Low Grade Chiasmatic-Hypothalamic Glioma - Carboplatin and Vincristin Chemotherapy Effectively Defers Radiotherapy within a Comprehensive Treatment Strategy

Laser interstitial thermal therapy (LITT) for pediatric low-grade glioma-case presentations and lessons learned

BACKGROUND

The surgical treatment of brain tumors has developed over time, offering customized strategies for patients and their specific lesions. One of the most recent advances in pediatric neuro-oncological surgery is laser interstitial thermal therapy (LITT). However, its effectiveness and indications are still being evaluated. The aim of this work is to review the current literature on LITT for pediatric low-grade gliomas (pLGG) and evaluate our initial results in this context.

METHODS

We retrospectively reviewed our pediatric neurosurgery database for patients who received LITT treatment between November 2019 and December 2023. We collected data on the indications for LITT, technical issues during the procedure, and clinical and radiological follow-up.

RESULTS

Three patients underwent 5 LITT procedures for pLGG. The lesion was thalamo-peduncular in one patient, cingulate in one, and deep parietal in one patient. Two patients had a previous open resection done and were diagnosed with pLGG. One patient underwent a stereotaxic biopsy during the LITT procedure that was non-diagnostic. The same patient underwent a later open resection of the tumor in the cingulate gyrus. There were no surgical complications and all patients were discharged home on the first post-operative day. The follow-up period was between 20 and 40 months. Radiological follow-up showed a progressive reduction of the tumor in patients with LGG.

CONCLUSION

Laser interstitial thermal therapy is a minimally invasive treatment that shows promise in treating deep-seated pLGG in children. The treatment has demonstrated a reduction in tumor volume, and the positive results continue over time. LITT can be used as an alternative treatment for tumors located in areas that are difficult to access surgically or in cases where other standard treatment options have failed.

Novel immune checkpoint-related gene model to predict prognosis and treatment responsiveness in low-grade gliomas

Recently, studies have shown that immune checkpoint-related genes (ICGs) are instrumental in maintaining immune homeostasis and can be regarded as potential therapeutic targets. However, the prognostic applications of ICGs require further elucidation in low-grade glioma (LGG) cases. In the present study, a unique prognostic gene signature in LGG has been identified and validated as well based on ICGs as a means of facilitating clinical decision-making. The RNA-seq data as well as corresponding clinical data of LGG samples have been retrieved utilizing the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. ICG-defined non-negative matrix factorization (NMF) clustering was performed to categorize patients with LGG into two molecular subtypes with different prognoses, clinical traits, and immune microenvironments. In the TCGA database, a signature integrating 8 genes has been developed utilizing the LASSO Cox method and validated in the GEO database. The signature developed is superior to other well-recognized signatures in terms of predicting the survival probability of patients with LGG. This 8-gene signature was then subsequently applied to categorize patients into high- and low-risk groups, and differences between them in terms of gene alteration frequency were observed. There were remarkable variations in IDH1 (91% and 64%) across low-as well as high-risk groups. Additionally, various analyses like function enrichment, tumor immune microenvironment, and chemotherapy drug sensitivity revealed significant variations across high- and low-risk populations. Overall, this 8-gene signature may function as a useful tool for prognosis and immunotherapy outcome predictions among LGG patients.

Long-term outcomes of symptomatic optic pathway glioma: 32-year experience at a single Western Australian tertiary pediatric oncology center

Introduction

Optic pathway gliomas (OPGs) are associated with significant risk of visual and endocrine morbidity, but data on long-term outcomes in symptomatic patients is sparse. This study reviews the clinical course, disease progression, survival outcomes and long-term sequelae in pediatric patients with symptomatic OPGs in our institution over three decades.

Methods

Retrospective review of patients with symptomatic OPG treated in a single tertiary pediatric oncology center from 1984 to 2016.

Results

A total of 37 patients were diagnosed with symptomatic OPG. Decreased visual acuity was the commonest presenting symptom (75.7%). Surgical intervention was performed in 62.2%; 56.5% underwent biopsy, 26.1% surgical debulking and 17.4% had orbital decompression with cystic fenestration and cosmetic optic nerve excision at different treatment intervals. CSF diversion was performed in 47.8% patients. Histopathologic examination confirmed 86% to be pilocytic astrocytoma and 1 ganglioglioma. 46% received chemotherapy and 48% had radiotherapy, at different intervals. Median follow-up was 13.74 years. In NF1 patients, overall survival (OS) was 100% at 5 years and 55.6 ± 24.8% at 25 years while progression-free-survival (PFS) was 50 ± 15.8% at 5 and 20 years. In non-NF1 patients, OS was 96.2 ± 3.8% at 5 years and 87.4 ± 9% at 25-years. 5-year PFS was 53.8 ± 9.8% and 25-year PFS was 49.0 ± 10%. Cumulative PFS was 53 ± 8.3% at 5 years and 49.7 ± 8.4% at 20 years while cumulative OS was 97.2 ± 2.7% at 5 years and 77.5 ± 10.8% at 25 years. 59.5% patients developed post-operative endocrinopathy. Long-term vision was normal in 8.1%, improved in 13.5%, stabilized in 40.5% but worsened in 37.8% patients. Three patients treated with radiotherapy developed second brain tumors.

Conclusion

25-year OS in this cohort was 77.5% but survivorship carried significant long-term morbidities including radiation-induced second malignant brain tumors.

Integrated response analysis of pediatric low-grade gliomas during and after targeted therapy treatment

Background

Pediatric low-grade gliomas (pLGGs) are the most common central nervous system tumor in children, characterized by RAS/MAPK pathway driver alterations. Genomic advances have facilitated the use of molecular targeted therapies, however, their long-term impact on tumor behavior remains critically unanswered.

Methods

We performed an IRB-approved, retrospective chart and imaging review of pLGGs treated with off-label targeted therapy at Dana-Farber/Boston Children's from 2010 to 2020. Response analysis was performed for BRAFV600E and BRAF fusion/duplication-driven pLGG subsets.

Results

Fifty-five patients were identified (dabrafenib n = 15, everolimus n = 26, trametinib n = 11, and vemurafenib n = 3). Median duration of targeted therapy was 9.48 months (0.12-58.44). The 1-year, 3-year, and 5-year EFS from targeted therapy initiation were 62.1%, 38.2%, and 31.8%, respectively. Mean volumetric change for BRAFV600E mutated pLGG on BRAF inhibitors was -54.11%; median time to best volumetric response was 8.28 months with 9 of 12 (75%) objective RAPNO responses. Median time to largest volume post-treatment was 2.86 months (+13.49%); mean volume by the last follow-up was -14.02%. Mean volumetric change for BRAF fusion/duplication pLGG on trametinib was +7.34%; median time to best volumetric response was 6.71 months with 3 of 7 (43%) objective RAPNO responses. Median time to largest volume post-treatment was 2.38 months (+71.86%); mean volume by the last follow-up was +39.41%.

Conclusions

Our integrated analysis suggests variability in response by pLGG molecular subgroup and targeted therapy, as well as the transience of some tumor growth following targeted therapy cessation.

Long-term treatment outcomes of pediatric low-grade gliomas treated at a university-based hospital

PURPOSE

A multimodality approach is generally considered for pediatric low-grade gliomas (LGG); however, the optimal management remains uncertain. The objective of the study was to evaluate treatment outcomes of pediatric LGG, focusing on long-term survival and factors related to outcomes.

METHODS

A retrospective review of 77 pediatric LGG cases treated at Ramathibodi Hospital, Thailand between 2000 and 2018 was performed. The inclusion criteria were all pediatric LGG cases aged ≤ 15 years. Diffuse intrinsic pontine gliomas and spinal cord tumors were excluded.

RESULTS

The median follow-up time was 8.2 years (range, 0.6-19.7). The median age at diagnosis was 6.2 years (interquartile range, 3.6-11.4). Treatments modality included tumor surgery (93%), chemotherapy (40%), and radiation therapy (14%). The 10-year overall survival (OS) and 10-year progression-free survival were 94% and 59%, respectively, for the entire cohort. The 10-year OS was 100% in three subgroups of patients: pilocytic subtype, WHO grade 1 tumors, and recipient of gross total resection. After multivariable analysis, no tumor surgery had a significantly unfavorable influence on overall survival.

CONCLUSIONS

With a multimodality approach, pediatric LGGs had excellent outcome. Gross total resection is the standard primary treatment. Chemotherapy is the alternative standard treatment in incomplete resection cases, unresectable patients, or patients with progressive disease. Radiation therapy should be reserved as a salvage treatment option because of late complications that usually affect patients' quality of life.

Pediatric low-grade glioma: Targeted therapeutics and clinical trials in the molecular era

pLGGs are a group of tumors for which the era of molecular diagnostics has truly shifted treatment paradigms and patient care. The discovery that this group of tumors is driven by single-gene alterations/fusions in the MAPK pathway has resulted in relatively rapid translation into targeted therapy options for patients with this often chronic disease. This translation has been facilitated through efforts of multiple collaboratives and consortia and has led to the development of clinical trials testing the role of targeted therapies in pLGG. Although these developments represent promise, many questions remain regarding these therapies including their long-term toxicities and their potential effects on the natural history of pLGG.

Use of Trametinib in Children and Young Adults With Progressive Low-Grade Glioma and Glioneuronal Tumors

Low-grade gliomas/glioneuronal tumors comprise one-third of all pediatric-type CNS tumors. These tumors are generally caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway. Targeted drugs, such as trametinib, have shown promise in other cancers and are being utilized in low-grade gliomas. A retrospective chart review was conducted to evaluate radiographic response, visual outcomes, tolerability, and durability of response in progressive circumscribed low-grade gliomas treated with trametinib. Eleven patients were treated with trametinib. The best radiographic response was 2/11 partial response, 3/11 minor response, 3/11 stable disease, and 3/13 progressive disease. In the patients with partial or minor response, the best response was seen after longer durations of therapy; 4 of 5 best responses occurred after at least 9 months of therapy with a median of 21 months. Patients with optic pathway tumors showed at least stable vision throughout treatment, with 3 having improved vision on treatment. Trametinib is effective and well-tolerated in patients with progressive low-grade glioma. Best responses were seen after a longer duration of therapy in those with a positive response. Patients with optic pathway lesions showed stable to improved vision while on treatment.

Management of Optic Pathway Glioma: A Systematic Review and Meta-Analysis

Background: OPG accounts for 3−5% of childhood central nervous system (CNS) tumors and about 2% of pediatric glial lesions. Methods: Article selection was performed by searching PubMed, Web of Science, and Cochrane databases. Results: The pooled mortality rate was 0.12 (95%CI 0.09−0.14). Due to the unrepresentative data, improved and not changed outcomes were classified as favorable outcomes and worsened as unfavorable. Meta-analyses were performed to determine the rate of clinical and radiological favorable outcomes. In terms of visual assessment, the pooled rate of a favorable outcome in chemotherapy, radiotherapy, and surgery was 0.74, 0.81, and 0.65, respectively, and the overall pooled rate of the favorable outcome was 0.75 (95%CI 0.70−0.80). In terms of radiological assessment, the rate of a favorable outcome following chemotherapy, radiotherapy, and surgery was 0.71, 0.74, and 0.67, respectively, and the overall pooled rate of the favorable outcome is 0.71 (95%CI 0.65−0.77). The subgroup analysis revealed no significant difference in the rate of clinical and radiological favorable outcomes between the different treatment modalities (p > 0.05). Conclusion: Our analyses showed that each therapeutic modality represents viable treatment options to achieve remission for these patients.

Diencephalic Syndrome: A Rare Entity with Its Anaesthetic Management and Post-operative Complications of Diabetes Insipidus and Thrombocytopenia

Russell first described the diencephalic syndrome in 1951. It is a rare syndrome and usually presents in children as a cause of failure to thrive despite normal, or even increased appetite, with preservation of linear growth. The treatment options vary from endoscopic biopsy followed by chemotherapy to definitive surgical resection of the tumour. The authors here describe a case of an 8-year-old 10 kg emaciated child who presented with headache, vomiting, rage attacks, decreased weight, and diminution in vision. The child had bilateral optic atrophy; however, hormonal profiles were within normal limits. MRI of the brain gave an impression of craniopharyngioma.

Genetic Alteration Analysis of IDH1, IDH2, CDKN2A, MYB and MYBL1 in Pediatric Low-Grade Gliomas

Objective

To investigate pediatric low-grade gliomas for alterations in IDH1, IDH2, CDKN2A, MYB, and MYBL1.

Materials and Methods

DNA and RNA were extracted from 62 pediatric gliomas. Molecular methods included PCR, RT-PCR, and RNA sequencing; Sanger sequencing was used for validation.

Results

Analysis for hotspot genetic alterations in IDH1 R132 and IDH2 R172 (45 and 33 samples) was negative in all cases. CDKN2A deletions were detected in exons 1 and 2 in 1 (pleomorphic xanthoastrocytoma) sample of 9 samples analyzed. Of 10 samples analyzed for MYB translocation, 4 each were positive for translocations with exon 2 and exon 3 of PCDHGA1. Six samples showed MYBL rearrangement. The lack of IDH1/2 genetic alterations is in accordance with the literature in pediatric tumors. Alterations in MYB, MYBL were recently reported to characterize diffuse grade II, but not grade I, gliomas.

Conclusion

We optimized methods for analyzing gene variations and correlated the findings to pathological grade. The high incidence of MYB and MYBL need further evaluation. We also compared DNA, RNA, and RNA sequencing results for fusion, translocation, and genetic alterations. More accurate identification of the underlying biology of pediatric gliomas has implications for the development of targeted treatment.

The role of imaging features and resection status in the survival outcome of sporadic optic pathway glioma children receiving different adjuvant treatments

Optic pathway glioma (OPG) is a rare brain tumor affecting children, with no standard treatment strategy. This study described the sporadic OPG survival outcomes after surgical treatment and analyzed the role of imaging features and resection status in children receiving different adjuvant treatments. This retrospective study included 165 OPG patients whose clinical information were obtained from the hospital record system. Tumor volume and residual tumor volume were calculated by delineating the lesion area. Kaplan-Meier method and Cox proportional hazards model were conducted to analyze the independent prognosis factor. A total of 165 patients were included in this study. Respectively, the 5-year overall survival (OS) and progression-free survival (PFS) were 87.58% and 77.87%. Residual tumor size and first adjuvant treatment (AT) after surgery were both associated with PFS. In patients with small-size residual tumors, there was no significant difference in PFS between the AT treatment groups. Moreover, age, exophytic cystic components, leptomeningeal metastases, and AT were associated with OS. In patients with exophytic cystic components and those with leptomeningeal metastases, there was no significant difference in OS. Our results revealed that OPG patients could avoid or defer AT by maximized resection. Age ≤ 2 years was a disadvantageous factor for OS. Patients with exophytic cystic components were more likely to benefit from primary surgery, and CT or RT was not beneficial for these patients. Patients with leptomeningeal metastases had a poor prognosis regardless of the treatment they received. Future prospective clinical studies are needed to develop more effective treatment regimens.

Novel "T-Dimension" Therapies for Pediatric Optic Pathway Glioma: A Timely, Targeted, and Tailored Treatment Trend

INTRODUCTION

Novel targeted and tailored therapies can substantially improve the prognosis for optic pathway glioma (OPG), especially when implemented in a timely manner. However, their tremendous potential remains underestimated. Therefore, in this study, we provide an updated overview of the clinical trials, current trends, and future perspectives for OPG's novel therapeutic strategies.

METHODS

We completed an extensive literature review using the PubMed, MEDLINE, and ClinicalTrials.gov databases. We analyzed and reported the data following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Thioguanine, procarbazine, lomustine, and vincristine/vinblastine, as well as cisplatin-etoposide, provided excellent results in advanced-phase trials. Selumetinib and trametinib, two oral MEK inhibitors, have been approved for recurrent or refractory OPGs in association with the angiogenetic inhibitor bevacizumab. Among the mTOR inhibitors, everolimus and sirolimus showed the best results. Stereotactic radiosurgery and proton beam radiation therapy have advantages over conventional radiotherapy regimens. Timely treatment is imperative for acute visual symptoms with evidence of tumor progression. This latest evidence can help define a novel "T-Dimension" for pediatric OPG therapies.

CONCLUSION

The novel "T-Dimension" for pediatric OPGs is based on recent evidence-based treatments, including combination chemotherapy regimens, molecular targeted therapies, stereotactic radiosurgery, and proton beam radiation therapy. Additional clinical trials are essential for validating each of these new therapies.

Impact of systemic anticancer therapy in pediatric optic pathway glioma on visual function: A systematic review

Pediatric optic pathway glioma (OPG) can seriously decrease visual function in the case of progression. Systemic anticancer therapy (SAT) is considered the treatment of first choice for unresectable OPG. New SAT modalities for the treatment of progressive OPG have been introduced in the last decade, including VEGF and MAPK pathway inhibition. This systematic review evaluated the effect of SAT on change in visual acuity and visual field in OPG. A systematic review was performed on SAT for OPG (January 1990 to August 2020). MEDLINE and EMBASE (Ovid) were searched for studies reporting on change in visual acuity and visual field after treatment with SAT for OPG. Overall, 11 series, including 358 patients, fulfilled the eligibility criteria. After follow-up of median 3.7 years (range: cessation of SAT- 8.2 years), improvement in binocular VA was found in 0-45% of studies, stability in 18-77% and a decrease in 0-82%. Two studies reported on change in visual field (improvement in 19% and 71% of patients), although either the change was not defined or the testing strategy was lacking. Considerable heterogeneity was present among the included studies, such as variety in the combinations of SAT administered, status of neurofibromatosis type 1, definition regarding change in visual acuity, 1- or 2-eye analysis, diversity in anatomic location, and extent of follow-up, all of which made meta-analysis inappropriate. This systematic review suggests that the impact of SAT in OPG on visual function is still unclear. The wide ranges reported on the efficacy of SAT and the observed heterogeneity highlight the need for prospective studies with uniform definitions of outcome parameters.

High frequency of disease progression in pediatric spinal cord low-grade glioma (LGG): management strategies and results from the German LGG study group

BACKGROUND

Knowledge on management of pediatric spinal cord low-grade glioma (LGG) is scarce.

METHODS

We analyzed clinical datasets of 128 pediatric patients with spinal LGG followed within the prospective multicenter trials HIT-LGG 1996 (n = 36), SIOP-LGG 2004 (n = 56), and the subsequent LGG-Interim registry (n = 36).

RESULTS

Spinal LGG, predominantly pilocytic astrocytomas (76%), harbored KIAA1549-BRAF fusion in 14/35 patients (40%) and FGFR1-TACC1 fusion in 3/26 patients (12%), as well as BRAFV600E mutation in 2/66 patients (3%). 10-year overall survival (OS) and event-free survival (EFS) was 93% ± 2% and 38% ± 5%, respectively. Disseminated disease (n = 16) was associated with inferior OS and EFS, while age ≥11 years and total resection were favorable factors for EFS. We observed 117 patients following total (n = 24) or subtotal/partial resection (n = 74), biopsy (n = 16), or radiologic diagnosis only (n = 3). Eleven patients were treated first with chemotherapy (n = 9) or irradiation (n = 2). Up to 20.8 years after diagnosis/initial intervention, 73/128 patients experienced one (n = 43) or up to six (n = 30) radiological/clinical disease progressions. Tumor resections were repeated in 36 patients (range, 2-6) and 47 patients required nonsurgical treatment (chemotherapy, n = 20; radiotherapy, n = 10; multiple treatment lines, n = 17). Long-term disease control for a median of 6.5 (range, 0.02-20) years was achieved in 73/77 patients following one (n = 57) or repeated (n = 16) resections, and in 35/47 patients after nonsurgical treatment.

CONCLUSIONS

The majority of patients experienced disease progression, even after years. Multiple interventions were required for more than a third, yet multimodal treatment enabled long-term disease control. Molecular testing may reveal therapeutic targets.

Vision Outcomes for Pediatric Patients With Optic Pathway Gliomas Associated With Neurofibromatosis Type I: A Systematic Review of the Clinical Evidence

Children with neurofibromatosis type I (NF1) have a higher predisposition for low-grade astrocytomas of the optic pathway, commonly referred to as optic pathway gliomas (OPGs). OPGs can result in visual deterioration. Treatment outcomes in OPG-NF1 management are often reported around tumor stabilization. We sought to compare vision outcomes associated with different OPG treatment strategies to inform about this important functional metric. A meta-analysis exploring the different modalities to treat children with OPG-NF1 was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using multiple databases. Of the 113 articles identified in the search, 23 full text articles, representing 564 patients, were included for review. These articles included retrospective, prospective, and randomized controlled studies on observation (n=9), chemotherapy (n=19), radiation therapy (n=6), and surgery (n=7). Of the patients undergoing observation, 87% (60/69) demonstrated stable acuity. In the chemotherapy studies, 27.3% (72/264) demonstrated improved acuity/visual field and/or visual-evoked potential amplitudes, 39.4% (104/264) stable acuity, and 33.3% (88/264) deterioration. Both the radiation and surgical treatments reported worsening acuity at 90.9% (10/11) and 73.3% (11/15), respectively. Causal associations are not known. Indications for and timing of treatment choice warrant larger scale study to provide further understanding.

Rare Diseases of the Orbit

This article provides an overview of rare orbital diseases. Congenital malformations, inflammatory diseases, benign and malignant neoplasias are described. Although it represents a relatively small area of the body the orbit contains multiple different tissues. Therefore, a great variety of diseases can be found within the orbital space. That is the reason, why both the completeness and the level of detail in the description of particular diseases must be somewhat limited. Nevertheless, clinical manifestations, important aspects of diagnosis, treatment strategies, and, when specific data are available, the prognosis are described. The authors tried to highlight the most characteristic aspects of the different diseases to describe their relevant aspects in spite of the brevity of the subsections.

Evaluation of RAPNO criteria in medulloblastoma and other leptomeningeal seeding tumors using MRI and clinical data

BACKGROUND

Although the Response Assessment in Pediatric Neuro-Oncology (RAPNO) working group has made recommendations for response assessment in patients with medulloblastoma (MBL) and leptomeningeal seeding tumors, these criteria have yet to be evaluated.

METHODS

We examined MR imaging and clinical data in a multicenter retrospective cohort of 269 patients with MBL diagnoses, high grade glioma, embryonal tumor, germ cell tumor, or choroid plexus papilloma. Interobserver agreement, objective response (OR) rates, and progression-free survival (PFS) were calculated. Landmark analyses were performed for OR and progression status at 0.5, 1.0, and 1.5 years after treatment initiation. Cox proportional hazards models were used to determine the associations between OR and progression with overall survival (OS). Subgroup analyses based on tumor subgroup and treatment modality were performed.

RESULTS

The median follow-up time was 4.0 years. In all patients, the OR rate was .0.565 (95% CI: 0.505-0.625) by RAPNO. The interobserver agreement of OR determination between 2 raters (a neuroradiologist and a neuro-oncologist) for the RAPNO criteria in all patients was 83.8% (k statistic = 0.815; P < 0.001). At 0.5-, 1.0-, and 1.5-year landmarks, both OR status and PFS determined by RAPNO were predictive of OS (hazard ratios [HRs] for 1-year landmark: OR HR = 0.079, P < 0.001; PFS HR = 10.192, P < 0.001). In subgroup analysis, OR status and PFS were predictive of OS for all tumor subtypes and treatment modalities.

CONCLUSION

RAPNO criteria showed excellent consistency in the treatment response evaluation of MBL and other leptomeningeal seeding tumors. OR and PFS determined by RAPNO criteria correlated with OS.

Early radiotherapy preserves vision in sporadic optic pathway glioma

BACKGROUND

Sporadic optic pathway/hypothalamic gliomas represent a unique entity within pediatric low-grade glioma. Despite favorable survival, location makes treatment difficult and local progression debilitating. This study is a longitudinal assessment of visual acuity (VA) among children treated within the last 2 decades.

METHODS

Clinical characteristics were abstracted for patients treated from 2000 to 2018 at Texas Children's Cancer Center in Houston. Ophthalmologic data taken at 3- to 6-month intervals were examined with age-appropriate VA metrics converted to the LogMAR (logarithm of the minimum angle of resolution) scale. Kaplan-Meier blindness-free survival (BFS) curves, calculated as time-to-bilateral functional blindness (LogMAR ≥0.8 in both eyes), were calculated for patients receiving early radiation therapy (RT; upfront or as first-line salvage treatment) or chemotherapy (CT) and evaluated using the log-rank test.

RESULTS

Thirty-eight patients with a median follow-up of 8.5 years (range, 2-17 years) were identified. Median age at diagnosis was 3 years (interquartile range, <1-6 years). Early RT was administered in 11 patients (29%). Twenty-seven patients (71%) were treated primarily with CT, initiated at a median age of 3.5 years (range, <1-11 years). Eight patients in the CT group did eventually require RT secondary to VA loss and following multiple lines of CT. Median age at RT for all patients was 11 years (range, 3-17 years). BFS rates were 81% at 5 years and 60% at 8 years for CT and 100% at 5 and 8 years for early RT (P = .017).

CONCLUSIONS

In a contemporary cohort, early RT, defined as initial or first-line salvage therapy, was found to have superior BFS for appropriately selected patients with sporadic optic pathway/hypothalamic gliomas.

LAY SUMMARY

Children with low-grade brain tumors of the optic pathway generally have excellent long-term survival; however, given the location of these tumors, there can commonly be threatened vision if the tumor grows. Although radiation is generally deferred in children on the basis of legitimate concerns regarding the effects on the developing brain, it may represent a vision-preserving therapy for well-selected older patients.

Phase I study of vinblastine in combination with nilotinib in children, adolescents, and young adults with refractory or recurrent low-grade glioma

Background

New rescue regimens are needed for pediatric refractory/recurrent low-grade glioma. Nilotinib is a tyrosine kinase inhibitor that has potential synergistic effects with vinblastine on angiogenesis, tumor cell growth, and immunomodulation.

Methods

This phase I trial aimed to determine the recommended doses of this combination for phase II trials (RP2D) using the dual-agent Bayesian continual reassessment method. Nilotinib was given orally twice daily (BID) in combination with once-weekly vinblastine injections for a maximum of 12 cycles of 28 days (clinicaltrials.gov, NCT01884922).

Results

Thirty-five pediatric patients were enrolled across 4 dose levels. The median age was 7 years and 10 had neurofibromatosis type 1. Patients had received a median of 3 prior treatment lines and 25% had received more than 4 previous treatment lines. Dose-limiting toxicity (DLT) during cycle 1 was hematologic, dermatologic, and cardiovascular. The RP2D was identified at 3 mg/m² weekly for vinblastine with 230 mg/m² BID for nilotinib (estimated probability of DLT = 18%; 95% credibility interval, 7-29%). Fifteen patients completed the 12 cycles; 2 stopped therapy prematurely due to toxicity and 18 due to disease progression. Three patients achieved a partial response leading to an objective response rate of 8.8% (95% confidence interval [CI], 1.9-23.7), and the disease control rate was 85.3% (95% CI, 68.9-95.1). The 12-month progression-free survival was 37.1% (95% CI, 23.2-53.67).

Conclusions

Vinblastine and nilotinib combination was mostly limited by myelosuppression and dermatologic toxicity. The efficacy of the combination at the RP2D is currently evaluated in a randomized phase II trial comparing this regimen to vinblastine alone.

Efficacy and safety of bevacizumab in progressive pediatric low-grade glioma: a systematic review and meta-analysis of outcome rates

Background

Successful management of pediatric low-grade glioma (pLGG) can be complicated by eloquent anatomical location, as well as specific pathologic and molecular features. Some authors have proposed using the VEGF inhibitor bevacizumab to improve disease control, but its safety and efficacy are poorly defined. Correspondingly, our aim was to pool systematically identified clinical data in the literature to assess the clinical utility of bevacizumab for pLGG at progression.

Methods

A systematic search of 7 electronic databases from inception to June 2019 was conducted following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Articles were screened against prespecified criteria. Outcomes were then pooled by random-effects meta-analyses of proportions.

Results

Seven pertinent studies described the outcomes of 110 progressive pLGG patients managed with bevacizumab in largely multiagent regimens. While on treatment, the rate of clinical response was 58% (95% CI, 43%-72%), and the rate of response on imaging was 80% (95% CI, 58%-96%). The rate of grade 3 or higher toxicity was 8% (95% CI, 2%-17%), with proteinuria the most commonly described. In the off-treatment period up to median 1 year, the rate of progression was estimated to be 51% (95% CI, 28%-74%).

Conclusions

Bevacizumab has the potential to control clinical and radiographic disease with relatively low grade 3 or higher toxicity risk in progressive pLGG patients. However, the long-term off-treatment benefits of this therapy are not yet well defined. Heterogeneity in the literature precludes any formal recommendations regarding its use until larger, more standardized investigations can be performed.

Current concepts in radiologic assessment of pediatric brain tumors during treatment, part 1

Pediatric brain tumors differ from those in adults by location, phenotype and genotype. In addition, they show dissimilar imaging characteristics before and after treatment. While adult brain tumor treatment effects are primarily assessed on MRI by measuring the contrast-enhancing components in addition to abnormalities on T2-weighted and fluid-attenuated inversion recovery images, these methods cannot be simply extrapolated to pediatric central nervous system tumors. A number of researchers have attempted to solve the problem of tumor assessment during treatment in pediatric neuro-oncology; specifically, the Response Assessment in Pediatric Neuro-Oncology (RAPNO) working group was recently established to deal with the distinct challenges in evaluating treatment-related changes on imaging, but no established criteria are available. In this article we review the current methods to evaluate brain tumor therapy and the numerous challenges that remain. In part 1, we examine the role of T2-weighted imaging and fluid-attenuated inversion recovery sequences, contrast enhancement, volumetrics and diffusion imaging techniques. We pay particular attention to several specific pediatric brain tumors, such as optic pathway glioma, diffuse midline glioma and medulloblastoma. Finally, we review the best means to assess leptomeningeal seeding.

Pediatric low-grade gliomas: next biologically driven steps

Despite the fact that they are not typically life-threatening, low-grade gliomas (LGGs) remain a significant clinical challenge in pediatric neuro-oncology due to comorbidities associated with these tumors and/or their treatments, and their propensity to multiply recurs. LGGs, in total the most common brain tumors arising in childhood, can often become a chronic problem requiring decades of management. The Second International Consensus Conference on Pediatric Low-Grade Gliomas held in Padua, Italy in 2016 was convened in an attempt to advance the pace of translating biological discoveries on LGGs into meaningful clinical benefit. Topics discussed included: the implications of our growing biological understanding of the genomics underlying these tumors; the assessment of the model systems available; the implications of the molecular and histopathologic differences between adult and pediatric diffuse gliomas; and steps needed to expedite targeted therapy into late-stage clinical trials for newly diagnosed cases. Methods for the diagnostic assessment of alterations in the Ras/mitogen-activated protein kinase pathway, typical for these tumors, were also considered. While the overall tone was positive, with a consensus that progress is being and will continue to be made, the scale of the challenge presented by this complex group of tumors was also acknowledged. The conclusions and recommendations of the meeting panel are provided here as an outline of current thinking and a basis for further discussion.

Pediatric Optic Pathway/Hypothalamic Glioma

Optic pathway/hypothalamic gliomas (OP/HGs) are rare astrocytic tumors that appear more commonly among young children and often are unresectable. They comprise approximately 2% of all central nervous system tumors and account for 3–5% of pediatric intracranial tumors. Initial manifestations are often visual disturbances, endocrinopathies and hypothalamic dysfunction such as the diencephalic syndrome, and sometimes hydrocephalus due to cerebrospinal fluid (CSF) outflow obstruction. In many cases, the tumors are diagnosed late in the clinical course because they silently enlarge. These tumors consist mostly of histologically benign, World Health Organization (WHO) grade I tumors represented by pilocytic astrocytomas (PA), the rest being pilomyxoid astrocytomas (PXA) – WHO grade II tumors. In young pediatric patients, however, can be seen PXA that show aggressive clinical course such as CSF dissemination. Our small series of 14 non-Neurofibromatosis type 1 (NF-1) OP/HGs PA patients underwent extended resection without any adjuvant treatments. The median age at initial treatment was 11.5 ± 6.90 years (range, 1–25 years) and median follow up 85.5 ± 25.0 months. Surgical resection for OP/HGs results in acceptable middle-term survival, tumor control and functional outcome equivalent to chemotherapy. There is, however, no longer doubt that chemotherapy with or without biopsy and as-needed debulking surgery remains the golden standard in management of OP/H. Clinical conditions and treatment plans for OP/HGs vary depending on their structure of origin.

Postoperative functional status in patients with supratentorial superficial low-grade glioma

Background

We investigated the functional status of adult supratentorial superficial low-grade glioma (ASS-LGG) after surgery and analyzed its relevant factors to guide the therapeutic strategy and improve the life quality of these patients.

Methods

Clinical materials from January 2008 to December 2010 in 104 adults with ASS-LGG were analyzed retrospectively. The follow-up period ranged from 6 months to 1.5 years. The logistic regression was used to evaluate the preoperative and postoperative variation of functional status in patients to disclose the relevant factors affecting postoperative functional status, such as age, gender, the duration of symptom, size and location of the tumor, hemisphere, resection degree, and tumor pathologic grade and preoperative Karnofsky performance status (Pre-KPS).

Results

Four out of nine candidate factors are related to the postoperative functional status. They are age less than 40 years, the size of tumor less than 5 cm in diameter, tumor located in the right hemisphere, and limited resection of tumor in the eloquent area.

Conclusions

It seems more meaningful to evaluate the functional status of the patients with ASS-LGG on the basis of these clinical features, involving age, tumor size, location, and extent of resection.

Analysis of Survival Prognosis for Children with Symptomatic Optic Pathway Gliomas Who Received Surgery

OBJECTIVE

The feasibility and prognosis of surgical treatment for children with optic pathway gliomas (OPGs) is controversial. Therefore this study attempted to evaluate the effects of surgery and discuss prognostic factors related to the survival of children with symptomatic OPGs.

MATERIALS AND METHODS

One-hundred twenty-five children diagnosed with OPGs underwent surgery in the Department of Neurosurgery, Beijing Tiantan Hospital from 2003-2016. In this retrospective study, their demographics, clinical characteristics, treatments, and survival outcomes were investigated and summarized.

RESULTS

Among the 125 patients, the 5-year overall survival (OS) rate and progression-free survival (PFS) rate were 84.1% and 70.6%, respectively. In the univariate analysis, patients who received postoperative radiotherapy (RT) after surgery had significantly better 5-year OS and PFS rates than patients who did not receive RT (P < 0.001 for both comparisons), patients who were 3 years old had better PFS rates than younger patients (P < 0.001), and patients with endocrinology symptoms had significantly worse PFS rates than patients with other symptoms (P = 0.049). In the multiple regression analysis, postoperative treatment with RT and tumors with a lower pathologic grade were better predictors of OS. An age older than 3 years and postoperative treatment with RT were better predictors of PFS.

CONCLUSIONS

Surgery is safe and feasible for children with large volumes of OPGs and symptoms of functional impairment and obstructive hydrocephalus. Furthermore, adjuvant RT after surgery may significantly improve OS and PFS. The pathologic grade is an independent prognostic factor for OS, and the age at diagnosis is an independent prognostic factor for PFS.

Rechallenge to Carboplatin in Children with Low Grade Glioma and Carboplatin Hypersensitivity Reactions

Background: Carboplatin based regimens have demonstrated activity in pediatric patients with low grade gliomas (LGG). However, carboplatin hypersensitivity reactions (CHRs) may be a major problem leading to premature cessation of an effective therapy. The objectives of this study were to describe the prevalence, characteristics and management of CHR.

Methods: We performed a retrospective review of children with LGG treated between January 1994 and July 2015 with carboplatin and vincristine who had a documented CHR. We identified two groups: the first was treated following the schema proposed by Packer et al., and re-exposed to carboplatin using a desensitization protocol; the second was treated according to protocol SIOP LGG 2004 and re-exposed with the infusion time prolonged.

Results: CHRs were observed in 16 patients (34%) out of 47. Hypersensitivity reactions occurred in 6 patients (20.7%) of the first, and 10 patients (55.5%) of the second group, respectively. The grade 2 reactions were the most common. The median number of carboplatin doses administered at the first episode of CHR was 7 (range, 3–9) for the first group, and 8.5 (range, 5–11) for the second, respectively. Six patients were re-exposed to carboplatin using a desensitization protocol; 10 with a prolonged infusion time. Overall success rate for re-exposition was 43.75% (100% and 10%, respectively) (P = 0.001).

Conclusions: Our results show that re-exposure is a safe alternative to abandoning carboplatin. Desensitization showed greater effectiveness compared to a prolonged infusion time, which allowed the patients to receive effective treatment without adverse reactions.

Pediatric Suprasellar Tumors

The various childhood suprasellar tumors, while pathologically distinct, present similar clinical and surgical challenges as a result of their common anatomic location. These lesions are in close proximity to or may invade the optic nerve and chiasm, pituitary gland and infundibulum, hypothalamus, and third ventricle, leading to presenting features including visual field loss, impairment in visual acuity, endocrine dysfunction, and hydrocephalus. Though many suprasellar lesions are relatively benign in pathology, treatment may be complicated by high surgical morbidity resulting from damage to the hypothalamic-pituitary axis. Here we review the most frequent pediatric lesions occurring in the suprasellar region: craniopharyngioma, chiasmatic glioma, germ cell tumor, Rathke cleft and arachnoid cysts, pituitary adenoma, and histiocytosis. This review outlines both common presenting features and differentiating aspects of these lesions. It also includes classic radiographic presentations and treatment considerations for each lesion.

Platinum-induced hearing loss after treatment for childhood cancer

BACKGROUND

Platinum-based therapy, including cisplatin, carboplatin, oxaliplatin or a combination of these, is used to treat a variety of paediatric malignancies. Unfortunately, one of the most important adverse effects is the occurrence of hearing loss or ototoxicity. There is a wide variation in the reported prevalence of platinum-induced ototoxicity and the associated risk factors. More insight into the prevalence of and risk factors for platinum-induced hearing loss is essential in order to develop less ototoxic treatment protocols for the future treatment of children with cancer and to develop adequate follow-up protocols for childhood cancer survivors treated with platinum-based therapy.

OBJECTIVES

To evaluate the existing evidence on the association between childhood cancer treatment including platinum analogues and the occurrence of hearing loss.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 8), MEDLINE (PubMed) (1945 to 23 September 2015) and EMBASE (Ovid) (1980 to 23 September 2015). In addition, we searched reference lists of relevant articles and the conference proceedings of the International Society for Paediatric Oncology (2008 to 2014), the American Society of Pediatric Hematology/Oncology (2008 to 2015) and the International Conference on Long-Term Complications of Treatment of Children and Adolescents for Cancer (2010 to 2015). Experts in the field provided information on additional studies.

SELECTION CRITERIA

All study designs, except case reports, case series (i.e. a description of non-consecutive participants) and studies including fewer than 100 participants treated with platinum-based therapy who had an ototoxicity assessment, examining the association between childhood cancer treatment including platinum analogues and the occurrence of hearing loss.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the study selection. One review author performed data extraction and risk of bias assessment, which was checked by another review author.

MAIN RESULTS

We identified 13 eligible cohort studies including 2837 participants with a hearing test after treatment with a platinum analogue for different types of childhood cancers. All studies had methodological limitations, with regard to both internal (risk of bias) and external validity. Participants were treated with cisplatin, carboplatin or both, in varying doses. The reported prevalence of hearing loss varied considerably between 0% and 90.1%; none of the studies provided data on tinnitus. Three studies reported a prevalence of 0%, but none of these studies provided a definition for hearing loss and there might be substantial or even complete overlap in included participants between these three studies. When only studies that did provide a definition for hearing loss were included, the prevalence of hearing loss still varied widely between 1.7% and 90.1%. All studies were very heterogeneous with regard to, for example, definitions of hearing loss, used diagnostic tests, participant characteristics, (prior) anti-tumour treatment, other ototoxic drugs and length of follow-up. Therefore, pooling of results was not possible.Only two studies included a control group of people who had not received platinum treatment. In one study, the prevalence of hearing loss was 67.1% (95% confidence interval (CI) 59.3% to 74.1%) in platinum-treated participants, while in the control participants it was 7.4% (95% CI 6.2% to 8.8%). However, hearing loss was detected by screening in survivors treated with platinum analogues and by clinical presentation in control participants. It is uncertain what the effect of this difference in follow-up/diagnostic testing was. In the other study, the prevalence of hearing loss was 20.1% (95% CI 17.4% to 23.2%) in platinum-treated participants and 0.4% (95% CI 0.12% to 1.6%) in control participants. As neither study was a randomized controlled trial or controlled clinical trial, the calculation of a risk ratio was not feasible as it is very likely that both groups differed more than only the platinum treatment.Only two studies evaluated possible risk factors using multivariable analysis. One study identified a significantly higher risk of hearing loss in people treated with cisplatin 400 mg/m(2) plus carboplatin 1700 mg/m(2) as compared to treatment with cisplatin 400 mg/m(2) or less, irrespective of the definition of hearing loss. They also identified a significantly higher risk of hearing loss in people treated with non-anthracycline aminoglycosides antibiotics (using a surrogate marker) as compared to people not treated with them, for three out of four definitions of hearing loss. The other study reported that age at treatment (odds ratio less than 1 for each single-unit increase) and single maximum cisplatin dose (odds ratio greater than 1 for each single-unit increase) were significant predictors for hearing loss, while gender was not.

AUTHORS' CONCLUSIONS

This systematic review shows that children treated with platinum analogues are at risk for developing hearing loss, but the exact prevalence and risk factors remain unclear. There were no data available for tinnitus. Based on the currently available evidence we can only advise that children treated with platinum analogues are screened for ototoxicity in order to make it possible to diagnose hearing loss early and to take appropriate measures. However, we are unable to give recommendations for specific follow-up protocols including frequency of testing. Counselling regarding the prevention of noise pollution can be considered, such as the use of noise-limiting equipment, avoiding careers with excess noise and ototoxic medication. Before definitive conclusions on the prevalence and associated risk factors of platinum-induced ototoxicity can be made, more high-quality research is needed. Accurate and transparent reporting of findings will make it possible for readers to appraise the results of these studies critically.

Prechiasmatic transection of the optic nerve in optic nerve glioma: technical description and surgical outcome

Optic pathway glioma (OPG) encompasses a spectrum of findings ranging from lesions confined to the optic nerve only, lesions affecting the optic chiasm and hypothalamus, and lesions with diffuse involvement of a large part of the optic pathway and neighboring structures. The majority of pediatric low-grade astrocytomas in the optic/chiasmatic region are typical pilocytic astrocytoma. The rest of them (10 %) may be other gliomas such as fibrillary pilomyxoid astrocytoma (grade 2 WHO). The postsurgical local recurrence rate of 55 to 76 % has been reported in some histological subtypes such as pilomyxoid astrocytoma (grade 2). Performing a prechiasmatic transection might offer a new surgical option to avoid further tumor growth toward the chiasm in the optic nerve glioma with predominantly orbital manifestations. In this retrospective study, four patients (three children, two without neurofibromatosis type 1 (NF1), and one with NF1 and one adult without NF1) with optic nerve glioma without involvement of the chiasm but blindness, disfiguring proptosis, and pain of the affected eye were included. The surgical approach was performed as a combined approach from pterional extradural and intradural. Without any exceptions, vision of the contralateral eye could be preserved and did not show any deterioration after surgery or during the follow-up time between 17 and 106 months. Furthermore, in all patients, gross total tumor resection could be achieved. During follow-up observation in all patients, no further tumor progress or recurrences could be observed. None of the patients were treated postoperatively by radiotherapy or chemotherapy. Prechiasmatic transection of the optic nerve in optic nerve glioma without affecting the chiasm might offer a surgical treatment option to control tumor growth and to preserve vision of the contralateral eye.

Neurofibromatosis type 1 associated low grade gliomas: A comparison with sporadic low grade gliomas

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder, associated with a variable clinical phenotype including café-au-lait spots, intertriginous freckling, Lisch nodules, neurofibromas, optic pathway gliomas and distinctive bony lesions. NF1 is caused by a mutation in the NF1 gene, which codes for neurofibromin, a large protein involved in the MAPK- and the mTOR-pathway through RAS-RAF signalling. NF1 is a known tumour predisposition syndrome, associated with different tumours of the nervous system including low grade gliomas (LGGs) in the paediatric population. The focus of this review is on grade I pilocytic astrocytomas (PAs), the most commonly observed histologic subtype of low grade gliomas in NF1. Clinically, these PAs have a better prognosis and show different localisation patterns than their sporadic counterparts, which are most commonly associated with a KIAA1549:BRAF fusion. In this review, possible mechanisms of tumourigenesis in LGGs with and without NF1 will be discussed, including the contribution of different signalling pathways and tumour microenvironment. Furthermore we will discuss how increased understanding of tumourigenesis may lead to new potential targets for treatment.

Optic pathway glioma in children: 10 years of experience in a single institution

Optic pathway glioma (OPG) is a rare brain tumor that occurs more commonly during early childhood and is frequently associated with neurofibromatosis type 1 (NF1). In this study, our aim was to describe the characteristics, management, and outcome of patients with OPG. We retrospectively analyzed the clinical charts of all children diagnosed with OPG at our institution from 2003 to 2013. Twenty children (11 boys and 9 girls, median age: 5 and 3/12 years; NF1: 15/20) were diagnosed with OPG. The diagnosis was based on magnetic resonance imaging (MRI) findings. A biopsy was useful in 3 patients. The main reason for seeking medical advice was decreased vision (7/20 patients), whereas in 10/20 patients, the diagnosis was established during the routine follow-up for their NF1. Fifteen patients demonstrated MRI findings of optic nerve involvement and/or chiasmal tumor, whereas in 5 children, postchiasmal structures were also involved. Sixteen patients (16/20) received carboplatin-based regimens, whereas 4/20 patients were only under close observation. Six patients showed deterioration of visual acuity and/or imaging findings at the end of treatment and/or during their follow-up. Three of them (3/6) underwent tumor resection, whereas 1 (1/6) received radiation treatment. None of our patients had total blindness from both eyes. Half of our patients were diagnosed during follow-up for their NF1, the incidence of which was high in our group. Our data suggest that chemotherapy helps in the preservation of vision in the majority of children.

Metastatic Low-Grade Gliomas in Children: 20 Years' Experience at St. Jude Children's Research Hospital

BACKGROUND

Patients with low-grade gliomas (LGG), which are the most common childhood brain tumors, have excellent long-term survival. Dissemination of LGG is rare. Robust data on the incidence, presentation, patterns of dissemination, disease behavior, outcome, and best-management approaches do not exist. We describe 20 years of follow-up of children with metastatic LGG.

PROCEDURE

Data collected during the period 1990-2010 were retrospectively reviewed for the following inclusion criteria: diagnosis of metastatic LGG, age younger than 21 years at initial diagnosis, and magnetic resonance imaging of the brain and/or spine at diagnosis and/or follow-up. Patient demographics, pathology, treatment modalities, and outcome were reviewed.

RESULTS

Of 599 patients with LGG, 38 (6%) had metastatic disease at either diagnosis or follow-up. Most tumors (87%) were located in the brain, and half of the patients had metastatic disease at presentation. The most common diagnosis was pilocytic astrocytoma (55%). Chemotherapy was the most common initial treatment modality. Median survival of the group was 6.2 years (range, 0.1-16.9 years). Fifteen (40%) patients died at a median of 6 years from diagnosis (range, 0.8-15 years). Overall survival at 5, 10, and 15 years was 80.7 ± 6.6%, 63.0 ± 10.2%, and 50.9 ± 16.0%, respectively.

CONCLUSION

This study describes the longest follow-up of children with metastatic LGG. LGG is underestimated and entails major morbidity and mortality. Prospective studies are needed to learn the true incidence, study the biology, and determine the best approaches to diagnosis, treatment, and follow-up.

Optic Pathway Gliomas: Clinical Manifestation, Treatment, and Follow-Up

OBJECTIVE

Optic pathway gliomas (OPG) are infrequent pediatric brain tumors that affect the optic nerve and the visual pathway in the brain. A wide spectrum of signs and symptoms, such as visual impairment, nystagmus, proptosis, and visual loss, may occur at different stages. Other manifestations, such as hydrocephalus, diancephalic syndrome, neurologic deficits, and growth and developmental delays, may be present as well. Surgical resection, chemotherapy, and radiotherapy are used as treatment strategies. The purpose of this study is to evaluate the clinical presentation of OPG patients and their final outcomes in response to treatment.

METHODS

Thirty-seven patients with an initial diagnosis of OPG were studied as part of a single-center retrospective cohort for their clinical presentation, treatment, and response to treatment over a 10-year period.

RESULTS

The mean age of the patients was 37.1 months, and there was a nearly equal sex distribution. The most prevalent manifestation was visual impairment (94.4%), and other symptoms included nystagmus (50%), growth and developmental delays (27.8%), neurological deficits (19.4%), diencephalic syndrome (13.5%), proptosis (11.1%), and hydrocephalus (29.7%). Tumor staging revealed that 10.8% of the cases were stage A, 54.1% were stage B, and 35.1% were stage C. In 30 evaluable patients, the response to treatment included complete response (CR; 23.3%), partial response (PR; 43.3%), stable disease (23.3%), progressive disease (3.3%), and death due to disease (6.7%). A significant association was detected between tumor staging and the response to treatment, with higher rates of CR and PR in stage B and a higher mortality rate in stage C (p = 0.005).

CONCLUSION

OPG occur more commonly in the first decade of life, with visual disturbance as the most prevalent symptom. Tumor staging and the treatment strategy are proposed to affect the response to treatment, although the specific tumor behavior in each patient should be considered as well.

Differences in the clinical courses of pediatric and adult pilocytic astrocytomas with progression: a single-institution study

PURPOSE

Pilocytic astrocytoma (PA) is a World Health Organization grade I neoplasm that generally follows a benign course. However, in some patients, PA exhibits an aggressive clinical course. Here, we examined the clinical course of pediatric and adult PAs with progression at a single institution.

METHODS

Between 1995 and 2013, 39 patients with PA were treated. Nineteen were pediatric patients (mean age, 12 years; range, 1-17 years) with a male-to-female patient ratio of 10:9, while 20 were adults (mean age, 36.4 years; range, 19-65 years) with a male-to-female ratio of 9:11. We analyzed and compared tumor location, extent of tumor resection, adjuvant treatment, and clinical course in all patients.

RESULTS

In the 19 pediatric patients, tumors were located in the cerebellar vermis, cerebellar hemisphere, optic pathways plus hypothalamus, hypothalamus, brainstem, and the temporal lobe in 6 (31.6%), 5 (26.3%), 3 (15.8%), 2 (10.5%), and 2 (10.5%) patients and 1 (5.3%) patient, respectively. The mass was totally, subtotally, or partially resected in 11 (57.9%), 2 (10.5%), and 4 (21.1%) patients, respectively; biopsies were performed in 2 (10.5%) patients. Immediate postoperative adjuvant treatment was carried out in 6 patients. Tumor progression was detected in 3 patients at 3.0, 4.6, and 5.2 years after treatment, respectively, without significant symptoms. In the 20 adult patients, tumors were located in the cerebellar hemisphere, cerebellar vermis, hypothalamus, brainstem, cerebral hemisphere, and lateral ventricle in 5 (25%), 4 (20%), 3 (15%), 3 (15%), 3 (15%), and 2 (10%) patients, respectively. The mass was totally, subtotally, or partially resected in 11 (55%) and 6 (30%) patients and 1 (5%) patient, respectively; biopsies were performed in 2 patients. Immediate adjuvant treatment was carried out in 2 patients. Progression was detected in 3 patients at 0.3, 0.9, and 2.5 years after treatment, respectively, with progressive neurologic symptoms. There was one case of disease-related mortality during follow-up among the adult patients.

CONCLUSION

Most of the PA cases evaluated in this study were benign. However, tumor progression in adult PAs followed a more aggressive clinical course than those in pediatric PAs.

Mortality in Children with Optic Pathway Glioma Treated with Up-Front BB-SFOP Chemotherapy

BACKGROUND

In terms of overall survival (OS), limited data are available for the very long-term outcomes of children treated for optic pathway glioma (OPG) with up-front chemotherapy. Therefore, we undertook this study with the aim of clarifying long-term OS and causes of death in these patients.

METHODS

We initiated and analyzed a historical cohort study of 180 children with OPG treated in France with BB-SFOP chemotherapy between 1990 and 2004. The survival distributions were estimated using Kaplan-Meier method. The effect of potential risk factors on the risk of death was described using Cox regression analysis.

RESULTS

The OS was 95% [95% CI: 90.6-97.3] 5 years after diagnosis and significantly decreased over time without ever stabilizing: 91.6% at 10 years [95% CI: 86.5-94.8], 80.7% at 15 years [95% CI: 72.7-86.8] and 75.5% [95% CI: 65.6-83] at 18 years. Tumor progression was the most common cause of death (65%). Age and intracranial hypertension at diagnosis were significantly associated with a worse prognosis. Risk of death was increased by 3.1[95% CI: 1.5-6.2] (p=0.002) for patients less than 1 year old at diagnosis and by 5.2[95% CI: 1.5-17.6] (p=0.007) for patients with initial intracranial hypertension. Boys without diencephalic syndrome had a better prognosis (HR: 0.3 [95% CI: 0.1-0.8], p=0.007).

CONCLUSIONS

This study shows that i) in children with OPG, OS is not as favorable as previously described and ii) patients can be classified into 2 groups depending on risk factors (age, intracranial hypertension, sex and diencephalic syndrome) with an OS rate of 50.4% at 18 years [95% CI: 31.4-66.6] in children with the worst prognosis. These findings could justify, depending on the initial risk, a different therapeutic approach to this tumor with more aggressive treatment (especially chemotherapy) in patients with high risk factors.

[Pediatric intracranial tumors : Principles of diagnostics and treatment]

Pediatric intracranial tumors account for approximately 24% of childhood malignancies. Pathological entities and their frequencies differ significantly from adult intracranial tumors and have age-specific differences in the pediatric population itself. In Germany treatment and diagnosis must be carried out according to ongoing multicenter trials for therapy optimization and registers of the Gesellschaft für pädiatrische Onkologie und Hämatologie (GPOH, Society of Pediatric Oncology and Hematology) in specialized centers for pediatric oncology. In addition to the articles in this issue which focus on the radiological aspects of the different entities, this article provides an overview of the principles of diagnostics and treatment of pediatric intracranial tumors.

Manifestations of pilocytic astrocytoma: a pictorial review

BACKGROUND

Pilocytic astrocytoma can be challenging to diagnose.

METHODS

Its clinical presentations can differ, directly related to its size and location, and are relatively unreliable. Similarly, imaging findings also vary with the location of the pilocytic astrocytoma.

RESULTS

This review provides an overview of the different imaging findings regarding pilocytic astrocytomas using both conventional and advanced magnetic resonance imaging sequences according to tumour location; the findings are strongly related to the tumour's tendency to infiltrate surrounding structures, being able to carry out gross total resection, and finally the prognosis.

CONCLUSIONS

Knowledge of these imaging manifestations of pilocytic astrocytoma may be helpful to arrive at an accurate diagnosis.

TEACHING POINTS

• To recognise the various imaging findings of pilocytic astrocytoma on both conventional and advanced magnetic resonance imaging sequences. • To identify the characteristic imaging findings according to tumour location. • To discuss the relevant differential diagnoses of pilocytic astrocytoma in each tumour location.

Children <1 year show an inferior outcome when treated according to the traditional LGG treatment strategy: a report from the German multicenter trial HIT-LGG 1996 for children with low grade glioma (LGG)

BACKGROUND

Children diagnosed with LGG at an age <1 year are reported to have an impaired prognosis in comparison to older patients. Analysis of this subgroup could reveal the necessity to develop risk-adapted treatment approaches.

PROCEDURE

Children <1 year at diagnosis (n = 66, median age 7.3 months, 33 female, none NFI) from the HIT-LGG 1996 cohort were analyzed for risk factors for EFS, PFS and OS. Several children suffered from diencephalic syndrome (DS, n = 22) and primary dissemination (DLGG, n = 9), 50 had a supratentorial midline (SML) location. Extent of resection was complete/subtotal in 12, partial in 15, biopsy in 27. Tumors were pilocytic astrocytoma WHO grade I (n = 33), other WHO grade I (n = 14), pilomyxoid astrocytomas WHO grade II (n = 3), and neuroepithelial tumors WHO grade II (n = 4).

RESULTS

One-year EFS was 34.8%. SML-localisation, minor extent of surgery, pilocytic astrocytoma, DLGG and DS were unfavorable predictive factors. No additional non-surgical therapy was applied in 24, 36 were treated with VCR/carboplatin chemotherapy, 6 with radiotherapy (5/6 brachytherapy). Ten-year-PFS-rate following non-surgical therapy was 16.7%; DS and DLGG were unfavorable factors. Ten-year-OS-rate was 72.8%, lower for children <6 months at diagnosis, with DS, or with DLGG. At last follow up in August 2011, vision in 31 living children was often severely impaired.

CONCLUSIONS

Children <1 year at diagnosis have a conspicuously impaired survival with current treatment approaches. Age <6 months, diencephalic syndrome and dissemination constitute risk factors for even lower PFS and OS. Treatment adaptations are needed to improve outcome and molecular genetics may explain tumor aggressiveness.

Pediatric low-grade gliomas: how modern biology reshapes the clinical field

Low-grade gliomas represent the most frequent brain tumors arising during childhood. They are characterized by a broad and heterogeneous group of tumors that are currently classified by the WHO according to their morphological appearance. Here we review the clinical features of these tumors, current therapeutic strategies and the recent discovery of genomic alterations characteristic to these tumors. We further explore how these recent biological findings stand to transform the treatment for these tumors and impact the diagnostic criteria for pediatric low-grade gliomas.

[Orbital neoplasia. Part I: Introduction, vascular and neurogenic tumors]

Tumors of the orbit are rare but the huge variability of clinical symptoms and findings are challenging for the ophthalmologist who is frequently contacted as the first resort. If the patient history and clinical findings are suspicious for an orbital mass the result of the initial examination should allow a rough estimation of localization (intra/extraconal), type of growth (expansive/infiltrative), dignity (vascular/solid etc.) and threat to visual functions. An adequate initial diagnostic pathway enables a precise question to the radiologist to be formulated and selection of the disciplines required for an interdisciplinary workup and therefore for early treatment.

Preclinical evaluation of dipotassium bisperoxo (picolinato) oxovanadate V for the treatment of pediatric low-grade gliomas

AIM

The treatment of pediatric low-grade gliomas with current treatment modalities still remains ineffective among a subset of patients; hence, justifying the need to further investigate more effective therapies. Dipotassium bisperoxo (picolinato) oxovanadate V (Bpv[pic]), is a derivative of the trace metal vanadium and a potent inhibitor of protein tyrosine phosphatases, which are important mediators of oncogenic and tumor suppressive activities in cancers. In this study, we undertook a preclinical evaluation of the antineoplastic functions of Bpv(pic) in the treatment of pediatric low-grade gliomas.

MATERIALS & METHODS

We utilized pediatric low-grade glioma cell lines (Res186, Res259 and R286) in a wide variety of cancer assays to determine whether Bpv(pic) can abrogate the neoplastic properties of these cells.

RESULTS

Our preclinical evaluation of the antineoplastic properties of Bpv(pic) in pediatric low-grade gliomas reveals a significant dose-dependent decrease in cell viability as a consequence of decreased proliferation and sustained induction of growth arrest and apoptosis. Bpv(pic) significantly decreases cell migration/invasion and anchorage-independent growth in soft agarose. Within cells, Bpv(pic) functions by attenuating CDC25A activity, and by decreasing the expression of multiple protein tyrosine phosphatases, DNA repair genes, microtubule-associated genes, such as PLK1, AURKA and HDAC6, and conversely augmenting the expression of proapoptotic mediators such as BAK, AIFM and CTSL1.

CONCLUSION

Collectively, our data strongly suggest novel evidence of Bpv(pic) being a potent antineoplastic drug and a suitable alternative for the treatment of pediatric low-grade gliomas.

Challenges with defining response to antitumor agents in pediatric neuro-oncology: a report from the response assessment in pediatric neuro-oncology (RAPNO) working group

Criteria for new drug approval include demonstration of efficacy. In neuro-oncology, this is determined radiographically utilizing tumor measurements on MRI scans. Limitations of this method have been identified where drug activity is not reflected in decreased tumor size. The RANO (Response Assessment in Neuro-Oncology) working group was established to address limitations in defining endpoints for clinical trials in adult neuro-oncology and to develop standardized response criteria. RAPNO was subsequently established to address unique issues in pediatric neuro-oncology. The aim of this paper is to delineate response criteria issues in pediatric clinical trials as a basis for subsequent recommendations.

Gliomas in children

OPINION STATEMENT

Gliomas are the most common brain tumor in children and represent nearly 50 % of all pediatric central nervous system (CNS) tumors. They are a heterogeneous group of diseases, ranging from highly malignant and frequently fatal to histologically benign and curable by surgery alone. A uniform treatment approach to these tumors is not practical, due to their histological and biological heterogeneity. Low-grade gliomas (LGGs) are best treated with maximally safe surgical resection, generally achievable for hemispheric or cerebellar locations. Patients with deep midline, optic pathway/hypothalamic, and brain stem locations should undergo subtotal resection or biopsy only. If a complete resection is not feasible, subtotal resection followed by adjuvant chemotherapy or radiotherapy is the standard approach; however, observation alone with serial neuroimaging is used in some asymptomatic, surgically inaccessible lesions. Chemotherapy is used first-line in cases of residual or progressive disease, to avoid or delay radiation therapy and its associated side effects. Regimens demonstrating objective responses and increased progression free survival (PFS) include carboplatin and vincristine (CV), thioguanine/procarbazine/CCNU/vincristine (TPCV), or weekly vinblastine. High-grade gliomas (HGGs) are less common in children than in adults, though are similar in their aggressive clinical behavior, resistance to therapy, and dismal outcomes. There is not a single "standard of care" therapy for non-metastatic HGGs, but generally accepted is an aggressive attempt at a complete surgical resection, followed by multimodality therapy with focal radiation and chemotherapy. The use of temozolomide (TMZ) during and following radiotherapy is common, though it appeared not to improve the outcome in a cooperative group clinical trial when compared to an historical control cohort. The angiogenesis inhibitor bevacizumab, used alone or in combination with irinotecan, is also commonly used as maintenance therapy after radiation. Current trials are prospectively comparing TMZ to newer agents (vorinostat, bevacizumab) in a randomized phase II trial. Brainstem gliomas are a unique category of childhood gliomas. Approximately 80 % of childhood brainstem gliomas arise within the pons as diffuse intrinsic pontine gliomas (DIPG). When biopsied, these are usually HGGs and carry a dismal prognosis. Standard therapy is focal radiation (54-58 Gy), preferably on a clinical trial testing concurrent chemotherapy or biologic agent. No standard chemotherapy agent has impacted survival. The remaining 20 % of brainstem gliomas are low-grade, arise in the midbrain, dorsal medulla, or cervicomedullary junction, and are indolent in nature with a much better prognosis. Improvement in the outcome of all childhood gliomas will require increased knowledge of the underlying biology of these tumors, in order to treat with more biologically based and precise therapies.

Pilocytic astrocytoma: a disease with evolving molecular heterogeneity

Pilocytic astrocytoma, the most common pediatric brain tumor, is a clinically and molecularly heterogeneous disease that occurs most often in the cerebellum and hypothalamic and chiasmatic regions. Classically, pilocytic astrocytomas are driven by the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway. Recently described genetic aberrations involving this pathway are critical for tumorigenesis. Tandem duplication of 7q34 encodes BRAF and produces several KIAA1549-BRAF novel oncogenic fusions. Activating point mutations of BRAF, such as BRAF (V600E), also lead to pilocytic astrocytoma. Loss of the NF1 gene allows hyperactivation of the oncogene KRAS. In this review, we discuss the current understanding of the novel molecular aberrations described in pilocytic astrocytomas and their clinical relevance for prognosis and treatment. The prognostic indications of these aberrations are discussed with regard to tumor location, tumor pathology, and patient age. A better understanding of the evolving molecular heterogeneity of pilocytic astrocytomas offers hope for developing molecularly targeted therapeutic armamentariums.

Long-term outcome of centrally located low-grade glioma in children

BACKGROUND

Optimal management of children with centrally located low-grade glioma (LGG) is unclear. Initial interventions in most children are chemotherapy in younger and radiation therapy (RT) in older children. A better understanding of the inherent risk factors along with the effects of interventions on long-term outcome can lead to reassessment of the current approaches to minimize long-term morbidity.

METHODS

To reassess the current treatment strategies of centrally located LGG, we compared the long-term survival and morbidity of different treatment regimens. Medical records of patients primarily treated at Texas Children's Cancer and Hematology Centers between 1987 and 2008 were reviewed.

RESULTS

Forty-seven patients with a median follow-up of 79 months were included in the analysis. The 5-year overall survival and progression-free survival (PFS) for all patients were 96% and 53%, respectively. The 5-year PFS for those treated initially with RT (12 patients; median age, 11 years [range, 3-15 years]) and with chemotherapy (28 patients; median age, 2 years [range 0-8 years]) were 76% and 37%, respectively (log-rank test P = .02). Among children who progressed after chemotherapy, the 5-year PFS after salvage RT was 55%. Patients diagnosed at a younger age (<5 years) were more likely to experience endocrine abnormalities (Fisher exact test; P<.00001).

CONCLUSIONS

Effective and durable tumor control was obtained with RT as initial treatment. In younger patients, chemotherapy can delay the use of RT; however, frequent progression and long-term morbidity are common. More effective and less toxic therapies are required in these patients, the majority of whom are long-term survivors.

Optic pathway gliomas: a review

Optic pathway gliomas account for 3-5% of all pediatric CNS tumors and represent the most common intrinsic optic nerve tumors. These tumors occur preferentially during the first decade of life and are particularly frequent in children with neurofibromatosis type 1. Although optic pathway gliomas are low-grade tumors, their behavior can be aggressive, and their management is often challenging. Their management includes observation, surgery, chemotherapy and radiation. The role of each modality is discussed as well as current and future developments in treatment, in particular targeted therapies that are currently being investigated.

Optic pathway gliomas in adolescence--time to challenge treatment choices?

BACKGROUND

Optimal management of optic pathway/hypothalamic glioma (OPHG) remains an ongoing challenge. Little is known about the natural history, management strategies, and outcomes in adolescents. Carboplatin-based chemotherapy is a useful modality in younger children, delaying radiation to their immature brains. National trials have focused on younger children and excluded adolescents from studies evaluating the role of chemotherapy.

METHODS

This retrospective study describes clinical characteristics, treatment regimens, and outcomes in adolescents (aged ≥ 10 years) with OPHG (diagnosis during 1990-2006). Progression-free survival was compared with that in a cohort of younger children (aged <10 years).

RESULTS

Thirty-three adolescents (19 females, 6 with neurofibromatosis type 1) with OPHG were identified within 2 Canadian pediatric oncology institutions. The majority presented with visual symptoms (82%). More than 55% (18 of 33) involved the posterior tract and/or hypothalamus (modified Dodge classification 3/4). Seventeen were initially observed; 8 remained progression free. Of the 25 of 33 adolescents who required active treatment, 9 (36%) needed second-line therapy. The progression-free survival for any first active treatment at age <10 years (52 of 102) or ≥ 10 years (25 of 33) was similar (46.9 vs 46.8 months; P = .60). In those who received chemotherapy as first-line treatment or after prior nonchemotherapy treatment failure, the progression-free survival trend was superior (62.9 vs 38.9 months) in those aged ≥ 10 years although not statistically significant (P = .16).

CONCLUSIONS

Chemotherapy is a valuable treatment modality for the achievement of disease control even in adolescents; their progression-free survival compares favorably with that in younger children. We propose that chemotherapy be considered as a first-line modality in adolescents, avoiding potential radiation-associated morbidities.

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.