded additional information (rare and complex structural aberrations) in 19% of patients. The most common aberration (30%) was AML1 copy number increase present in G-banded hyperdiploid karyotype as a chromosome 21 tetrasomy in the majority of cases; one case displayed 5-6 copies and in another case amplification of AML1 gene on der(21) was combined with TEL/AML1 fusion of the homologue AML1 gene and deletion of the remaining TEL allele. High hiperdiploidy was detected in 6 cases, in one patient with normal G-banding karyotype. TEL/AML1 fusion signals were identified in four patients. Deletion of p16 locus was found in eight cases (23%), of which only two had cytogenetically visible rearrangements. G-banding in combination with I-FISH has produced major improvements in the sensitivity and accuracy of cytogenetic analysis of ALL patients and this method helps to achieve a more precise identification of different risk categories in order to choose the optimal treatment.

[Intrachromosomal amplification of AML1 gene in childhood acute lymphoblastic leukemia]

The introduction of routine molecular cytogenetic assays enabled us to reveal hitherto unknown genetic disorders of childhood acute leukemias. Of special interest is the recognition of those rare cytogenetic mutations of negative prognostic value, which are associated with well-known markers of good prognosis. In our present study we review a novel cytogenetic mutation typical for childhood B-cell ALL, the intrachromosomal amplification of chromosome 21, which requires high-risk therapy irrespective of other risk factors, and which is associated with a cryptic 12;21 translocation of good prognostic value.

Treatment of pediatric non-Hodgkin lymphoma in Hungary: 15 years experience with NHL-BFM 90 and 95 protocols

Retrospective analysis was performed to assess the survival-rates of children with non-Hodgkin lymphoma (NHL), treated according to the NHL-BFM (Berlin-Frankfurt-Münster)-90 and -95 protocols between 1990 and 2004 in Hungary, and to compare our data with the international results. Ninety-one patients had non-B-NHL, 108 B-NHL, and 31 ALCL. Complete remission rate was 89%, while 12% relapsed later. The 5-year-overall-survival was 78% and the event-free survival was 75%. These results are lower than those reported by the BFM study group, but comparable from other European centers. In the last 5 years, the results showed 10% improvement and death during induction was reduced from 10 to 3%.

[The function of the immune system after the treatment of pediatric malignant diseases]

INTRODUCTION

Currently, malignancies in childhood can be cured in 70 percent of the cases. However, the intensive cytostatic therapy may lead to late side effects influencing quality of life.

AIM OF THE STUDY

Analysis of the reconvalescence of the immune functions after completion of therapy for malignancies in children.

PATIENTS

88 long-term survivors (51 boys, 37 girls) were investigated (43 acute lymphoid leukemia, 15 lymphoma, 20 bone tumors, 10 other solid tumors). Mean age at the time of diagnosis was 7.8 years (1 mo-17.7 years).

METHODS

The following parameters were investigated: serum immunoglobulin levels after completion of the chemotherapy and in the next 4 years thereafter, lymphocyte subpopulations in the peripheral blood by flow-cytometry and cellular immunity by in vitro tests (natural killer activity, antibody-dependent cellular cytotoxicity, mitogen-induced T- and B-cell blastic transformations).

RESULTS

Lower serum immunoglobulin (IgG) levels could be detected in patients with leukemia after completion of the chemotherapy (8.8 +/- 3.2 g/l). One year thereafter serum IgG levels increased significantly (10.1 +/- 2.9 g/l) (p<0.05). In patients with solid tumors the serum IgG levels were in the normal range at the end of the chemotherapy (12.1 +/- 4.3 g/l). At a mean of 1.3 years after the end of chemotherapy NK activity decreased in 7/43 (16.3%) leukemia patients, and in 3/45 (6.7%) solid tumor patients, ADCC decreased in 8/43 (18.6%) and 3/45 (6.7%), respectively (p<0.05 leukemia vs. solid tumor). At a mean of 15 months after the end of the therapy B-cell blastic transformation was decreased in 3/43 (7%) leukemia patients and in 4/45 (8.9%) solid tumor patients. At the same time point T-cell blastic transformation was altered in 5/43 (11.6%) and in 4/45 (8.9%) cases, respectively.

CONCLUSION

Cytotoxic therapies lead to severe, long-term depression of the immune system. At the end of the chemotherapy this effect is more pronounced in leukemia patients. Years (1.5-3) after completion of the therapy in a significant proportion of the patients some in vitro parameters of the immune system are yet altered, so careful monitoring of this patient population is mandatory.

Hungarian experience with Langerhans cell histiocytosis in childhood

The Langerhans cell histiocytosis (LCH) in children is relatively rare and the long-term analysis of therapy results has not been done yet in Hungary. The aim of this study was to investigate the incidence, clinical features, prognostic risk factors, and treatment results of children's LCH in Hungary in a 20-year period. Children less than 18 years of age with newly diagnosed LCH in Hungary were entered in this study. Clinical data of all children with LCH were reported to the National Childhood Cancer Registry in Hungary from 1981 to 2000. The clinical files were collected and abstracted for information regarding age at diagnosis, gender, disease characteristics, treatment, and outcome of treatment. Median follow-up duration of surviving patients is 10.98 years. Between January 1981 and December 2000, 111 children under 18 years of age were newly diagnosed with LCH in Hungary. The annual incidence of LCH in children younger than 18 years of age was 2.24/million children. The male-female ratio was 1.36:1; the mean age was 4 years 11 months. Thirty-eight children had localized disease and in 73 cases systemic dissemination was found already at the time of diagnosis. Twenty-two patients were treated only by local surgery, 7 by surgery with local irradiation, and 5 children got only local irradiation. In 2 cases remission was achieved with local steroid administration. Seventy-five patients received chemotherapy. In the 20 years of the study 14 children died, 9 due to the progression of the disease. Sixteen patients had relapse with a mean of 2.16 +/- 1.29 years after the first diagnosis. Three patients with relapse got chemotherapy generally used in lymphoma and remission was achieved. The overall survival of all patients (n = 111) was 88.3 +/- 3.1% at 5 years and 87.3 +/- 3.2% at 10 and 20 years. Childhood LCH is a well-treatable disease and the survival rate is high. Even disseminated diseases have a quite good prognosis in childhood.

Glucocorticoid-induced apoptosis and treatment sensitivity in acute lymphoblastic leukemia of children

Sensitivity of leukemic blasts to steroid therapy is one of the prognostic factors in acute lymphoblastic leukemia (ALL) in children. We examined the number of steroid receptors and the increase in the apoptotic index in peripheral blast cells after administration of prednisolone monotherapy in 21 children with ALL. A new diagnostic method was established based on determination of the apoptotic index in peripheral blood lymphoblasts to evaluate the steroid sensitivity of leukemic cells during the first day of therapy. The increase in apoptotic ratio, analyzed by morphologic and/or flow cytometric studies, was most expressed in the first 6 hours of treatment. The apoptotic ratio showed a good correlation with the clinical response. The number of steroid receptors (gcRs) on the blast cells was also examined, but it proved to be less informative than the in vivo steroid response itself.

Activation of T cell cytotoxicity against autologous common acute lymphoblastic leukemia (cALL) blasts by CD3xCD19 bispecific antibody

To develop an effective immunotherapy for B-lineage acute lymphoblastic leukemia (ALL), bispecific monoclonal antibodies (bsAb) were raised by cell fusion of two hybridoma cell lines secreting CD3 and CD19 antibodies. The resulting bispecific antibody contains two different specificities within a single antibody molecule. One binding site (CD3) activates the T cells via the T cell receptor complex, whereas the second binding site (CD19) targets the cytolytic T cells to malignant B cells. Leukemic blasts from children with B-lineage ALL showed stable and strong CD19 expression. CD3xCD19 bsAb were used to activate peripheral blood mononuclear cells (PBMC) from healthy donors or from patients with ALL during remission. Cytotoxic activity against autologous ALL cells by PBMC was induced upon addition of 100 ng/ml CD3xCD19 bsAb after 3 days of preincubation. Costimulation through CD28 increased T cell proliferation to some extent, but did not increase cytotoxic activity of PBMC against leukemic blasts. We present evidence for an effective and specific activation of resting human T lymphocytes by CD3xCD19 bsAb in vitro. Activation of cytotoxic effector T cells is feasible by preincubation with bsAb CD3xCD19 alone and does not rely on additional external costimulation. Thus, targeting of T cell cytotoxicity towards leukemic blasts via CD3xCD19 bsAb may represent a promising strategy for immunotherapy of B-lineage ALL.