Outcome of children treated with preradiation chemotherapy for a high-grade glioma: results of a French Society of Pediatric Oncology (SFOP) Pilot Study

High-Grade Gliomas in Children-A Multi-Institutional Polish Study

Simple Summary

High-grade gliomas constitute less than 5% of pediatric brain tumors. Due to the rarity of such a diagnosis, the lack of consensus about the best therapeutic approach, and the difficulty in conducting prospective trials; a retrospective multi-institutional analysis, such as the one presented in this article, is needed. We carried out the survival analysis of children diagnosed and treated with high-grade gliomas in seven major polish institutions. The assessment of the outcome of 82 consecutive patients with grade III and grade IV tumors was performed and showed a 5-year overall survival of only 30%. The extent of resection, immediate temozolomide-based chemotherapy, and radical radiotherapy were found as factors positively influencing survival.

Abstract

Due to the rarity of high-grade gliomas (HGG) in children, data on this topic are scarce. The study aimed to investigate the long-term results of treatment of children with HGG and to identify factors related to better survival. We performed a retrospective analysis of patients treated for HGG who had the main tumor located outside the brainstem. The evaluation of factors that correlated with better survival was performed with the Cox proportional-hazard model. Survival was estimated with the Kaplan–Meier method. The study group consisted of 82 consecutive patients. All of them underwent surgery as primary treatment. Chemotherapy was applied in 93% of children with one third treated with temozolomide. After or during the systemic treatment, 79% of them received radiotherapy with a median dose of 54 Gy. Median follow-up was 122 months, and during that time, 59 patients died. One-, 2-, 5-, and 10-year overall survival was 78%, 48%, 30% and 17%, respectively. Patients with radical (R0) resection and temozolomide-based chemotherapy had better overall survival. Progression-free survival was better in patients after R0 resection and radical radiotherapy. The best outcome in HGG patients was observed in patients after R0 resection with immediate postoperative temozolomide-based chemotherapy and radical radiotherapy.

Evofosfamide Is Effective against Pediatric Aggressive Glioma Cell Lines in Hypoxic Conditions and Potentiates the Effect of Cytotoxic Chemotherapy and Ionizing Radiations

Simple Summary

Despite many therapeutic approaches attempted over the last years, the prognosis of children with high-grade glioma or diffuse intrinsic pontine glioma remains dismal. Hypoxia-activated prodrugs (HAPs) were developed to target hypoxic areas within solid tumors as gliomas. Evofosfamide (Evo) is a 2nd generation HAP exhibiting significant preclinical and clinical activities against adult glioblastoma. We thus investigated the potential of Evo in six pediatric glioma cell lines. Interestingly, we showed that the growth of all cell lines was inhibited by Evo, mainly under hypoxia as expected. We also evidenced a significant synergism between Evo and three drugs widely used in pediatric oncology. Finally, Evo appeared able to potentiate the effect of ionizing radiations. Since these tumors are highly hypoxic and Evo appears effective in hypoxic glioma cells as a single drug and in combination with radio- and chemotherapy, hypoxia-activated prodrugs could represent a promising therapeutic option for children with brain tumors.

Abstract

Hypoxia is a hallmark of many solid tumors and is associated with resistance to anticancer treatments. Hypoxia-activated prodrugs (HAPs) were developed to target the hypoxic regions of these tumors. Among 2nd generation HAPs, Evofosfamide (Evo, also known as TH-302) exhibits preclinical and clinical activities against adult glioblastoma. In this study, we evaluated its potential in the field of pediatric neuro-oncology. We assessed the efficacy of Evo in vitro as a single drug, or in combination with SN38, doxorubicin, and etoposide, against three pediatric high-grade glioma (pHGG) and three diffuse intrinsic pontine glioma (DIPG) cell lines under hypoxic conditions. We also investigated radio-sensitizing effects using clonogenic assays. Evo inhibited the growth of all cell lines, mainly under hypoxia. We also highlighted a significant synergism between Evo and doxorubicin, SN38, or etoposide. Finally, Evo radio-sensitized the pHGG cell line tested, both with fractionated and single-dose irradiation schedules. Altogether, we report here the first preclinical proof of evidence about Evofosfamide efficiency against hypoxic pHGG and DIPG cells. Since such tumors are highly hypoxic, and Evo potentiates the effect of ionizing radiation and chemotherapy, it appears as a promising therapeutic strategy for children with brain tumors.

Response assessment in paediatric high-grade glioma: recommendations from the Response Assessment in Pediatric Neuro-Oncology (RAPNO) working group

Response criteria for paediatric high-grade glioma vary historically and across different cooperative groups. The Response Assessment in Neuro-Oncology working group developed response criteria for adult high-grade glioma, but these were not created to meet the unique challenges in children with the disease. The Response Assessment in Pediatric Neuro-Oncology (RAPNO) working group, consisting of an international panel of paediatric and adult neuro-oncologists, clinicians, radiologists, radiation oncologists, and neurosurgeons, was established to address issues and unique challenges in assessing response in children with CNS tumours. We established a subcommittee to develop response assessment criteria for paediatric high-grade glioma. Current practice and literature were reviewed to identify major challenges in assessing the response of paediatric high-grade gliomas to various treatments. For areas in which scientific investigation was scarce, consensus was reached through an iterative process. RAPNO response assessment recommendations include the use of MRI of the brain and the spine, assessment of clinical status, and the use of corticosteroids or antiangiogenics. Imaging standards for brain and spine are defined. Compared with the recommendations for the management of adult high-grade glioma, for paediatrics there is inclusion of diffusion-weighted imaging and a higher reliance on T2-weighted fluid-attenuated inversion recovery. Consensus recommendations and response definitions have been established and, similar to other RAPNO recommendations, prospective validation in clinical trials is warranted.

Novel drugs in pediatric gliomas

Astrocytomas (gliomas) are the most common primary brain tumors among adults and second most frequent neoplasm among children. New ideas and novel approaches are being explored world over with aim to devise better management strategeies for this deadly pathological state. We searched the electronic database PubMed for pre-clinical as well as clinical controlled trials reporting importance of various therapeutic drugs against gliomas. It was observed clearly that this approach of using therapeutic drugs is clearly evolving and has been observed to be promising future therapeutic avenue against gliomas. The searched literature on whole revealed that although gliomas are treated aggressively with surgery, chemotherapy and radiation, treatment resistance, drug toxicity and poor response rates among pediatric glioma patients, continue to drive the need to discover new and more effective chemotherapeutic agents. The present review is focused on the latest updates in therapeutic drugs against gliomas in pediatric patients. The important chemo-therapeutics discussed in this review included alkylating agents like temoxolomide, derivatives of platinum, nitrosoureas, topoisomerases, angiogenesis inhibitors and cytomegalovirus as therapeutic agents.

The influence of central review on outcome in malignant gliomas of the spinal cord: the CCG-945 experience

OBJECT The impact of central pathology review on outcome has been described in pediatric patients with high-grade glioma (HGG). The objective of this report was to analyze the impact of the central pathology review on outcome in the subgroup of patients with institutional diagnosis of HGG of the spinal cord enrolled in the Children's Cancer Group 945 cooperative study. METHODS Five neuropathologists centrally reviewed the pathology of the 18 patients with HGG of the spinal cord who were enrolled in the study. These reviews were independent, and reviewers were blinded to clinical history and outcomes. A consensus diagnosis was established for each patient, based on the outcome of the review. RESULTS Of 18 patients, only 10 were confirmed to have HGG on central review. At a median follow-up of 12 years, event-free and overall survival for all 18 patients was 43.2% ± 13.3% and 50% ± 13.4%, respectively. After central review, 10-year event-free and overall survival for confirmed HGGs and discordant diagnoses was 30% ± 12.5% versus 58.3% ± 18.8% (p = 0.108) and 30% ± 12.5% versus 75% ± 14.2% (p = 0.0757), respectively. CONCLUSIONS The level of discordant diagnoses in children and adolescents with institutional diagnosis of HGG of the spinal cord was 44% in this experience. However, there was no significant difference in outcome between patients with confirmed and discordant diagnosis. This group of tumor deserves a specific attention in future trials.

Evaluating extent of resection in pediatric glioblastoma: a multiple propensity score-adjusted population-based analysis

PURPOSE

The benefit of radical resections for glioblastoma patients remains a source of contention in the literature. Few studies have been conducted in pediatric patients, and it is becoming increasingly evident that data regarding adult glioblastoma (GB) patients cannot be generalized to pediatric patients affected by this neoplasm. A comparative effectiveness study is performed for different extent of resection (EOR) groups in the largest cohort of pediatric GB (pGB) patients.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) cancer registry was used to identify pGB patients from 1988 through 2009. Multivariate- and multiple propensity score (mPS)-adjusted analyses were used to determine the effect of gross total resection (GTR), partial resection (PR), and biopsy (Bx) on overall survival. Survival prospects were summarized using direct adjusted survival curves.

RESULTS

A total of 342 pGB patients were identified, and 35.4 % of patients received a GTR, 28.8 % PR, 17.3 % Bx, and 17.0 % did not undergo surgery. In our cohort, a median overall survival of 12 months was observed with 1-, 2-, and 5-year survival rates of 51.7, 28.3, and 15.7 %, respectively. EOR was a predictor of survival in both the multivariate- (P < 0.001) and mPS-adjusted model (P < 0.001). Compared to the GTR group, a higher mortality rate was observed in patients who underwent a PR (HR 1.50; 95 % CI, 1.02-2.21) or Bx (HR 1.87; 95 % CI, 1.18-2.98). There were no significant differences in (adjusted) mortality risk between the PR and Bx groups.

CONCLUSION

Our study suggests that GTR is independently associated with improved survival for pediatric patients with glioblastoma.

Incidence and survival of children with central nervous system primitive tumors in the French National Registry of Childhood Solid Tumors

BACKGROUND

Central nervous system (CNS) tumors are the second most common childhood malignancy. The French National Registry of Childhood Solid Tumors (NRCST) makes it possible to describe this variety of distinct tumor types and to provide incidence and survival data in France on a nationwide basis.

METHODS

All children aged 0-14 years, who were registered with a primary CNS tumor in the NRCST of France between 2000 and 2008, were identified. Tumors were classified according to the International Classification of Childhood Cancer, third edition.

RESULTS

Approximately 57% of pediatric CNS tumors were gliomas, with astrocytomas of the pilocytic type predominating. Distributions of subtypes by age showed that primitive neuroectodermal tumors and ependymomas mainly occurred in children aged <5 years. The mean annual incidence rate of CNS tumors was 39 per million. No statistically significant change in time trends of incidence rate was observed during 2000-2008. For all tumors combined, overall survival was 84.8% (95% CI, 83.7%-85.9%) at 1 year and 72.9% (95% CI, 71.5%-74.3%) at 5 years. Survival time trends were studied in a multivariate analysis observing a reduction in the risk of death in periods of diagnosis 2003-2005 (HR = 0.8; 95% CI, 0.7–0.9) and 2006-2008 (HR = 0.7; 95% CI, 0.6-0.9) compared with 2000-2002.

CONCLUSIONS

The stable incidence rates during the last 10 years could indicate that major changes in environmental risk factors are unlikely, but the ongoing need for population-based surveillance remains relevant. Results indicate a positive trend in the survival probability still persistent in the 2000s.

Phase I study of non-pegylated liposomal doxorubicin in children with recurrent/refractory high-grade glioma

PURPOSE

To determine the maximum recommended dose (RD) and pharmacokinetics of Myocet®, a non-pegylated liposomal doxorubicin, in children.

METHODS

Eligible patients were children with refractory high-grade glioma who had received prior chemotherapy and radiotherapy but no anthracyclines. Cohorts of at least three patients each received escalating doses of Myocet® starting at 60 mg/m(2) at 3-week intervals, administered intravenously over 1 h, and then doses were escalated to 75 mg/m(2) corresponding to the adult RD. Periodic blood samples were collected, and plasma doxorubicin and doxorubicinol concentrations were quantified to characterise the pharmacokinetics of Myocet®.

RESULTS

Between October 2010 and January 2013, 13 children aged 6-17 years were treated. In total, 27 courses were administered, at the 60 mg/m(2) dose level in seven patients without dose-limiting toxicity (DLT), and at 75 mg/m(2) in six patients of whom two experienced DLT (grade 4 neutropenia). The most common grade 3-4 toxicities reported for all courses were neutropenia (35 and 38 %, respectively), thrombocytopenia (12 and 4 %, respectively); and grade 3 vomiting, nausea, mucositis, and fever (4 % each). Mean estimates of central volume of distribution at steady state, clearance, and elimination half-life of doxorubicin were 24.8 L, 15 L/h/m(2), and 34.8 h, respectively, with a large interpatient variability.

CONCLUSION

The RD of Myocet® administered every 3 weeks to paediatric patients was 60 mg/m(2). The efficacy of Myocet® in paediatric patients with high-grade glioma remains to be determined and should be studied in Phase II trials.

Management of high-grade gliomas in the pediatric patient: Past, present, and future

High-grade gliomas (HGGs) constitute ∼15% of all primary brain tumors in children and adolescents. Routine histopathological diagnosis is based on tissue obtained from biopsy or, preferably, from the resected tumor itself. The majority of pediatric HGGs are clinically and biologically distinct from histologically similar adult malignant gliomas; these differences may explain the disparate responses to therapy and clinical outcomes when comparing children and adults with HGG. The recently proposed integrated genomic classification identifies 6 distinct biological subgroups of glioblastoma (GBM) throughout the age spectrum. Driver mutations in genes affecting histone H3.3 (K27M and G34R/V) coupled with mutations involving specific proteins (TP53, ATRX, DAXX, SETD2, ACVR1, FGFR1, NTRK) induce defects in chromatin remodeling and may play a central role in the genesis of many pediatric HGGs. Current clinical practice in pediatric HGGs includes surgical resection followed by radiation therapy (in children aged > 3 years) with concurrent and adjuvant chemotherapy with temozolomide. However, these multimodality treatment strategies have had a minimal impact on improving survival. Ongoing clinical trials are investigating new molecular targets, chemoradiation sensitization strategies, and immunotherapy. Future clinical trials of pediatric HGG will incorporate the distinction between GBM molecular subgroups and stratify patients using group-specific biomarkers.

Comparison of survival between the UK and US after surgery for most common pediatric CNS tumors

BACKGROUND

We report a population-based study examining long-term outcomes for common pediatric CNS tumors comparing results from the UK with the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) data set and with the literature. No such international study has previously been reported.

METHODS

Data between 1996 and 2005 from the UK National Registry of Childhood Tumours (NRCT) and the SEER registry were analyzed. We calculated actuarial survival at each time point from histological diagnosis, with death from any cause as the endpoint. Kaplan-Meier estimation and log-rank testing (Cox proportional hazards regression analysis) were used to calculate survival differences among tumor subtypes, adjusting for age at diagnosis.

RESULTS

Population-based outcomes for each tumor type are presented. Overall age-adjusted survival, stratifying for histology (combining pilocytic astrocytoma, anaplastic astrocytoma, glioblastoma, primitive neuroectodermal tumor, medulloblastoma, and ependymoma), is significantly lower for NRCT than SEER (hazard ratio 0.71, P < .001) and at 1, 5, and 10 years. Both NRCT and SEER outcomes are worse than those reported from trials.

CONCLUSION

Analyzing data from comprehensive registries minimizes bias associated with trials and institutional studies. The reasons for the poorer outcomes in children treated in the UK are unclear. Likewise, the differences in outcomes between patients in trials and those not in trials need further investigation. We recommend that all children with CNS tumors be recruited into studies-even if these are observational studies. We also suggest that registries be suitably funded to publish independent outcome data (including morbidity) at both a national and an institutional level.

Central nervous system tumors

Central nervous system tumors are the most frequent malignant tumor in children and the main cause of death in this age group after traffic accidents. The current estimates are that one adult in 2500 is a survivor of a brain tumor that occurred during childhood. These tumors are particularly heterogeneous in terms of histology/biology, treatment, and outcome. They share, however, a high risk of neurological and cognitive morbidity due to the disease itself and the treatment modalities (radiotherapy, surgery, and chemotherapy). Diagnosis is frequently delayed because symptoms are usually nonspecific at the beginning of the evolution. Posterior fossa is the most frequent site and the tumors present most frequently with signs of intracranial hypertension. Supratentorial tumors are more frequent in infants and in adolescents; seizures are not uncommon, especially for benign tumors. When adjuvant treatment is needed, radiotherapy is usually the mainstay apart from some histologies where chemotherapy may be sufficient: low-grade gliomas, desmoplastic medulloblastomas, malignant glial tumors in infants. Multidisciplinary care is best performed in tertiary care centers and should include early rehabilitation programs soon after surgery.

Paediatric and adult malignant glioma: close relatives or distant cousins?

Gliomas in children differ from their adult counterparts by their distribution of histological grade, site of presentation and rate of malignant transformation. Although rare in the paediatric population, patients with high-grade gliomas have, for the most part, a comparably dismal clinical outcome to older patients with morphologically similar lesions. Molecular profiling data have begun to reveal the major genetic alterations underpinning these malignant tumours in children. Indeed, the accumulation of large datasets on adult high-grade glioma has revealed key biological differences between the adult and paediatric disease. Furthermore, subclassifications within the childhood age group can be made depending on age at diagnosis and tumour site. However, challenges remain on how to reconcile clinical data from adult patients to tailor novel treatment strategies specifically for paediatric patients.

A phase I and biology study of gefitinib and radiation in children with newly diagnosed brain stem gliomas or supratentorial malignant gliomas

PURPOSE

To estimate the maximum-tolerated dose (MTD); study the pharmacology of escalating doses of gefitinib combined with radiation therapy in patients ⩽21 years with newly diagnosed intrinsic brainstem gliomas (BSG) and incompletely resected supratentorial malignant gliomas (STMG); and to investigate epidermal growth factor receptor (EGFR) amplification and expression in STMG.

PATIENTS AND METHODS

Three strata were identified: stratum 1A--BSG; stratum IB--incompletely resected STMG not receiving enzyme-inducing anticonvulsant drugs (EIACD); and stratum II--incompletely resected STMG receiving EIACD. Dose escalation using a modified 3+3 cohort design was performed in strata IA and II. The initial gefitinib dosage was 100mg/m(2)/d commencing with radiation therapy and the dose-finding period extended until 2 weeks post-radiation. Pharmacokinetics (PK) and biology studies were performed in consenting patients.

RESULTS

Of the 23 eligible patients, 20 were evaluable for dose-finding. MTDs for strata IA and II were not established as accrual was halted due to four patients experiencing symptomatic intratumoral haemorrhage (ITH); two during and two post dose-finding. ITH was observed in 0 of 11 patients treated at 100mg/m(2)/d, 1 of 10 at 250 mg/m(2)/d and 3 of 12 at 375 mg/m(2)/d. Subsequently a second patient at 250 mg/m(2)/d experienced ITH. PK analysis showed that the median gefitinib systemic exposure increased with dosage (p = 0.04). EGFR was over-expressed in 5 of 11 STMG and amplified in 4 (36%) samples.

CONCLUSION

This trial provides clear evidence of EGFR amplification in a significant proportion of paediatric STMG and 250 mg/m(2)/d was selected for the phase II trial.

High dose methotrexate for pediatric high grade glioma: results of the HIT-GBM-D pilot study

We conducted a phase II study to test methotrexate (5 g/m(2)), as a single agent prior to radiochemotherapy for pediatric high-grade glioma and diffuse intrinsic pontine glioma. Thirty patients (19 male, median age 10.8) were enrolled. Tumors were located as follows: cortex 10, pons 7, other 13. Tumor resection was classified as gross total in 6, subtotal in 6, partial in 4, biopsy in 11 and not performed in 3. WHO grading of the histology was: IV: 11, III: 12 and II: 3. Patients received methotrexate 5 g/m(2) in 24-hour infusions on days 1 and 15. Subsequently 54 Gy radiation was administered with simultaneous chemotherapy including cisplatin, etoposide, vincristine and ifosfamide as previously described. Eight 6-weeks cycles of maintenance chemotherapy consisted of vincristine 1.5 mg/m(2) on days 1, 8 and 15; lomustine 100 mg/m(2) on day 2 and prednisone 40 mg/kg on days 1-17. Event-free survival rates in the whole group of 30 patients were: 43, 20, and 13% after 1, 2 and 5 years, respectively. The response evaluation after methotrexate was available in 19 of the 24 patients who started treatment with measurable disease: CR: 0, PR: 1, SD 18, PD: 0. After radiochemotherapy the response of 24 patients with measurable disease was CR: 1, PR 10, SD 12, PD 1. Both response and event-free survival were superior to the control group of 330 patients treated in various protocols of the same cooperative group. In subgroup analyses the use of dexamethasone during early treatment was linked to poor event free survival. Giving two cycles of high-dose methotrexate prior to radiochemotherapy was feasible, and the approach was taken forward to a randomized phase III trial.

Intensive chemotherapy improves survival in pediatric high-grade glioma after gross total resection: results of the HIT-GBM-C protocol

BACKGROUND

The authors hypothesized that intensified chemotherapy in protocol HIT-GBM-C would increase survival of pediatric patients with high-grade glioma (HGG) and diffuse intrinsic pontine glioma (DIPG).

METHODS

Pediatric patients with newly diagnosed HGG and DIPG were treated with standard fractionated radiation and simultaneous chemotherapy (cisplatin 20 mg/m2 x 5 days, etoposide 100 mg/m2 x 3 days, and vincristine, and 1 cycle of cisplatin + etoposide + ifosfamide 1.5 g/m x 5 days [PEI] during the last week of radiation). Subsequent maintenance chemotherapy included further cycles of PEI in Weeks 10, 14, 18, 22, 26, and 30, followed by oral valproic acid.

RESULTS

Ninety-seven (pons, 37; nonpons, 60) patients (median age, 10 years; grade IV histology, 35) were treated. Resection was complete in 21 patients, partial in 29, biopsy only in 26, and not performed in 21. Overall survival rates were 91% (standard error of the mean [SE] +/- 3%), 56%, and 19% at 6, 12, and 60 months after diagnosis, respectively. When compared with previous protocols, there was no significant benefit for patients with residual tumor, but the 5-year overall survival rate for patients with complete resection treated on HIT-GBM-C was 63% +/- 12% SE, compared with 17% +/- 10% SE for the historical control group (P = .003, log-rank test).

CONCLUSIONS

HIT-GBM-C chemotherapy after complete tumor resection was superior to previous protocols.

[Diffuse intrinsic brain stem glioma in children: current treatment and future directions]

Despite the numerous clinical trials undertaken, the prognosis of children with diffuse brain stem glioma remains very poor. This review examines the different strategies for the treatment of malignant brain stem glioma such as radiation therapy, concurrent radiochemotherapy, and classical cytotoxic drugs, with a particular focus on the novel targeted and antiangiogenic drugs recently introduced in pediatric oncology. The strategy using integrin inhibitors is discussed.

Pediatric brain tumors: current treatment strategies and future therapeutic approaches

Pediatric CNS tumors are the most common solid tumors of childhood and the second most common cancer after hematological malignancies accounting for approximate 20 to 25% of all primary pediatric tumors. With over 3,000 new cases per year in the United States, childhood CNS tumors are the leading cause of death related to cancer in this population. The prognosis for these patients has improved over the last few decades, but current therapies continue to carry a high risk of significant side effects, especially for the very young. Currently a combination of surgery, radiation, and chemotherapy is often used in children greater than 3 years of age. This article will outline current and future therapeutic strategies for the most common pediatric CNS tumors, including primitive neuroectodermal tumors such as medulloblastoma, as well as astrocytomas and ependymomas.

Herpes simplex virus oncolytic therapy for pediatric malignancies

Despite improving survival rates for children with cancer, a subset of patients exist with disease resistant to traditional therapies such as surgery, chemotherapy, and radiation. These patients require newer, targeted treatments used alone or in combination with more traditional approaches. Oncolytic herpes simplex virus (HSV) is one of these newer therapies that offer promise for several difficult to treat pediatric malignancies. The potential benefit of HSV therapy in pediatric solid tumors including brain tumors, neuroblastomas, and sarcomas is reviewed along with the many challenges that need to be addressed prior to moving oncolytic HSV therapy from the laboratory to the beside in the pediatric population.