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.

Implementation of DNA Methylation Array Profiling in Pediatric Central Nervous System Tumors: The AIM BRAIN Project: An Australian and New Zealand Children's Haematology/Oncology Group Study.

DNA methylation array profiling for classifying pediatric central nervous system (CNS) tumors is a valuable adjunct to histopathology. However, unbiased prospective and interlaboratory validation studies have been lacking. The AIM BRAIN diagnostic trial involving 11 pediatric cancer centers in Australia and New Zealand was designed to test the feasibility of routine clinical testing and ran in parallel with the Molecular Neuropathology 2.0 (MNP2.0) study at Deutsches Krebsforschungszentrum (German Cancer Research Center). CNS tumors from 269 pediatric patients were prospectively tested on Illumina EPIC arrays, including 104 cases co-enrolled on MNP2.0. Using MNP classifier versions 11b4 and 12.5, we report classifications with a probability score ≥0.90 in 176 of 265 (66.4%) and 213 of 269 (79.2%) cases, respectively. Significant diagnostic information was obtained in 130 of 176 (74%) for 11b4, and 12 of 174 (7%) classifications were discordant with histopathology. Cases prospectively co-enrolled on MNP2.0 gave concordant classifications (99%) and score thresholds (93%), demonstrating excellent test reproducibility and sensitivity. Overall, DNA methylation profiling is a robust single workflow technique with an acceptable diagnostic yield that is considerably enhanced by the extensive subgroup and copy number profile information generated by the platform. The platform has excellent test reproducibility and sensitivity and contributes significantly to CNS tumor diagnosis.

BRAF-mediated brain tumors in adults and children: A review and the Australian and New Zealand experience.

The mitogen-activated protein kinase (MAPK) pathway signaling pathway is one of the most commonly mutated pathways in human cancers. In particular, BRAF alterations result in constitutive activation of the rapidly accelerating fibrosarcoma-extracellular signal-regulated kinase-MAPK significant pathway, leading to cellular proliferation, survival, and dedifferentiation. The role of BRAF mutations in oncogenesis and tumorigenesis has spurred the development of targeted agents, which have been successful in treating many adult cancers. Despite advances in other cancer types, the morbidity and survival outcomes of patients with glioma have remained relatively stagnant. Recently, there has been recognition that MAPK dysregulation is almost universally present in paediatric and adult gliomas. These findings, accompanying broad molecular characterization of gliomas, has aided prognostication and offered opportunities for clinical trials testing targeted agents. The use of targeted therapies in this disease represents a paradigm shift, although the biochemical complexities has resulted in unexpected challenges in the development of effective BRAF inhibitors. Despite these challenges, there are promising data to support the use of BRAF inhibitors alone and in combination with MEK inhibitors for patients with both low-grade and high-grade glioma across age groups. Safety and efficacy data demonstrate that many of the toxicities of these targeted agents are tolerable while offering objective responses. Newer clinical trials will examine the use of these therapies in the upfront setting. Appropriate duration of therapy and durability of response remains unclear in the glioma patient cohort. Longitudinal efficacy and toxicity data are needed. Furthermore, access to these medications remains challenging outside of clinical trials in Australia and New Zealand. Compassionate access is limited, and advocacy for mechanism of action-based drug approval is ongoing.

Case Report: Precision Medicine Target Revealed by In Vitro Modeling of Relapsed, Refractory Acute Lymphoblastic Leukemia From a Child With Neurofibromatosis.

Children with neurofibromatosis have a higher risk of developing juvenile myelomonocytic leukemia and acute myeloid leukemia, but rarely develop B-cell acute lymphoblastic leukemia (B-ALL). Through in-vitro modeling, a novel NF1 p.L2467 frameshift (fs) mutation identified in a relapsed/refractory Ph-like B-ALL patient with neurofibromatosis demonstrated cytokine independence and increased RAS signaling, indicative of leukemic transformation. Furthermore, these cells were sensitive to the MEK inhibitors trametinib and mirdametinib. Bi-allelic NF1 loss of function may be a contributing factor to relapse and with sensitivity to MEK inhibitors, suggests a novel precision medicine target in the setting of neurofibromatosis patients with B-ALL.

Paediatric Gastrointestinal, Hepatic and Pancreatic Inflammatory Myofibroblastic Tumours, A Single Centre Experience.

ABSTRACT: Inflammatory myofibroblastic tumours (IMTs) are rare soft tissue tumours. Reports of gastrointestinal tract, liver and pancreas tumours are limited. The objective of this study is to identify presenting features, contributing prognostic / etiological factors and any variability in outcomes in the context of different historical treatments. We retrospectively reviewed the records of seven children treated at our hospital between 2006 and 2019 and assessed the demographic, presentation, treatment, immunohistochemistry, and outcomes of their tumours. Age range at presentation was 4 months-15 years with a male predominance. Presentations were typically due to local mass effect or incidental discovery. Systemic symptoms were rare. Outcomes were good with six out of seven stable or in remission irrespective of treatment. Surgical resection where possible is the treatment of choice. Medical therapy had good outcomes with chemotherapy acting as first line treatment when required. The only negative prognostic factor identified was local spread at the time of presentation.

Parents' experiences of postmortem tumor donation for high-grade gliomas: benefits and suggested improvements.

BACKGROUND: Pediatric high-grade glioma is a devastating diagnosis. There has been no improvement in outcomes for several decades, with few children surviving 2 years postdiagnosis. Research progress has been hampered by a lack of tumor samples, which can be used to develop and test novel therapies. Postmortem tumor donations are therefore a valuable opportunity to collect tissue. In this study, we explored Australian parents' experiences of donating their child's tumor for research after their child had died. METHODS: We collected qualitative data from 11 bereaved parents who consented to donate samples of their child's high-grade glioma for research postmortem. We asked parents about their perceived benefits/burdens of the autopsy, recommendations for improving consent discussions, and decision regret. RESULTS: Parents hoped that their donation would help to find a cure for future children with high-grade glioma. They described feeling comforted knowing that their child's suffering may help others. Some parents also felt that the donation would help them better understand their child's tumor. Although some parents described discomfort about procedures leading up to the autopsy, parents reported minimal regret regarding their decision to donate their child's tumor. Parents provided recommendations to improve consent discussions, such as providing more information about the autopsy logistics and why the donation was needed. CONCLUSION: Parents consented to autopsy for altruistic reasons, although donation may also assist parents in their grieving. There is a strong need to improve access to tumor donations for any family who wishes to donate.

Malignant Melanoma in Children and Adolescents Treated in Pediatric Oncology Centers: An Australian and New Zealand Children's Oncology Group (ANZCHOG) Study.

OBJECTIVES: Unlike adults, malignant melanoma in children and adolescents is rare. In adult melanoma, significant progress in understanding tumor biology and new treatments, including targeted therapies and immunotherapy have markedly improved overall survival. In sharp contrast, there is a paucity of data on the biology and clinical behavior of pediatric melanoma. We report a national case series of all pediatric and adolescent malignant melanoma presenting to ANZCHOG Childhood Cancer Centers in Australia and New Zealand. METHODS: A retrospective, descriptive, multi-center study was undertaken to identify patients less than 18 years of age treated for cutaneous malignant melanoma over a twenty-year period (1994 to 2014). Data on clinical characteristics, histopathology, and extent of disease, treatment and follow-up are described. RESULTS: A total of 37 cases of malignant melanoma were identified from all of the Australasian tertiary Childhood Cancer Centers. The median age was 10 years (range 1 month - 17 years). Clinically, the most common type of lesion was pigmented, occurring in sixteen (57%) patients, whilst amelanotic was seen in 7 patients (25%). In 11 (27.9%) the Breslow thickness was greater than 4mm. A total of 11 (29.7%) patients relapsed and 90% of these died of disease. Five-year event free survival (EFS) and overall survival were 63.2 (95% CI: 40.6 - 79.1) and 67.7% (95% CI: 45.1 - 82.6) respectively. CONCLUSION: Our data confirms that melanoma is a rare presentation of cancer to tertiary Australasian Childhood Cancer Centers with only 37 cases identified over two decades. Notably, melanoma managed in Childhood Cancer Centers is frequently at an advanced stage, with a high percentage of patients relapsing and the majority of these patients who relapsed died of disease. This study confirms previous clinical and prognostic information to support the early multidisciplinary management in Childhood Cancer Centers, in conjunction with expert adult melanoma centers, of this rare and challenging patient group.

Stage at diagnosis for childhood solid cancers in Australia: A population-based study.

BACKGROUND: Stage of cancer at diagnosis is one of the strongest predictors of survival and is essential for population cancer surveillance, comparison of cancer outcomes and to guide national cancer control strategies. Our aim was to describe, for the first time, the distribution of cases by stage at diagnosis and differences in stage-specific survival on a population basis for a range of childhood solid cancers in Australia. METHODS: The study cohort was drawn from the population-based Australian Childhood Cancer Registry and comprised children (<15 years) diagnosed with one of 12 solid malignancies between 2006 and 2014. Stage at diagnosis was assigned according to the Toronto Paediatric Cancer Stage Guidelines. Observed (all cause) survival was calculated using the Kaplan-Meier method, with follow-up on mortality available to 31 December 2015. RESULTS: Almost three-quarters (1256 of 1760 cases, 71%) of children in the study had localised or regional disease at diagnosis, varying from 43% for neuroblastoma to 99% for retinoblastoma. Differences in 5-year observed survival by stage were greatest for osteosarcoma (localised 85% (95% CI = 72%-93%) versus metastatic 37% (15%-59%)), neuroblastoma (localised 98% (91%-99%) versus metastatic 60% (52%-67%)), rhabdomyosarcoma (localised 85% (71%-93%) versus metastatic 53% (34%-69%)), and medulloblastoma (localised 69% (61%-75%) versus metastases to spine 42% (27%-57%)). CONCLUSION: The stage-specific information presented here provides a basis for comparison with other international population cancer registries. Understanding variations in survival by stage at diagnosis will help with the targeted formation of initiatives to improve outcomes for children with cancer.

Correction to: International experience in the development of patient-derived xenograft models of diffuse intrinsic pontine glioma.

There are two errors and one omission in the original article. Author Gottardo's correct name is Nicholas G. Gottardo, author Hulleman's correct affiliation is no. 3 (VUMC, Amsterdam), and the Acknowledgements should include the following sentence: "We would like to thank Dr Angel Montero Carcaboso (Hospital Sant Joan de Deu, Barcelona, Spain) for generously supplying the HSJD-DIPG007 cells."

International experience in the development of patient-derived xenograft models of diffuse intrinsic pontine glioma.

PURPOSE: Diffuse intrinsic pontine glioma is the most aggressive form of high grade glioma in children with no effective therapies. There have been no improvements in survival in part due poor understanding of underlying biology, and lack of representative in vitro and in vivo models. Recently, it has been found feasible to use both biopsy and autopsy tumors to generate cultures and xenograft models. METHODS: To further model development, we evaluated the collective international experience from 8 collaborating centers to develop DIPG pre-clinical models from patient-derived autopsies and biopsies. Univariate and multivariate analysis was performed to determine key factors associated with the success of in vitro and in vivo PDX development. RESULTS: In vitro cultures were successfully established from 57% of samples (84.2% of biopsies and 38.2% of autopsies). Samples transferred in DMEM media were more likely to establish successful culture than those transported in Hibernate A. In vitro cultures were more successful from biopsies (84.2%) compared with autopsies (38.2%) and as monolayer on laminin-coated plates than as neurospheres. Primary cultures successfully established from autopsy samples were more likely to engraft in animal models than cultures established from biopsies (86.7% vs. 47.4%). Collectively, tumor engraftment was more successful when DIPG samples were directly implanted in mice (68%), rather than after culturing (40.7%). CONCLUSION: This multi-center study provides valuable information on the success rate of establishing patient-derived pre-clinical models of DIPG. The results can lead to further optimization of DIPG model development and ultimately assist in the investigation of new therapies for this aggressive pediatric brain tumor.

Treatment delay and the risk of relapse in pediatric acute lymphoblastic leukemia.

Delays or interruptions in chemotherapy due to toxicity such as neutropenia or severe infections are common in the treatment of pediatric acute lymphoblastic leukemia (ALL). Based on the reports of worse outcomes in children with poorer compliance with therapy, there has been concern that toxicity-induced therapy interruptions could also compromise treatment outcome. In a retrospective study of treatment delays in our hospital between 2003 and 2013, the case notes of 141 patients were reviewed. The cumulative lengths of delays during the whole length of chemotherapy, during the intensive phase of treatment, and during maintenance treatment were analyzed. Within these categories, delays were split between less and more than the median value. The risk of relapse did not differ between patients with a longer or shorter delay during the total length of treatment or during the intensive phase. In addition, there was a trend when comparing patients above vs below the mean in length of treatment delays during maintenance, and there was a statistically significant difference in relapses when comparing patients in the lowest and highest quartiles of maintenance delays, with fewer relapses among those patients in the highest quartile for treatment delays.

Cancer in Australian Aboriginal children: room for improvement.

AIM: The study aims to analyse clinical data and outcome in Aboriginal and non-Aboriginal children with cancer. METHODS: This is a retrospective case-note review of biological features, treatment outcome and survival in Aboriginal and non-Aboriginal children with a malignancy who were treated at the Women's and Children's Hospital, a tertiary referral hospital, from January 1997 through March 2011. Two separate analyses were performed: firstly, for each Aboriginal patient comparisons were made with two age, sex and diagnosis-matched control patients; then secondly, results for the Aboriginal group of patients were compared with the whole non-Aboriginal group of patients. RESULTS: In the first analysis, Aboriginal children had a significantly higher 'remoteness index' (6.14 vs. 0.95; P < 0.001) and were less likely to be enrolled on clinical trials. Survival analysis of the Aboriginal patients and their matched controls showed a trend towards inferior overall survival for the Indigenous children (P = 0.066). In the second analysis, Aboriginal children tended to have a higher proportion of leukaemias and lymphomas and had an overrepresentation of acute myeloid leukaemia (AML) (P = 0.009). The mean age among Aboriginal children with AML and lymphoma was lower (AML: 3.5 vs. 8 years, P = 0.065; lymphoma: 7.5 vs. 11.9 years, P = 0.01). A higher proportion of Aboriginal children died (P = 0.004). CONCLUSIONS: Aboriginal children present with a somewhat different pattern of cancer, are less likely to be enrolled on studies and seem to have increased mortality. There is a need for improvement in study enrolment, treatment delivery, care coordination and suitably supported residential facilities.

ANZCCSG BabyBrain99; intensified systemic chemotherapy, second look surgery and involved field radiation in young children with central nervous system malignancy.

BACKGROUND: ANZCCSG BabyBrain99 is a trial of intensive systemic chemotherapy with dual stem cell supported treatment, second look surgery and involved field radiation for children less than four years of age with malignant central nervous system tumours. PROCEDURE: Following primary resection, treatment included two courses of cisplatin and oral etoposide, a third course of mobilising chemotherapy (vincristine, etoposide, cyclophosphamide) with stem cell harvest, followed by intensive stem cell supported chemotherapy with high dose cyclophosphamide, etoposide and vincristine. Children were evaluated for second resection before proceeding to a second stem cell supported consolidation therapy consisting of melphalan and carboplatin. Patients then received involved field radiation therapy. RESULTS: Thirty three children with a range of diagnoses were enrolled. Nine percent of children had metastatic disease at diagnosis. Eighteen children completed treatment including irradiation. At the end of induction the event free survival was 70% (54-86). Forty eight percent of children had a complete response, 18% had stable disease and 3% had a partial response. Five year overall survival was 40% (22-56) and event free survival was 33% (17-50). Children in whom a complete resection were achieved had a significantly superior outcome compared to those children without a complete resection, 5 year EFS 60% (45-75), as compared to 22% (13-30), P-value <0.05. CONCLUSIONS: BabyBrain99 confirms that intensive stem cell supported chemotherapy can be safely administered to infants with CNS tumours however overall prognosis remains poor. Importantly, the study reinforces a complete surgical resection as an important favourable prognostic indicator. Pediatr Blood Cancer 2011;56:1055-1061. © 2011 Wiley-Liss, Inc.

Maternal consumption of coffee and tea during pregnancy and risk of childhood ALL: results from an Australian case-control study.

OBJECTIVES: To investigate whether maternal coffee and/or tea consumption during the last 6 months of pregnancy was associated with risk of childhood ALL. METHODS: Data on coffee and tea drinking during pregnancy from 337 case mothers and 697 control mothers were analyzed using unconditional multivariable logistic regression. A meta-analysis of our findings with those of previous studies was also conducted. RESULTS: There was little evidence of an overall association between maternal coffee consumption and risk of ALL: OR 0.89 (95% CI 0.61, 1.30), although there was some suggestion that higher levels of intake might increase the risk in children of non-smoking mothers: OR for 2+ cups/day = 1.44 (95% CI 0.85, 2.42); this was supported by our meta-analysis. Risk was also elevated among cases with chromosomal translocations. The overall OR for maternal tea consumption was 0.82 (95% CI 0.56, 1.18), although the OR for T-cell ALL was 0.21 (95% CI 0.08, 0.51). Among ALL cases with translocations, the ORs for tea consumption tended to be elevated: OR = 1.70 (95% CI 0.79-3.68) for 2+ cups/day. CONCLUSIONS: The observed increased risk associated with coffee and tea consumption may be confined to ALL with translocations. These associations should be explored further in large international consortia.

Amniotic fluid embolism complicated by paradoxical embolism and disseminated intravascular coagulation.

Amniotic fluid embolism is a rare syndrome with potentially lethal outcomes. Complications include cardiorespiratory failure, disseminated intra-vascular coagulation, seizures, neurological deficits, and death. A 34-year-old woman had amniotic fluid embolism complicated by paradoxical embolism and disseminated intravascular coagulation. Emergency cesarean section followed by cardiopulmonary bypass with removal of the clot from the atria and closure of the patent foramen ovale was performed, resulting in a good outcome for both the mother and the baby. Subsequent treatment with anticoagulants for 6 months was recommended. A literature review revealed that this clinical scenario is rare but can be successfully managed by cardiopulmonary bypass and thromboembolectomy. Data on guidelines for the use of anticoagulation in this situation are limited.