Sequential analysis of cfDNA reveals clonal evolution in neuroblastoma patients receiving ALK targeted therapy.

PURPOSE: The study of cell free DNA (cfDNA) enables sequential analysis of tumor cell-specific genetic alterations in neuroblastoma patients. EXPERIMENTAL DESIGN: Eighteen patients with relapsing neuroblastoma having received Lorlatinib, a 3rd generation ALK inhibitor, were identified (SACHA national registry and/or in the institution). cfDNA was analyzed at relapse for 9 patients, and sequentially for 5 patients (blood/bone marrow plasma) by performing WGS library construction followed by ALK-targeted ddPCR of the hotspot mutations (F1174L, R1275Q, I1170N) (variant allele fraction (VAF) detection limit 0.1%) and 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. CONCLUSION: 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 neuroblastoma patients receiving ALK targeted therapy.

Long-term weight gain in children with craniopharyngioma.

OBJECTIVE: Adamantinomatous craniopharyngioma mainly affects children. Excessive weight gain is a major long-term complication. The primary objective of this study was to assess long-term weight changes in children treated for craniopharyngioma. The secondary objectives were to identify risk factors for excessive weight gain and to look for associations with hypothalamic damage by the tumour or treatment. DESIGN: Single-centre retrospective cohort study. METHOD: Children managed for craniopharyngioma at our centre between 1990 and 2019 were included. The body mass index (BMI) standard deviation scores (SDS) at baseline and at last follow-up were compared. Univariate and multivariate analyses were performed in order to identify variables associated with the long-term BMI-SDS variation. RESULTS: The 108 patients had a mean follow-up of 10.4 years. The mean BMI-SDS increase over time was 2.11 (P < .001) overall, 1.21 (P < .001) in the group without hypothalamic involvement by the tumour, and 1.95 (P < .001) in the group managed using intended hypothalamus-sparing surgery. The absence of hypothalamic involvement by the tumour or treatment was significantly associated with less weight gain (P = .046 and P < .01, respectively). After adjustment, factors associated with a BMI-SDS change greater than 2 were female sex (P = .023), tumour involving the hypothalamus (P = .04), and higher baseline BMI (P < .001). CONCLUSION: Clinically significant weight gain occurred in nearly all children treated for craniopharyngioma, including those whose hypothalamus was spared by the tumour and intentionally by treatment. However, hypothalamus integrity was associated with less weight gain. Despite hypothalamus-sparing strategies, hypothalamic obesity remains a major concern, indicating a need for novel treatment approaches.

From biology to personalized medicine: Recent knowledge in osteosarcoma.

High-grade osteosarcoma is the most common paediatric bone cancer. More than one third of patients relapse and die of osteosarcoma using current chemotherapeutic and surgical strategies. To improve outcomes in osteosarcoma, two crucial challenges need to be tackled: 1-the identification of hard-to-treat disease, ideally from diagnosis; 2- choosing the best combined or novel therapies to eradicate tumor cells which are resistant to current therapies leading to disease dissemination and metastasize as well as their favorable microenvironment. Genetic chaos, tumor complexity and heterogeneity render this task difficult. The development of new technologies like next generation sequencing has led to an improvement in osteosarcoma oncogenesis knownledge. This review summarizes recent biological and therapeutical advances in osteosarcoma, as well as the challenges that must be overcome in order to develop personalized medicine and new therapeutic strategies and ultimately improve patient survival.

Very long-term outcomes of pediatric patients treated for optic pathway gliomas: A longitudinal cohort study.

BACKGROUND: Optic pathway gliomas (OPG) represent 5% of childhood brain tumors. Successive relapses lead to multiple treatments exposing to late complications. METHODS: We included patients treated at Gustave Roussy (GR) between 01.1980 and 12.2015 for OPG, before 18 years-old and alive at 5 years from diagnosis. Mortality and physical health conditions data were extracted from medical data files and updated thanks to the GR long-term follow-up program and French national mortality registry for patients included in the French Childhood Cancer Survivor Study. RESULTS: We included 182 5y-OPG-childhood survivors in the analysis (sex-ratio M/F 0.8, 35% with NF1). With a median follow-up of 17.2y (range=5-41), we registered 82 relapses, 9 second malignancies and 15 deaths as first events after 5 years, resulting in 20-y conditional overall survival (C-OS) and late events-free survival (LEFS) of 79.9% (95%CI=71-86) and 43.5% (95%CI=36-51) respectively. NF1 (Hazard ratio HR=3, 95%CI=1.4-6.8), hypothalamic involvement (HR=3.2, 95%CI=1.4-7.3), and radiotherapy (HR=2.8, 95%CI=1.1-6.7) were significantly associated with C-OS in multivariable analyses. Ninety-five percent of 5y-OPG survivors suffered from any health condition, especially visual acuity "<1/10" (n=109), pituitary deficiency (n=106) and neurocognitive impairment (n=89). NF1 (HR 2.1) was associated with precocious puberty. With a median time post diagnosis of 4.2 years, 33 cerebrovascular events were observed in 21 patients. CONCLUSION: Late relapses, second malignancies and cerebrovascular diseases are severe late events resulting in premature mortality. Morbidity is high and needing after-cancer care to improve quality of life. Risk factors could be considered to better stratify long-term follow-up.

CNS erythroblastic sarcoma: a potential emerging pediatric tumor type characterized by NFIA::RUNX1T1/3 fusions.

Erythroblastic sarcoma (ES) (previously called chloroma or granulocytic sarcoma) are rare hematological neoplams characterized by the proliferation of myeloid blasts at extramedullary sites, and primarily involve the skin and soft tissue of middle-aged adults. ES may be concomitant with or secondary to myeloid neoplasms (mostly acute myeloid leukemia (AML)) or in isolated cases (de novo) without infiltration of the bone marrow by blasts. ES share cytogenetic and molecular abnormalities with AML, including RUNX1T1 fusions. Some of these alterations seem to be correlated with particular sites of involvement. Herein, we report an isolated erythroblastic sarcoma with NFIA::RUNX1T1 located in the central nervous system (CNS) of a 3-year-old boy. Recently, two pediatric cases of CNS MS with complete molecular characterization have been documented. Like the current case, they concerned infants (2 and 3 years-old) presenting a brain tumor (pineal involvement) with leptomeningeal dissemination. Both cases also harbored a NFIA::RUNX1T3 fusion. ES constitutes a diagnostic challenge for neuropathologists because it does not express differentiation markers such as CD45, and may express CD99 which could be confused with CNS Ewing sarcoma. CD43 is the earliest pan-hematopoietic marker and CD45 is not expressed by erythroid lineage cells. E-cadherin (also a marker of erythroid precursors) and CD117 (expressed on the surface of erythroid lineage cells) constitute other immunhistochemical hallmarks of ES. The prognosis of patients with ES is similar to that of other patients with AML but de novo forms seem to have a poorer prognosis, like the current case. To conclude, pediatric ES with NFIA::RUNX1T1/3 fusions seem to have a tropism for the CNS and thus constitute a potential pitfall for neuropathologists. Due to the absence of circulating blasts and a DNA-methylation signature, the diagnosis must currently be made by highlighting the translocation and expression of erythroid markers.

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.

Neurofibromatosis type 1 mosaicism in patients with constitutional mismatch repair deficiency.

Differential diagnosis between constitutional mismatch repair deficiency (CMMRD) and neurofibromatosis type 1 (NF1) is crucial as treatment and surveillance differ. We report the case of a girl with a clinical diagnosis of sporadic NF1 who developed a glioblastoma. Immunohistochemistry for MMR proteins identified PMS2 loss in tumour and normal cells and WES showed the tumour had an ultra-hypermutated phenotype, supporting the diagnosis of CMMRD. Germline analyses identified two variants (one pathogenic variant and one classified as variant(s) of unknown significance) in the PMS2 gene and subsequent functional assays on blood lymphocytes confirmed the diagnosis of CMMRD. The large plexiform neurofibroma of the thigh and the freckling were however more compatible with NF1. Indeed, a NF1 PV (variant allele frequencies of 20%, 3% and 9% and in blood, skin and saliva samples, respectively) was identified confirming a mosaicism for NF1. Retrospective analysis of a French cohort identified NF1 mosaicism in blood DNA in 2 out of 22 patients with CMMRD, underlining the existence of early postzygotic PV of NF1 gene in patients with CMMRD whose tumours have been frequently reported to exhibit somatic NF1 mutations. It highlights the potential role of this pathway in the pathogenesis of CMMRD-associated gliomas and argues in favour of testing MEK inhibitors in this context.

Imaging features to distinguish posterior fossa ependymoma subgroups.

OBJECTIVES: Posterior fossa ependymoma group A (EPN_PFA) and group B (EPN_PFB) can be distinguished by their DNA methylation and give rise to different prognoses. We compared the MRI characteristics of EPN_PFA and EPN_PFB at presentation. METHODS: Preoperative imaging of 68 patients with posterior fossa ependymoma from two centers was reviewed by three independent readers, blinded for histomolecular grouping. Location, tumor extension, tumor volume, hydrocephalus, calcifications, tissue component, enhancement or diffusion signal, and histopathological data (cellular density, calcifications, necrosis, mitoses, vascularization, and microvascular proliferation) were compared between the groups. Categorical data were compared between groups using Fisher's exact tests, and quantitative data using Mann-Whitney tests. We performed a Benjamini-Hochberg correction of the p values to account for multiple tests. RESULTS: Fifty-six patients were categorized as EPN_PFA and 12 as EPN_PFB, with median ages of 2 and 20 years, respectively (p = 0.0008). The median EPN_PFA tumoral volume was larger (57 vs 29 cm3, p = 0.003), with more pronounced hydrocephalus (p = 0.002). EPN_PFA showed an exclusive central position within the 4th ventricle in 61% of patients vs 92% for EPN_PFB (p = 0.01). Intratumor calcifications were found in 93% of EPN_PFA vs 40% of EPN_PFB (p = 0.001). Invasion of the posterior fossa foramina was mostly found for EPN_PFA, particularly the foramina of Luschka (p = 0.0008). EPN_PFA showed whole and homogeneous tumor enhancement in 5% vs 75% of EPN_PFB (p = 0.0008). All mainly cystic tumors were EPN_PFB (p = 0.002). The minimal and maximal relative ADC was slightly lower in EPN_PFA (p = 0.02 and p = 0.01, respectively). CONCLUSION: Morphological characteristics from imaging differ between posterior fossa ependymoma subtypes and may help to distinguish them preoperatively. CLINICAL RELEVANCE STATEMENT: This study provides a tool to differentiate between group A and group B ependymomas, which will ultimately allow the therapeutic strategy to be adapted in the early stages of patient management. KEY POINTS: • Posterior fossa ependymoma subtypes often have different imaging characteristics. • Posterior fossa ependymomas group A are commonly median or lateral tissular calcified masses, with incomplete enhancement, affecting young children and responsible for pronounced hydrocephalus and invasion of the posterior fossa foramina. • Posterior fossa ependymomas group B are commonly median non-calcified masses of adolescents and adults, predominantly cystic, and minimally invasive, with total and homogeneous enhancement.

Dispensing Oral Temozolomide in Children: Precision and Stability of a Novel and Ready to Use Liquid Formulation in Comparison with Capsule Derived Mixtures.

Temozolomide (TMZ) is part of the therapeutic armamentarium used in managing pediatric cancers; however, available oral forms (capsules) are not adapted for use in children. Our aim was to assess the dose accuracy and stability of TMZ using capsule contents mixed with food compared with a novel, ready-to-use liquid formulation specifically developed for children (Ped-TMZ, brand name KIZFIZO). Dose accuracy and TMZ stability testing were performed with TMZ capsule contents (90 mg) mixed with food vehicles (apple juice, apple sauce, cream, milk, and mashed potatoes) and compared to an equivalent dose of Ped-TMZ. Acceptance criteria were predefined for TMZ (95.0-105.0%) and its degradation product amino-imidazole-carboxamide (AIC; <1%) content. The delivered dose was significantly higher using Ped-TMZ (96.6 ± 1.2%) and within the predefined criteria for TMZ content, whereas it was systematically under the lower specifications of 95% using capsule-derived preparations with apple juice (91.0 ± 1.5%) and apple sauce (91.6 ± 1.4%), respectively (p < 0.0001). In chemical stability tests, the four food vehicles (apple sauce, cream, milk, mashed potatoes) had a significant effect on TMZ stability (p = 0.0042), and the AIC significantly increased with time in three of the four vehicles (p < 0.0001). Only 1/72 of preparations from capsules met the predefined acceptance criteria, whereas Ped-TMZ showed no TMZ loss, and the AIC remained within specifications. In conclusion, mixing TMZ capsule content with food may result in significant underexposure, possibly even greater in routine practice, as complete food intake by the child is unlikely.

Laser interstitial thermal therapy is effective and safe for the treatment of brain tumors in NF1 patients after cerebral revascularization for moyamoya angiopathy: a report on two cases.

Background: The co-occurrence of moyamoya vasculopathy and extra-optic pathway tumors is rare in neurofibromatosis type 1 (NF1), with only four cases described in the literature. Brain surgery in these patients may be challenging because of the risk of brain infarction after skin and dural incision. Given its percutaneous and minimally invasive nature, laser interstitial thermal therapy (LITT) is an ideal option for the treatment of brain tumors in these patients. Here, we report on two patients with NF1 and moyamoya syndrome (MMS) treated for a brain glioma with LITT, after cerebral revascularization. Cases: The first patient, with familial NF1, underwent bilateral indirect revascularization with multiple burr holes (MBH) for symptomatic MMS. Two years later, she was diagnosed with a left temporal tumor, with evidence of radiologic progression over 10 months. The second patient, also with familial NF1, developed unilateral MMS when he was 6 years old and was treated with MBH. At the age of 15 years, MRI showed a right cingular lesion, growing on serial MRIs. Both patients underwent LITT with no perioperative complications; they are progression free at 10 and 12 months, respectively, and the tumors have decreased in volume. Discussion: While the association of extra-optic neoplasm and moyamoya angiopathy is seldom reported in NF1, tumor treatment is challenging in terms of both avoiding stroke and achieving oncological control. Here, we show in 2 cases, that LITT could be a safe and effective option in these rare conditions.

Measuring Safety and Outcomes for the Use of Compassionate and Off-Label Therapies for Children, Adolescents, and Young Adults With Cancer in the SACHA-France Study.

Importance: Innovative anticancer therapies for children, adolescents, and young adults are regularly prescribed outside their marketing authorization or through compassionate use programs. However, no clinical data of these prescriptions is systematically collected. Objectives: To measure the feasibility of the collection of clinical safety and efficacy data of compassionate and off-label innovative anticancer therapies, with adequate pharmacovigilance declaration to inform further use and development of these medicines. Design, Setting, and Participants: This cohort study included patients treated at French pediatric oncology centers from March 2020 to June 2022. Eligible patients were aged 25 years or younger with pediatric malignant neoplasms (solid tumors, brain tumors, or hematological malignant neoplasms) or related conditions who received compassionate use or off-label innovative anticancer therapies. Follow up was conducted through August 10, 2022. Exposures: All patients treated in a French Society of Pediatric Oncology (SFCE) center. Main Outcomes and Measures: Collection of adverse drug reactions and anticancer activity attributable to the treatment. Results: A total of 366 patients were included, with a median age of 11.1 years (range, 0.2-24.6 years); 203 of 351 patients (58%) in the final analysis were male. Fifty-five different drugs were prescribed, half of patients (179 of 351 [51%]) were prescribed these drugs within a compassionate use program, mainly as single agents (74%) and based on a molecular alteration (65%). Main therapies were MEK/BRAF inhibitors followed by multi-targeted tyrosine kinase inhibitors. In 34% of patients at least a grade 2 clinical and/or grade 3 laboratory adverse drug reaction was reported, leading to delayed therapy and permanent discontinuation of the innovative therapy in 13% and 5% of patients, respectively. Objective responses were reported in 57 of 230 patients (25%) with solid tumors, brain tumors, and lymphomas. Early identification of exceptional responses supported the development of specific clinical trials for this population. Conclusions and Relevance: This cohort study of the SACHA-France (Secured Access to Innovative Medicines for Children with Cancer) suggested the feasibility of prospective multicenter clinical safety and activity data collection for compassionate and off-label new anticancer medicines. This study allowed adequate pharmacovigilance reporting and early identification of exceptional responses allowing further pediatric drug development within clinical trials; based on this experience, this study will be enlarged to the international level.

Circulating Tumor DNA Is Prognostic in Intermediate-Risk Rhabdomyosarcoma: A Report From the Children's Oncology Group.

PURPOSE: Novel biomarkers are needed to differentiate outcomes in intermediate-risk rhabdomyosarcoma (IR RMS). We sought to evaluate strategies for identifying circulating tumor DNA (ctDNA) in IR RMS and to determine whether ctDNA detection before therapy is associated with outcome. PATIENTS AND METHODS: Pretreatment serum and tumor samples were available from 124 patients with newly diagnosed IR RMS from the Children's Oncology Group biorepository, including 75 patients with fusion-negative rhabdomyosarcoma (FN-RMS) and 49 with fusion-positive rhabdomyosarcoma (FP-RMS) disease. We used ultralow passage whole-genome sequencing to detect copy number alterations and a new custom sequencing assay, Rhabdo-Seq, to detect rearrangements and single-nucleotide variants. RESULTS: We found that ultralow passage whole-genome sequencing was a method applicable to ctDNA detection in all patients with FN-RMS and that ctDNA was detectable in 13 of 75 serum samples (17%). However, the use of Rhabdo-Seq in FN-RMS samples also identified single-nucleotide variants, such as MYOD1L122R, previously associated with prognosis. Identification of pathognomonic translocations between PAX3 or PAX7 and FOXO1 by Rhabdo-Seq was the best method for measuring ctDNA in FP-RMS and detected ctDNA in 27 of 49 cases (55%). Patients with FN-RMS with detectable ctDNA at diagnosis had significantly worse outcomes than patients without detectable ctDNA (event-free survival, 33.3% v 68.9%; P = .0028; overall survival, 33.3% v 83.2%; P < .0001) as did patients with FP-RMS (event-free survival, 37% v 70%; P = .045; overall survival, 39.2% v 75%; P = .023). In multivariable analysis, ctDNA was independently associated with worse prognosis in FN-RMS but not in the smaller FP-RMS cohort. CONCLUSION: Our study demonstrates that baseline ctDNA detection is feasible and is prognostic in IR RMS.

Assessment of Puberty and Hypothalamic-Pituitary-Gonadal Axis Function After Childhood Brain Tumor Treatment.

CONTEXT: Endocrine complications are common in pediatric brain tumor patients. OBJECTIVE: To describe hypothalamic-pituitary-gonadal axis (HPGA) function in patients treated in childhood for a primary brain tumor more than 5 years earlier, in order to identify risk factors for HPGA impairment. METHODS: We retrospectively included 204 patients diagnosed with a primary brain tumor before 18 years of age and monitored at the pediatric endocrinology unit of the Necker Enfants-Malades University Hospital (Paris, France) between January 2010 and December 2015. Patients with pituitary adenoma or untreated glioma were excluded. RESULTS: Among patients with suprasellar glioma not treated by radiotherapy, the prevalence of advanced puberty was 65% overall and 70% when the diagnosis occurred before 5 years of age. Medulloblastoma chemotherapy caused gonadal toxicity in 70% of all patients and in 87.5% of those younger than 5 years at diagnosis. In the group with craniopharyngioma, 70% of patients had hypogonadotropic hypogonadism, which was consistently accompanied by growth hormone deficiency. CONCLUSION: Tumor type, location, and treatment were the risk main factors for HPGA impairment. Awareness that onset can be delayed is essential to guide information of parents and patients, patient monitoring, and timely hormone replacement therapy.

GH and Childhood-onset Craniopharyngioma: When to Initiate GH Replacement Therapy?

CONTEXT: Craniopharyngioma is a benign brain tumor with frequent local recurrence or progression after treatment. GH replacement therapy (GHRT) is prescribed in children with GH deficiency resulting from childhood-onset craniopharyngioma. OBJECTIVE: To evaluate whether a shorter delay of GHRT initiation after childhood-onset craniopharyngioma completion therapy increased the risk of a new event (progression or recurrence). METHODS: Retrospective, observational, monocenter study. We compared a cohort of 71 childhood-onset patients with craniopharyngiomas treated with recombinant human GH (rhGH). Twenty-seven patients were treated with rhGH at least 12 months after craniopharyngioma treatment (>12-month group) and 44 patients before 12 months (<12-month group), among which 29 patients were treated between 6 and 12 months (6-12 month group). The main outcome was the risk of tumor new event (progression of residual tumor or tumor recurrence after complete resection) after primary treatment in the >12-month group and in the <12 month or in the 6- to 12-month group patients. RESULTS: In the >12-month group, the 2- and 5-year event-free survivals were respectively 81.5% (95% CI, 61.1-91.9) and 69.4% (95% CI, 47.9-83.4) compared with 72.2% (95% CI, 56.3-83.1) and 69.8% (95% CI, 53.8-81.2) in the <12-month group. The 2- and 5-year event-free survivals were the same in the 6- to 12-month group (72.4%; 95% CI, 52.4-85.1). By log-rank test, the event-free survival was not different between groups (P = .98 and P = .91).The median time for event was not statistically different.In univariate and multivariate analysis, the risk of craniopharyngioma new event was not associated with the GHRT time delay after craniopharyngioma treatment. CONCLUSIONS: No association was found between GHRT time delay after childhood-onset craniopharyngioma treatment and an increased risk of recurrence or tumor progression, suggesting GH replacement therapy can be initiated 6 months after last treatment for craniopharyngiomas.

Development of a Hospital Compounded, Taste-Masked, Temozolomide Oral Suspension and 5-Year Real-Life Experience in Treating Paediatric Patients.

The development of oral pediatric forms by pharmaceutical companies is still insufficient. In fact, many drugs used in paediatric oncology, such as temozolomide, are not labeled and adapted for paediatric use. Temozolomide (TMZ) is an alkylating agent used as the standard of care for many adult and pediatric brain tumours, such as neuroblastoma, glioblastoma and medulloblastoma. The present study was carried out to propose a suitable and palatable formulation of the oral liquid preparation of TMZ. The suspension is composed of TMZ suspended in SyrSpend SF pH 4, as well as TMZ crystallization stabilizing agents and sweetening agents. To reach this formulation, several taste-masking agents were evaluated. Here, we describe the method of preparation of the formation as well as the monocentric population treated with the formulation over a 5-year period. A 20 mg/mL TMZ suspension was developed. TMZ suspension is stable for 6 weeks, stored between 2 and 8 degrees, protected from light, and compatible with nasogastric tubes. Thirty-eight patients participated in the palatability study and choose cola flavour, and 104 patients were treated in Gustave Roussy with the developed suspension; no unexpected event was reported. To conclude, we propose here a new TMZ liquid formulation which is stable for at least 6 weeks and well-tolerated with extensive feedback.

The European MAPPYACTS Trial: Precision Medicine Program in Pediatric and Adolescent Patients with Recurrent Malignancies.

ABSTRACT: MAPPYACTS (NCT02613962) is an international prospective precision medicine trial aiming to define tumor molecular profiles in pediatric patients with recurrent/refractory malignancies in order to suggest the most adapted salvage treatment. From February 2016 to July 2020, 787 patients were included in France, Italy, Ireland, and Spain. At least one genetic alteration leading to a targeted treatment suggestion was identified in 436 patients (69%) with successful sequencing; 10% of these alterations were considered "ready for routine use." Of 356 patients with follow-up beyond 12 months, 107 (30%) received one or more matched targeted therapies-56% of them within early clinical trials-mainly in the AcSé-ESMART platform trial (NCT02813135). Overall, matched treatment resulted in a 17% objective response rate, and of those patients with ready for routine use alterations, it was 38%. In patients with extracerebral tumors, 76% of actionable alterations detected in tumor tissue were also identified in circulating cell-free DNA (cfDNA). SIGNIFICANCE: MAPPYACTS underlines the feasibility of molecular profiling at cancer recurrence in children on a multicenter, international level and demonstrates benefit for patients with selected key drivers. The use of cfDNA deserves validation in prospective studies. Our study highlights the need for innovative therapeutic proof-of-concept trials that address the underlying cancer complexity. This article is highlighted in the In This Issue feature, p. 1171.

Rapid and highly sensitive approach for multiplexed somatic fusion detection.

Somatic gene translocations are key to making an accurate diagnosis in many cancers including many pediatric sarcomas. Currently available molecular diagnostic approaches to identifying somatic pathognomonic translocations have limitations such as minimal multiplexing, high cost, complex computational requirements, or slow turnaround times. We sought to develop a new fusion-detection assay optimized to mitigate these challenges. To accomplish this goal, we developed a highly sensitive multiplexed digital PCR-based approach that can identify the gene partners of multiple somatic fusion transcripts. This assay was validated for specificity with cell lines and synthetized DNA fragments. Assay sensitivity was optimized using a tiered amplification approach for fusion detection from low input and/or degraded RNA. The assay was then tested for the potential application of fusion detection from FFPE tissue and liquid biopsy samples. We found that this multiplexed PCR approach was able to accurately identify the presence of seven different targeted fusion transcripts with a turnaround time of 1 to 2 days. The addition of a tiered amplification step allowed the detection of targeted fusions from as little as 1 pg of RNA input. We also identified fusions from as little as two unstained slides of FFPE tumor biopsy tissue, from circulating tumor cells collected from tumor-bearing mice, and from liquid biopsy samples from patients with known fusion-positive cancers. We also demonstrated that the assay could be easily adapted for additional fusion targets. In summary, this novel assay detects multiple somatic fusion partners in biologic samples with low tumor content and low-quality RNA in less than two days. The assay is inexpensive and could be applied to surgical and liquid biopsies, particularly in places with inadequate resources for more expensive and expertise-dependent assays such as next-generation sequencing.

High Prevalence of Early Endocrine Disorders After Childhood Brain Tumors in a Large Cohort.

CONTEXT: Endocrine complications are common in pediatric brain tumor patients. OBJECTIVE: We aimed to describe the endocrine follow-up of patients with primary brain tumors. METHODS: This is a noninterventional observational study based on data collection from medical records of 221 patients followed at a Pediatric Endocrinology Department. RESULTS: Median age at diagnosis was 6.7 years (range, 0-15.9), median follow-up 6.7 years (0.3-26.6), 48.9% female. Main tumor types were medulloblastoma (37.6%), craniopharyngioma (29.0%), and glioma (20.4%). By anatomic location, 48% were suprasellar (SS) and 52% non-suprasellar (NSS). Growth hormone deficiency (GHD) prevalence was similar in both groups (SS: 83.0%, NSS: 76.5%; P = 0.338), appearing at median 1.8 years (-0.8 to 12.4) after diagnosis; postradiotherapy GHD appeared median 1.6 years after radiotherapy (0.2-10.7). Hypothyroidism was more prevalent in SS (76.4%), than NSS (33.9%) (P < 0.001), as well as ACTH deficiency (SS: 69.8%, NSS: 6.1%; P < 0.001). Early puberty was similar in SS (16%) and NSS (12.2%). Hypogonadotropic hypogonadism was predominant in SS (63.1%) vs NSS (1.3%), P < 0.001, and postchemotherapy gonadal toxicity in NSS (29.6%) vs SS (2.8%), P < 0.001. Adult height was lower for NSS compared to target height (-1.0 SD, P < 0.0001) and to SS patients (P < 0.0001). Thyroid nodules were found in 13/45 patients (28.8%), including 4 cancers (4.8-11.5 years after radiotherapy). Last follow-up visit BMI was higher in both groups (P = 0.0001), and obesity incidence was higher for SS (46.2%) than NSS (17.4%). CONCLUSION: We found a high incidence of early-onset endocrine disorders. An endocrine consultation and nutritional evaluation should be mandatory for all patients with a brain tumor, especially when the tumor is suprasellar or after hypothalamus/pituitary irradiation.