Revisions to the International Neuroblastoma Response Criteria: A Consensus Statement From the National Cancer Institute Clinical Trials Planning Meeting

Recommendations for the use of nuclear medicine imaging in patients with neuroblastoma

Neuroblastoma (NB) is the most common extracranial solid cancer in children. Despite intensive multimodality treatment, long-term survival of patients with high-risk NB, which comprises more than half of all cases, remains poor. Nuclear medicine is key in diagnosis, staging, response assessment and long-term follow-up of NB. The emergence of novel tracers and the increasing complexity of studies require updated guidelines for nuclear medicine imaging in NB. Standardising diagnostic techniques are essential for improving study comparability and ensuring test quality. This article aims to provide a comprehensive review of NB radionuclide diagnostic imaging, including its characteristics, accuracy, advantages, and limitations. It offers practical recommendations to multidisciplinary teams responsible for treating patients with NB. This review summarises the opinions of leading experts from the Neuroblastoma Spanish Group within the Spanish Society of Paediatric Haematology and Oncology (SEHOP) and the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM).

A Phase II Trial of Naxitamab plus Stepped-up Dosing of GM-CSF for Patients with High-Risk Neuroblastoma in First Complete Remission

PURPOSE

Naxitamab is a humanized form of the murine anti-GD2 mAb 3F8. In an international trial, naxitamab + GM-CSF was effective against chemoresistant high-risk neuroblastoma (HR-NB), leading to approval by the FDA. We now report results with patients in first complete remission (CR).

PATIENTS AND METHODS

The primary objective of this phase II protocol 16-1643 (Clinicaltrials.gov NCT03033303) was to assess event-free survival of patients with HR-NB in first CR treated with naxitamab + GM-CSF plus isotretinoin. HR-NB was defined as MYCN-amplified disease (any age) or metastatic disease at age >18 months. Cycles of immunotherapy were administered monthly up to five cycles and comprised (i) subcutaneously administered priming doses of GM-CSF 250 μg/m2/day on days -4 to -0 (Wednesday-Sunday), followed by a step-up to 500 μg/m2/day on days +1 to +5 (Monday-Friday) and (ii) naxitamab infused intravenously (30-90") on days +1, +3, and +5 (Monday-Wednesday-Friday, i.e., three doses/cycle). The dosage of naxitamab was 3 mg/kg/infusion (9 mg/kg/cycle, i.e., ∼270 mg/m2/cycle). The dosage of isotretinoin was 160 mg/m2/day started after cycle 2, ×14 days/course, and ×6 courses.

RESULTS

Fifty-nine patients with HR-NB (53 stage 4, 6 stage 3) were enrolled from February 2017 to July 2020. At 36 months, event-free/overall survival rates were 73%/93%, but 50 of 59 patients received after protocol treatment (vaccine and/or difluoromethylornithine). Six of 18 relapses were isolated in the central nervous system. Longer time from diagnosis to enrollment was a significantly adverse prognostic factor (P = 0.04). Twenty-one of 59 patients took no isotretinoin. Treatment was tolerable allowing outpatient administration.

CONCLUSIONS

Naxitamab + GM-CSF is a good option to consolidate first CR of patients with HR-NB, including those who did not undergo autologous stem-cell transplantation. Efforts to prevent central nervous system relapse are warranted.

Characteristics, treatments, and outcomes of adolescents and adults with neuroblastoma: a retrospective study in China

Background

Neuroblastoma (NB) is rare in adolescents and adults, resulting in limited availability of data.

Objectives

We comprehensively investigated the characteristics, treatments, and outcomes of adolescent and adult patients with NB, aiming to provide a more in-depth insight into this disease.

Design

A retrospective, single-center study.

Methods

We retrieved and analyzed the medical data of patients with NB aged 10 years or older at diagnosis who were treated at Sun Yat-sen University Cancer Center between June 2005 and January 2024.

Results

Sixty-five patients (30 males and 35 females) were enrolled, with a median age of 20 years (interquartile range, 14-26 years), including 27 patients aged 10-18 years and 38 patients aged >18 years. Most patients were classified as M-stage disease (n = 40, 61.5%), high-risk (n = 42, 64.6%), and poorly differentiated NB (n = 27, 41.5%). Additionally, 3 (6.7%) patients had MYCN amplification, and 5 (25%) had ALK mutations. The genomic landscape revealed that mutations in the cell cycle and DNA repair pathways are related to chemotherapy sensitivity. After induction therapy, 34 (52.3%) patients achieved complete response (CR). The 5-year progression-free survival (PFS) and overall survival (OS) rates were 33.1% ± 6.9% and 55.1% ± 7.6%, respectively. Patients who achieved CR after induction therapy had superior PFS (p = 0.009), with 5-year PFS rates of 44.0% ± 10.6% compared to 18.5% ± 8.5% in non-CR patients.

Conclusion

Adolescent and adult patients with NB exhibit distinct characteristics, less chemotherapy sensitivity, and poorer outcomes compared to pediatric patients. Achieving CR after induction therapy is associated with better outcomes. Further investigation for new therapies is required.

Longitudinal single-cell multiomic atlas of high-risk neuroblastoma reveals chemotherapy-induced tumor microenvironment rewiring

High-risk neuroblastoma, a leading cause of pediatric cancer mortality, exhibits substantial intratumoral heterogeneity, contributing to therapeutic resistance. To understand tumor microenvironment evolution during therapy, we longitudinally profiled 22 patients with high-risk neuroblastoma before and after induction chemotherapy using single-nucleus RNA and ATAC sequencing and whole-genome sequencing. This revealed profound shifts in tumor and immune cell subpopulations after therapy and identified enhancer-driven transcriptional regulators of neuroblastoma neoplastic states. Poor outcome correlated with proliferative and metabolically active neoplastic states, whereas more differentiated neuronal-like states predicted better prognosis. Proportions of mesenchymal neoplastic cells increased after therapy and a high proportion correlated with a poorer chemotherapy response. Macrophages significantly expanded towards pro-angiogenic, immunosuppressive and metabolic phenotypes. We identified paracrine signaling networks and validated the HB-EGF-ERBB4 axis between macrophage and neoplastic subsets, which promoted tumor growth through the induction of ERK signaling. These findings collectively reveal intrinsic and extrinsic regulators of therapy response in high-risk neuroblastoma.

GPOH Guidelines for Diagnosis and First-line Treatment of Patients with Neuroblastic Tumors, update 2025

The clinical course of neuroblastoma is more heterogeneous than any other malignant disease. Many low-risk patients experience regression after limited or even no chemotherapy. However, more than half of high-risk patients die from disease despite intensive multimodal treatment. Precise disease characterization for each patient at diagnosis is key for risk-adapted treatment. The guidelines presented here incorporate results from national and international clinical trials to produce recommendations for diagnosing and treating neuroblastoma patients in German hospitals outside of clinical trials.

Evaluating Bone Marrow Involvement in Pediatric Neuroblastoma: Traditional Methods and Emerging Technologies-A Systematic Review

Neuroblastoma (NB) is the most common extracranial solid neoplasm affecting the pediatric population. It shows a high prevalence of bone marrow infiltration (BMI), which substantially impacts the disease's staging and prognostic assessment. Conventional methodologies, including bone marrow biopsy (BMB) and aspirate (BMA), have been extensively employed; nevertheless, the advent of novel technologies presents a promising avenue for diagnostic accuracy. This systematic review is designed to critically analyze and compare the established techniques (BMB and BMA) versus novel diagnostic approaches-such as immunocytology, RT-qPCR, and multiparametric flow cytometry (FCM), along with functional imaging like MIBG scintigraphy and FDG-PET/CT-in assessing BMI in pediatric NB. An exhaustive search was performed across the PubMed and Embase databases, identifying 2694 scholarly articles. Following a meticulous screening process and the application of inclusion criteria centered on diagnostic accuracy, sensitivity, and specificity about BMI, a total of 140 articles were selected for qualitative analysis. While BMB remains the gold standard for diagnosing and staging BMI in NB, recent advances in molecular techniques and functional imaging have shown superior sensitivity and specificity. Immunocytology and RT-qPCR can detect minimal residual disease (MRD) with higher sensitivity compared to traditional methods. Functional imaging modalities, particularly FDG-PET/CT and MIBG scintigraphy, have demonstrated improved accuracy in assessing bone marrow involvement with the added advantage of evaluating the entire bone marrow, overcoming the limitations of focal sampling in BMB. The integration of advanced molecular diagnostics and functional imaging with traditional biopsy methods enhances the accuracy of BMI in NB.

131I-mIBG therapy in relapsed/refractory neuroblastoma: an old bridge to the future

BACKGROUND

The prognosis of relapsed/refractory (R/R) neuroblastoma (NB) is still dismal. The role of iodine-131 meta-iodobenzylguanidine (131I-mIBG) treatment as a tool to reduce tumour burden before novel immunotherapies is not defined.

PATIENTS AND METHODS

Patients with R/R NB were included in a prospective observational study based on two infusions of 131I-mIBG plus melphalan (110 mg/m2), supported by autologous haematopoietic stem cell rescue. The activity of the first administration was 444 MBq (12 mCi/kg), while the second dose was modulated to reach a whole-body absorbed dose of 4 Gy. The International Neuroblastoma Response Criteria (INRC) were used for response.

RESULTS

Twenty-six patients with a median age of 5.9 years (range 2.5-17.2 years) were treated. Twenty-three patients presented a bone/bone marrow involvement, and 21 patients presented an uptake at primary site or at soft-tissue sites. The median International Society of Paediatric Oncology Europe Neuroblastoma Group (SIOPEN) skeletal score was 10 (range 1-70). The main recorded toxicities were haematological, with no toxic deaths and only one grade 4 mucositis. Hypothyroidism was reported in 6 patients of the 14 alive patients. The overall response rate was 48% [95% confidence interval (CI) 28% to 69%] with only one progression; after treatment the median SIOPEN skeletal score was 6 (range 0-70) with a median reduction of 35% (range 4.3%-100%). Overall, 52% (95% CI 32% to 73%) of patients achieved/maintained a SIOPEN skeletal score <7 and a soft-tissue lesion <5 cm was seen in 67% (95% CI 43% to 91%). After this treatment, 65% of patients underwent GD2-targeting chimeric antigen receptor (CAR)-T-cell therapy and 50%, high-dose chemotherapy with busulfan and melphalan. The 3-year overall survival was 55% (95% CI 33% to 73%) and event-free survival was 42% (95% CI 23% to 60%).

CONCLUSION

The 131I-mIBG therapy plus melphalan is confirmed to be effective to reduce/control tumour burden. Further studies are needed to clarify the role and timing of this treatment and to integrate its role in the strategy of CAR-T cells.

Theranostics for Neuroblastoma: Making Molecular Radiotherapy Work Better

Despite improvements in neuroblastoma treatment, survival figures lag behind those of many other childhood malignancies. New treatments, and better use of existing treatments, are essential to reduce mortality. Neuroblastoma expresses several molecular targets for radionuclide imaging and therapy, of which the most widely exploited is the norepinephrine transporter. [123I]metaiodobenzylguanidine (MIBG) imaging and [131I]MIBG treatment, which target this physiologic pathway, have been in clinical practice for 40 y. Although therapy outcomes have been favorable, [131I]MIBG use has not yet been optimized. Somatostatin receptors and the disialoganglioside are alternative targets, but their use remains experimental. The charity Children's Cancer Research Fund organized a workshop bringing together a broad range of scientists including radiochemists, radiobiologists, radiation physicists, clinical researchers including pediatric oncologists and nuclear medicine physicians, and patient advocates from the United Kingdom, United States, and continental Europe to share their experiences with molecular imaging and radiotherapy of neuroblastoma and discuss potential ways of improving treatment outcomes and access. These include development of alternative vectors targeting somatostatin receptors and disialoganglioside, isotopes such as α-particle and Auger electron emitters with different radiation characteristics, and combinations with external-beam radiotherapy, immunotherapy, and DNA damage repair inhibitors. Barriers to progress discussed included the unpredictable radioisotope supply, production of novel radiopharmaceuticals, lack of data regarding which are the best combination therapies, and insufficient clinical facilities. The aim was to stimulate the development and assessment of more effective treatments.

A clinical observational study of dinutuximab beta as first-line maintenance treatment for patients with high-risk neuroblastoma in China

BACKGROUND

High-risk neuroblastoma (HR-NB) is associated with high metastatic and relapse rates that require intensive multimodal treatment. We evaluated the efficacy and safety of dinutuximab beta as first-line maintenance immunotherapy in pediatric patients with HR-NB in real-world clinical settings in China.

METHODS

We retrospectively reviewed the clinical records of pediatric patients with newly diagnosed HR-NB in the hospital from October 2021 to November 2023. Patients treated with dinutuximab beta in combination with granulocyte-macrophage colony-stimulating factor (GM-CSF) and isotretinoin as the first-line maintenance therapy were included in this study. Among patients with residual disease after completing induction and consolidation treatment, those with partial response (PR) or very good partial response (VGPR) except for bone marrow (BM) residue were also administrated vincristine/irinotecan/temozolomide (VIT) chemotherapy.

RESULTS

Fifty-one patients with newly diagnosed HR-NB who achieved at least PR before immunotherapy were evaluated. At the end of immunotherapy, the objective response rate (ORR) in 33 patients with evidence of disease was 60.6% (95% confidence interval (CI), 42.1-77.1%) and the complete response rate (CRR; n = 18) was 54.5% (95% CI, 36.4-71.9%). The 2-year event-free survival (EFS) rate and overall survival (OS) rate were 80.1% (95% CI, 66.2-88.8%) and 97.6% (95% CI, 84.3-99.7%), respectively. The 2-year EFS rate was higher in patients with CR (94.4%; 95% CI, 66.6-99.2%) than in non-CR patients (72.6%; 95% CI, 53.9-84.7%). Dinutuximab beta was well tolerated in patients and had fewer side effects, which decreased over time. Co-treatment of dinutuximab beta with VIT chemotherapy did not require discontinuation in patients undergoing immunochemotherapy.

CONCLUSION

The study showed promising efficacy and safety of dinutuximab beta as the first-line maintenance immunotherapy for pediatric patients with HR-NB. Notably, the combination of dinutuximab beta with GM-CSF and VIT chemotherapy could be used for treating patients who did not achieve CR after previous multimodal therapy.

Tumor Dose-Response Relationship of [131I]MIBG Therapy in Patients with Neural Crest Tumors by Means of [124I]MIBG PET

[131I]Metaiodobenzylguanidine (MIBG) therapy in patients with neural crest tumors has demonstrated sustained control of catecholamine-associated hypertension and corresponding partial response. Details on how neural crest tumors respond to an absorbed dose delivered by [131I]MIBG-targeted therapies is insufficiently known. The primary aim of this retrospective study was to assess the tumor dose-response relationship by means of quantitative analysis of [124I]MIBG PET data. Methods: The tumor dose-response relationship was studied in patients with advanced malignant pheochromocytoma, neuroblastoma, or paraganglioma receiving [131I]MIBG treatment, as well as pretherapeutic and follow-up [124I]MIBG-based dosimetry. [124I]MIBG PET imaging was performed around 4, 24, 48, and 120 h after injection. Lesion uptake was projected to [131I]MIBG for every time point, and respective time-integrated activity coefficients (TIACs) for [131I]MIBG were calculated and used for tumor-absorbed dose estimation. Functional response was denoted for decrease of maximal lesion uptake or TIAC by at least 30% in the follow-up examination. In a consecutive analysis, the predictive value of a single tumor-uptake assessment from PET imaging at 24 h after administration was investigated with respect to receiving the derived target dose. Results: In total, 46 lesions from 9 patients were available for dose-response analysis. The mean ± SD tumor-absorbed dose coefficient was 13.4 ± 15.4 Gy/GBq (median, 7.2 Gy/GBq; range, 1.1-64.7 Gy/GBq). A high correlation (-0.60, P < 0.001) was found between uptake decrease and tumor dose. In addition, a very high correlation (0.91, P < 0.001) was found between uptake and TIAC decrease. The estimated targeted tumor dose was 200 Gy, that is, the dose at which the response rate exceeded the 90% threshold. A single 24-h uptake assessment showed predictive value with respect to receiving the target dose. Conclusion: This study demonstrated a clear correlation between tumor-absorbed dose and functional response in [131I]MIBG therapy and proposes a target dose for response at the tumor level.

Cellular morphometric biomarkers and large language model predict prognosis and treatment response in neuroblastoma patients: A retrospective and double-blind prospective single arm clinical study

BACKGROUND

The heterogeneity of Neuroblastoma (NB) leads to variation in response to treatment and outcomes. The aim of the current study is to discover AI-empowered cellular morphometric biomarkers (CMBs), to establish the corresponding CMB risk score (CMBRS), CMB risk group (CMBRG), large language model driven CMB risk score (CMB-LLM-RS), and large language model driven CMB risk group (CMB-LLM-RG), and to investigate and validate their prognostic and predictive power in NB.

METHODS

In this study, the retrospective cohort enrolled 84 primary NBs between 1/2020 and 12/2021, followed up through 11/22/2024; the prospective cohort enrolled 67 primary NBs between 1/2022 and 7/2023, followed up through 11/22/2024.

RESULTS

We identified 9 CMBs from a retrospective NB cohort, enabling the CMBRS, CMBRG, CMB-LLM-RS, and CMB-LLM-RG. Both CMBRG and CMB-LLM-RG are significantly associated with prognosis (p < 0.0001) and treatment response (p < 0.0001). Furthermore, we double-blindly validated the predictive power of CMBRG and CMB-LLM-RG in a prospective NB cohort, which confirms their potential value in real clinical settings. Importantly, CMBRG provides clinical value independent of the International Neuroblastoma Risk Group (INRG) classification system in both retrospective and prospective NB cohorts (p < 0.05); and the combination of CMBRG and INRG significantly increases prognostic and predictive performance for NB patients.

CONCLUSIONS

These findings suggest that CMBRG and CMB-LLM-RG have prognostic and predictive value for NB and warrants evaluation in larger multicenter cohorts.

Donor-derived GD2-specific CAR T cells in relapsed or refractory neuroblastoma

Allogeneic chimeric antigen receptor (CAR) T cells targeting disialoganglioside-GD2 (ALLO_GD2-CART01) could be a therapeutic option for patients with relapsed or refractory, high-risk neuroblastoma (r/r HR-NB) whose tumors did not respond to autologous GD2-CART01 or who have profound lymphopenia. We present a case series of five children with HR-NB refractory to more than three different lines of therapy who received ALLO_GD2-CART01 in a hospital exemption setting. Four of them had previously received allogeneic hematopoietic stem cell transplantation. All patients experienced grade 2 or 3 cytokine release syndrome and one grade 2 neurotoxicity. Moderate acute graft-versus-host-disease occurred in four patients. ALLO_GD2-CART01 persisted for >6 weeks. Post-treatment, two complete responses were achieved and one maintained; in addition, one partial response and one stable disease were observed. Comparing the transcriptomic profiles obtained by RNA sequencing analyses of drug products with patient-matched, peripheral blood ALLO_GD2-CART01 collected at expansion, we found upregulation of genes associated with T cell activation and migration. In addition, after infusion, transcriptomic signaling analysis showed enrichment of genes involved in response to decreased oxygen levels, humoral immune response, cell polarization and immune-synapse formation. In comparison to autologous CAR T cells, ALLO_GD2-CAR T cells were characterized by pathways associated with T cell proliferation, immune-synapse formation and cell chemotaxis. The safety and efficacy of ALLO_GD2-CART01 in children with r/r HR-NB deserve further investigation in a prospective trial.

131I-mIBG therapy in relapsed/refractory neuroblastoma: A weapon from the future past

Neuroblastoma (NB) is the most common extracranial solid tumor in children, with variable outcomes ranging from spontaneous remission to high-risk cases often leading to relapse or refractory disease. Approximately 50 % of patients with NB have high-risk features, often experiencing relapse or refractory disease despite intensive treatments and the prognosis remains poor, with long-term event-free survival (EFS) rates below 10 %,Radioactive iodine-labeled meta-iodobenzylguanidine (¹³¹I-mIBG) therapy, leveraging NB cells' radiosensitivity and expression of the norepinephrine transporter (NET), has shown promise in treating relapsed or refractory NB. Since 1985, ¹³¹I-mIBG has been studied to determine the maximum tolerated dose and side effects, with recent trials exploring its use in front-line treatment. Our systematic review, based on MEDLINE, EMBASE, and Cochrane CENTRAL databases up to December 2023, evaluates the effectiveness and toxicity of ¹³¹I-mIBG therapy in relapsed/refractory NB. It also discusses its potential role in conjunction with emerging therapies like CAR-T cells, haploidentical stem cell transplantation, and dinutuximab beta.

Adverse Reaction Reporting for Naxitamab in Chinese Expanded Access Treatment for Relapsed/Refractory High-Risk Neuroblastoma at the Children's Hospital of Fudan University

BACKGROUND

The humanized anti-disialoganglioside-2 monoclonal antibody naxitamab was approved in the USA in 2020 for the treatment of patients with relapsed/refractory high-risk neuroblastoma, limited to the bone or bone marrow, in combination with granulocyte-macrophage colony-stimulating factor. Treatment with naxitamab under expanded access was initiated by physicians from the Children's Hospital of Fudan University, Shanghai, China, in August 2021.

OBJECTIVE

We reviewed all suspected adverse reactions (ARs) reported to the Y-mAbs Argus Global Pharmacovigilance Safety Database for patients treated with naxitamab under expanded access in China from 1 August 2021 to 31 July 2022.

METHODS

We assessed patient demographics and the safety profile of naxitamab over multiple treatment cycles.

RESULTS

At the data cutoff, 41 patients with relapsed/refractory high-risk neuroblastoma had received a total of 150 treatment cycles (451 infusions) of naxitamab. The median number of cycles completed was three; 13 patients (32%) were receiving ongoing naxitamab treatment. The median patient age was 3 years (range 1-9 years) and 63% were female. Overall, ARs were reported in 89/150 cycles (59%); serious ARs were reported in 23/150 cycles (15%). The cumulative reporting rate (ARs/cycle) decreased after 3 versus 12 months of expanded access: all ARs (8.7-4.6), serious ARs (0.9-0.3), hypotension (1.4-1.0), flushing (0.7-0.5), cough (0.6-0.3), pain (0.5-0.2), and hypoxia (0.3-0.2).

CONCLUSIONS

During the first 12 months of expanded access treatment in China, 41 patients received naxitamab therapy with a cumulative 451 infusions administered. Over the course of this expanded access program, a reduction in the AR rate, including serious ARs, was observed as more patients were initiated and proceeded to later treatment cycles. While additional research is needed, the observed decrease in the AR rate may be attributed to clinicians' increased knowledge of AR management and hands-on experience with naxitamab-treated patients.

Safety observations in neuroblastoma patients undergoing 18 F- m FBG PET

OBJECTIVE

Limited safety data have been published on fluorine-18 ( 18 F) meta-fluorobenzylguanidine ( m FBG), a new PET radiopharmaceutical for imaging neural crest and neuroendocrine tumors. As part of a prospective clinical trial, safety data in patients with neuroblastoma were collected and analyzed.

METHODS

Between April 2015 and January 2022, 27 patients with neuroblastoma underwent 18 F- m FBG PET imaging as part of an ongoing single-center phase 1/2 trial (NCT02348749). Pre- and postinjection safety assessments were performed, including vital sign measurement and observation for occurrence of adverse events (AEs).

RESULTS

m FBG administration resulted in no significant changes in measured vital signs. Two subjects had transient, grade 1 facial flushing shortly after the administration, which resolved within a few minutes. Neither subject had a clinically significant change in pulse or blood pressure on postadministration measurements.

CONCLUSION

In this investigation of the potential clinical utility of m FBG PET imaging, no significant adverse safety signals were noted. Two mild, self-limited AEs were observed, without associated changes in vital signs. No grade 2 or higher AEs were noted. The findings are consistent with a favorable safety profile for m FBG in the target population of patients with neuroblastoma.

Management and outcome of children with high-risk neuroblastoma: insights from the Spanish Society of Pediatric Hematology and Oncology (SEHOP) neuroblastoma group on refractory and relapse/progressive disease

PURPOSE

Outcome for children with refractory and relapse/progressive high-risk neuroblastoma (HR-NB) remains poor, without an internationally agreed standard second-line approach. Heterogeneity in patients' disease and treatment strategies challenges clinical management. The survival rate for patients with resistant disease does not exceed 20% at 5 years. The study's aim was to analyze refractory and progressive HR-NB patients in a real-world setting to evaluate current clinical practices and optimize future approaches.

METHODS

Data from patients diagnosed with refractory and relapse/progressive (R/R-P) HR-NB between January 2019 and December 2021 at six of the major Spanish neuroblastoma treating hospitals were collected and analyzed.

RESULTS

A total of 67 episodes of R/R-P HR-NB were included. Treatments applied included chemotherapy (97%), immunotherapy (48%), consolidation (21%), local treatment (surgery and/or radiotherapy) (45%) and maintenance (16%), and were administered within a clinical trial (CT) in 34% of the episodes. Biopsy was performed in 37% of the tumors and 30% were profiled. Event-free survival (EFS) in our cohort was 20.9% and overall survival (OS) 32%. Significant survival advantage (in both OS and EFS) was observed in refractory episodes compared to relapse/progressive, in first events compared to successive, and when response or disease stabilization was achieved. MYCN status, presence of lymph node metastases, use of irinotecan or topotecan, and radiotherapy were also univariate predictors of OS.

CONCLUSIONS

Treatment of refractory and relapse/progressive HR-NB is highly heterogeneous. We confirm a poor outcome, although certain epidemiological and treatment-related factors have prognostic value. Molecular profiling and inclusion in CTs should be improved.

A phase 1 dose-escalation study of LY3295668 erbumine as monotherapy and in combination with topotecan and cyclophosphamide in children with relapsed/refractory neuroblastoma

BACKGROUND

This study evaluated the safety, pharmacokinetics, and antitumor activity of LY3295668 erbumine as monotherapy and combination therapy in children with relapsed/refractory neuroblastoma.

METHODS

Patients aged 2-21 years who had relapsed/refractory neuroblastoma were enrolled. LY3295668 erbumine was evaluated at two dose levels (12 and 15 mg/m2) and administered orally twice daily continuously as monotherapy and in combination with intravenous topotecan and cyclophosphamide in 28-day cycles.

RESULTS

Twenty-five patients were treated. No dose-limiting toxicity occurred in monotherapy; one patient had dose-limiting toxicities in the combination therapy cohort (grade 3 mucositis and grade 4 neutropenia). The recommended phase 2 dose for both monotherapy and combination therapy was 15 mg/m2. Twenty-two patients (88%) had one or more treatment-related adverse event(s) (TRAEs), and 18 (72%) experienced grade ≥3 TRAEs. Myelosuppression was the most common high-grade TRAE observed in the combination therapy cohort. At both dose levels, steady-state plasma concentrations exceeded xenograft 90% inhibitory concentration levels. In the monotherapy cohort, one patient had a minor response, and one patient had stable disease, both continuing for >12 months. In the combination therapy cohort, two patients had a partial response, two had a minor response, and six had stable disease. Overall, the response rate, according to New Approaches to Neuroblastoma Therapy version 2.0 criteria, was 8%, and the disease control rate was 52%.

CONCLUSIONS

LY3295668 erbumine had a manageable safety profile as monotherapy and in combination therapy. Although proof-of-concept clinical responses were observed, future studies with biomarker-selected populations and/or novel combinations may yield higher response rates with Aurora kinase A inhibition.

The anti-GD2 monoclonal antibody naxitamab plus GM-CSF for relapsed or refractory high-risk neuroblastoma: a phase 2 clinical trial

In this single-arm, non-randomized, phase 2 trial (NCT03363373), 74 patients with relapsed/refractory high-risk neuroblastoma and residual disease in bone/bone marrow (BM) received naxitamab on Days 1, 3, and 5 (3 mg/kg/day) with granulocyte-macrophage colony-stimulating factor (Days -4 to 5) every 4 weeks, until complete response (CR) or partial response (PR) followed by 5 additional cycles every 4 weeks. Primary endpoint in the prespecified interim analysis was overall response (2017 International Neuroblastoma Response Criteria). Among 26 responders (CR + PR) in the efficacy population (N = 52), 58% had refractory disease, and 42% had relapsed disease. Overall response rate (ORR) was 50% (95% CI: 36-64%), and CR and PR were observed in 38% and 12%, respectively. With the 95% CI lower limit for ORR exceeding 20%, the primary endpoint of overall response was met. Patients with evaluable bone disease had a 58% (29/50) bone compartment response (CR, 40%; PR, 18%). BM compartment response was 74% (17/23; CR, 74%). One-year overall survival and progression-free survival (secondary endpoints) were 93% (95% CI: 80-98%) and 35% (95% CI: 16-54%), respectively. Naxitamab-related Grade 3 adverse events included hypotension (58%) and pain (54%). Overall, naxitamab demonstrated clinically meaningful efficacy with manageable safety in patients with residual neuroblastoma in bone/BM.

Predicted indirectly recognizable HLA epitopes scores and clinical outcomes after haploidentical stem cell transplantation in pediatric patients with relapsed neuroblastoma

Introduction

The Predicted Indirectly ReCognizable HLA Epitopes (PIRCHE) model is a recently developed algorithm that predicts indirect T-cell recognition by calculating the number of such epitopes in donor-recipient pairs.

Methods

In this study, the clinical significance of PIRCHE was evaluated in pediatric patients with relapsed/progressed neuroblastoma undergoing haploidentical stem cell transplantation (haplo-SCT).

Results

A higher PIRCHE-I score was associated with faster platelet recovery (P = 0.007) and lower incidence of hemorrhagic cystitis (13% vs. 41%, P = 0.028) and invasive fungal infections (0% vs. 18%, P = 0.045). Additionally, a higher PIRCHE-I score was significantly associated with better overall survival (OS) (HR 0.57, 95% CI 0.34-0.97, P = 0.038). A higher PIRCHE-II score was associated with better OS (HR 0.57, 95% CI 0.34-0.94, P = 0.028) and reduced progression (HR 0.48, 95% CI 0.30-0.77, P = 0.002). When combined, the PIRCHE-I and PIRCHE-II scores demonstrated an even stronger association with improved OS (HR 0.35, 95% CI 0.15-0.82, P = 0.016). Multivariable analysis confirmed that a higher combined PIRCHE-I and PIRCHE-II score was independently associated with improved OS (combined PIRCHE score HR 0.22, 95% CI 0.06-0.79, P = 0.021), and a higher PIRCHE-II score was significantly associated with reduced progression (HR 0.42, 95% CI 0.25-0.70, P < 0.001).

Conclusion

In conclusion, higher PIRCHE-I and PIRCHE-II scores are linked to better survival outcomes and reduced complications in pediatric haplo-SCT neuroblastoma patients. Incorporating PIRCHE scores into donor selection is expected to optimize transplant outcomes.

Serially Quantifying TERT Rearrangement Breakpoints in ctDNA Enables Minimal Residual Disease Monitoring in Patients with Neuroblastoma

SIGNIFICANCE

Real-time molecular monitoring of TERT-rearranged high-risk neuroblastoma is an unmet clinical need. We tested liquid biopsy-based assays for patient-individualized TERT breakpoint sequences to monitor disease in pediatric patients. Our digital PCR approach provides high resolution of spatial and temporal disease quantification in individual patients and is applicable for clinical routine.

Urinary Catecholamines Predict Relapse During Complete Remission in High-Risk Neuroblastoma

PURPOSE

Urinary catecholamine metabolites are well-known biomarkers for the diagnosis (Dx) of neuroblastoma, but their clinical significance in determining therapy response during treatment is not well established. Therefore, catecholamines are not included in criteria for assessing response and complete remission (CR). This study investigated the use of urinary catecholamines in response monitoring and predicting survival outcomes.

METHODS

From 2005 to 2021, a panel of eight urinary catecholamines were measured in patients with high-risk neuroblastoma at Dx and at standard evaluation moments during treatment. At the same time points, response and CR were assessed according to the revised International Neuroblastoma Response Criteria.

RESULTS

The total cohort consists of 153 high-risk patients, and at least one of the eight metabolites was elevated (ie, catecholamine status positive) in 141 of 146 (97%), 104 of 128 (81%), and 39 of 69 (57%) patients at Dx, postinduction, and at CR, respectively. Primary tumor resection significantly reduced catecholamine levels (P < .01). A positive catecholamine status at Dx, during treatment, and at the end of treatment was not significantly associated with event-free survival (EFS) or overall survival (OS). However, in patients who achieved CR, those with a positive catecholamine status had poor EFS (38% v 80%, respectively; P < .01) and OS (52% v 86%, respectively; P = .01) compared with those with a negative catecholamine status. Notably, 3-methoxytyramine levels at CR seem to be a prognostic marker for poor OS (hazard ratio, 7.5 [95% CI, 2.0 to 28.6]).

CONCLUSION

Catecholamine measurements contribute to the assessment of CR and identifies patients with high-risk neuroblastoma with an increased risk of relapse and death.

Sensitive liquid biopsy monitoring correlates with outcome in the prospective international GPOH-DCOG high-risk neuroblastoma RT-qPCR validation study

BACKGROUND

Liquid biopsies offer less burdensome sensitive disease monitoring. Bone marrow (BM) metastases, common in various cancers including neuroblastoma, is associated with poor outcomes. In pediatric high-risk neuroblastoma most patients initially respond to treatment, but in the majority the disease recurs with only 40% long-term survivors, stressing the need for more sensitive detection of disseminated disease during therapy.

METHODS

To validate sensitive neuroblastoma mRNA RT-qPCR BM testing, we prospectively assessed serial BM samples from 345 international high-risk neuroblastoma patients, treated in trials NB2004 (GPOH) or NBL2009 (DCOG), using PHOX2B, TH, DDC, CHRNA3, and GAP43 RT-qPCR mRNA markers and BM GD2-immunocytology. Association between BM-infiltration levels and event-free survival (EFS) and overall survival (OS) was estimated by using Cox regression models and Kaplan-Meier's methodology.

RESULTS

BM infiltration >10% by RT-qPCR at diagnosis was prognostic for survival (adjusted hazard ratio (HR) 1.82 [95%CI 1.25-2.63] and 2.04 [1.33-3.14] for EFS and OS, respectively). Any post-induction RT-qPCR positivity correlated with poor EFS and OS, with a HR of 2.10 [1.27-3.49] and 1.76 [1.01-3.08] and 5-years EFS of 26.6% [standard error 5.2%] versus 60.4% [6.7] and OS of 43.8% [5.9] versus 65.7% [6.6] for RT-qPCR-positive patients versus RT-qPCR-negative patients. In contrast, post-induction immunocytology positivity was not associated with EFS or OS (HR 1.22 [0.68-2.19] and 1.26 [0.54-2.42]).

CONCLUSION

This study validates the association of not clearing of BM metastases by sensitive RT-qPCR detection with very poor outcome. We therefore propose implementation of RT-qPCR for minimal residual disease testing in neuroblastoma to guide therapy.

Response to induction chemotherapy modifies the effect of conventional prognostic factors in high-risk neuroblastoma: A report from the Children's Oncology Group

Background

Response to induction chemotherapy has been shown to predict outcome in patients with high-risk neuroblastoma (HR-NB), with those achieving a complete response (CR) having superior outcomes.

Methods

We evaluated whether conventional prognostic factors remain prognostic in subsets of patients defined by response to induction. 1244 Patients from four COG high-risk trials were included. End-induction response was coded as CR, partial response (PR) or better, less than PR without progressive disease (PD), and PD. Cox regression models were performed to calculate event-free and overall survival (EFS, OS) hazard ratios, including interaction terms between induction response and prognostic factors including sex, age, stage, primary tumor location, LDH, ferritin, ploidy, MYCN status, ALK status, histology, MKI, grade, and study era.

Results

Among patients who achieved a CR after induction, INSS stage 4 disease and trial era were the only factors that remained significantly associated with inferior OS. For those who achieved less than a PR, adrenal primary site, MYCN amplification, and 1p LOH were associated with inferior outcomes. Multivariable models showed that end-induction response remained prognostic of EFS and OS even after controlling for other factors. Multiple significant statistical interactions were observed between end-induction response and other prognostic factors.

Conclusion

The impact of conventional prognostic factors is not static in patients with HR-NB. Instead, response to induction chemotherapy modifies the effect of conventional prognostic factors. These data can help to further refine prognosis for patients with variable responses to induction and help to identify candidates who might benefit from treatment other than standard post-induction therapy.

Integrative genomic analyses identify neuroblastoma risk genes involved in neuronal differentiation

Genome-Wide Association Studies (GWAS) have been decisive in elucidating the genetic predisposition of neuroblastoma (NB). The majority of genetic variants identified in GWAS are found in non-coding regions, suggesting that they can be causative of pathogenic dysregulations of gene expression. Nonetheless, pinpointing the potential causal genes within implicated genetic loci remains a major challenge. In this study, we integrated NB GWAS and expression Quantitative Trait Loci (eQTL) data from adrenal gland to identify candidate genes impacting NB susceptibility. We found that ZMYM1, CBL, GSKIP and WDR81 expression was dysregulated by NB predisposing variants. We further investigated the functional role of the identified genes through computational analysis of RNA sequencing (RNA-seq) data from single-cell and whole-tissue samples of NB, neural crest, and adrenal gland tissues, as well as through in vitro differentiation assays in NB cell cultures. Our results indicate that dysregulation of ZMYM1, CBL, GSKIP, WDR81 may lead to malignant transformation by affecting early and late stages of normal program of neuronal differentiation. Our findings enhance the understanding of how specific genes contribute to NB pathogenesis by highlighting their influence on neuronal differentiation and emphasizing the impact of genetic risk variants on the regulation of genes involved in critical biological processes.

Quantitative MRI in Childhood Neuroblastoma: Beyond the Assessment of Image-defined Risk Factors

Neuroblastoma commonly occurs in children. MRI is a radiation-free imaging modality and has played an important role in identifying image-defined risk factors of neuroblastoma, providing necessary guidance for surgical resection and treatment response evaluation. However, image-defined risk factors are limited to providing structural information about neuroblastoma. With the evolution of MRI technologies, quantitative MRI can not only help assess image-defined risk factors but can also quantitatively reflect the biologic features of neuroblastoma in a noninvasive manner. Therefore, compared with anatomic imaging, these emerging quantitative MRI technologies are expected to provide more imaging biomarkers for the management of neuroblastoma. This review article discusses the current applications of quantitative MRI technologies in evaluating childhood neuroblastoma. Keywords: Pediatrics, MR-Functional Imaging, Children, MRI, Neuroblastoma, Quantitative Imaging © RSNA, 2024.

The prognostic role of 18F-FDG PET/CT-based response evaluation in children with stage 4 neuroblastoma

OBJECTIVES

To evaluate the association between metabolic response on 18F-FDG PET/CT and long-term survival in children with neuroblastoma (NB).

METHODS

A total of 39 consecutive children with newly diagnosed stage 4 NB undergoing both 18F-FDG PET/CT imaging at baseline and after chemotherapy were retrospectively analyzed. The associations between metabolic parameters, including SUVmax of the lesion with the most intense 18F-FDG uptake at baseline (SUVb), after chemotherapy (SUVe), and the percentage change between SUVb and SUVe, and long-term survival were evaluated.

RESULTS

With a median follow-up of 56 months, 22 patients who had achieved complete resolution on PET (no residual 18F-FDG uptake higher than the surrounding backgrounds) after chemotherapy had superior 5-year overall survival (OS) (73.6% vs. 39.0%, p = 0.044). SUVb > 6.9 indicated significantly poorer 5-year event-free survival (EFS) (12.5% vs. 59.3%, p = 0.005), as did SUVe > 1.2 (18.8% vs. 41.7%, p = 0.041). Children with SUVe > 1.2 had shorter 5-year OS (33.9% vs. 75.0%, p = 0.018). Multivariate analysis identified SUVe > 1.2 as an independent predictor for both EFS [hazard ratio (HR), 3.479, 95% CI, 1.381-8.761, p = 0.008] and OS (HR, 6.948, 95% CI, 1.663-29.025, p = 0.008), while SUVb > 6.9 was a predictor for EFS (HR, 2.889, 95% CI, 1.064-7.842, p = 0.037). Among 11 children with both SUVb > 6.9 and SUVe > 1.2, all experienced disease progression or relapse within 2 years since diagnosis.

CONCLUSION

18F-FDG PET/CT could be of useful to evaluate treatment response in children with stage 4 NB.

CLINICAL RELEVANCE STATEMENT

18F-FDG PET/CT after chemotherapy exhibits prognostic significance in neuroblastoma and holds potential as an alternative imaging modality for response evaluation, especially in cases with metaiodobenzylguanidine-nonavid or persistent avid disease.

KEY POINTS

The prognostic value of chemotherapy response on 18F-FDG PET/CT in advanced neuroblastoma is unknown. Higher 18F-FDG uptake after chemotherapy was associated with worse long-term event-free survival and overall survival. 18F-FDG PET/CT after chemotherapy holds prognostic significance in children with stage 4 neuroblastoma.

Management of Busulfan-Induced Lung Injury in Pediatric Patients with High-Risk Neuroblastoma

Background/Objectives: Integrating the cytotoxic drug busulfan into a high-dose chemotherapy regimen prior to autologous hematopoietic stem cell rescue in patients with high-risk neuroblastoma has improved the survival of children battling this deadly disease. Busulfan-induced toxicities can, however, be severe. Here, we describe the diagnosis and successful treatment of acute pulmonary injury by total-body-weight-adjusted busulfan therapy in two children with high-risk neuroblastoma. Case series: Patient 1 developed life-threatening biphasic acute respiratory failure on days +60 and +100 after busulfan therapy, requiring intubation and invasive mechanical ventilation. Despite intensive anti-inflammatory and immunomodulatory therapy, including systemic corticosteroids, topical inhalation regimens, azithromycin, nintedanib and extracorporal photopheresis, patient 1 required extended intensive care measures and non-invasive respiratory support for a total of 20 months. High-resolution computed tomography showed diffuse intra-alveolar and interstitial patterns. Patient 2 developed partial respiratory failure with insufficient oxygen saturation and dyspnea on day +52 after busulfan therapy. Symptoms were resolved after 6 months of systemic corticosteroids, topical inhalation regimens and azithromycin. High-resolution computed tomography showed atypical pneumonic changes with ground-glass opacities. While both patients fully recovered without evidence of pulmonary fibrosis, cancer therapy had to be paused and then modified until full recovery from busulfan-induced lung injury. Conclusions: Busulfan-induced lung injury requires prompt diagnosis and intervention. Symptoms and signs are nonspecific and difficult to differentiate from other causes. Therapeutic busulfan drug level monitoring and the identification of patients at risk for drug overdosing through promoter polymorphisms in the glutathione S-transferase alpha 1 gene encoding the main enzyme in busulfan metabolism are expected to reduce the risk of busulfan-induced toxicities.

Tumoricidal Activity and Side Effects of Radiolabeled Anti-NCAM [131I]-Iodine-ERIC1 in Neuroblastoma-Bearing Mice

Preliminary studies on a radioactive antibody against the neural cell adhesion molecule (NCAM) demonstrated a significant accumulation of [131I]I-ERIC1 in neuroblastoma tumor cells in mice. This study aims to validate the therapeutic efficacy and potential adverse effects of these radioactive immunoconjugates (RICs) in neuroblastoma-bearing mice. To determine the highest tolerated dose, healthy SCID mice received 1 to 22 MBq of [131I]I-ERIC1, with the survival time measured. Tumor response was evaluated by administering 0.8 to 22 MBq of [131I]I-ERIC1 to neuroblastoma-bearing mice and assessing tumor size and systemic toxicity through body weight, blood counts, and survival. It was observed that doses up to approximately 3 MBq per animal (150 MBq/kg) were well tolerated, whereas higher doses resulted in systemic toxicity and death. The neuroblastomas exhibited a dose-dependent response, with optimal therapeutic efficacy achieved at 1.8-2.5 MBq per animal (90-125 MBq/kg), significantly extending survival by a factor of five. The antibody ERIC1 is a promising vehicle for the transport of beta emitters into NCAM-positive tumor tissue. An optimal dosage of the [131I]I-ERIC1 antibody can be established with a balance of tumor-static effects and adverse effects, resulting in a marked extension of survival time.

Heterogeneous SSTR2 target expression and a novel KIAA1549::BRAF fusion clone in a progressive metastatic lesion following 177Lutetium-DOTATATE molecular radiotherapy in neuroblastoma: a case report

In this case report, we present the treatment outcomes of the first patient enrolled in the LuDO-N trial. The patient is a 21-month-old girl diagnosed with high-risk neuroblastoma (NB) and widespread skeletal metastasis. The patient initially underwent first-line therapy according to SIOPEN HRNBL-1 but was switched to second-line treatments due to disease progression, and she was finally screened for enrollment in the LuDO-N trial due to refractory disease. Upon enrollment, the patient received two rounds of the radiolabeled somatostatin analogue lutetium-177 octreotate (177Lu-DOTATATE), which was well tolerated. A dosimetry analysis revealed a heterogeneous uptake across tumor lesions, resulting in a significant absorbed dose of 54 Gy in the primary tumor, but only 2 Gy at one of the metastatic sites in the distal femur. While the initial treatment response showed disease stabilization, the distal femoral metastasis continued to progress, leading to the eventual death of the patient. A tissue analysis of the biopsies collected throughout the course of the disease revealed heterogeneous drug target expression of somatostatin receptor 2 (SSTR2) across and within tumor lesions. Furthermore, genomic profiling revealed a novel KIAA1549::BRAF fusion oncogene amplification in the distal femoral metastasis at recurrence that might be related with resistance to radiation, possibly through the downregulation of SSTR2. This case report demonstrates a mixed response to molecular radiotherapy (MRT) with 177Lu-DOTATATE. The observed variation in SSTR2 expression between tumor lesions suggests that heterogeneous target expression may have been the reason for treatment failure in this patient's case. Further investigation within the LuDO-N trial will give a more comprehensive understanding of the correlation between SSTR2 expression levels and treatment outcomes, which will be important to advance treatment strategies based on MRT for children with high-risk NB.

Phase I study of safety and efficacy of allogeneic natural killer cell therapy in relapsed/refractory neuroblastomas post autologous hematopoietic stem cell transplantation

Despite low incidence, neuroblastoma, an immunologically cold tumor, is the most common extracranial solid neoplasm in pediatrics. In relapsed/refractory cases, the benefits of autologous hematopoietic stem cell transplantation (auto-HSCT) and other therapies are limited. Natural killer (NK) cells apply cytotoxicity against tumor cells independently of antigen-presenting cells and the adaptive immune system. The primary endpoint of this trial was to assess the safety of the injection of allogenic, ex vivo-expanded and primed NK cells in relapsed/refractory neuroblastoma patients after auto-HSCT. The secondary endpoint included the efficacy of this intervention in controlling tumors. NK cells were isolated and primed ex vivo (by adding interleukin [IL]-2, IL-15, and IL-21) in a GMP-compliant CliniMACS system and administered to four patients with relapsed/refractory MYCN-positive neuroblastoma. NK cell injections (1 and 5 × 107 cells/kg in the first and second injections, respectively) were safe, and no acute or sub-acute adverse events were observed. During the follow-up period, one complete response (CR) and one partial response (PR) were observed, while two cases exhibited progressive disease (PD). In follow-up evaluations, two died due to disease progression, including the case with a PR. The patient with CR had regular growth at the 31-month follow-up, and another patient with PD is still alive and receiving chemotherapies 20 months after therapy. This therapy is an appealing and feasible approach for managing refractory neuroblastomas post-HSCT. Further studies are needed to explore its efficacy with higher doses and more frequent administrations for high-risk neuroblastomas and other immunologically cold tumors.Trial registration number: irct.behdasht.gov.ir (Iranian Registry of Clinical Trials, No. IRCT20201202049568N1).

Response-adapted consolidation therapy strategy for patients with metastatic high-risk neuroblastoma: Results of the SMC NB-2014 study

BACKGROUND

Tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) and incorporation of 131I-metaiodobenzylguanidine (131I-MIBG) treatment have shown positive outcomes in high-risk neuroblastoma. However, more optimized treatment strategies are still needed.

PROCEDURE

The NB-2014 study was a nonrandomized, prospective trial that examined survival outcomes in metastatic high-risk neuroblastoma patients using response-adapted consolidation therapy. We used post-induction residual 123I-MIBG status at metastatic sites as a treatment response marker. Patients achieving complete resolution of MIBG uptake at metastatic sites underwent a reduced first HDCT/auto-SCT with a 20% dose reduction in HDCT. After the first HDCT/auto-SCT, patients with remaining MIBG uptake received dose-escalated (18 mCi/kg) 131I-MIBG treatment. In contrast, those with complete resolution of MIBG at metastatic sites received a standard dose (12 mCi/kg) of 131I-MIBG. We compared survival and toxicity outcomes with a historical control group from the NB-2009.

RESULTS

Of 65 patients treated, 63% achieved complete resolution of MIBG uptake at metastatic sites following induction chemotherapy, while 29% of patients still had MIBG uptake at metastatic sites after the first HDCT/auto-SCT. The 3-year event-free survival (EFS) and overall survival (OS) rates were 68.2% ± 6.0% and 86.5% ± 4.5%, respectively. Compared to NB-2009, EFS was similar (p = .855); however, NB-2014 had a higher OS (p = .031), a lower cumulative incidence of treatment-related mortality (p = .036), and fewer acute and late toxicities.

CONCLUSIONS

Our results suggest that response-adaptive consolidation therapy based on chemotherapy response at metastatic sites facilitates better treatment tailoring, and appears promising for patients with metastatic high-risk neuroblastoma.

Long-Lasting Response to Lorlatinib in Patients with ALK-Driven Relapsed or Refractory Neuroblastoma Monitored with Circulating Tumor DNA Analysis

Patients with anaplastic lymphoma kinase (ALK)-driven neuroblastoma may respond to tyrosine kinase inhibitors, but resistance to treatment occurs and methods currently used for detection of residual disease have limited sensitivity. Here, we present a national unselected cohort of five patients with relapsed or refractory ALK-driven neuroblastoma treated with lorlatinib as monotherapy and test the potential of targeted circulating tumor DNA (ctDNA) analysis as a guide for treatment decisions in these patients. We developed a sequencing panel for ultrasensitive detection of ALK mutations associated with neuroblastoma or resistance to tyrosine kinase inhibitors and used it for ctDNA analysis in 83 plasma samples collected longitudinally from the four patients who harbored somatic ALK mutations. All four patients with ALK p.R1275Q experienced major responses and were alive 35 to 61 months after starting lorlatinib. A fifth patient with ALK p.F1174L initially had a partial response but relapsed after 10 months of treatment. In all cases, ctDNA was detected at the start of lorlatinib single-agent treatment and declined gradually, correlating with clinical responses. In the two patients exhibiting relapse, ctDNA increased 9 and 3 months, respectively, before clinical detection of disease progression. In one patient harboring HRAS p.Q61L in the relapsed tumor, retrospective ctDNA analysis showed that the mutation appeared de novo after 8 months of lorlatinib treatment. We conclude that some patients with relapsed or refractory high-risk neuroblastoma show durable responses to lorlatinib as monotherapy, and targeted ctDNA analysis is effective for evaluation of treatment and early detection of relapse in ALK-driven neuroblastoma.

SIGNIFICANCE

We present five patients with ALK-driven relapsed or refractory neuroblastoma treated with lorlatinib as monotherapy. All patients responded to treatment, and four of them were alive after 3 to 5 years of follow-up. We performed longitudinal ctDNA analysis with ultra-deep sequencing of the ALK tyrosine kinase domain. We conclude that ctDNA analysis may guide treatment decisions in ALK-driven neuroblastoma, also when the disease is undetectable using standard clinical methods.

Phase 1 study of NEDD8 activating enzyme inhibitor pevonedistat in combination with chemotherapy in pediatric patients with recurrent or refractory solid tumors (ADVL1615)

PURPOSE

The objective of this study was to determine the recommended Phase 2 dose (RP2D) of pevonedistat, a first in class inhibitor of NEDD8 activating enzyme, in combination with irinotecan (IRN) and temozolomide (TMZ) in children with cancer.

METHODS

This Phase 1 study used a rolling 6 design to evaluate escalating doses of pevonedistat in combination with standard doses of IRN and TMZ in pediatric patients with recurrent/refractory solid or CNS tumors. During cycle 1, pevonedistat was administered intravenously on days 1, 8, 10, and 12, with IRN (IV, 50 mg/m2) and TMZ (orally, 100 mg/m2), on days 8-12 of a 28-day cycle. In subsequent cycles, pevonedistat was administered on days 1, 3, and 5, with IRN/TMZ on days 1-5 of a 21-day cycle.

RESULTS

Thirty patients enrolled; all were eligible and evaluable for toxicity. Six patients each enrolled on pevonedistat dose levels (DL) 1 (15 mg/m2), 2 (20 mg/m2), 3 (25 mg/m2) and 4 (35 mg/m2) as well as an expanded pharmacokinetic (PK) cohort at DL4. The maximum tolerated dose (MTD) was not exceeded. 2/12 (17 %) patients treated at the RP2D (35 mg/m2) experienced a cycle 1 dose limiting toxicity (DLT). IRN is unlikely to affect the pharmacokinetics of pevonedistat. Two patients had a partial response and 6 patients had prolonged stable disease (> 6 cycles).

CONCLUSIONS

Pevonedistat in combination with IRN/TMZ is well tolerated in children with solid or CNS tumors. The RP2D of pevonedistat is 35 mg/m2 on days 1, 3, 5 in combination with IRN/TMZ.

Sequential Analysis of cfDNA Reveals Clonal Evolution in Patients with Neuroblastoma Receiving ALK-Targeted Therapy

PURPOSE

The study of cell-free DNA (cfDNA) enables sequential analysis of tumor cell-specific genetic alterations in patients with neuroblastoma.

EXPERIMENTAL DESIGN

Eighteen patients with relapsing neuroblastoma having received lorlatinib, a third-generation ALK inhibitor, were identified (SACHA national registry and/or in the institution). cfDNA was analyzed at relapse for nine patients and sequentially for five patients (blood/bone marrow plasma) by performing whole-genome sequencing library construction followed by ALK-targeted ddPCR of the hotspot mutations [F1174L, R1275Q, and I1170N; variant allele fraction (VAF) detection limit 0.1%] and whole-exome sequencing (WES) to evaluate disease burden and clonal evolution, following comparison with tumor/germline WES.

RESULTS

Overall response rate to lorlatinib was 33% (CI, 13%-59%), with response observed in 6/10 cases without versus 0/8 cases with MYCN amplification (MNA). ALK VAFs correlated with the overall clinical disease status, with a VAF < 0.1% in clinical remission, versus higher VAFs (>30%) at progression. Importantly, sequential ALK ddPCR detected relapse earlier than clinical imaging. cfDNA WES revealed new SNVs, not seen in the primary tumor, in all instances of disease progression after lorlatinib treatment, indicating clonal evolution, including alterations in genes linked to tumor aggressivity (TP53) or novel targets (EGFR). Gene pathway analysis revealed an enrichment for genes targeting cell differentiation in emerging clones, and cell adhesion in persistent clones. Evidence of clonal hematopoiesis could be observed in follow-up samples.

CONCLUSIONS

We demonstrate the clinical utility of combining ALK cfDNA ddPCR for disease monitoring and cfDNA WES for the study of clonal evolution and resistance mechanisms in patients with neuroblastoma receiving ALK-targeted therapy.

Application of the FISH method and high-density SNP arrays to assess genetic changes in neuroblastoma-research by one institute

Neuroblastoma is the most common extracranial solid tumor in children. Amplification of the MYCN gene has been observed in approximately 20%-30% of tumors. It is strongly correlated with advanced-stage disease, rapid tumor progression, resistance to chemotherapy and poor outcomes independent of patient age and stage of advanced disease. MYCN amplification identifies high-risk patients. To assess neuroblastoma tumors with MYCN amplification we used paraffin-embedded tissue sections in 57 patients and intraoperative tumor imprints in 10 patients by fluorescence in situ hybridization (FISH). Positive results for MYCN amplification have been observed in twelve patients' paraffin-embedded tissue sections and in three patients' intraoperative tumor imprints, which represents 22.4% of all patients tested in the analysis. Fluorescence in situ hybridization is a highly sensitive and useful technique for detecting MYCN amplification on paraffin-embedded tissue sections of neuroblastoma tumors and intraoperative tumor imprints thus facilitating therapeutic decisions based on the presence or absence of this important biologic marker. The presence of structural changes, regardless of MYCN gene amplification status, influences the clinical behavior of neuroblastoma. High-Density SNP Arrays have emerged as the perfect tools for detecting these changes due to their exceptional accuracy, sensitivity and ability to analyze copy number and allele information. Consequently, they are proven to be highly valuable in the genomic diagnosis of immature neuroectodermal tumors.

Irinotecan and temozolomide in combination with dasatinib and rapamycin versus irinotecan and temozolomide for patients with relapsed or refractory neuroblastoma (RIST-rNB-2011): a multicentre, open-label, randomised, controlled, phase 2 trial

BACKGROUND

Neuroblastoma is the most common extracranial solid tumour in children. Relapsed or refractory neuroblastoma is associated with a poor outcome. We assessed the combination of irinotecan-temozolomide and dasatinib-rapamycin (RIST) in patients with relapsed or refractory neuroblastoma.

METHODS

The multicentre, open-label, randomised, controlled, phase 2, RIST-rNB-2011 trial recruited from 40 paediatric oncology centres in Germany and Austria. Patients aged 1-25 years with high-risk relapsed (defined as recurrence of all stage IV and MYCN amplification stages, after response to treatment) or refractory (progressive disease during primary treatment) neuroblastoma, with Lansky and Karnofsky performance status at least 50%, were assigned (1:1) to RIST (RIST group) or irinotecan-temozolomide (control group) by block randomisation, stratified by MYCN status. We compared RIST (oral rapamycin [loading 3 mg/m2 on day 1, maintenance 1 mg/m2 on days 2-4] and oral dasatinib [2 mg/kg per day] for 4 days with 3 days off, followed by intravenous irinotecan [50 mg/m2 per day] and oral temozolomide [150 mg/m2 per day] for 5 days with 2 days off; one course each of rapamycin-dasatinib and irinotecan-temozolomide for four cycles over 8 weeks, then two courses of rapamycin-dasatinib followed by one course of irinotecan-temozolomide for 12 weeks) with irinotecan-temozolomide alone (with identical dosing as experimental group). The primary endpoint of progression-free survival was analysed in all eligible patients who received at least one course of therapy. The safety population consisted of all patients who received at least one course of therapy and had at least one post-baseline safety assessment. This trial is registered at ClinicalTrials.gov, NCT01467986, and is closed to accrual.

FINDINGS

Between Aug 26, 2013, and Sept 21, 2020, 129 patients were randomly assigned to the RIST group (n=63) or control group (n=66). Median age was 5·4 years (IQR 3·7-8·1). 124 patients (78 [63%] male and 46 [37%] female) were included in the efficacy analysis. At a median follow-up of 72 months (IQR 31-88), the median progression-free survival was 11 months (95% CI 7-17) in the RIST group and 5 months (2-8) in the control group (hazard ratio 0·62, one-sided 90% CI 0·81; p=0·019). Median progression-free survival in patients with amplified MYCN (n=48) was 6 months (95% CI 4-24) in the RIST group versus 2 months (2-5) in the control group (HR 0·45 [95% CI 0·24-0·84], p=0·012); median progression-free survival in patients without amplified MYCN (n=76) was 14 months (95% CI 9-7) in the RIST group versus 8 months (4-15) in the control group (HR 0·84 [95% CI 0·51-1·38], p=0·49). The most common grade 3 or worse adverse events were neutropenia (54 [81%] of 67 patients given RIST vs 49 [82%] of 60 patients given control), thrombocytopenia (45 [67%] vs 41 [68%]), and anaemia (39 [58%] vs 38 [63%]). Nine serious treatment-related adverse events were reported (five patients given control and four patients given RIST). There were no treatment-related deaths in the control group and one in the RIST group (multiorgan failure).

INTERPRETATION

RIST-rNB-2011 demonstrated that targeting of MYCN-amplified relapsed or refractory neuroblastoma with a pathway-directed metronomic combination of a multkinase inhibitor and an mTOR inhibitor can improve progression-free survival and overall survival. This exclusive efficacy in MYCN-amplified, relapsed neuroblastoma warrants further investigation in the first-line setting.

FUNDING

Deutsche Krebshilfe.

Staging and Restaging Pediatric Abdominal and Pelvic Tumors: A Practical Guide

The most common abdominal malignancies diagnosed in the pediatric population include neuroblastoma, Wilms tumor, hepatoblastoma, lymphoma, germ cell tumor, and rhabdomyosarcoma. There are distinctive imaging findings and patterns of spread for each of these tumors that radiologists must know for diagnosis and staging and for monitoring the patient's response to treatment. The multidisciplinary treatment group that includes oncologists, surgeons, and radiation oncologists relies heavily on imaging evaluation to identify the best treatment course and prognostication of imaging findings, such as the image-defined risk factors for neuroblastomas, the PRETreatment EXtent of Disease staging system for hepatoblastoma, and the Ann Arbor staging system for lymphomas. It is imperative for radiologists to be able to correctly indicate the best imaging methods for diagnosis, staging, and restaging of each of these most prevalent tumors to avoid inconclusive or unnecessary examinations. The authors review in a practical manner the most updated key points in diagnosing and staging disease and assessing response to treatment of the most common pediatric abdominal tumors. ©RSNA, 2024 Supplemental material is available for this article.

Development and validation of a novel nomogram for predicting overall survival patients with neuroblastoma

PURPOSE

The aim of this study was to develop a nomogram specially for predicting overall survival (OS) for Chinese patients with neuroblastoma (NB).

METHODS

Patients with pathologically confirmed NB who were newly diagnosed and received treatments at our hospital from October 2013 to October 2021 were retrospectively reviewed. The nomogram for OS were built based on Cox regression analysis. The validation of the prognostic model was evaluated by concordance index (C-index), calibration curves, and decision curve analyses (DCAs).

RESULTS

A total of 254 patients with NB were included in this study. They were randomly divided into a training cohort (n = 178) and a validation cohort (n = 76) at a ratio of 7:3. Multivariate analyses revealed that prognostic variables significantly related to the OS were age at diagnosis, bone metastasis, hepatic metastasis, INSS stage, MYCN status and DNA ploidy. The nomogram was constructed based on above 6 factors. The C-index values of the nomogram for predicting 3-year and 5-year OS were 0.926 and 0.964, respectively. The calibration curves of the nomogram showed good consistency between nomogram prediction and actual survival. The DCAs showed great clinical usefulness of the nomograms. Furthermore, patients with low-risk identified by our nomogram had much higher OS than those with high-risk (p < 0.001).

CONCLUSION

The nomogram we constructed exhibited good predictive performance and could be used to assist clinicians in their decision-making process.

Long Prime-Boost Interval and Heightened Anti-GD2 Antibody Response to Carbohydrate Cancer Vaccine

The carbohydrate ganglioside GD2/GD3 cancer vaccine adjuvanted by β-glucan stimulates anti-GD2 IgG1 antibodies that strongly correlate with improved progression-free survival (PFS) and overall survival (OS) among patients with high-risk neuroblastoma. Thirty-two patients who relapsed on the vaccine (first enrollment) were re-treated on the same vaccine protocol (re-enrollment). Titers during the first enrollment peaked by week 32 at 751 ± 270 ng/mL, which plateaued despite vaccine boosts at 1.2-4.5 month intervals. After a median wash-out interval of 16.1 months from the last vaccine dose during the first enrollment to the first vaccine dose during re-enrollment, the anti-GD2 IgG1 antibody rose to a peak of 4066 ± 813 ng/mL by week 3 following re-enrollment (p < 0.0001 by the Wilcoxon matched-pairs signed-rank test). Yet, these peaks dropped sharply and continually despite repeated boosts at 1.2-4.5 month intervals, before leveling off by week 20 to the first enrollment peak levels. Despite higher antibody titers, patients experienced no pain or neuropathic side effects, which were typically associated with immunotherapy using monoclonal anti-GD2 antibodies. By the Kaplan-Meier method, PFS was estimated to be 51%, and OS was 81%. The association between IgG1 titer during re-enrollment and β-glucan receptor dectin-1 SNP rs3901533 was significant (p = 0.01). A longer prime-boost interval could significantly improve antibody responses in patients treated with ganglioside conjugate cancer vaccines.

Whole genome and transcriptome integrated analyses guide clinical care of pediatric poor prognosis cancers

The role for routine whole genome and transcriptome analysis (WGTA) for poor prognosis pediatric cancers remains undetermined. Here, we characterize somatic mutations, structural rearrangements, copy number variants, gene expression, immuno-profiles and germline cancer predisposition variants in children and adolescents with relapsed, refractory or poor prognosis malignancies who underwent somatic WGTA and matched germline sequencing. Seventy-nine participants with a median age at enrollment of 8.8 y (range 6 months to 21.2 y) are included. Germline pathogenic/likely pathogenic variants are identified in 12% of participants, of which 60% were not known prior. Therapeutically actionable variants are identified by targeted gene report and whole genome in 32% and 62% of participants, respectively, and increase to 96% after integrating transcriptome analyses. Thirty-two molecularly informed therapies are pursued in 28 participants with 54% achieving a clinical benefit rate; objective response or stable disease ≥6 months. Integrated WGTA identifies therapeutically actionable variants in almost all tumors and are directly translatable to clinical care of children with poor prognosis cancers.

Chemo-immunotherapy with dinutuximab beta in patients with relapsed/progressive high-risk neuroblastoma: does chemotherapy backbone matter?

BACKGROUND

Addition of anti-GD2 antibodies to temozolomide-based chemotherapy has demonstrated increased antitumor activity and progression-free survival in patients with relapsed/progressive high-risk neuroblastoma. However, chemo-immunotherapy is not yet approved for this indication. This study presents the chemo-immunotherapy experience in patients with relapsed/progressive high-risk neuroblastoma treated within the off-label use program of the Neuroblastoma Committee of the French Society of Pediatric Oncology (SFCE).

METHODS

Dinutuximab beta (dB) was administered alongside temozolomide-topotecan (TOTEM) or temozolomide-irinotecan (TEMIRI) at first disease relapse/progression or topotecan-cyclophosphamide (TopoCyclo) at further relapse/progression. Real-world data on demographics, treatment, antitumor activity and safety was collected from all patients after inclusion in SACHA-France (NCT04477681), a prospective national registry, which documents safety and efficacy data on innovative anticancer therapies prescribed to patients ≤ 25 years old as compassionate or off-label use.

RESULTS

Between February 2021 and July 2023, 39 patients with confirmed relapsed/progressive high-risk neuroblastoma (median age 6 years, range 1-24) were treated with dB+TopoCyclo (n = 24) or dB+TOTEM/TEMIRI (n = 15) across 17 centers. In total, 163 chemo-immunotherapy cycles were administered, main toxicities were mild or moderate, with higher incidence of hematological adverse drug reactions with dB+TopoCyclo than dB+TOTEM/TEMIRI. Objective response rate was 42% for dB+TopoCyclo (CI95% 22-63%) and 40% for dB+TOTEM/TEMIRI (CI95% 16-68%).

CONCLUSION

Similar objective response rates for dB+TopoCyclo and dB+TOTEM/TEMIRI in patients with relapsed/progressive high-risk neuroblastoma emphasize the importance of chemo-immunotherapy, irrespective of the chemotherapy backbone.

Management of High-Risk Neuroblastoma with Soft-Tissue-Only Disease in the Era of Anti-GD2 Immunotherapy

Neuroblastoma presents with two patterns of disease: locoregional or systemic. The poor prognostic risk factors of locoregional neuroblastoma (LR-NB) include age, MYCN or MDM2-CDK4 amplification, 11q, histology, diploidy with ALK or TERT mutations, and ATRX aberrations. Anti-GD2 immunotherapy has significantly improved the outcome of high-risk (HR) NB and is mostly effective against osteomedullary minimal residual disease (MRD), but less so against soft tissue disease. The question is whether adding anti-GD2 monoclonal antibodies (mAbs) benefits patients with HR-NB compounded by only soft tissue. We reviewed 31 patients treated at SJD for HR-NB with no osteomedullary involvement at diagnosis. All tumors had molecular genetic features of HR-NB. The outcome after first-line treatment showed 25 (80.6%) patients achieving CR. Thirteen patients remain in continued CR, median follow-up 3.9 years. We analyzed whether adding anti-GD2 immunotherapy to first-line treatment had any prognostic significance. The EFS analysis using Cox models showed a HR of 0.20, p = 0.0054, and an 80% decrease in the risk of relapse in patients treated with anti-GD2 immunotherapy in the first line. Neither EFS nor OS were significantly different by CR status after first-line treatment. In conclusion, adding treatment with anti-GD2 mAbs at the stage of MRD helps prevent relapse that unequivocally portends poor survival.

GM-CSF, G-CSF or no cytokine therapy with anti-GD2 immunotherapy for high-risk neuroblastoma

Colony-stimulating factors have been shown to improve anti-disialoganglioside 2 (anti-GD2) monoclonal antibody response in high-risk neuroblastoma by enhancing antibody-dependent cell-mediated cytotoxicity (ADCC). A substantial amount of research has focused on recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) as an adjuvant to anti-GD2 monoclonal antibodies. There may be a disparity in care among patients as access to GM-CSF therapy and anti-GD2 monoclonal antibodies is not uniform. Only select countries have approved these agents for use, and even with regulatory approvals, access to these agents can be complex and cost prohibitive. This comprehensive review summarizes clinical data regarding efficacy and safety of GM-CSF, recombinant human granulocyte colony-stimulating factor (G-CSF) or no cytokine in combination with anti-GD2 monoclonal antibodies (ie, dinutuximab, dinutuximab beta or naxitamab) for immunotherapy of patients with high-risk neuroblastoma. A substantial body of clinical data support the immunotherapy combination of anti-GD2 monoclonal antibodies and GM-CSF. In contrast, clinical data supporting the use of G-CSF are limited. No formal comparison between GM-CSF, G-CSF and no cytokine has been identified. The treatment of high-risk neuroblastoma with anti-GD2 therapy plus GM-CSF is well established. Suboptimal efficacy outcomes with G-CSF raise concerns about its suitability as an alternative to GM-CSF as an adjuvant in immunotherapy for patients with high-risk neuroblastoma. While programs exist to facilitate obtaining GM-CSF and anti-GD2 monoclonal antibodies in regions where they are not commercially available, continued work is needed to ensure equitable therapeutic options are available globally.

Bilateral adrenal neuroblastoma: peculiar pattern of a rare pediatric presentation

BACKGROUND

Bilateral suprarenal neuroblastoma (BSN) is a rare presentation. Few previously published literature showed BSN patients to have favorable pattern and prognosis. This study aim was to evaluate clinical and biological features in relation to outcome of Egyptian patients with BSN.

METHODS

Included patients were diagnosed from 2007 to 2017, retrospectively. Tissue biopsy, imaging and bone marrow were evaluated at presentation. Clinical, demographic, biological variables and risk group were determined and analyzed in relation to overall (OS) and event-free-survival (EFS).

RESULTS

BSN patients (n = 33) represented 2% of hospital patients with neuroblastoma during the 10-year study period, 17 were males and 16 were females. Twenty-four patients (72.7%) were infants, and 9 patients (27.3%) were above 1 year of age (range: 1 month to 3 years). Metachronous disease was present in only one patient. Amplified MYCN was found in 10 patients. Initially, most patients (n = 25) had distant metastasis, 6 had stage 3 versus 2 stage 2. Fifteen were high risk (HR), 15 intermediate (IR), 1 low risk (LR) and 2 were undetermined due to inadequate tissue biopsy. Three-year OS for HR and IR patients were 40.5% and 83.9% versus 23.2% and 56.6% EFS; respectively.

CONCLUSION

BSN treatment is similar to unilateral disease. A more conservative surgical approach with adrenal tissue preservation on less extensive side should be considered. Biological variables and extent of disease are amongst the most important prognostic determinants. Future studies are warranted to further address the biologic profiling of BSN and highlight prognostic significance of size difference between both adrenal sides.

Bevacizumab, Irinotecan, or Topotecan Added to Temozolomide for Children With Relapsed and Refractory Neuroblastoma: Results of the ITCC-SIOPEN BEACON-Neuroblastoma Trial

PURPOSE

Outcomes for children with relapsed and refractory high-risk neuroblastoma (RR-HRNB) remain dismal. The BEACON Neuroblastoma trial (EudraCT 2012-000072-42) evaluated three backbone chemotherapy regimens and the addition of the antiangiogenic agent bevacizumab (B).

MATERIALS AND METHODS

Patients age 1-21 years with RR-HRNB with adequate organ function and performance status were randomly assigned in a 3 × 2 factorial design to temozolomide (T), irinotecan-temozolomide (IT), or topotecan-temozolomide (TTo) with or without B. The primary end point was best overall response (complete or partial) rate (ORR) during the first six courses, by RECIST or International Neuroblastoma Response Criteria for patients with measurable or evaluable disease, respectively. Safety, progression-free survival (PFS), and overall survival (OS) time were secondary end points.

RESULTS

One hundred sixty patients with RR-HRNB were included. For B random assignment (n = 160), the ORR was 26% (95% CI, 17 to 37) with B and 18% (95% CI, 10 to 28) without B (risk ratio [RR], 1.52 [95% CI, 0.83 to 2.77]; P = .17). Adjusted hazard ratio for PFS and OS were 0.89 (95% CI, 0.63 to 1.27) and 1.01 (95% CI, 0.70 to 1.45), respectively. For irinotecan ([I]; n = 121) and topotecan (n = 60) random assignments, RRs for ORR were 0.94 and 1.22, respectively. A potential interaction between I and B was identified. For patients in the bevacizumab-irinotecan-temozolomide (BIT) arm, the ORR was 23% (95% CI, 10 to 42), and the 1-year PFS estimate was 0.67 (95% CI, 0.47 to 0.80).

CONCLUSION

The addition of B met protocol-defined success criteria for ORR and appeared to improve PFS. Within this phase II trial, BIT showed signals of antitumor activity with acceptable tolerability. Future trials will confirm these results in the chemoimmunotherapy era.

Targeting refractory/recurrent neuroblastoma and osteosarcoma with anti-CD3×anti-GD2 bispecific antibody armed T cells

BACKGROUND

The survival benefit observed in children with neuroblastoma (NB) and minimal residual disease who received treatment with anti-GD2 monoclonal antibodies prompted our investigation into the safety and potential clinical benefits of anti-CD3×anti-GD2 bispecific antibody (GD2Bi) armed T cells (GD2BATs). Preclinical studies demonstrated the high cytotoxicity of GD2BATs against GD2+cell lines, leading to the initiation of a phase I/II study in recurrent/refractory patients.

METHODS

The 3+3 dose escalation phase I study (NCT02173093) encompassed nine evaluable patients with NB (n=5), osteosarcoma (n=3), and desmoplastic small round cell tumors (n=1). Patients received twice-weekly infusions of GD2BATs at 40, 80, or 160×106 GD2BATs/kg/infusion complemented by daily interleukin-2 (300,000 IU/m2) and twice-weekly granulocyte macrophage colony-stimulating factor (250 µg/m2). The phase II segment focused on patients with NB at the dose 3 level of 160×106 GD2BATs/kg/infusion.

RESULTS

Of the 12 patients enrolled, 9 completed therapy in phase I with no dose-limiting toxicities. Mild and manageable cytokine release syndrome occurred in all patients, presenting as grade 2-3 fevers/chills, headaches, and occasional hypotension up to 72 hours after GD2BAT infusions. GD2-antibody-associated pain was minimal. Median overall survival (OS) for phase I and the limited phase II was 18.0 and 31.2 months, respectively, with a combined OS of 21.1 months. A phase I NB patient had a complete bone marrow response with overall stable disease. In phase II, 10 of 12 patients were evaluable: 1 achieved partial response, and 3 showed clinical benefit with prolonged stable disease. Over 50% of evaluable patients exhibited augmented immune responses to GD2+targets post-GD2BATs, as indicated by interferon-gamma (IFN-γ) EliSpots, Th1 cytokines, and/or chemokines.

CONCLUSIONS

This study demonstrated the safety of GD2BATs up to 160×106 cells/kg/infusion. Coupled with evidence of post-treatment endogenous immune responses, our findings support further investigation of GD2BATs in larger phase II clinical trials.

Phase I/II Study of the WEE1 Inhibitor Adavosertib (AZD1775) in Combination with Carboplatin in Children with Advanced Malignancies: Arm C of the AcSé-ESMART Trial

PURPOSE

AcSé-ESMART Arm C aimed to define the recommended dose and activity of the WEE1 inhibitor adavosertib in combination with carboplatin in children and young adults with molecularly enriched recurrent/refractory malignancies.

PATIENTS AND METHODS

Adavosertib was administered orally, twice every day on Days 1 to 3 and carboplatin intravenously on Day 1 of a 21-day cycle, starting at 100 mg/m2/dose and AUC 5, respectively. Patients were enriched for molecular alterations in cell cycle and/or homologous recombination (HR).

RESULTS

Twenty patients (median age: 14.0 years; range: 3.4-23.5) were included; 18 received 69 treatment cycles. Dose-limiting toxicities were prolonged grade 4 neutropenia and grade 3/4 thrombocytopenia requiring transfusions, leading to two de-escalations to adavosertib 75 mg/m2/dose and carboplatin AUC 4; no recommended phase II dose was defined. Main treatment-related toxicities were hematologic and gastrointestinal. Adavosertib exposure in children was equivalent to that in adults; both doses achieved the cell kill target. Overall response rate was 11% (95% confidence interval, 0.0-25.6) with partial responses in 2 patients with neuroblastoma. One patient with medulloblastoma experienced unconfirmed partial response and 5 patients had stable disease beyond four cycles. Seven of these eight patients with clinical benefit had alterations in HR, replication stress, and/or RAS pathway genes with or without TP53 alterations, whereas TP53 pathway alterations alone (8/10) or no relevant alterations (2/10) were present in the 10 patients without benefit.

CONCLUSIONS

Adavosertib-carboplatin combination exhibited significant hematologic toxicity. Activity signals and identified potential biomarkers suggest further studies with less hematotoxic DNA-damaging therapy in molecularly enriched pediatric cancers.

PARC: a phase I/II study evaluating the safety and activity of pegylated recombinant human arginase BCT-100 in relapsed/refractory cancers of children and young adults

Background

The survival for many children with relapsed/refractory cancers remains poor despite advances in therapies. Arginine metabolism plays a key role in the pathophysiology of a number of pediatric cancers. We report the first in child study of a recombinant human arginase, BCT-100, in children with relapsed/refractory hematological, solid or CNS cancers.

Procedure

PARC was a single arm, Phase I/II, international, open label study. BCT-100 was given intravenously over one hour at weekly intervals. The Phase I section utilized a modified 3 + 3 design where escalation/de-escalation was based on both the safety profile and the complete depletion of arginine (defined as adequate arginine depletion; AAD <8μM arginine in the blood after 4 doses of BCT-100). The Phase II section was designed to further evaluate the clinical activity of BCT-100 at the pediatric RP2D determined in the Phase I section, by recruitment of patients with pediatric cancers into 4 individual groups. A primary evaluation of response was conducted at eight weeks with patients continuing to receive treatment until disease progression or unacceptable toxicity.

Results

49 children were recruited globally. The Phase I cohort of the trial established the Recommended Phase II Dose of 1600U/kg iv weekly in children, matching that of adults. BCT-100 was very well tolerated. No responses defined as a CR, CRi or PR were seen in any cohort within the defined 8 week primary evaluation period. However a number of these relapsed/refractory patients experienced prolonged radiological SD.

Conclusion

Arginine depletion is a clinically safe and achievable strategy in children with cancer. The RP2D of BCT-100 in children with relapsed/refractory cancers is established at 1600U/kg intravenously weekly and can lead to sustained disease stability in this hard to treat population.

Clinical trial registration

EudraCT, 2017-002762-44; ISRCTN, 21727048; and ClinicalTrials.gov, NCT03455140.