Sustained Survival Benefit in Recurrent Medulloblastoma by a Metronomic Antiangiogenic Regimen: A Nonrandomized Controlled Trial

Importance

Medulloblastoma recurrence in patients who have previously received irradiation has a dismal prognosis and lacks a standard salvage regimen.

Objective

To evaluate the response rate of pediatric patients with medulloblastoma recurrence using an antiangiogenic metronomic combinatorial approach (Medulloblastoma European Multitarget Metronomic Anti-Angiogenic Trial [MEMMAT]).

Design, Setting, and Participants

This phase 2, investigator-initiated, multicenter nonrandomized controlled trial assessed 40 patients with relapsed or refractory medulloblastoma without a ventriculoperitoneal shunt who were younger than 20 years at original diagnosis. Patients were enrolled between April 1, 2014, and March 31, 2021.

Interventions

Treatment consisted of daily oral thalidomide, fenofibrate, celecoxib, and alternating 21-day cycles of low-dose (metronomic) oral etoposide and cyclophosphamide, supplemented by intravenous bevacizumab and intraventricular therapy consisting of alternating etoposide and cytarabine.

Main Outcomes and Measures

The primary end point was response after 6 months of antiangiogenic metronomic therapy. Secondary end points included progression-free survival (PFS), overall survival (OS), and quality of life. Adverse events were monitored to assess safety.

Results

Of the 40 patients (median [range] age at treatment start, 10 [4-17] years; 25 [62.5%] male) prospectively enrolled, 23 (57.5%) achieved disease control after 6 months of treatment, with a response detected in 18 patients (45.0%). Median OS was 25.5 months (range, 10.9-40.0 months), and median PFS was 8.5 months (range, 1.7-15.4 months). Mean (SD) PFS at both 3 and 5 years was 24.6% (7.9%), while mean (SD) OS at 3 and 5 years was 43.6% (8.5%) and 22.6% (8.8%), respectively. No significant differences in PFS or OS were evident based on molecular subgroup analysis or the number of prior recurrences. In patients demonstrating a response, mean (SD) overall 5-year PFS was 49.7% (14.3%), and for patients who remained progression free for the first 12 months of treatment, mean (SD) 5-year PFS was 66.7% (16.1%). Treatment was generally well tolerated. Grade 3 to 4 treatment-related adverse events included myelosuppression, infections, seizures, and headaches. One heavily pretreated patient with a third recurrence died of secondary acute myeloid leukemia.

Conclusions and Relevance

This feasible and well-tolerated MEMMAT combination regimen demonstrated promising activity in patients with previously irradiated recurrent medulloblastoma. Given these results, this predominantly oral, well-tolerated, and outpatient treatment warrants further evaluation.

Trial Registration

ClinicalTrials.gov Identifier: NCT01356290.

IMG-03. Impact of childhood cerebellar tumor surgery on cognition: Can fMRI serve as a surrogate marker?

BACKGROUND: Childhood cerebellar pilocytic astrocytomas harbour excellent overall survival rates after surgical resection, but the patients may exhibit specific cognitive and behavioural problems emphasising our current understanding of the cerebellar role in cognition. Functional MRI has catalysed the mechanistic insights into brain functional systems and has already been linked with the neuropsychological performance. We aimed to exploit the question whether functional MRI can be used as a surrogate measure for the cognitive outcome assessment of these patients. METHODS: We investigated 13 patients (median age 22.0 years, range 15.2 – 31.7) after a median interval between surgery and examination of 15.0 years (range 4.2 – 20.8) and 16 matched controls. All subjects underwent a functional 3T MRI scans in a resting state condition and a battery neuropsychological tests. RESULTS: Patients showed a significantly increased functional connectivity in the precuneus compared to controls (p<0.05) and at the same time impairments in various domains of neuropsychological functioning such as a lower mean WIE IQ percentile (M = 48.62, SD = 29.14), lower scores in the TMT letter sequencing (M = 49.54, SD = 30.66), worse performance on the WIE subtest Digit Symbol Coding (M = 38.92, SD = 35.29), subtest Symbol Search (M = 40.75, SD = 35,28), and TAP divided attention task (M = 783.92, SD = 73.20). CONCLUSION: Functional MRI has the potential to serve as a surrogate measure for the cognitive outcome assessment. The precuneus brain region is heavily involved in the cerebral associative oversight of cerebellar cognitive function.

Impact of childhood cerebellar tumor surgery on cognition revealed by precuneus hyperconnectivity

Background

Childhood cerebellar pilocytic astrocytomas harbor excellent overall survival rates after surgical resection, but the patients may exhibit specific cognitive and behavioral problems. Functional MRI has catalyzed insights into brain functional systems and has already been linked with the neuropsychological performance. We aimed to exploit the question of whether resting-state functional MRI can be used as a biomarker for the cognitive outcome assessment of these patients.

Methods

We investigated 13 patients (median age 22.0 years; range 14.9-31.3) after a median interval between surgery and examination of 15.0 years (range 4.2-20.5) and 16 matched controls. All subjects underwent functional 3-Tesla MRI scans in a resting-state condition and battery neuropsychological tests.

Results

Patients showed a significantly increased functional connectivity in the precuneus compared with controls (P < .05) and at the same time impairments in various domains of neuropsychological functioning such as a lower mean Wechsler Intelligenztest für Erwachsene (WIE) IQ percentile (mean [M] = 48.62, SD = 29.14), lower scores in the Trail Making Test (TMT) letter sequencing (M = 49.54, SD = 30.66), worse performance on the WIE subtest Digit Symbol Coding (M = 38.92, SD = 35.29), subtest Symbol Search (M = 40.75, SD = 35.28), and test battery for attentional performance (TAP) divided attention task (M = 783.92, SD = 73.20).

Conclusion

Childhood cerebellar tumor treated by resection only strongly impacts the development of precuneus/posterior cingulate cortex functional connectivity. Functional MRI has the potential to help deciphering the pathophysiology of cerebellar-related cognitive impairments in these patients and could be an additional tool in their individual assessment and follow-up.

Predisposition of Wingless Subgroup Medulloblastoma for Primary Tumor Hemorrhage

BACKGROUND

Primary intratumoral hemorrhage as a presenting sign is rare in children with medulloblastomas but may result in severe complications. Given the distinct properties of molecular medulloblastoma subgroups, the impact on neurosurgical practice has still to be defined.

OBJECTIVE

To investigate both clinical and radiological presentation of intratumoral hemorrhage in medulloblastoma patients in the context of molecular subgroups.

METHODS

Data of all consecutive medulloblastoma patients treated at our institution between 1993 and 2018 (n = 104) were retrospectively reviewed in respect of clinical and radiological presentation as well as molecular subgroups. For cases with available tumor tissue (n = 86), subgroups were assigned by either 450 K methylation array or immunohistochemistry and CTNNB1 sequencing. Available imaging at diagnosis (n = 62) was reviewed by an experienced neuroradiologist.

RESULTS

Within the entire cohort, 4 patients (4%) presented with massive spontaneous hemorrhage. Although no patient died as a direct consequence of hemorrhage, all suffered from serious sequelae. Moreover, 3 additional patients displayed radiological evidence of significant hemorrhage. Interestingly, all 7 cases belonged to the wingless (WNT) subgroup (n = 13), resulting in intratumoral hemorrhage in 54% (7/13) of pediatric WNT medulloblastomas. In contrast, significant hemorrhage was absent in all other molecular subgroups.

CONCLUSION

Our results suggest that a substantial proportion of pediatric WNT medulloblastomas display significant intratumoral hemorrhage at the time of diagnosis. Consequently, the presence of significant hemorrhage in fourth ventricle childhood tumors is suggestive of WNT medulloblastoma and should lead to a less aggressive attempt for total resection in this prognostically favorable tumor type.

Personalized Treatment of H3K27M-Mutant Pediatric Diffuse Gliomas Provides Improved Therapeutic Opportunities

Diffuse gliomas with K27M histone mutations (H3K27M glioma) are generally characterized by a fatal prognosis, particularly affecting the pediatric population. Based on the molecular heterogeneity observed in this tumor type, personalized treatment is considered to substantially improve therapeutic options. Therefore, clinical evidence for therapy, guided by comprehensive molecular profiling, is urgently required. In this study, we analyzed feasibility and clinical outcomes in a cohort of 12 H3K27M glioma cases treated at two centers. Patients were subjected to personalized treatment either at primary diagnosis or disease progression and received backbone therapy including focal irradiation. Molecular analyses included whole-exome sequencing of tumor and germline DNA, RNA-sequencing, and transcriptomic profiling. Patients were monitored with regular clinical as well as radiological follow-up. In one case, liquid biopsy of cerebrospinal fluid (CSF) was used. Analyses could be completed in 83% (10/12) and subsequent personalized treatment for one or more additional pharmacological therapies could be recommended in 90% (9/10). Personalized treatment included inhibition of the PI3K/AKT/mTOR pathway (3/9), MAPK signaling (2/9), immunotherapy (2/9), receptor tyrosine kinase inhibition (2/9), and retinoic receptor agonist (1/9). The overall response rate within the cohort was 78% (7/9) including one complete remission, three partial responses, and three stable diseases. Sustained responses lasting for 28 to 150 weeks were observed for cases with PIK3CA mutations treated with either miltefosine or everolimus and additional treatment with trametinib/dabrafenib in a case with BRAFV600E mutation. Immune checkpoint inhibitor treatment of a case with increased tumor mutational burden (TMB) resulted in complete remission lasting 40 weeks. Median time to progression was 29 weeks. Median overall survival (OS) in the personalized treatment cohort was 16.5 months. Last, we compared OS to a control cohort (n = 9) showing a median OS of 17.5 months. No significant difference between the cohorts could be detected, but long-term survivors (>2 years) were only present in the personalized treatment cohort. Taken together, we present the first evidence of clinical efficacy and an improved patient outcome through a personalized approach at least in selected cases of H3K27M glioma.

Cerebellar pilocytic astrocytoma in childhood: Investigating the long-term impact of surgery on cognitive performance and functional outcome

OBJECTIVE

Previous studies differ regarding the long-term effects of surgically removed pediatric cerebellar pilocytic astrocytomas (CPA). Thus, the aim of this study was to investigate the long-term impact on neurocognitive and functional outcome and to analyze age as an influencing factor.

METHODS

Fourteen CPA patients were compared to the age norm and to a group of 14 high-achieving peers regarding cognitive functioning, health-related quality of life (HRQoL), and stress regulation. Mean follow-up time after diagnosis was 13.29 years (range: 3-21 years).

RESULTS

Patients showed satisfactory academic achievement and did not differ from the norm except for the bodily dimension of HRQoL. However, there were marked differences in specific neurocognitive functions between patients and high achievers. Age at diagnosis did not influence neurocognitive outcome.

CONCLUSION

CPA patients treated with surgery only seem to have a favorable long-term outcome, yet, in comparison with high achievers specific cognitive impairments become apparent.

Does the interval from tumour surgery to radiotherapy influence survival in paediatric high grade glioma?

PURPOSE

Paediatric high grade glioma (pHGG) are rare. Following maximum safe resection, children >3 years with HGG receive radiotherapy as standard of care. Whether the interval from tumour surgery to radiotherapy (ISRT) influences survival is disputed in adults with glioblastoma, data for children are lacking. This retrospective single-centre analysis investigates a possible impact of ISRT on survival in paediatric patients with HGG.

METHODS

Survival was analysed in patients aged 3-19 years with non-pontine HGG.

RESULTS

Thirty-eight patients were included (female:male 19:19) with a median age of 11.0 years (3.4-17.7). Seventeen patients had grade 3 and 21 grade 4 glioma. Gross total resection was achieved in 26.3%, partial resection in 36.8% and 36.8% underwent biopsy only. All patients received concomitant and adjuvant chemotherapy. Fifty percent (n = 19) started irradiation ≤17 days (median interval 12 days [range 5-17]), 50% thereafter (median 28 days [range 19-78]). More patients with grade 4 tumours were irradiated shortly after surgery. ISRT (as a continuous variable and dichotomised into two groups by the median ISRT of 18 days) did not significantly influence overall survival (OS) or progression-free survival (PFS). Higher extent of resection (EOR), lower tumour grade as well as chemotherapy with temozolomide had a significant positive impact on OS and PFS in univariate analysis and (except for the effect of temozolomide on PFS) also in multivariable analysis.

CONCLUSIONS

ISRT did not influence survival in pHGG. In view of upcoming targeted treatment options in pHGG the present data suggest that it is safe to perform molecular analyses within a 4-week timeframe before radiotherapy.

From Symptom to Diagnosis-The Prediagnostic Symptomatic Interval of Pediatric Central Nervous System Tumors in Austria

BACKGROUND

Children with central nervous system (CNS) tumours may present with a multitude of symptoms, ranging from elevated intracranial pressure to focal neurological deficit. In everyday practice, some signs may be misleading, thereby causing prolonged prediagnostic symptomatic intervals. Prediagnostic symptomatic intervals are longer for pediatric brain tumors than for other childhood malignancies. This study evaluated prediagnostic symptomatic intervals and parental and diagnostic intervals for pediatric patients with CNS tumours in Austria. It also considered socioeconomic factors.

METHODS

Patients ≤ 19 years of age treated at the Medical University of Vienna and diagnosed during the years 2008 to 2013 were included. Patients diagnosed incidentally or by screening were excluded.

RESULTS

Two hundred twelve consecutive patients were included in the study. They reflected the expected spectrum of CNS tumors. Patients presented with a median of five symptoms at diagnosis, most frequently with signs of elevated intracranial pressure. The median prediagnostic symptomatic interval was 60 days (0 days to seven years), the median parental interval was 30 days (0 days to 6.7 years), and the median diagnostic interval was three days (0 days to 6.5 years). In spinal tumors alone (n = 7), the median prediagnostic symptomatic interval was 70 days (ten days to seven years), and three of seven patients had a prediagnostic symptomatic interval longer than 320 days. Young age, higher tumor grade, and ataxia were associated with a shorter prediagnostic symptomatic interval. Localization in the supratentorial midline, histology of craniopharyngioma, and endocrine symptoms prolonged the prediagnostic symptomatic interval. There was a clear trend for longer prediagnostic symptomatic interval in non-native speakers.

CONCLUSIONS

Results are comparable to other industrialized countries. However, long delays in diagnosis of central nervous system tumors still occur, urging increased awareness.

Neuronal correlates of cognitive function in patients with childhood cerebellar tumor lesions

While it has been shown that cerebellar tumor lesions have an impact on cognitive functions, the extent to which they shape distant neuronal pathways is still largely undescribed. Thus, the present neuroimaging study was designed to investigate different aspects of cognitive function and their neuronal correlates in patients after childhood cerebellar tumor surgery. An alertness task, a working memory task and an incompatibility task were performed by 11 patients after childhood cerebellar tumor surgery and 17 healthy controls. Neuronal correlates as reflected by alterations in functional networks during tasks were assessed using group independent component analysis. We were able to identify eight networks involved during task performance: default mode network, precuneus, anterior salience network, executive control network, visual network, auditory and sensorimotor network and a cerebellar network. For the most ‘basic’ cognitive tasks, a weaker task-modulation of default mode network, left executive control network and the cerebellar network was observed in patients compared to controls. Results for higher-order tasks are in line with a partial restoration of networks responsible for higher-order task execution. Our results provide tentative evidence that the synchronicity of brain activity in patients was at least partially restored in the course of neuroplastic reorganization, particularly for networks related to higher-order cognitive processes. The complex activation patterns underline the importance of testing several cognitive functions to assess the specificity of cognitive deficits and neuronal reorganization processes after brain lesions.

Region Specific Differences of Claudin-5 Expression in Pediatric Intracranial Ependymomas: Potential Prognostic Role in Supratentorial Cases

Ependymomas are common pediatric brain tumors that originate from the ependyma and characterized by poor prognosis due to frequent recurrence. However, the current WHO grading system fails to accurately predict outcome. In a retrospective study, we analyzed 54 intracranial pediatric ependymomas and found a significantly higher overall survival in supratentorial cases when compared to infratentorial tumors. Next we performed region-specific immunohistochemical analysis of the ependyma in neonatal and adult ependyma from the central canal of spinal cord to the choroid plexus of lateral ventricles for components of cell-cell junctions including cadherins, claudins and occludin. We found robust claudin-5 expression in the choroid plexus epithelia but not in other compartments of the ependyma. Ultrastructural studies demonstrated distinct regional differences in cell-cell junction organization. Surprisingly, we found that 9 out of 20 supratentorial but not infratentorial ependymomas expressed high levels of the brain endothelial tight junction component claudin-5 in tumor cells. Importantly, we observed an increased overall survival in claudin-5 expressing supratentorial ependymoma. Our data indicates that claudin-5 expressing ependymomas may follow a distinct course of disease. The assessment of claudin-5 expression in ependymoma has the potential to become a useful prognostic marker in this pediatric malignancy.

Chromosome 1q gain and tenascin-C expression are candidate markers to define different risk groups in pediatric posterior fossa ependymoma

Intracranial classic (WHO grade II) and anaplastic (WHO grade III) ependymomas are among the most common tumors in pediatric patients and have due to frequent recurrences and late relapses a relatively poor outcome. The impact of histopathological grading on patient outcome is controversial and therefore, molecular prognostic and predictive markers are needed to improve patient outcome. To date, the most promising candidate marker is chromosome 1q gain, which has been associated in independent studies with adverse outcome. Furthermore, gene expression and methylation profiles revealed distinct molecular subgroups in the supratentorial and posterior fossa (PF) compartment and Laminin alpha-2 (LAMA2) and Neural Epidermal Growth Factor Like-2 (NELL2) were suggested as surrogate markers for the two PF subgroups PF-EPN-A and PF-EPN-B. PF-EPN-A tumors were also characterized by tenascin-C (TNC) expression and tenascin-C has been suggested as candidate gene on 9q, involved in tumor progression. Therefore, we have analyzed the status of chromosome 1q, TNC, LAMA2, and NELL2 expression in a series of pediatric PF ependymomas in terms of their frequency, associations among themselves, and clinical parameters, as well as their prognostic impact. We confirm the negative prognostic impact of 1q gain and TNC expression and could classify PF ependymomas by these two markers into three molecular subgroups. Tumors with combined 1q gain and TNC expression had the poorest, tumors without 1q gain and TNC expression had a favorable and TNC positive 1q non-gained cases had an intermediate outcome. We found also differences in age and tumor grade in the three subgroups and thus, provide evidence that PF pediatric ependymomas can be divided by chromosome 1q status and TNC expression in three molecular subgroups with distinct clinico-pathological features. These analyses require only few amounts of tumor tissue, are broadly available in the routine clinical neuropathological setting and thus, could be used in further therapy trials to optimize treatment of ependymoma patients.

Atypical teratoid rhabdoid tumor: improved long-term survival with an intensive multimodal therapy and delayed radiotherapy. The Medical University of Vienna Experience 1992-2012

Atypical teratoid rhabdoid tumors (ATRTs) are recently defined highly aggressive embryonal central nervous system tumors with a poor prognosis and no definitive guidelines for treatment. We report on the importance of an initial correct diagnosis and disease-specific therapy on outcome in 22 consecutive patients and propose a new treatment strategy. From 1992 to 2012, nine patients initially diagnosed correctly as ATRT (cohort A, median age 24 months) were treated according to an intensive multimodal regimen (MUV-ATRT) consisting of three 9-week courses of a dose-dense regimen including doxorubicin, cyclophosphamide, vincristine, ifosfamide, cisplatin, etoposide, and methotrexate augmented with intrathecal therapy, followed by high-dose chemotherapy (HDCT) and completed with local radiotherapy. Thirteen patients were treated differently (cohort B, median age 30 months) most of whom according to protocols in use for their respective diagnoses. As of July 2013, 5-year overall survival (OS) and event-free survival (EFS) for all 22 consecutive patients was 56.3 ± 11.3% and 52.9 ± 11.0%, respectively. For MUV-ATRT regimen-treated patients (cohort A) 5-year OS was 100% and EFS was 88.9 ± 10.5%. For patients treated differently (cohort B) 5-year OS and EFS were 28.8 ± 13.1%. All nine MUV-ATRT regimen-treated patients are alive for a median of 76 months (range: 16–197), eight in first complete remission. Our results compare favorably to previously published data. The drug combination and sequence used in the proposed MUV-ATRT regimen appear to be efficacious in preventing early relapses also in young children with M1–M3 stage disease allowing postponement of radiotherapy until after HDCT.

Antiangiogenic metronomic therapy for children with recurrent embryonal brain tumors

BACKGROUND

Median survival time of recurrent embryonal brain tumors is short regardless of salvage chemotherapy used. An evolving alternative approach to conventional chemotherapy is to target neovascularization by interfering with tumor angiogenesis at various levels.

PROCEDURE

From November 2006 to December 2010, 16 patients (median age: 9 years) with recurrent (9 first, 7 multiple) embryonal brain tumors were treated with an antiangiogenic multidrug combination regimen (bevacizumab, thalidomide, celecoxib, fenofibrate, etoposide, and cyclophophamide) and additional intraventricular therapy (etoposide and liposomal cytarabine).

RESULTS

At a median of 33 months, 10/16 patients are alive. 4/4 patients with CNS primitive neuroectodermal tumors (CNS PNET) and 1/7 patients with medulloblastoma (MB) died of tumor progression during the first year. Another patient with MB died of an accident after 23 months, the remaining five patients with MB are alive for 12, 33, 33, 37, and 58 months. For the seven patients with MB, both overall survival (OS) and event free survival (EFS) after 6 months was 100%, after 12 months 85.7 ± 13%, and after 24 months 68.6 ± 19%. In contrast, for patients with CNS PNET, both OS and EFS after 6 months was 75.0 ± 22% and 0.0% and all patients had died by 12 months. Low-dose oral etoposide and cyclophosphamide was reduced after a median of 2 months and discontinued after a median of 11 months. Toxicities were manageable and therapy was generally well tolerated.

CONCLUSION

Our results suggest that the chosen antiangiogenic drug combination is particularly beneficial for patients with MB and warrants further investigation.