Dissecting the functional significance of HSP90AB1 and other heat shock proteins in countering glioblastomas and ependymomas using omics analysis and drug prediction using virtual screening

Heat shock proteins (HSPs) are the evolutionary family of proteins that are highly conserved and present widely in various organisms and play an array of important roles and cellular functions. Currently, very few or no studies are based on the systematic analysis of the HSPs in Glioblastoma (GBMs) and ependymomas. We performed an integrated omics analysis to predict the mutual regulatory differential HSP signatures that were associated with both glioblastoma and ependymomas. Further, we explored the various common dysregulated biological processes operating in both the tumors, and were analyzed using functional enrichment, gene ontology along with the pathway analysis of the predicted HSPs. We established an interactome network of protein-protein interaction (PPIN) to identify the hub HSPs that were commonly associated with GBMs and ependymoma. To understand the mutual molecular mechanism of the HSPs in both malignancies, transcription factors, and miRNAs overlapping with both diseases were explored. Moreover, a transcription factor-miRNAs-HSPs coregulatory network was constructed along with the prediction of potential candidate drugs that were based on perturbation-induced gene expression analysis. Based on the RNA-sequencing data, HSP90AB1 was identified as the most promising target among other predicted HSPs. Finally, the ranking of the drugs was arranged based on various drug scores. In conclusion, this study gave a spotlight on the mutual targetable HSPs, biological pathways, and regulatory signatures associated with GBMs and ependymoma with an improved understanding of crosstalk involved. Additionally, the role of therapeutics was also explored against HSP90AB1. These findings could potentially be able to explain the interplay of HSP90AB1 and other HSPs within these two malignancies.

A phase II study of dose-dense temozolomide and lapatinib for recurrent low-grade and anaplastic supratentorial, infratentorial, and spinal cord ependymoma

BACKGROUND

No standard medical treatment exists for adult patients with recurrent ependymoma, and prospective clinical trials in this population have not succeeded because of its rarity and challenges in accruing patients. The Collaborative Ependymoma Research Network conducted a prospective phase II clinical trial of dose-dense temozolomide (TMZ) and lapatinib, targeting the unmethylated O6-methylguanine-DNA methyltransferase (MGMT) promoter status and increased expression of ErbB2 (human epidermal growth factor receptor 2) and ErbB1 (epidermal growth factor receptor) in ependymomas.

METHODS

Patients age 18 or older with histologically proven and progressive ependymoma or anaplastic ependymoma were eligible and received dose-dense TMZ and daily lapatinib. The primary outcome measure was median progression-free survival (PFS). Landmark 6- and 12-month PFS and objective response were measured. Serial assessments of symptom burden using the MD Anderson Symptom Inventory Brain Tumor (MDASI-BT)/MDASI-Spine Tumor modules were collected.

RESULTS

The 50 patients enrolled had a median age of 43.5 years, median Karnofsky performance status of 90, and a median of 2 prior relapses. Twenty patients had grade III, 16 grade II, and 8 grade I ependymoma. Half had spinal cord tumors; 15 had a supratentorial tumor, 8 infratentorial, and 2 had disseminated disease. Treatment was well tolerated. The median PFS was 7.8 months (95% CI: 5.5,12.2); the 6- and 12-month PFS rates were 55% and 38%, with 2 complete and 6 partial responses. Measures of symptom burden showed reduction in moderate-severe pain and other disease-related symptoms in most patients.

CONCLUSIONS

This treatment, with demonstrated clinical activity with objective responses and prolonged disease control associated with disease-related symptom improvements, is an option as a salvage regimen for adult patients with recurrent ependymoma.

The BET Inhibitor OTX015 Exhibits In Vitro and In Vivo Antitumor Activity in Pediatric Ependymoma Stem Cell Models

Childhood ependymomas are heterogenous chemoresistant neoplasms arising from aberrant stem-like cells. Epigenome deregulation plays a pivotal role in ependymoma pathogenesis, suggesting that epigenetic modifiers hold therapeutic promise against this disease. Bromodomain and extraterminal domain (BET) proteins are epigenome readers of acetylated signals in histones and coactivators for oncogenic and stemness-related transcriptional networks, including MYC/MYCN (Proto-Oncogene, BHLH Transcritpion Factor)-regulated genes. We explored BET inhibition as an anticancer strategy in a panel of pediatric patient-derived ependymoma stem cell models by OTX015-mediated suppression of BET/acetylated histone binding. We found that ependymoma tissues and lines express BET proteins and their targets MYC and MYCN. In vitro, OTX015 reduced cell proliferation by inducing G0/G1-phase accumulation and apoptosis at clinically tolerable doses. Mechanistically, inhibitory p21 and p27 increased in a p53-independent manner, whereas the proliferative driver, phospho-signal transducer and activator of transcription 3 (STAT3), decreased. Upregulation of apoptosis-related proteins and survivin downregulation were correlated with cell line drug sensitivity. Minor alterations of MYC/MYCN expression were reported. In vivo, OTX015 significantly improved survival in 2/3 orthotopic ependymoma models. BET proteins represent promising targets for pharmaceutical intervention with OTX015 against ependymoma. The identification of predictive determinants of sensitivity may help identify ependymoma molecular subsets more likely to benefit from BET inhibitor therapies.

Bevacizumab as a surgery-sparing agent for spinal ependymoma in patients with neurofibromatosis type II: Systematic review and case

Neurofibromatosis type 2 (NF2) is a rare, hereditary tumor syndrome, often requiring repeated surgeries for multiple lesions with significant cumulative morbidity. As such, non-operative management should be considered when possible for this patient population. The aim of this study is to provide a systematic review of the literature regarding this treatment strategy. A descriptive case of a patient in whom bevacizumab treatments enabled over 15 years of surgical postponement for a symptomatic spinal cord ependymoma is also provided. Evidence suggests that bevacizumab is a reasonable surgery-deferring option for cystic lesions, and it may be especially useful in NF2 patients to reduce cumulative morbidity.

Sub-group, Sub-type, and Cell-type Heterogeneity of Ependymoma

Ependymomas are aggressive central nervous system tumors that resist chemotherapy. In this issue of Cancer Cell, Gojo et al. dissect the single cell transcriptional landscapes of ependymoma to define cellular programs that mediate therapeutic resistance, tumor aggressiveness, and potential targets for therapy.

Infusion of 5-Azacytidine (5-AZA) into the fourth ventricle or resection cavity in children with recurrent posterior Fossa Ependymoma: a pilot clinical trial

BACKGROUND

DNA methylation inhibitors are logical therapeutic candidates for ependymomas originating in the posterior fossa of the brain. Our objective was to test the safety of infusing 5-Azacytidine (5-AZA), a DNA methylation inhibitor, directly into cerebrospinal fluid (CSF) spaces of the fourth ventricle or tumor resection cavity in children with recurrent ependymoma originating in the posterior fossa.

MATERIALS AND METHODS

In patients with recurrent ependymoma whose disease originated in the posterior fossa, a maximal safe subtotal tumor resection was performed. At the conclusion of the tumor resection, a catheter was surgically placed into the fourth ventricle or tumor resection cavity and attached to a ventricular access device. CSF flow from the posterior fossa to the sacrum was confirmed by CINE phase contrast magnetic resonance imaging (MRI) postoperatively. 12 consecutive weekly 10 milligram (mg) infusions of 5-Azacytidine (AZA) were planned. Disease response was monitored with MRI scans and CSF cytology.

RESULTS

Six patients were enrolled. One patient was withdrawn prior to planned 5-AZA infusions due to surgical complications after tumor resection. The remaining five patients received 8, 12, 12, 12, and 12 infusions, respectively. There were no serious adverse events or new neurological deficits attributed to 5-AZA infusions. All five patients with ependymoma who received 5-AZA infusions had progressive disease. Two of the five patients, however, were noted to have decrease in the size of at least one intraventricular lesion.

CONCLUSION

5-AZA can be infused into the fourth ventricle or posterior fossa tumor resection cavity without causing neurological toxicity. Future studies with higher doses and/or increased dosing frequency are warranted.

A phase I study of single-agent perifosine for recurrent or refractory pediatric CNS and solid tumors

The PI3K/Akt/mTOR signaling pathway is aberrantly activated in various pediatric tumors. We conducted a phase I study of the Akt inhibitor perifosine in patients with recurrent/refractory pediatric CNS and solid tumors. This was a standard 3+3 open-label dose-escalation study to assess pharmacokinetics, describe toxicities, and identify the MTD for single-agent perifosine. Five dose levels were investigated, ranging from 25 to 125 mg/m2/day for 28 days per cycle. Twenty-three patients (median age 10 years, range 4-18 years) with CNS tumors (DIPG [n = 3], high-grade glioma [n = 5], medulloblastoma [n = 2], ependymoma [n = 3]), neuroblastoma (n = 8), Wilms tumor (n = 1), and Ewing sarcoma (n = 1) were treated. Only one DLT occurred (grade 4 hyperuricemia at dose level 4). The most common grade 3 or 4 toxicity at least possibly related to perifosine was neutropenia (8.7%), with the remaining grade 3 or 4 toxicities (fatigue, hyperglycemia, fever, hyperuricemia, and catheter-related infection) occurring in one patient each. Pharmacokinetics was dose-saturable at doses above 50 mg/m2/day with significant inter-patient variability, consistent with findings reported in adult studies. One patient with DIPG (dose level 5) and 4 of 5 patients with high-grade glioma (dose levels 2 and 3) experienced stable disease for two months. Five subjects with neuroblastoma (dose levels 1 through 4) achieved stable disease which was prolonged (≥11 months) in three. No objective responses were noted. In conclusion, the use of perifosine was safe and feasible in patients with recurrent/refractory pediatric CNS and solid tumors. An MTD was not defined by the 5 dose levels investigated. Our RP2D is 50 mg/m2/day.

Phase I study of 5-fluorouracil in children and young adults with recurrent ependymoma

BACKGROUND

We report a phase I study to examine the pharmacokinetics, safety, and recommended dosage of weekly intravenous bolus 5-fluorouracil (5-FU) in children and young adults with recurrent ependymoma.

METHODS

Patients 22 years of age or less with recurrent ependymoma were treated with bolus dosage 5-FU weekly for 4 weeks followed by a 2-week rest period, defining one cycle. Patients could continue on therapy for 16 cycles. The starting 5-FU dosage was 500 mg/m(2). Dose-limiting toxicity was determined after one cycle. Patients were initially enrolled according to a rolling-6 design; subsequent dose re-escalation phase was based on a 3 + 3 design.

RESULTS

We treated patients at 400 (n = 6), 500 (n = 15), and 650 (n = 5) mg/m(2), with de-escalation due to toxicity. Twenty-three of twenty-six patients enrolled were evaluable. Five patients experienced grade 4 neutropenia (n = 2: 650 mg/m(2); n = 3: 500 mg/m(2)). One patient experienced grade 3 diarrhea. At 500 mg/m(2), the median 5-FU maximal concentration, AUC0-∞, and alpha half-life were 825 µM, 205 µM × h, and 9.9 min, respectively. Interim analysis revealed an association between hematologic toxicity and prior number of chemotherapeutic regimens (P = .03). The study was amended to re-escalate the dosage in a less heavily pretreated cohort of patients.

CONCLUSIONS

These phase I clinical data provide initial pharmacokinetic parameters to describe i.v. bolus 5-FU disposition in children with recurrent ependymoma. Tumor exposures effective in preclinical testing can be achieved with tolerable bolus dosages in patients. Bolus 5-FU is well tolerated and possesses antitumor activity.

Growth-factor-driven rescue to receptor tyrosine kinase (RTK) inhibitors through Akt and Erk phosphorylation in pediatric low grade astrocytoma and ependymoma

Up to now, several clinical studies have been started investigating the relevance of receptor tyrosine kinase (RTK) inhibitors upon progression free survival in various pediatric brain tumors. However, single targeted kinase inhibition failed, possibly due to tumor resistance mechanisms. The present study will extend our previous observations that vascular endothelial growth factor receptor (VEGFR)-2, platelet derived growth factor receptor (PDGFR)β, Src, the epidermal growth factor receptor (ErbB) family, and hepatocyte growth factor receptor (HGFR/cMet) are potentially drugable targets in pediatric low grade astrocytoma and ependymoma with investigations concerning growth-factor-driven rescue. This was investigated in pediatric low grade astrocytoma and ependymoma cell lines treated with receptor tyrosine kinase (RTK) inhibitors e.g. sorafenib, dasatinib, canertinib and crizotinib. Flow cytometry analyses showed high percentage of cells expressing VEGFR-1, fibroblast growth factor receptor (FGFR)-1, ErbB1/EGFR, HGFR and recepteur d’origine nantais (RON) (respectively 52-77%, 34-51%, 63-90%, 83-98%, 65-95%). Their respective inhibitors induced decrease of cell viability, measured with WST-1 cell viability assays. At least this was partially due to increased apoptotic levels measured by Annexin V/Propidium Iodide apoptosis assays. EGF, HGF and FGF, which are normally expressed in brain (tumor) tissue, showed to be effective rescue inducing growth factors resulting in increased cell survival especially during treatment with dasatinib (complete rescue) or sorafenib (partial rescue). Growth-factor-driven rescue was less prominent when canertinib or crizotinib were used. Rescue was underscored by significantly activating downstream Akt and/or Erk phosphorylation and increased tumor cell migration. Combination treatment showed to be able to overcome the growth-factor-driven rescue. In conclusion, our study highlights the extensive importance of environmentally present growth factors in developing tumor escape towards RTK inhibitors in pediatric low grade astrocytoma and ependymoma. It is of great interest to anticipate upon these results for the design of new therapeutic trials with RTK inhibitors in these pediatric brain tumors.

Preclinical examination of clofarabine in pediatric ependymoma: intratumoral concentrations insufficient to warrant further study

Clofarabine, a deoxyadenosine analog, was an active anticancer drug in our in vitro high-throughput screening against mouse ependymoma neurospheres. To characterize the clofarabine disposition in mice for further preclinical efficacy studies, we evaluated the plasma and central nervous system disposition in a mouse model of ependymoma. A plasma pharmacokinetic study of clofarabine (45 mg/kg, IP) was performed in CD1 nude mice bearing ependymoma to obtain initial plasma pharmacokinetic parameters. These estimates were used to derive D-optimal plasma sampling time points for cerebral microdialysis studies. A simulation of clofarabine pharmacokinetics in mice and pediatric patients suggested that a dosage of 30 mg/kg IP in mice would give exposures comparable to that in children at a dosage of 148 mg/m(2). Cerebral microdialysis was performed to study the tumor extracellular fluid (ECF) disposition of clofarabine (30 mg/kg, IP) in the ependymoma cortical allografts. Plasma and tumor ECF concentration-time data were analyzed using a nonlinear mixed effects modeling approach. The median unbound fraction of clofarabine in mouse plasma was 0.79. The unbound tumor to plasma partition coefficient (K pt,uu: ratio of tumor to plasma AUCu,0-inf) of clofarabine was 0.12 ± 0.05. The model-predicted mean tumor ECF clofarabine concentrations were below the in vitro 1-h IC50 (407 ng/mL) for ependymoma neurospheres. Thus, our results show the clofarabine exposure reached in the tumor ECF was below that associated with an antitumor effect in our in vitro washout study. Therefore, clofarabine was de-prioritized as an agent to treat ependymoma, and further preclinical studies were not pursued.

Telomerase inhibition abolishes the tumorigenicity of pediatric ependymoma tumor-initiating cells

Pediatric ependymomas are highly recurrent tumors resistant to conventional chemotherapy. Telomerase, a ribonucleoprotein critical in permitting limitless replication, has been found to be critically important for the maintenance of tumor-initiating cells (TICs). These TICs are chemoresistant, repopulate the tumor from which they are identified, and are drivers of recurrence in numerous cancers. In this study, telomerase enzymatic activity was directly measured and inhibited to assess the therapeutic potential of targeting telomerase. Telomerase repeat amplification protocol (TRAP) (n = 36) and C-circle assay/telomere FISH/ATRX staining (n = 76) were performed on primary ependymomas to determine the prevalence and prognostic potential of telomerase activity or alternative lengthening of telomeres (ALT) as telomere maintenance mechanisms, respectively. Imetelstat, a phase 2 telomerase inhibitor, was used to elucidate the effect of telomerase inhibition on proliferation and tumorigenicity in established cell lines (BXD-1425EPN, R254), a primary TIC line (E520) and xenograft models of pediatric ependymoma. Over 60 % of pediatric ependymomas were found to rely on telomerase activity to maintain telomeres, while no ependymomas showed evidence of ALT. Children with telomerase-active tumors had reduced 5-year progression-free survival (29 ± 11 vs 64 ± 18 %; p = 0.03) and overall survival (58 ± 12 vs 83 ± 15 %; p = 0.05) rates compared to those with tumors lacking telomerase activity. Imetelstat inhibited proliferation and self-renewal by shortening telomeres and inducing senescence in vitro. In vivo, Imetelstat significantly reduced subcutaneous xenograft growth by 40 % (p = 0.03) and completely abolished the tumorigenicity of pediatric ependymoma TICs in an orthotopic xenograft model. Telomerase inhibition represents a promising therapeutic approach for telomerase-active pediatric ependymomas found to characterize high-risk ependymomas.

Chemo-predictive assay for targeting cancer stem-like cells in patients affected by brain tumors

Administration of ineffective anticancer therapy is associated with unnecessary toxicity and development of resistant clones. Cancer stem-like cells (CSLCs) resist chemotherapy, thereby causing relapse of the disease. Thus, development of a test that identifies the most effective chemotherapy management offers great promise for individualized anticancer treatments. We have developed an ex vivo chemotherapy sensitivity assay (ChemoID), which measures the sensitivity of CSLCs as well as the bulk of tumor cells to a variety of chemotherapy agents. Two patients, a 21-year old male (patient 1) and a 5-month female (patient 2), affected by anaplastic WHO grade-III ependymoma were screened using the ChemoID assay. Patient 1 was found sensitive to the combination of irinotecan and bevacizumab, which resulted in a prolonged disease progression free period of 18 months. Following recurrence, the combination of various chemotherapy drugs was tested again with the ChemoID assay. We found that benzyl isothiocyanate (BITC) greatly increased the chemosensitivity of the ependymoma cells to the combination of irinotecan and bevacizumab. After patient 1 was treated for two months with irinotecan, bevacizumab and supplements of cruciferous vegetable extracts containing BITC, we observed over 50% tumoral regression in comparison with pre-ChemoID scan as evidenced by MRI. Patient 2 was found resistant to all treatments tested and following 6 cycles of vincristine, carboplatin, cyclophosphamide, etoposide, and cisplatin in various combinations, the tumor of this patient rapidly progressed and proton beam therapy was recommended. As expected animal studies conducted with patient derived xenografts treated with ChemoID screened drugs recapitulated the clinical observation. This assay demonstrates that patients with the same histological stage and grade of cancer may vary considerably in their clinical response, suggesting that ChemoID testing which measures the sensitivity of CSLCs as well as the bulk of tumor cells to a variety of chemotherapy agents could lead to more effective and personalized anticancer treatments in the future.

Nf2/Merlin controls spinal cord neural progenitor function in a Rac1/ErbB2-dependent manner

Objective

Individuals with the neurofibromatosis type 2 (NF2) cancer predisposition syndrome develop spinal cord glial tumors (ependymomas) that likely originate from neural progenitor cells. Whereas many spinal ependymomas exhibit indolent behavior, the only treatment option for clinically symptomatic tumors is surgery. In this regard, medical therapies are unfortunately lacking due to an incomplete understanding of the critical growth control pathways that govern the function of spinal cord (SC) neural progenitor cells (NPCs).

Methods

To identify potential therapeutic targets for these tumors, we leveraged primary mouse Nf2-deficient spinal cord neural progenitor cells.

Results

We demonstrate that the Nf2 protein, merlin, negatively regulates spinal neural progenitor cell survival and glial differentiation in an ErbB2-dependent manner, and that NF2-associated spinal ependymomas exhibit increased ErbB2 activation. Moreover, we show that Nf2-deficient SC NPC ErbB2 activation results from Rac1-mediated ErbB2 retention at the plasma membrane.

Significance

Collectively, these findings establish ErbB2 as a potential rational therapeutic target for NF2-associated spinal ependymoma.

[Antiangiogenic treatment of pediatric CNS tumors in Hungary with the Kieran schedule]

In Hungary a new oral antiangiogenic treatment was introduced in cases of primary chemoresistant or recurrent pediatric CNS tumors, called Kieran schedule. The early results of this treatment were analyzed. From 2010 at Semmelweis University on individual decisions a daily combined per oral treatment was introduced in pediatric patients with recurrent or progressive CNS tumor (Kieran schedule: thalidomid, celecoxib, etoposid and cyclophosphamid). Efficacy of therapy was analyzed in terms of demographic data, histology, side effects and tolerability in a retrospective manner. From 2010 through 2013, twenty patients were treated with Kieran schedule (medulloblastoma: 3, ependymoma: 5, anaplastic astrocytoma: 2, GBM: 4, plexus choroideus carcinoma: 1, central primitive neuroectodermal tumor: 1, optic glioma: 2, brainstem tumor: 2). Median treatment time and median progression-free survival were 0.60 and 0.61 years, respectively. Based on the preliminary analysis of a limited cohort of patients, the therapy was efficient in those cases of medulloblastoma, ependymoma, high-grade and optic gliomas, where the expected survival time was more than 3 months at start of treatment. Side effects were slight myelosuppresion in terms of previous therapy, 16% transient ischemic attack (TIA)-like episodes. During therapy patients could live their everyday life. Kieran schedule was well-tolerable and efficient with good quality of life in certain cases of pediatric CNS tumors.

PI3K pathway activation provides a novel therapeutic target for pediatric ependymoma and is an independent marker of progression-free survival

PURPOSE

Currently, there are few effective adjuvant therapies for pediatric ependymoma outside confocal radiation, and prognosis remains poor. The phosphoinositide 3-kinase (PI3K) pathway is one of the most commonly activated pathways in cancer. PI3Ks transduce signals from growth factors and cytokines, resulting in the phosphorylation and activation of AKT, which in turn induces changes in cell growth, proliferation, and apoptosis.

EXPERIMENTAL DESIGN

PI3K pathway status was analyzed in ependymoma using gene expression data and immunohistochemical analysis of phosphorylated AKT (P-AKT). The effect of the PI3K pathway on cell proliferation was investigated by immunohistochemical analysis of cyclin D1 and Ki67, plus in vitro functional analysis. To identify a potential mechanism of PI3K pathway activation, PTEN protein expression and the mutation status of PI3K catalytic subunit α-isoform gene (PIK3CA) was investigated.

RESULTS

Genes in the pathway displayed significantly higher expression in supratentorial than in posterior fossa and spinal ependymomas. P-AKT protein expression, indicating pathway activation, was seen in 72% of tumors (n = 169) and P-AKT expression was found to be an independent marker of a poorer progression-free survival. A significant association between PI3K pathway activation and cell proliferation was identified, suggesting that pathway activation was influencing this process. PTEN protein loss was not associated with P-AKT staining and no mutations were identified in PIK3CA.

CONCLUSIONS

Our results suggest that the PI3K pathway could act as a biomarker, not only identifying patients with a worse prognosis but also those that could be treated with therapies targeted against the pathway, a strategy potentially effective in a high percentage of ependymoma patients.

Metronomic cyclophosphamide with cisplatin and bevacizumab: a new chemotherapeutic regimen for refractory anaplastic ependymoma

Anaplastic ependymoma is a rare brain tumor, induced both in the brain and the spine. The treatment relies on surgery and radiotherapy. Upon failure of these treatments, chemotherapy has modest effects. Here, we report two cases of anaplastic ependymoma with prolonged radiological and clinical responses to a metronomic cyclophosphamide, cisplatin and bevacizumab regimen. Two patients with anaplastic ependymoma, refractory to surgery and radiotherapy were proposed for a chemotherapeutic treatment. These patients had both spina and brain nodules. Neurological symptoms included arm deficiencies and paraparesia.

RESULTS

Six cycles of the metronomic cyclophosphamide (50 mg per day, daily), cisplatin (100 mg/m(2) every four weeks) and bevacizumab (10 mg/kg every two weeks), as a chemotherapeutic regimen, induced both radiological response on magnetic resonance imaging and clinical response with neurological deficiency regression. At one year, the patients were still under maintenance therapy with metronomic cyclophosphamide and cisplatin. This treatment still continues to control tumor progression and symptoms.

CONCLUSION

This is the first report showing an impressive efficacy of metronomic the cyclophosphamide, cisplatin and bevacizumab chemotherapeutic regimen for the treatment of refractory anaplastic ependymoma.

Effects of epidermal growth factor receptor blockade on ependymoma stem cells in vitro and in orthotopic mouse models

Some lines of evidence suggest that tumors, including ependymoma, might arise from a subpopulation of cells, termed cancer stem cells (CSCs), with self-renewal and tumor-initiation properties. Given the strict dependence of CSCs on epidermal growth factor (EGF) through EGF receptor (EGFR), we investigated the effects of EGFR inhibitors in ependymoma-stem cells (SCs) in vitro and in orthotopic mouse models. We established two ependymoma-SC lines from two recurrent pediatric ependymoma. Both lines expressed markers of radial glia--the candidate SCs of ependymoma--and showed renewal ability, multipotency, and tumorigenicity after orthotopic implantation, despite markedly different expression of CD133 (94 vs. 6%). High phosphorylated-EGFR/EGFR ratio was detected, which decreased after differentiation. EGFR inhibitors (gefitinib and AEE788) reduced clonogenicity, proliferation and survival of ependymoma-SC lines dose-dependently, and blocked EGF-induced activation of EGFR, Akt and extracellular signal-regulated kinase 1/2. Overall, AEE788 was more effective than gefitinib. EGFR blockade as well as differentiation strongly reduced CD133 expression. However, ex vivo treatment with AEE788 did not impair orthotopic tumor engraftment, whereas ex vivo differentiation did, suggesting that CD133 does not absolutely segregate for tumorigenicity in ependymoma-SCs. Orally administered AEE788 prolonged survival of mice bearing ependymoma-SC-driven orthotopic xenografts from 56 to 63 days, close to statistical significance (log-rank p=0.06). Our study describes for the first time EGFR signaling in ependymoma-SCs and the effects of EGFR blockade in complementary in vitro and in vivo systems. The experimental models we developed can be used to further investigate the activity of EGFR inhibitors or other antineoplastic agents in this tumor.

An integrated in vitro and in vivo high-throughput screen identifies treatment leads for ependymoma

Using a mouse model of ependymoma-a chemoresistant brain tumor-we combined multicell high-throughput screening (HTS), kinome-wide binding assays, and in vivo efficacy studies, to identify potential treatments with predicted toxicity against neural stem cells (NSC). We identified kinases within the insulin signaling pathway and centrosome cycle as regulators of ependymoma cell proliferation, and their corresponding inhibitors as potential therapies. FDA approved drugs not currently used to treat ependymoma were also identified that posses selective toxicity against ependymoma cells relative to normal NSCs both in vitro and in vivo, e.g., 5-fluorouracil. Our comprehensive approach advances understanding of the biology and treatment of ependymoma including the discovery of several treatment leads for immediate clinical translation.

Response to temozolomide in supratentorial multifocal recurrence of malignant ependymoma

Intracranial anaplastic ependymomas are a very rare entity within the group of adult CNS neoplasms. Thus, no standard adjuvant therapy after surgical resection has been defined so far. External radiotherapy is commonly administered, but the role of chemotherapy is still unclear in malignant ependymomas. The case of a 25-year-old female patient with multifocal recurrence of a supratentorial malignant ependymoma administered temozolomide as second-line therapy is reported. Currently, 5 months after initiation of temozolomide treatment, there is no evidence of radiographic progression. Temozolomide could constitute a promising approach to supratentorial recurrent and multifocal anaplastic ependymoma of adults.

[The safety of combination chemotherapy with ifosfamide, cisplatin, and etoposide (ICE): single-institution retrospective review of 108 cases]

PURPOSE

The adverse effects of combination chemotherapy of ifosfamide, cisplatin, and etoposide (ICE) were evaluated in the treatment of various intracranial brain tumors.

METHODS

108 cases were retrospectively reviewed. The histological diagnosis was newly diagnosed or recurrent germ cell tumor in 45 cases, medulloblastoma in 19, primitive neuroectodermal tumor (PNET) in 7, anaplastic ependymoma in 6, recurrent glioblastoma in 13, and others in 18 cases. Patients received 1-8 cycles of ICE chemotherapy with or without radiation therapy. The adverse effects were analyzed based on the the clinical or laboratory examinations.

RESULTS

Common Terminology Criteria for Adverse Events ver. 3.0 (CTCAE v3.0) grade 4 neutropenia, anemia, and thrombocytopenia occurred in 81.4%, 14.8%, and 35.2% of patients, respectively. Non-hematological adverse effects, including infection, elevated aspartate aminotransferase (AST)/alanine aminotransferase (ALT), high or low levels of serum sodium, and seizure, occurred in 26.8%, 29.6%, 28.7%, and 11.1% of patients, respectively. One patient died of opportunistic infection with neutropenia. The proportion of ICE cycles associated with CTCAE v3.0 grade 4 neutropenia, transfusion of platelets, and elevated AST/ALT significantly decreased after enforcement of dose reduction criteria.

CONCLUSION

The high rate of adverse effects requires close follow up and dose reduction.

Salvage chemotherapy for metastatic and recurrent ependymoma of childhood

INTRODUCTION

Chemotherapy has limited role in the up-front management of ependymoma. At the time of recurrence, the role of chemotherapy is also ill defined and the choice of chemotherapeutic agents is often arbitrary, based on anecdotal data and personal experience.

METHODS

The purpose of this review is to describe and critically analyze the published literature on chemotherapy in patients with recurrent and metastatic ependymoma.

DISCUSSION

The disappointing response rate with single agents (12.9%) and combinations (17.4%) emphasizes the need to re-evaluate the current chemotherapeutic approach of intracranial ependymoma, and biological studies are needed to identify targets that may be considered for clinical trials.

Intracavitary chemotherapy (Gliadel) and oral low-dose etoposide for recurrent anaplastic ependymoma

Anaplastic ependymoma is associated with a higher incidence of tumor recurrence and its prognosis still remains unsatisfactory. Consolidated therapy for ependymoma includes surgery followed by focal radiotherapy when resection is incomplete. In the case of relapse treatment, options are limited especially for patients who have already received radiotherapy. We sought to establish the feasibility of administering low-dose oral etoposide (50 mg/m(2)/day for 21 days) in combination with the implantation of intracavitary carmustine (BCNU) wafers (Gliadel) at the gross total resection for achieving synergistic treatment in three children affected by recurrent anaplastic ependymoma. All patients had Karnofsky performance scale (KPS) scores >80%. The therapy was tolerated safely and well in all patients without any post-surgery complications. After BCNU wafer implantation, all patients achieved radiological and clinical stabilization for an average period of 3 months. Two patients relapsed after 4 months as shown in brain MRIs. The other patient went to progression two months after the Gliadel implantation. This multimodal approach was not effective for the treatment of refractory anaplastic ependymoma and further studies are required in order to define the role of the combination of multidrug systemic chemotherapy with BCNU wafer implantation in children with high-risk brain tumors.

Speech-language and hearing complaints of children and adolescents with brain tumors

Central nervous system (CNS) tumors generally leave sequelae that may compromise speech, language, swallowing, hearing, and voice functions. This report describes the incidence of speech-language and hearing complaints and disorders in children and adolescents with CNS tumor under treatment at one of the most important Brazilian reference center for pediatric cancer. One-hundred ninety patients were examined for speech-pathology screening and analysis: forty-two percent presented with complaints and symptoms. From the remaining patients, 68% presented clinical symptoms and 32% were actually free from any speech-language and hearing-related symptoms. The high incidence of complaints and symptoms indicate that these patients might benefit from specific rehabilitation interventions.

Phase 2 study of temozolomide in children and adolescents with recurrent central nervous system tumors: a report from the Children's Oncology Group

BACKGROUND

Effective chemotherapy is lacking for most types of central nervous system (CNS) tumors in children. Temozolomide, an agent with activity against adult brain tumors, was investigated in children and adolescents with recurrent CNS tumors.

METHODS

Temozolomide was administered orally as monthly 5-day courses at doses of 200 mg/m(2)/d (patients with no prior craniospinal irradiation [CSI]) or 180 mg/m(2)/d (prior CSI). Patients with a complete (CR) or partial (PR) response or stable disease (SD) could continue temozolomide for up to 12 cycles.

RESULTS

The cohort comprised 122 patients, including 113 with CNS tumors. Median age was 11 years (range, 1-23 years). Among 104 evaluable patients with CNS tumors, 5 PRs and 1 CR were observed. PRs occurred in 1 of 23 evaluable patients with high-grade astrocytoma, 1 of 21 with low-grade astrocytoma, and 3 of 25 with medulloblastoma/primitive neuroectodermal tumor (PNET). The CR occurred in an additional patient with medulloblastoma/PNET. No responses were observed in patients with ependymoma, brain-stem glioma, or other CNS tumors. Notably, 41% of patients with low-grade astrocytoma had SD through 12 courses. The most frequent toxicities were grade 3 or 4 neutropenia (19%) and thrombocytopenia (25%); nonhematologic toxicity was infrequent.

CONCLUSIONS

Although overall objective responses were limited, further exploration of temozolomide may be warranted in children with medulloblastoma and other PNETs, or in patients with low-grade astrocytoma, perhaps in a setting of less pretreatment than the patients in the current study, or in the context of multiagent therapy.

Recurrent ependymoma treated with high-dose tamoxifen in a peripubertal female: Impact on tumor and the pituitary-ovarian axis

Due to high rates of recurrence, the prognosis of childhood ependymoma remains guarded. Anecdotal evidence suggests that tamoxifen may have a role in the treatment of these tumors. We present a case of a child with recurrent ependymoma treated with tamoxifen who showed tumor regression on two separate occasions. However, treatment with tamoxifen resulted in the development of large ovarian cysts associated with supraphysiological plasma concentrations of estradiol.

Childhood intracranial ependymoma: twenty-year experience from a single institution

BACKGROUND

Because few large studies of pediatric ependymoma treatment are available, the authors believed that a retrospective review of treatment outcomes from a single institution would yield potentially valuable information regarding potential prognostic factors. In this article, they report their 20-year institutional experience with this disease.

METHODS

Medical records were reviews of patients with intracranial ependymoma who received their initial treatment at the Children's Hospital of Philadelphia (CHOP)/Hospital of the University of Pennsylvania (HUP) between January 1980 and December 2000. Of the 61 patients who were identified, 49 patients underwent primary therapy at CHOP/HUP and formed the basis for the study. Actuarial overall survival (OS) and progression-free survival (PFS) were determined by the Kaplan-Meier method. Univariate and multivariate analyses were performed using the log-rank test and Cox proportional-hazards models.

RESULTS

With median follow-up of 110.2 months, the 5-year OS and PFS rates were 66.2% and 40.7%, respectively. Older age and higher radiation dose significantly predicted for improved OS. Anaplastic histology predicted for decreased PFS. Cervical spinal cord extension resulted in decreased OS primarily caused by failures outside the primary site. Patients who had a favorable prognosis (aged >/=3 years, no dissemination or cord extension, complete resection, and radiation dose >/=54 grays [Gy]) had 5-year OS and PFS rates of 83.1% and 60.6%, respectively.

CONCLUSIONS

In this study of patients with pediatric intracranial ependymoma, OS and PFS rates were concordant with the rates published in other modern series. The finding of a dose response up to 54 Gy supported the current trend toward dose escalation. Tumor extension to the cervical spine was identified as a predictor for failure outside of the primary site. Although the survival rates were encouraging, there is still significant room for improvement in the management of this disease.

Multi-disciplinary treatment of a rare pelvic cavity ependymoma

Ependymomas usually develop from neuroectodermal organs. Here, we present an ependymoma arising from the pelvic cavity. A 27-year-old Korean female was admitted to the hospital with a sensation of abdominal fullness. Imaging studies revealed a huge heterogeneous nodular mass in the pelvis and lower abdomen. Laparotomy showed that two large masses with multiple nodules were located between the uterus and rectum and uterus and bladder, respectively. Histologically, the tumor was characterized by compact columnar neoplastic cells divided by fibrovascular septae. The neoplastic cells formed true ependymal rosettes and perivascular pseudorosettes. Immunohistochemical staining showed a strong positive reaction for glial fibrillary acidic protein (GFAP) and vimentin and a partial positive reaction for S100 and EMA. The tumor was thus diagnosed as an ependymoma arising from the pelvic cavity. The patient was treated with a debulking operation and chemotherapy based upon the in vitro chemosensitivity test results. The patient was free of cancer for 4 years following surgery. This is a rare case of extraneural ependymoma for which an in vitro chemosensitivity test was critical in determining the multidisciplinary approach for treatment.

Primary postoperative chemotherapy without radiotherapy for intracranial ependymoma in children: the UKCCSG/SIOP prospective study

BACKGROUND

Over half of childhood intracranial ependymomas occur in children younger than 5 years. As an adjuvant treatment, radiotherapy can be effective, but has the potential to damage the child's developing nervous system at a crucial time-with a resultant reduction in IQ and cognitive impairment, endocrinopathy, and risk of second malignancy. We aimed to assess the role of a primary chemotherapy strategy in avoiding or delaying radiotherapy in children younger than 3 years with intracranial ependymoma.

METHODS

Between December, 1992, and April, 2003, we enrolled 89 children with ependymoma who were aged 3 years or younger at diagnosis, of whom nine had metastatic disease on pre-operative imaging. After maximal surgical resection, children received alternating blocks of myelosuppressive and non-myelosuppressive chemotherapy every 14 days for an intended duration of 1 year. Radiotherapy was withheld unless local imaging (ie, from the child's treatment centre) showed progressive disease.

FINDINGS

50 of the 80 patients with non-metastatic disease progressed, 34 of whom were irradiated for progression. The 5-year cumulative incidence of freedom from radiotherapy for the 80 non-metastatic patients was 42% (95% CI 32-53). With a median follow-up of 6 years (range 1.5-11.3), overall survival for the non-metastatic patients at 3 years was 79.3% (95% CI 68.5-86.8) and at 5 years 63.4% (51.2-73.4). The corresponding values for event-free survival were 47.6% (36.2-58.1) and 41.8% (30.7-52.6). There was no significant difference in event-free or overall survival between complete and incomplete surgical resection, nor did survival differ according to histological grade, age at diagnosis, or site of disease. In 47 of 59 (80%) patients who progressed, relapse resulted from local control only. The median time to progression for the 59 patients who progressed was 1.6 years (range 0.1-10.2 years). The median age at irradiation of the whole group was 3.6 years (range 1.5-11.9). For the 80 non-metastatic patients, the 23 who achieved the highest relative dose intensity of chemotherapy had the highest post-chemotherapy 5-year overall survival of 76% (95% CI 46.6-91.2), compared with 52% (33.3-68.1) for the 32 patients who achieved the lowest relative dose intensity of chemotherapy.

INTERPRETATION

This protocol avoided or delayed radiotherapy in a substantial proportion of children younger than 3 years without compromising survival. These results suggest, therefore, that primary chemotherapy strategies have an important role in the treatment of very young children with intracranial ependymoma.

Outcome for children <4 years of age with malignant central nervous system tumors treated with high-dose chemotherapy and autologous stem cell rescue

BACKGROUND

Children <4 years of age (yo) with malignant central nervous system (CNS) tumors have a dismal prognosis. In an attempt to delay or obviate radiation therapy (XRT) and improve outcome, our institution has treated children <4 yo with newly diagnosed malignant CNS tumors with high-dose chemotherapy (HDC) and autologous stem cell rescue (ASCR) followed by selective XRT.

PROCEDURE

Fifteen children (age 4-38 months) with malignant CNS tumors have completed treatment with HDC/ASCR. All patients received three cycles of induction chemotherapy (cisplatin 3.5 mg/kg- day 0, cyclophosphamide 60 mg/kg- day 1 and 2, etoposide 2.5 mg/kg- day 0-2, vincristine 0.05 mg/kg, day 0, 7, 14) followed by three cycles of HDC (carboplatin 17 mg/kg and thiotepa 6 mg/kg, day 0 and 1) with ASCR. Histology included five medulloblastomas, four primitive neuroectodermal tumors (PNET), five malignant gliomas, and one ependymoma. Outcome and treatment toxicities were evaluated by retrospective chart review.

RESULTS

Median follow-up time of the 15 patients is 22 months (range 8-82 months). The 1- and 2-year progression-free survival (PFS) is 86.1% and 52.2% and overall survival (OS) 91.6% and 72.1%, respectively. Ten patients are alive and disease free 3-77 months (median 18 months) after having completed HDC/ASCR, thereoff five received XRT. Toxicity was primarily myelosuppression. There was no treatment mortality.

CONCLUSIONS

We are encouraged by the outcome of 15 children <4 yo with malignant CNS tumors treated with tandem cycles of HDC and ASCR at our institution. The treatment regimen is relatively well tolerated.

Successful treatment of intracranial ependymoma with leptomeningeal spread with systemic chemotherapy and intrathecal liposomal cytarabine in a two-year-old child

Ependymoma is the third most common CNS tumor in children. Neuraxis dissemination at the time of diagnosis is rare and occurs in fewer than 10% of patients. Recent advances in neuroimaging, neurosurgery, and radiation therapy have improved disease control and functional outcomes for children with ependymoma. However, children under the age of 3 years with ependymoma and leptomeningeal spread historically have had worse outcomes. It is not clear if age alone, or a combination of risk factors such us unfavorable location, which may prevent gross total resection, and withholding radiation therapy may have contributed to poor outcomes in younger age groups. The reason for attempting GTR is based on results from retrospective and prospective studies, where the most important prognostic factor is extent of resection. These patients are not candidates for craniospinal irradiation. Therefore, new therapeutic approaches must be attempted. This is a case report of a posterior fossa ependymoma with leptomeningeal dissemination in a two-year-old child, successfully treated with dose intensive chemotherapy and intrathecal liposomal cytarabine.

Malignant spinal cord compression in cancer patients may be mimicked by a primary spinal cord tumour

Although it is quite rare, second primary neoplasms in cancer patients may present with the signs and symptoms of malignant spinal cord compression. Primary spinal cord tumours in the cancer patients may be deceptive and considered as the recurrent first cancer. Therefore, it should be precisely differentiated and appropriately managed. We report such a case of intramedullary ependymoma of the cervical spinal cord mimicking metatstatic recurrent lymphoma and causing cord compression. A 50-year-old man developed intramedullary ependymoma of the cervical spinal cord 1.5 years following chemoradiation for Waldeyer's ring lymphoma. He presented with a 2-month history of neck pain, progressive upper- and lower-extremity numbness and weakness, and bowel and bladder dysfunction. Magnetic resonance imaging revealed an intramedullary expansive lesion extending from C4 to C6 levels of the cervical spinal cord. The clinical and radiological findings were suggestive of malignant process. A comprehensive investigation failed to detect another site of disease. He underwent operation, and the tumour was subtotally resected. The patient's neurological deficits improved subsequently. The development of the intramedullary ependymoma following treating lymphoma has not been reported. We describe the clinical, radiological and pathological findings of this case and review the literature.

[Gliomas in adults: primary non-surgical treatment]

900 to 1000 new cases of primary brain tumour occur each year in Denmark, and half of them are gliomas. The treatment is cytoreductive surgery, followed by radiation therapy and chemotherapy. Radiation therapy has a definite place in the treatment of low-grade gliomas, but the timing is a matter of dispute. Patients with Glioblastoma Multiform should be treated with concomitant radiation therapy and temozolamide, followed by adjuvant temozolamide. Anaplastic astrocytomas should be treated with postoperative radiation therapy with or without adjuvant chemotherapy. Anaplastic oligodendroglioma should be treated with radiation therapy only.

Thallium-201SPECT assessment in the detection of recurrences of treated gliomas and ependymomas

INTRODUCTION

The aim of this study was to establish the value of thalium-(201) single-photon emission computed tomography ((201)Tl-SPECT) in the detection of recurrences in the follow-up of patients with treated primary neuroepithelial tumours.

MATERIAL AND METHODS

Sixty-three (201)Tl-SPECT were performed in 36 patients with glioma (12 males, mean age of 46 +/- 13 years). All patients underwent surgery and adjuvant radiotherapy (and some of them received chemotherapy). All patients were submitted to morphological neuroimaging techniques as well (and (201) Tl-SPECT). Mean follow-up was 18.3 +/- 14.6 months. Gold standard was based on clinical follow-up, therapeutical decisions (at least 4 months after (201)Tl-SPECT) and imaging features.

RESULTS

Sensitivity and specificity of (201)Tl-SPECT to detect glioma recurrences were 90% and 100% respectively and 93% accuracy. Sensitivity and specificity for high grade tumours, were 100% respectively. Due to 4 false negatives, sensitivity and specificity for low grade gliomas were 78% and 100%. In the positive (201)Tl-SPECT group of patients overall survival was 13.64% at the end of the study. The negative (201)Tl-SPECT group had 84.62% overall survival at the end of the study (p = 0.0003). CONCLUSIONS. (201)Tl-SPECT is a valuable and noninvasive diagnostic procedure to detect recurrence or progression disease for treated gliomas and ependymomas. (201)Tl-SPECT has a good correlation with short term prognosis with excellent diagnostic accuracy.

Recurrence of brain tumours in patients treated with growth hormone: analysis of KIGS (Pfizer International Growth Database)

BACKGROUND

Growth hormone (GH) has been used successfully in the treatment of short stature secondary to GH deficiency in survivors of childhood brain tumours. There has been concern that GH might increase the risk of recurrence.

AIM

To analyse KIGS (Pfizer International Growth Database) with respect to tumour recurrence in patients with brain tumours.

METHODS

Data for tumour recurrence were analysed retrospectively in 1038 patients with craniopharyngiomas, 655 with medulloblastomas, 113 with ependymomas, 297 with germinomas, and 400 with astrocytomas or gliomas. All patients had received recombinant human GH (Genotropin, Pfizer Inc.).

RESULTS

Recurrence-free survival rates were 63% at a follow-up of 10.3 y in craniopharyngioma, 69% in 9.1 y in the glial tumours, 71% in 7.4 y in germinomas, 92% in 4.6 y in medulloblastomas and 89% in 2.5 y in ependymomas. Dose of GH and treatment modalities did not differ significantly between patients with and without recurrence.

CONCLUSION

Tumour recurrence rates in surviving patients with brain tumours receiving GH treatment do not appear to be increased compared with published reports. However, longer follow-up regarding recurrences and secondary neoplasms remains essential.

Acquired amnesia in childhood: a single case study

We report the case of C.L., an 8-year-old child who, following the surgical removal of an ependymoma from the left cerebral ventricle at the age of 4 years, developed significant difficulties in retaining day-to-day events and information. A thorough neuropsychological analysis documented in C.L. a severe anterograde amnesic syndrome, characterised by normal short-term memory, but poor performance on episodic long-term memory tests. In particular, C.L. demonstrated virtually no ability to recollect new verbal information several minutes after the presentation. As for semantic memory, C.L. demonstrated general semantic competencies, which, depending on the test, ranged from the level of a 6-year-old girl to a level corresponding to her actual chronological age. Finding a patient who, despite being severely impaired in the ability to recollect new episodic memories, still demonstrates at least partially preserved abilities to acquire new semantic knowledge suggests that neural circuits implicated in the memorisation of autobiographical events and factual information do not overlap completely. This case is examined in the light of growing literature concerned with the dissociation between episodic and semantic memory in childhood amnesia.

Salvage treatment for childhood ependymoma after surgery only: Pitfalls of omitting “at once” adjuvant treatment

PURPOSE

To discuss the results obtained by giving adjuvant treatment for childhood ependymoma (EPD) at relapse after complete surgery only.

METHODS AND MATERIALS

Between 1993 and 2002, 63 children older than 3 years old entered the first Italian Association for Pediatric Hematology and Oncology protocol for EPD (group A), and another 14 patients were referred after relapsing after more tumor excisions only (group B). Prognostic factors were homogeneously matched in the two groups. We report on the outcome of group B.

RESULTS

Mean time to first local progression in group B had been 14 months. Tumors originated in the posterior fossa (PF) in 10 children and were supratentorial (ST) in 4; 11 had first been completely excised (NED) and 3 had residual disease (ED). Diagnoses were classic EPD in 9 patients, anaplastic in 5. Eight children were referred NED and 6 ED after two or more operations, 5 had cranial nerve palsy, 1 had recurrent meningitis, and 2 had persistent hydrocephalus. All received radiotherapy (RT) to tumor bed and 5 also had pre-RT chemotherapy. Six of 14 patients (6/10 with PF tumors) had a further relapse a mean 6 months after the last surgery; 4 of 6 died: progression-free survival and overall survival at 4 years after referral were 54.4% and 77%, respectively. Considering only PF tumors and setting time 0 as at the last surgery for group B, progression-free survival and overall survival were 32% and 50% for group B and 52% (p < 0.20)/70% (p < 0.29) for the 46 patients in group A with PF tumors. Local control was 32% in group B and 70.5% in group A (p = 0.02).

CONCLUSIONS

Relapsers after surgery only, especially if with PF-EPD, do worse than those treated after first diagnosis; subsequent surgery for tumor relapse has severe neurologic sequelae.

Toxicity profile of delayed high dose sodium thiosulfate in children treated with carboplatin in conjunction with blood-brain-barrier disruption

PURPOSE

To assess the safety of delayed high dose intravenous (i.v.) sodium thiosulfate (STS) in a case series of 12 children with malignant brain tumors who were treated with intraarterial (i.a.) carboplatin in conjunction with blood-brain-barrier disruption (BBBD).

METHODS

Twelve children ages 17 months-12 years underwent a total of 132 BBBD chemotherapy treatments and also received delayed high dose STS (i.v.). Dose 1 of STS (10-16 g/m(2)) was administered 2 or 4 hr after carboplatin, and a second STS dose was administered 4 hr after dose 1 if the child had impaired baseline hearing. Toxicity data were graded in accordance with the National Cancer Institute Common Toxicity Criteria (Version 2). Audiologic monitoring to evaluate the otoprotective potential of STS was performed on 11 children. Ototoxicity was defined in accordance with the American Speech-Language-Hearing Association (ASHA) criteria. Baseline and end of treatment hearing status were graded using Brock's criteria.

RESULTS

Nausea and vomiting were well controlled with anti-emetics administered approximately 30 min prior to STS infusion. Analogous to results in adult patients, there was mild transient hypernatremia and a trend for improved protection from ototoxicity in children who received STS delayed to 4 hr post-treatment versus 2 hr. Tumor responses were seen in heavily pre-treated patients with relatively chemo-resistant tumors, suggesting that STS did not protect the tumor from platinum cytotoxicity.

CONCLUSION

High dose STS is well tolerated in children under 12 years of age. Further studies of STS in children are warranted to assess otoprotection and the impact of STS on platinum mediated efficacy.

[Megachemotherapy and autologous hematopoietic stem cell transplantation in children with solid tumours excluding neuroblastoma--experience of Polish paediatric centres]

AIM OF THE STUDY was to present the experience of four Polish transplantation centres (Wroclaw, Bydgoszcz, Kraków and Lublin) with use of megachemotherapy (MCT) and autologous hematopoietic stem cell transplantation (autoHSCT) in children with high risk solid tumours.

PATIENTS AND METHODS

Between 1994 and 2005 in 67 patients, whose age ranged form 1.5 to 20 years, 74 procedures of megachemotherapy and auto HSCT were performed. 25 children were treated for Ewing Sarcoma, 13 for rhabdomyosarcoma embryonale (RMS), 7 for germinal tumours, 6 for medulloblastoma, 4 for PNET, 4 for Wilm's tumours, 2 for glioblastoma and single patients with mesenchymoma, astrocytoma, ependymoma, angioblastoma, carcinoma ovarian and carcinoma embryonale glutei. Most common megachemotherapy protocols consisted of: Melphalan, Etopozyd i Carboplatin (MEC)--applied in 24 children and Busulfan plus Melphalan (Bu Mel) administered in 19 patients. In 29 children MCH was introduced in first complete remission, in 14 the procedure was performed in second or subsequent remission and 24 patients did not achieve remission before megachemotherapy was started.

RESULTS

30 children are alive (44%), 28 of them in complete remission of disease. 23 out of 29 (79%) patients were transplanted in first complete remission and median observation time in that group is 29 months (range 2-74 months). Only 5 out of 38 children transplanted in second complete remission or without complete remission survived. 39 patients relapsed at a median time 11 months after MCT and 37 of them subsequently died of disease at a median time of 16 months. One toxic death was noted--it was a boy, transplanted with progressive disease.

CONCLUSIONS

1. Megachemotherapy with autologous stem cell can rescue children with high risk solid tumours. It is a safe procedure especially when performed in remission. 2. Children with resistant or relapsed solid tumours are unlikely to benefit from megachemotherapy.

Phase I trial of intrathecal spartaject busulfan in children with neoplastic meningitis: a Pediatric Brain Tumor Consortium Study (PBTC-004)

PURPOSE

A phase I trial of intrathecal Spartaject Busulfan (SuperGen, Inc., San Ramon, CA) was conducted in children with neoplastic meningitis following recurrent primary brain tumors to describe toxicities, estimate the maximum tolerated dose (MTD), and document evidence of responses to this agent.

EXPERIMENTAL DESIGN

The continuous reassessment method was used to assign cohorts of patients to doses of intrathecal Spartaject Busulfan via an Ommaya reservoir and/or lumbar puncture twice weekly for 2 weeks followed by an assessment of toxicity and response. Patients with stable disease or an objective response continued to receive intrathecal Spartaject Busulfan plus systemic chemotherapy at regular intervals. Cerebrospinal fluid and blood were obtained for pharmacokinetic studies in patients with Ommaya reservoirs after the first dose of intrathecal Spartaject Busulfan. Seven evaluable patients were assigned to the starting dose of 5 mg, two patients to 7.5 mg, three patients to 10 mg, seven patients to 13 mg, and four patients to 17 mg.

RESULTS

Between September 2000 and May 2003, 28 patients were enrolled in this study. Twenty-three patients (median age, 8.8 years; range, 2.5-19.5 years) were evaluable for estimating the MTD, and dose-limiting toxicities were observed in three and included grade 3 vomiting (n = 1 at 5 mg), grade 3 headache (n = 1 at 17 mg), and grade 3 arachnoiditis (n = 1 at 17 mg). Pharmacokinetic data showed that post-infusion concentrations of busulfan ranged from 50 to 150 microg/mL and declined to <1 microg/mL within 5 hours.

CONCLUSIONS

Intrathecal Spartaject Busulfan was well tolerated in children with neoplastic meningitis from brain tumors, and the recommended dose for future phase II studies is 13 mg.

Spinal myxopapillary ependymoma outcomes in patients treated with surgery and radiotherapy at M.D. Anderson Cancer Center

This study was undertaken to determine the disease outcomes in patients treated with surgery alone or surgery and adjuvant radiotherapy (RT) for myxopapillary ependymoma (MPE) of the spine. The medical records of 35 patients with MPE treated at The University of Texas M.D. Anderson Cancer Center between December 1968 and July 2002 were reviewed. The endpoints analyzed were progression-free survival (PFS), overall survival, and local control. The median age of patients was 35 years (range, 14-63 years), and the male to female ratio was 2.5:1. In total, 21 (60%) patients underwent a gross total resection, 13 (37%) a subtotal resection, and 1 (3%) a biopsy only; 22 of them (63%) also received adjuvant RT. The median follow-up was 10.7 years. The 10-year overall survival, PFS, and local control rates for the entire group were 97%, 62%, and 72%, respectively. Of 11 patients 5 (45%) who had undergone gross total resection alone had recurrence. A total of 12 (34%) patients had disease recurrence, all in the neural axis; 8 of them had treatment failure at the primary site only, 3 in the distant neural axis only, and 1 at the primary site and in the distant neural axis. Patient age (> 35 years; P = 0.002) and adjuvant RT (P = 0.04) significantly affected PFS. The long-term patient survival duration for MPE managed with surgery and adjuvant RT is favorable. Regardless of the extent of resection, adjuvant RT appears to significantly reduce the rate of tumor progression. Failures occurred exclusively in the neural axis, mainly at the primary site.

Ependymoma: new therapeutic approaches including radiation and chemotherapy

Recent advances in neuroimaging, neurosurgery and radiation therapy have improved disease control and functional outcomes for children with ependymoma, including children under the age of 3 years. The rate of gross-total resection has been increased to 85% in some series and 3 year progression-free survival after radiation therapy as high as 75% has been reported along with significant reductions in neurologic, endocrine and cognitive deficits. Based on these advances and renewed interest in radiation therapy as a frontline treatment modality, attention has been refocused on disease control instead of radiotherapy avoidance. Future research in the treatment of this tumor, that afflicts fewer than 200 children in the US each year, will focus on molecular biology, clarifying risk factors for tumor control and late effects, and testing novel agents.