Comprehensive clinicopathological, molecular, and methylation analysis of mesenchymal tumors with NTRK and other kinase gene aberrations

Alterations in kinase genes such as NTRK1/2/3, RET, and BRAF underlie infantile fibrosarcoma (IFS), the emerging entity 'NTRK-rearranged spindle cell neoplasms' included in the latest WHO classification, and a growing set of tumors with overlapping clinical and pathological features. In this study, we conducted a comprehensive clinicopathological and molecular analysis of 22 cases of IFS and other kinase gene-altered spindle cell neoplasms affecting both pediatric and adult patients. Follow-up periods for 16 patients ranged in length from 10 to 130 months (mean 38 months). Six patients were treated with targeted therapy, achieving a partial or complete response in five cases. Overall, three cases recurred and one metastasized. Eight patients were free of disease, five were alive with disease, and two patients died. All cases showed previously reported morphological patterns. Based on the cellularity and level of atypia, cases were divided into three morphological grade groups. S100 protein and CD34 were at least focally positive in 12/22 and 14/22 cases, respectively. Novel PWWP2A::RET, NUMA1::RET, ITSN1::RAF1, and CAPZA2::MET fusions, which we report herein in mesenchymal tumors for the first time, were detected by RNA sequencing. Additionally, the first uterine case with BRAF and EGFR mutations and CD34 and S100 co-expression is described. DNA sequencing performed in 13 cases uncovered very rare additional genetic aberrations. The CNV profiles showed that high-grade tumors demonstrate a significantly higher percentage of copy number gains and losses across the genome compared with low- and intermediate-grade tumors. Unsupervised clustering of the tumors' methylation profiles revealed that in 8/9 cases, the methylation profiles clustered with the IFS methylation class, irrespective of their clinicopathological or molecular features. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The effect of physical exercise and dairy probiotics (Lactobacillus casei) on gut microbiome in childhood cancer survivors

Gut microbial dysbiosis persists months after intensive cancer treatment in children and adolescents. This prospective study compared the intestinal microbiome of children 1-3 years after completion of Berlin-Frankfurt-Münster protocol (BFM)-based pediatric ALL (PALL) treatment and healthy controls. To induce a favorable shift in the bacterial composition of the intestines in PALL with gut microbiome disruptions, 8 weeks of physical activity and probiotic consumption were used. Blood analyses and 16S rRNA sequencing for the gut microbiome were performed on 16 pediatric cases and 16 healthy controls. Significant differences in bacterial diversity were found between pre- and post-intervention, respectively (Shannon index, 3.22±0.45 vs. 3.47±0.24, p=0.04; Simpson index, 0.10±0.05 vs. 0.06±0.02, p=0.02; and Chao1 index, 693.88±238.58 vs. 794.23±116.34, p=0.04). Furthermore, the increase in the relative abundance of Lactobacillus casei (5.04E-03±1.62E-02 vs. 2.92E-02±5.03E-02, p=0.04) and the increase in some strains of Veillonella, a bacterial genus recently linked to improved physical fitness, were identified. Promisingly, the exercise program combined with dairy probiotics increased bacterial richness and diversity.

Gut Microbiome Suffers from Hematopoietic Stem Cell Transplantation in Childhood and Its Characteristics Are Positively Associated with Intra-Hospital Physical Exercise

Gut microbiome impairment is a serious side effect of cancer treatment. The aim of this study was to identify the effects of hematopoietic stem cell transplantation (HSCT) treatment on gut microbiota composition in children with acute lymphoblastic leukemia (ALL). Fecal microbiotas were categorized using specific primers targeting the V1-V3 region of 16S rDNA in eligible pediatric ALL patients after HSCT (n = 16) and in healthy controls (Ctrl, n = 13). An intra-hospital exercise program was also organized for child patients during HSCT treatment. Significant differences in gut microbiota composition were observed between ALL HSCT and Ctrl with further negative effects. Plasma C-reactive protein correlated positively with the pathogenic bacteria Enterococcus spp. and negatively with beneficial bacteria Butyriccocus spp. or Akkermansia spp., respectively (rs = 0.511, p = 0.05; rs = -0.541, p = 0.04; rs = -0.738, p = 0.02). Bacterial alpha diversity correlated with the exercise training characteristics. Therefore, specific changes in the microbiota of children were associated with systemic inflammation or the ability to exercise physically during HSCT treatment.

Dinutuximab beta in the treatment of high-risk neuroblastoma: A follow-up of a case series in Bratislava

Despite therapeutic advances, high-risk neuroblastoma is still associated with a poor long-term prognosis. Immunotherapy with the anti-GD2 antibody dinutuximab beta has recently been added to the standard of care for patients with high-risk neuroblastoma in our center in Bratislava, and our initial experience with dinutuximab beta has been reported previously. Here we provide a follow-up on the outcomes of 7 patients who were treated with dinutuximab beta under clinical practice conditions at our center.Medical records of 31 patients diagnosed with neuroblastoma between 2017 and 2020 at the Children's Hematology and Oncology Clinic in Bratislava were retrospectively reviewed and 7 patients with high-risk neuroblastoma who were treated with dinutuximab beta were identified. All 7 patients received dinutuximab beta as continuous infusion over 10 days at a dose of 10 mg/m2/day for 5 cycles, following induction and consolidation therapy. Supportive therapy was administered to manage adverse events. Clinical outcomes and treatment tolerance were evaluated.Six of 7 patients treated with dinutuximab beta achieved complete remission, with a median duration of response of 21.5 months as of January 2022, and 1 displayed stable disease 21 months after treatment completion. Treatment was tolerable in most patients, with the majority of adverse events managed with supportive care.Dinutuximab beta is an effective immunotherapy for patients with high-risk neuroblastoma in routine clinical practice when coupled with optimal supportive management of adverse events.

Primary lymphoma of the pancreas – a case report

Súhrn: Bolesti brucha patria medzi pomerne časté symptómy u adolescentov. Príčiny, ktoré sa podieľajú na bolestiach brucha, sú pestré a tým aj diferenciálna dia­gnostika je pomerne rozsiahla a zložitá. To súvisí pravdepodobne s tým, že brucho zaberá pomerne veľkú oblasť, obsahuje množstvo orgánov, štruktúr, systémov vrátane lymfatických uzlín, ktoré generalizovane reagujú na infekciu, či nádorové ochorenia. V našej kazuistike opisujeme prípad 17-ročného pacienta s náhlymi bolesťami brucha, chudnutím, vracaním a ikterom. V rámci diferenciálnej dia­gnostiky sa realizovali laboratórne a zobrazovacie vyšetrenia so zameraním na pankreas a hepatobiliárny trakt, kde sa zobrazila zväčšená hlava a chvost pankreasu, peripankreatická lymfadenopatia s vedľajším nálezom drobných ložísk na obličkách. V úvode sa suponovala skôr hereditárna pankreatitída a pseudotumory na obličkách, vzhľadom na vek pacienta bol menej pravdepodobný tumor pankreasu a metastázy. Definitívna dia­gnóza bola stanovená odberom bio­ptických vzoriek pankreasu pomocou endosonografického vyšetrenia. Histologický a cytologický nález preukázal prítomnosť lymfocytárnych blastických buniek, charakteru CD20+ B-NHL, konštatovaný difúzny veľkobunkový B-lymfóm pankreasu (DLBCL – diffuse large B cell lymphoma). Staging ochorenia nepreukázal inflitráciu malígnych buniek v kostnej dreni a centrálnej nervovej sústave. Promptne stanovená dia­gnóza a podaná príslušná onkologická liečba (chemoterapia v kombinácii s monoklonálnou protilátkou) zabezpečila pacientovi návrat do každodenného života a je nevyhnutným predpokladom priaznivej prognózy pacienta. Kľúčové slová: bolesti brucha – žltačka – difúzny veľkobunkový B-lymfóm

Implementation of immunotherapy into the treatment of neuroblastoma - single center experience with the administration of dinutuximab and management of its adverse effects

BACKGROUND

Neuroblastoma is the most common extracranial solid tumour of childhood with extremely heterogeneous bio-logical and clinical behaviour. Despite advances in its treatment, the long-term prognosis of patients with a high-risk and relapsed neuroblastoma remains poor. The implementation of immunotherapy into the treatment protocols has the potential to improve it. Dinutuximab, a chimeric monoclonal antibody, leads to the apoptosis of tumour cells through binding to the GD2 receptor. The article aim is to present the first experience of our centre with dinutuximab treatment.

PATIENTS AND METHODS

In 2018-2019, we administered 31 cycles of dinutuximab to seven patients. Five patients with high-risk neuroblastoma received dinutuximab in the first line, in two patients with relapse, dinutuximab was administered in the second line of treatment. To evaluate the toxicity of the treatment, the nursing records of patients during immunotherapy were retrospectively analysed.

RESULTS

Two patients treated with dinutuximab in the first line are in complete remission, three patients achieved a partial response. Both patients with relapsed neuroblastoma were dia-gnosed with a second relapse after immunotherapy and died of disease progression. The treatment tolerance was acceptable in most patients - in six patients adverse events were managed with adequate supportive care. These were mainly symptoms of capillary leak syndrome, pain and hypersensitivity reactions. In one patient, the treatment was discontinued due to severe neurotoxicity.

CONCLUSION

Dinutuximab has a proven benefit in the eradication of the minimal residual disease in the treatment of neuroblastoma. Immunotherapy is currently the standard for first-line treatment of high-risk neuroblastoma. Its role in the treatment of relapsed neuroblastoma is a subject of several ongoing studies as well as the optimization of therapeutic regimens. Dinutuximab administration is associated with a considerable risk of severe adverse reactions, so the treatment belongs to the hands of an experienced paediatric oncology centre.

Invasive Rhino-Orbito-Cerebral Mucormycosis in Pediatric Patient with Acute Leukemia

BACKGROUND

Invasive fungal infections are a life-threatening complication of cancer treatments, especially in hemato-oncological patients. Mucormycosis is the third leading cause of invasive fungal infections after Aspergillus and Candida infections. The first clinical symptoms are usually non-specific, which can lead to a late diagnosis and delayed therapy.

PURPOSE

The objective of this report is to summarize data in the literature about mucormycosis and to present a case report of a patient with acute lymphoblastic leukemia, who developed this infection at our center. Risk factors for the development of mucormycosis, clinical symptoms, radiology, laboratory results, and outcome were retrospectively evaluated.

CASE

We describe a 6-years-old female patient with acute lymphoblastic leukemia. During the induction phase of therapy, the patient developed febrile neutropenia and did not respond to therapy with a combination of antibiotics and supportive treatment. Pansinusitis and orbitocellulitis developed. Examination of the biological material revealed that the etiological agent was a Rhizopus sp. The patient was treated with a combination of antimycotic drugs, but the infection disseminated to the central nervous system. She underwent radical surgical resection of the affected tissue. At this time, she is still under treatment with antimycotic and oncology agents, but is in remission of the main diagnosis and in good clinical condition.

CONCLUSION

Mucormycosis is an invasive fungal infection with high morbidity and mortality. Early diagnosis and initiation of effective therapy using a combination of amphotericin B administration and surgery are necessary to obtain a favorable outcome. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.

Backtracked analysis of preleukemic fusion genes and DNA repair foci in umbilical cord blood of children with acute leukemia

The first event in origination of many childhood leukemias is a specific preleukemic fusion gene (PFG) that arises, often in utero, in hematopoietic stem/progenitor cells (HSPC) from misrepaired DNA double strand break (DSB). An immanently elevated level of DSB and impaired apoptosis may contribute to origination and persistence of PFG and donor cell-derived leukemia in recipients of allogeneic transplantation of umbilical cord blood (UCB). We investigated DSB, apoptosis and PFG in the backtracked UCB cells of leukemic patients. RNA from UCB of three patients with acute lymphoblastic leukemia, patient with acute megakaryoblastic leukemia and Down syndrome, and four healthy children was screened for common PFG by RT-qPCR. Presence of PFG was validated by sequencing. Endogenous γH2AX and 53BP1 DNA repair foci, cell populations, and apoptosis were analyzed in UCB CD34+/- cells with imaging and standard flow cytometry. We found MLL₂-AF4 and BCR-ABL (p190) fusion genes in UCB of two out from four pediatric patients, apparently not detected at diagnosis, while UCB cells of TEL-AML1+ ALL patient were tested negative for this PFG and no PFG were detected in UCB cells of healthy children. No significant difference in DNA damage and apoptosis between UCB CD34+/- cells from healthy children and leukemic patients was observed, while Down syndrome trisomy increased DNA damage and resulted in distribution of cell populations resembling transient abnormal myelopoiesis. Our findings indicate increased genetic instability in UCB HSPC of leukemic patients and may be potentially used for diagnostics and exclusion of possibly affected UCB from transplantation.