Prognostic factors in childhood ependymomas

Patterns of relapse for children with localized intracranial ependymoma

We examined patterns of relapse and prognostic factors in children with intracranial ependymoma. Records of 82 children diagnosed with localized intracranial ependymoma were reviewed. 52% first presented to our institution after relapse. Median age at initial diagnosis was 4 years (range 0-18 years). Gender was 55% male. Initial tumor location was infratentorial in 71% and supratentorial in 29%. Histology was WHO Grade II in 32% and Grade III in 68%. As part of definitive management, 99% had surgery, 70% received RT (26% 2D/3D-conformal RT[CRT], 22% intensity-modulated RT [IMRT], 22% proton), and 37% received chemotherapy. Median follow-up was 4.6 years (range 0.2-32.9). Overall, 74% of patients relapsed (50% local, 17% distant, 7% local + distant) at a median 1.5 (range 0.1-17.5) years. Five-year OS and FFS for patients presenting prior to relapse are 70% (95% confidence interval [CI], 50-83%) and 48% (95% CI 30-64%), respectively. On log-rank, superior overall survival (OS) was demonstrated for gross total resection (p = 0.03). Superior failure-free survival (FFS) was demonstrated for age < 5 years (p = 0.04). No difference in OS or FFS was found between 2D/3D-CRT versus IMRT/proton (p > 0.05). On multivariate analysis, age ≤ 5 was independently associated with a lower risk of death and failure versus older patients (p < 0.05). Contrary to previous reports, young age may not be a poor prognostic factor in patients who can tolerate intensive treatment. Future studies examining patients stratified by clinical and molecular attributes are warranted.

Pediatric Ependymoma

Over the past 150 years since Virchow's initial characterization of ependymoma, incredible efforts have been made in the classification of these tumors and in the care of pediatric patients with this disease. While the advent of modern neurosurgery and the optimization of radiation have provided significant gains, a more complex but incomplete picture of pediatric ependymomas has begun to form through a combination of international collaborations and detailed genetic and histologic characterizations. This review includes and synthesizes the clinical understanding of pediatric ependymoma and their developing molecular insight into what is truly a family of malignancies in which distinct members require different surgical approaches, radiation plans, and targeted therapies.

Microsurgical management of pediatric ependymomas of the fourth ventricle via the trans-cerebellomedullary fissure approach: A review of 26 cases

In the present study, the microsurgical management of 26 ependymomas of the fourth ventricle in children via the trans-cerebellomedullary fissure (CMF) approach was reviewed and evaluated. Clinical data were obtained from 26 ependymomas of the fourth ventricle treated with microsurgery using the trans-CMF approach from March 2006 to September 2010 at the Department of Neurosurgery of The First Affiliated Hospital of China Medical University (Shenyang, China). These data were collected and analyzed. Suboccipital median posterior fossa craniotomy and trans-CMF approach were performed in all cases for the microsurgical removal of the tumors. An additional incision was performed in the inferior medullary velum of 5 patients, in order to obtain adequate exposure of the tumors. As a result, all tumors were well exposed during surgery. Gross total resection (GTR) was achieved in 22 cases, near total resection (NTR) in 3 cases and subtotal resection (STR) in 1 case. All excised tumors were pathologically confirmed. No mortality occurred intraoperatively, and no patient presented with mutism or any other surgery-related complications. One patient suffered from postoperative hydrocephalus and received ventriculoperitoneal shunting, which relieved the symptoms. Over the 3.0-7.5-year follow-up period (mean, 4.8 years), tumor relapse occurred in 1 case with GTR, 2 cases with NTR and 1 case with STR. In total, 3 patients succumbed to tumor relapse and 4 were lost to follow-up. According to the literature and the clinical experience of the present authors, the trans-CMF approach provides safe and sufficient access to the fourth ventricle without the requirement of an incision in the inferior vermis. This approach prevents damage to the normal cerebellum and improves the surgical outcome. Tumor removal, restoration of cerebrospinal fluid circulation and preservation of brainstem function are factors that should be taken into consideration during surgery. For patients with residual tumors, adjuvant radiotherapy and/or chemotherapy may be beneficial.

Advances in Radiation Therapy in Pediatric Neuro-oncology

Radiation therapy remains a highly effective therapy for many pediatric central nervous system tumors. With more children achieving long-term survival after treatment for brain tumors, late-effects of radiation have become an important concern. In response to this problem, treatment protocols for a variety of pediatric central nervous system tumors have evolved to reduce radiation fields and doses when possible. Recent advances in radiation technology such as image guidance and proton therapy have led to a new era of precision treatment with significantly less exposure to healthy tissues. These developments along with the promise of molecular classification of tumors and targeted therapies point to an optimistic future for pediatric neuro-oncology.

Evaluation of chromosome 1q gain in intracranial ependymomas

Ependymomas are relatively uncommon gliomas with poor prognosis despite recent advances in neurooncology. Molecular pathogenesis of ependymomas is not extensively studied. Lack of correlation of histological grade with patient outcome has directed attention towards identification of molecular alterations as novel prognostic markers. Recently, 1q gain has emerged as a potential prognostic marker, associated with decreased survival, especially in posterior fossa, high grade tumors. Cases of intracranial ependymomas were retrieved. Tumors were graded using objective criteria to supplement WHO grading. Fluorescence in situ hybridization for 1q gain was performed on formalin-fixed paraffin embedded sections. Eighty-one intracranial ependymomas were analyzed. Pediatric (76%) and infratentorial (70%) ependymomas constituted the majority. 1q gain was seen in 27 cases (33%), was equally frequent in children (34%) and adults (32%), supratentorial (37%) and infratentorial (32%) location, grade II (33%) and III (25%) tumors. Recurrence was noted in 24 cases and death in 7 cases with 5-year progression-free and overall-survival rates of 37% and 80%, respectively. Grade II tumors had a better survival than grade III tumors; histopathological grade was the only prognostically significant marker. 1q gain had no prognostic significance. 1q gain is frequent in ependymomas in Indian patients, seen across all ages, sites and grades, and thus is likely an early event in pathogenesis. The prognostic value of 1q gain, remains uncertain, and multicentric pooling of data is required. A histopathological grading system using objective criteria correlates well with patient outcome and can serve as an economical option for prognostication of ependymomas.

Malignant Transformation of Grade II Ependymoma in a 2-Year-Old Child: Case Report

Ependymomas are central nervous system neoplasms that account for a third of all posterior fossa tumors in children. The most common location for infratentorial ependymoma is within the fourth ventricle. We present a case report of malignant transformation of an infratentorial grade II ependymoma in a 2-year-old child who presented with vomiting and visual disturbance. An infratentorial brain tumor in the left cerebellar area was totally removed, and the initial pathologic diagnosis was grade II ependymoma. The tumor recurred aggressively 1 year later; subtotal removal and adjuvant chemotherapy were performed. After a second operation, a histopathologic study was performed. The second specimen was defined as a grade III anaplastic ependymoma. Transformation to grade III anaplastic ependymoma is possible for a grade II ependymoma but very rare. The diagnosis of the anaplastic variant of intracranial ependymomas is difficult. Surgical treatment remains the mainstay of the treatment for all cases. Ependymomas in young infants have a worse prognosis than older children, so we need individual clinical evaluation and close follow-up of such cases. This article highlights the requirement of a close follow-up for grade II ependymomas for anaplastic transformation.

A retrospective analysis of recurrent intracranial ependymoma

BACKGROUND

Recurrence occurs in almost 50% of patients with intracranial ependymoma, and their outcome following recurrence is poor.

METHODS

We retrospectively reviewed the medical records of 22 patients with intracranial ependymoma and subsequent relapse(s) (59 recurrences) treated at Children's Hospital Los Angeles or New York University between January 1997 and December 2012.

RESULTS

Median duration of follow-up was 52 months (7-171 months). Median age at initial diagnosis was 4 years (0.3-19 years) with 8 patients younger than 3 years at presentation. Eleven patients had anaplastic and 11 cellular pathologies. Eighteen patients had infratentorial tumors at diagnosis and 3 (all infratentorial) had metastatic spinal cord involvement at presentation. Cerebrospinal fluid involvement was not identified at diagnosis or relapse. Median time to first recurrence was 16 months (1.3 to 115 months). The number of recurrences in each patient ranged from 1 to 9 (median = 2). Thirty-seven recurrences (63%) were detected asymptomatically by surveillance imaging. Fifteen recurrences (26%) arose outside the initial tumor site. Recurrences were treated by surgical resection (45), with irradiation (30), and with various oral chemotherapies (23) with (7) or without (16) conventional chemotherapy. The 5 and 10 year overall survival rates from first recurrence were 0.37 ± 0.14 and 0.25 ± 0.14.

CONCLUSION

Prolonged (5-10 year) survival from first relapse was noted in over one-quarter of our patients. It remains unclear whether early radiographic diagnosis, differing treatment modalities beyond radical surgical resection or possibly unrecognized biological differences contributed towards this prolonged survival.

Role of stereotactic radiosurgery and fractionated stereotactic radiotherapy in the management of intracranial ependymoma

Ependymoma accounts for 5-10% of all childhood CNS tumors and less than 5% of intracranial tumors in adults. Ependymomas typically have a sharp tumor-brain parenchyma interface and this characteristic lends itself well to stereotactic radiation delivery. Data on the use of stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) for ependymoma in various settings have emerged over the past 10 years. SRS has been used in recurrent disease and as a boost after external beam radiation therapy. FSRT has been used in pediatric brain tumors and can potentially limit the long-term toxicities associated with radiation therapy by reducing the amount of normal brain parenchyma treated. Long-term follow-up is needed to determine the long-term efficacy and toxicities associated with these treatment modalities.

Supratentorial gross-totally resected non-anaplastic ependymoma: population based patterns of care and outcomes analysis

Observation following gross-total resection (GTR) for non-anaplastic supratentorial ependymomas is often advocated based on small, retrospective series. The purpose of this study is to perform a population-based analysis to examine outcomes for this rare cohort of low-risk patients. A retrospective analysis was conducted utilizing the Surveillance, Epidemiology and End Results Program of the United States National Cancer Institute. We identified patients with supratentorial non-anaplastic ependymoma who underwent GTR alone or GTR followed by radiation. We identified 92 patients who met these criteria. The median age was 17.5 years (range 1-83) with the majority female (58 %) and white (75 %). Radiotherapy (RT) was delivered in half of patients. The 5-/10-year Kaplan-Meier estimated overall survival (OS) and cause-specific survival (CSS) for the overall cohort was 83.2/71.4 and 84.1/78.0 %, respectively. There was no evidence of decreased CSS (HR 0.52 [0.18-1.51]; p = 0.23) or OS (HR 0.63 [0.25-1.59]; p = 0.33) with the omission of RT on univariate analysis. Age ≥18 years correlated with worse OS (HR 4.01 [1.45-11.11]; p = 0.008) and CSS (HR 2.86 [0.99-8.31]; p = 0.05). RT did not impact outcome for this low-risk cohort of patients. Older age correlates with poor prognosis.

United Kingdom 30-day mortality rates after surgery for pediatric central nervous system tumors

OBJECT

In an increasing culture of medical accountability, 30-day operative mortality rates remain one of the most objective measurements reported for the surgical field. The authors report population-based 30-day postoperative mortality rates among children who had undergone CNS tumor surgery in the United Kingdom.

METHODS

To determine overall 30-day operative mortality rates, the authors analyzed the National Registry of Childhood Tumors for CNS tumors for the period 2004-2007. The operative mortality rate for each tumor category was derived. In addition, comparison was made with the 30-day operative mortality rates after CNS tumor surgery reported in the contemporary literature. Finally, by use of a funnel plot, institutional performance for 30-day operative mortality was compared for all units across the United Kingdom.

RESULTS

The overall 30-day operative mortality rate for children undergoing CNS tumor surgery in the United Kingdom during the study period was 2.7%. When only malignant CNS tumors were analyzed, the rate increased to 3.5%. One third of the deaths occurred after discharge from the hospital in which the surgery had been performed. The highest 30-day operative mortality rate (19%) was for patients with choroid plexus carcinomas. A total of 20 institutions performed CNS tumor surgery during the study period. Rates for all institutions fell within 2 SDs. No trend associating operative mortality rates and institutional volume was found. In comparison, review of the contemporary literature suggests that the postoperative mortality rate should be approximately 1%.

CONCLUSIONS

The authors believe this to be the first report of national 30-day surgical mortality rates specifically for children with CNS tumors. The study raises questions about the 30-day mortality rate among children undergoing surgery for CNS tumors. International consensus should be reached on a minimum data set for outcomes and should include 30-day operative mortality rates.

Phase II study of pre-irradiation chemotherapy for childhood intracranial ependymoma. Children's Cancer Group protocol 9942: a report from the Children's Oncology Group

PURPOSE

Standard therapy for childhood intracranial ependymoma is maximal tumor resection followed by involved-field irradiation. Although not used routinely, chemotherapy has produced objective responses in ependymoma, both at recurrence and in infants. Because the presence of residual tumor following surgery is consistently associated with inferior outcome, the potential impact of pre-irradiation chemotherapy was investigated.

METHODS

Between 1995 and 1999, the Children's Cancer Group undertook a Phase II trial of pre-irradiation chemotherapy in children 3-21 years of age with intracranial ependymoma and radiological evidence of post-operative residual tumor.

RESULTS

Of 84 patients, 41 had residual tumor, and were given four cycles of cisplatin-based chemotherapy prior to irradiation. Of 35 patients fully evaluable for response to chemotherapy, 14 (40%) demonstrated complete response, 6 (17%) partial response, 10 (29%) minor response or stable disease, and 5 (14%) demonstrated progressive tumor growth. For the entire group, 5-year overall survival (OS) and event-free survival (EFS) was 71 ± 6%, and 57 ± 6%, respectively. The pre-irradiation chemotherapy group demonstrated EFS comparable to that of patients with no residual tumor who received irradiation alone (55 ± 8% vs. 58 ± 9%, P = 0.45). Any benefit of chemotherapy was restricted to patients with greater than 90% tumor resection.

CONCLUSIONS

Children with near total resection of ependymoma may benefit from pre-irradiation chemotherapy. Patients with subtotal resection have inferior outcome despite responses to chemotherapy, and should be considered for second-look surgery prior to irradiation. Pediatr Blood Cancer 2012; 59: 1183-1189. © 2012 Wiley Periodicals, Inc.

Intracranial ependymoma: long-term results in a series of 21 patients treated with stereotactic (125)iodine brachytherapy

Background

We evaluated the long-term outcome in patients harboring intracranial ependymomas treated with interstitial brachytherapy (IBT).

Methods

Twenty-one patients (M/F = 9/12; median age: 29 years; range: 8–70 years), diagnosed with intracranial ependymoma (1 WHO I, 11 WHO II, 9 WHO III) were treated with IBT using stereotactically implanted ¹²⁵Iodine seeds between 1987 and 2010, either primarily, as adjuvant therapy following incomplete resection, or as salvage treatment upon tumor recurrence. Sixteen of 21 patients underwent microsurgical resection prior to IBT; in 5 patients, IBT was performed primarily after stereotactic biopsy for histological diagnosis. The cumulative tumor surface dose ranged from 50–65 Gy treating a median tumor volume of 3.6 ml (range, 0.3–11.6 ml). A median follow-up period of 105.3 months (range, 12.7–286.2 months) was evaluated.

Results

Actuarial 2-, 5- and 10-years overall- and disease-specific survival rates after IBT were each 90% and 100% at all times for ependymomas WHO I/II, for anaplastic ependymomas WHO III 100%, 100%, 70% and 100%, 100%, 86%, respectively. The neurological status of seven patients improved, while there was no change in 12 and deterioration in 2 patients, respectively. Follow-up MR images disclosed a complete tumor remission in 3, a partial remission in 12 and a stable disease in 6 patients. Treatment-associated morbidity only occurred in a single patient.

Conclusions

This study shows that stereotactic IBT for intracranial ependymomas is safe and can provide a high degree of local tumor control. Due to the low rate of side effects, IBT may evolve into an attractive alternative to microsurgery in ependymomas located in eloquent areas or as a salvage treatment.

Super-selective basilar artery infusion of bevacizumab and cetuximab for multiply recurrent pediatric ependymoma

Ependymoma is a central nervous system tumor associated with a poor prognosis due to limited efficacy of current medical treatment modalities, often resulting in multiple surgical re-resections with each tumor recurrence. As traditional chemotherapeutic regimens have proved unsuccessful in long-term control of subtotally resected ependymoma, other agents targeting the tumor microenvironement including the angiogenic factors supplying neovascularization have recently been used. Anti-angiogenic agents such as bevacizumab are routinely used in adult patients with recurrent glioma. Selective intra-arterial cerebral infusion (SIACI) of biological agents within tumor-supplying cerebral vasculature has recently been re-examined as a means to avoid the systemic side-effects associated with intravenous use of bevacizumab. This technical paper describes the first reported use of SIACI for delivery of two targeted biologic agents, bevacizumab and cetuximab in a pediatric patient utilizing the basilar artery to selectively administer the drugs to the tumor microenvironment. We believe this method for therapeutic delivery will both broaden treatment options and better refine treatment methodology as the multi-modality treatment approach often required to treat patients with pediatric ependymomas and other intracranial malignancies evolves.

Histopathological grading of pediatric ependymoma: reproducibility and clinical relevance in European trial cohorts

Background

Histopathological grading of ependymoma has been controversial with respect to its reproducibility and clinical significance. In a 3-phase study, we reviewed the pathology of 229 intracranial ependymomas from European trial cohorts of infants (2 trials - SFOP/CNS9204) and older children (2 trials - AIEOP/CNS9904) to assess both diagnostic concordance among five neuropathologists and the prognostic utility of histopathological variables, particularly tumor grading.

Results

In phase 1, using WHO criteria and without first discussing any issue related to grading ependymomas, pathologists assessed and independently graded ependymomas from 3 of 4 trial cohorts. Diagnosis of grade II ependymoma was less frequent than grade III, a difference that increased when one cohort (CNS9204) was reassessed in phase 2, during which the pathologists discussed ependymoma grading, jointly reviewed all CNS9204 tumors, and defined a novel grading system based on the WHO classification. In phase 3, repeat independent review of two cohorts (SFOP/CNS9904) using the novel system was associated with a substantial increase in concordance on grading. Extent of tumor resection was significantly associated with progression-free survival (PFS) in SFOP and AIEOP, but not in CNS9204 and CNS9904. Strength of consensus on grade was significantly associated with PFS in only one trial cohort (AIEOP). Consensus on the scoring of individual histopathological features (necrosis, angiogenesis, cell density, and mitotic activity) correlated with PFS in AIEOP, but in no other trial.

Conclusions

We conclude that concordance on grading ependymomas can be improved by using a more prescribed scheme based on the WHO classification. Unfortunately, this appears to have utility in limited clinical settings.

Posterior fossa ependymomas: new radiological classification with surgical correlation

PURPOSE

The key determinant of long-term outcome in infratentorial ependymomas remains the extent of surgical resection. We describe a new radiological classification system which is validated against surgical findings and correlated with risk of post-operative residual tumour.

METHODS

Twenty-five consecutive patients (12 females, mean age 4.9 years, range 0.5-17 years) with infratentorial ependymomas were studied. Lesions were classified on pre-operative MRI according to the pattern of extension, brainstem displacement and involvement of the obex, as lateral-type or midfloor-type tumours. Twenty-one operative records were reviewed with respect to the microanatomical tumour origin by a paediatric neurosurgeon, blinded to MRI findings. Follow-up imaging studies were evaluated for residual tumour.

RESULTS

There were 15 cases of midfloor-type tumour (anterior displacement of brainstem, infiltration of obex) and 10 cases of lateral-type tumour (lateral displacement of brainstem, obex free of tumour). Extension into prepontine or cerebellopontine cisterns was more common in lateral-type tumours. Agreement between the radiological classification and tumour origin, as defined by operative records, was seen in 18 out of 20 cases. Risk of residual tumour in lateral-type tumours was more than twice that of midfloor-type tumours (80% vs. 33%, p=0.04). Risk of tumour residual was also significantly higher when vessel encasement or prepontine extension was observed.

CONCLUSIONS

Infratentorial ependymomas can be pre-operatively classified as lateral-type or midfloor-type tumours. This correlates well with operative findings. Lateral-type tumours have significantly increased risk of residual tumour compared to midfloor- type tumours and this may influence intensity of imaging surveillance.

Intracranial and spinal ependymoma: series at Faculdade de Medicina, Universidade de São Paulo

OBJECTIVE

Ependymomas are rare intracranial neuroepithelial tumors and the most common location is intramedullary. The aim was to analyze the characteristics of these tumors to determine the patients' overall survival and the likelihood of recurrence.

METHOD

Data of clinical presentation, tumor location, duration of symptoms, degree of resection and complementary treatment of 34 patients with intracranial ependymoma and 31 with intramedullary ependymoma who underwent surgery in the last ten years were collected and correlated with the recurrence time and overall survival.

RESULTS

There was statistically significant correlation between the degree of resection and intracranial tumor location, although it is not a hallmark of recurrence. Data analyses of intramedullary ependymoma did not show correlation with overall survival and likelihood of recurrence.

CONCLUSION

The location of the intracranial tumor is connected with the degree of resection; however it is not a predictive factor to overall survival.

Survival following treatment for intracranial ependymoma: a review

The actual definition of survival rates following treatment for intracranial ependymomas is substantially influenced by the strict interaction among different factors. Age, location, and grading, for example, act together, negatively influencing the prognosis of younger children also invariably influenced by the more demanding role of surgery and the still limited use, up to recently, of radiotherapy under 3 years of age. In the same direction, the worse prognosis in most series of infratentorial ependymomas if compared with their supratentorial counterpart should be cautiously considered, midline posterior fossa tumors having completely different implications from those originating or predominantly extending to the cerebellopontine angle, where the extent of surgery has more invariably to compare with patients' quality of life. New radiotherapic regimens and their applications in infancy are promisingly demonstrating an improvement of present prognostic criteria, with the limit of still insufficient information on their long-term secondary effects. Similarly, molecular biology research studies, though still in their preclinical stage, are prompting to change the concept of a substantially chemoresistant tumor helping to stratify these lesions with the final aim of targeted pharmacological therapies. In the present review paper, we investigated singularly the role that the more commonly considered prognostic factors have had in the literature on survival of children affected by intracranial ependymomas, trying to elucidate their cumulative effect on the actual knowledge of this issue.

Surgical considerations in fourth ventricular ependymoma with the transcerebellomedullary fissure approach in focus

INTRODUCTION

Within the existing consensus for the best management of pediatric infratentorial ependymomas (PIE), surgery is the most important stage, where complete removal should be the perfect aim, before complementing it with chemo- or radiotherapy. That, however, remains a challenge even for the most skillful surgeons because of the vicinity of important brainstem and cranial nerve structures involved and is particularly difficult in lateral extensions.

MATERIALS AND METHODS

The paper analyzes the current trends of PIE treatment with emphasis on resection difficulties created by lateral extensions. Anatomical analysis and clinical application of the cerebellomedullary fissure dissection has created specific approaches, providing safe route to the lateral recess and cerebellopontine area by dividing safely tenia and tonsils and biventer lobes retraction.

DISCUSSION AND CONCLUSION

Bilateral and unilateral approaches have been developed. This approach prevents the damage of transvermian access and the resulting cerebellar mutism in some cases. Indications, technique and benefits of transcerebellomedullary fissure types of approaches are discussed.

New chemotherapy strategies and biological agents in the treatment of childhood ependymoma

INTRODUCTION

With the limited role of current treatment regimens and potential associated side effects of radiation in young children with ependymoma, considerable effort is being focused on new chemotherapeutic strategies and biologic agents.

DISCUSSION AND CONCLUSION

Identification of those molecular changes underlying the development of ependymoma may, in time, lead to the development of not only novel therapeutic agents, but also specific patient-tailored therapies directed against known cell-signaling pathways.

Advances in surgical techniques for resection of childhood cerebellopontine angle ependymomas are key to survival

BACKGROUND

Childhood cerebellopontine angle (CPA) ependymoma is an uncommon anatomical variant of posterior fossa ependymoma. In infants and young children, the tumor often goes undetected until it causes hydrocephalus. As CPA ependymomas grow, they distort the anatomy and encase cranial nerves and vessels, thereby making resection a formidable surgical challenge.

PURPOSE

The purpose of this paper is to describe the surgical technique used to achieve gross total resection (GTR) of CPA ependymomas and demonstrate improved survival in these patients.

MATERIALS AND METHODS

Surgical techniques used for GTR in 45 patients with CPA ependymoma treated from 1997 to 2008 are described. Results of those procedures are compared with data from 11 patients who previously underwent surgical resection (1985-1995).

RESULTS

We achieved GTR in 43 (95.6%) patients and near-total resection in two (4.4%); the probability of progression-free survival was 53.8%, and that of overall survival was 64%.

CONCLUSION

Our novel surgical techniques greatly improve central nervous system function and survival among pediatric patients with CPA ependymoma.

The role of stereotactic radiotherapy in the management of ependymomas

INTRODUCTION

Intracranial ependymomas in children have high rates of recurrence. Salvage therapy typically includes repeat resection, possibly chemotherapy, and re-irradiation. Stereotactic radiosurgery has been used for re-irradiation. It offers the theoretical advantages of delivering a high dose of radiation to a small target, providing a maximum dose to the tumor while avoiding surrounding critical brain structures and previously irradiated tissue.

DISCUSSION

Few reports in the literature describe this technique, with mixed, but not often successful, outcomes.

The history of ependymoma management

INTRODUCTION

The ependymomas are relatively not a common tumor. However, most clinicians agree that the radical removal of the tumor is the most important prognostic factor.

MORBIDITY OF TREATMENT

Tumor removal was not sufficient before the era of magnetic resonance imaging (MRI) and resulted in a considerable operative morbidity and mortality. As the microneurosurgical techniques and microsurgical anatomy become popular and the MRI provide more detailed anatomical information preoperatively, radical removal of this complex and complicated tumor can be more feasible. In childhood ependymoma, the treatment-related morbidity and mortality can be the special issues, which can modify the policy of management safe tumor removal and minimal adjuvant treatment, which are extremely important.

RADIATION THERAPY

Radiation treatment has been the option for disseminated disease and residual tumor. With the advancement of detailed MR anatomical information, safer and more delicate radiation becomes possible with newer radiation modalities, three-dimensional conformal radiotherapy, intensity modulating radiotherapy, and tomotherapy.

PROGNOSTIC FACTORS

Although many clinicians believe that the ependymomas are inheritably chemoresistant, the new targets for the treatment are under investigation or clinically tried. Also, the genetic alterations of ependymoma are developing and might be a promising target.

CONCLUSION

The surgical techniques and assistant modalities for tumor removal are still advancing. So, the outcome of ependymoma is still improving. Unfortunately, newer treatment modalities, such as new chemotherapeutic agent and gene modification agent, are still not promising. The history of ependymoma management is still in progress.

Pediatric ependymoma: biological perspectives

Pediatric ependymomas are enigmatic tumors that continue to present a clinical management challenge despite advances in neurosurgery, neuroimaging techniques, and radiation therapy. Difficulty in predicting tumor behavior from clinical and histological factors has shifted the focus to the molecular and cellular biology of ependymoma in order to identify new correlates of disease outcome and novel therapeutic targets. This article reviews our current understanding of pediatric ependymoma biology and includes a meta-analysis of all comparative genomic hybridization (CGH) studies done on primary ependymomas to date, examining more than 300 tumors. From this meta-analysis and a review of the literature, we show that ependymomas in children exhibit a different genomic profile to those in adults and reinforce the evidence that ependymomas from different locations within the central nervous system (CNS) are distinguishable at a genomic level. Potential biological markers of prognosis in pediatric ependymoma are assessed and the ependymoma cancer stem cell hypothesis is highlighted with respect to tumor resistance and recurrence. We also discuss the shifting paradigm for treatment modalities in ependymoma that target molecular alterations in tumor-initiating cell populations.

Intracranial ependymoma: factors affecting outcome

Ependymomas account for 2-9% of all neuroepithelial tumors, amounting to 6-12% of all intracranial tumors in children and up to 30% of those in children younger than 3 years. Recent findings provide evidence that intracranial and spinal ependymomas share similar molecular profiles with the radial glia of their corresponding locations. The management of intracranial ependymoma is still not optimal. The 5-year progression-free survival for children with ependymoma ranges between 30 and 50% with a worse prognosis for patients with residual disease after surgery. The prognostic relevance of most factors are still being debated. Recent studies, in which the current WHO classification criteria were applied, reported the relationship between histological grade and outcome. Biomolecular studies have identified that gain of 1q25 and EGFR overexpression correlate to poor prognosis, whereas low expression of nucleolin correlated with a favorable outcome. Ependymomas have been considered a 'surgical disease', where completeness of excision can be reached in approximately half of the cases. At present the standard treatment is radiation therapy for all patients after gross-total or near-total resection. For high-risk patients, with residual tumor, an interesting, although experimental, approach could be chemotherapy followed by secondary surgery and postoperative conformal irradiation.

Outcomes of malignant CNS ependymomas: an examination of 2408 cases through the Surveillance, Epidemiology, and End Results (SEER) database (1973-2005)

BACKGROUND

Determine the role of surgery and radiation therapy for patients with malignant CNS ependymomas.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database (1973-2005) was queried.

RESULTS

Overall, a total of 2408 cases of malignant ependymomas were identified. Of these, 2132 cases (88.5%) were identified as WHO grade II ependymomas and 276 cases (11.5%) as WHO grade III (anaplastic) ependymomas. The annual incidence of ependymomas was approximately 1.97 cases per million in 2005. Overall median survival for all patients was 230 mo, with a significant difference between women and men (262 mo versus196 mo, respectively) (P=0.004). Median age at diagnosis was 37 y among females and 34 y in males. Patients who successfully underwent surgical resection had a considerably longer median survival (237 mo versus 215 mo, P<0.001) as well as a significantly improved five-year survival (72.4% versus 52.6%, P<0.001). Univariate analysis demonstrated that age, gender, ethnicity, primary tumor site, WHO grade and surgical resection were significant predictors of improved survival for ependymoma patients. Multivariate analysis identified that a WHO grade III tumor, male gender, patient age, intracranial tumor locations and failure to undergo surgical resection were independent predictors of poorer outcomes. Multivariate analysis of partially resection cases revealed that lack of radiation was a sign of poor prognosis (HR 1.748, P=0.024).

CONCLUSION

Surgical extirpation of ependymomas is associated with significantly improved patient survival. For partially resected tumors, radiation therapy provides significant survival benefit.

OUTCOME PREDICTORS FOR INTRACRANIAL EPENDYMOMA RADIOSURGERY

OBJECTIVE

To develop outcome predictors after stereotactic radiosurgery (SRS) in patients with intracranial ependymomas who had received previous fractionated radiation therapy, we compared tumor control, survival, and complications with tumor grade, volume, age of patients, and imaging characteristics.

METHODS

We retrospectively reviewed records of 39 consecutive ependymoma patients who underwent SRS for 56 tumors. The median patient age was 22.8 years (range, 2.9–71.1 years). All patients had previous surgical resection of their ependymomas followed by radiotherapy, and 14 patients underwent previous chemotherapy. Twenty-five patients had low-grade ependymomas (34 tumors), and 14 patients had anaplastic ependymomas (22 tumors). The median radiosurgery target volume was 3.6 cm3 (range, 0.1–36.8 cm3), and the median margin dose was 15.0 Gy (range, 10–22 Gy).

RESULTS

At a median of 23.5 months after SRS (range, 6.1–155.2 months), 25 patients died as a result of metastases (12 patients) or disease progression (13 patients). The overall survival rates after SRS were 60.1, 36.1, and 32.1% at 1, 3, and 5 years, respectively. The progression-free survival rates after SRS at 1, 3, and 5 years were 81.6, 45.8, and 45.8%, respectively, for all grades of ependymomas. Lower histological tumor grade was not significantly associated with better progression-free survival (P = 0.725). Factors associated with an improved progression-free survival included smaller tumor volume and homogeneous tumor contrast enhancement in low-grade ependymomas.

CONCLUSION

SRS provides another management option for patients with residual or recurrent ependymomas that have failed surgery and radiation therapy. Predictors of response include smaller volume and homogeneous contrast enhancement.

Initial management of childhood brain tumors: neurosurgical considerations

Intracranial tumors are the most common solid tumors in children. The infratentorial compartment will be the primary site for 60% to 70% of these tumors, including astrocytomas, medulloblastomas, and ependymomas. Several technological advancements have increased our knowledge of the cell biology of pediatric brain tumors, facilitated earlier diagnosis, and improved neurosurgical resections while minimizing neurological deficits. These in turn have not only improved the survival of children with brain tumors but also their quality of life. Current management strategies in most cases rely on surgery coupled with adjuvant therapies, including radiation therapy and chemotherapy. The vulnerability of the immature brain to adjuvant therapies creates many challenges for the treating physician. We review current diagnostic and therapeutic approaches and outcome for children harboring the most common pediatric brain tumors: astrocytomas (low-grade and high-grade glioma), ependymoma, medulloblastoma, and craniopharyngioma. The emphasis will be on the neurosurgical management of children with these tumors.

Multifactorial analysis of predictors of outcome in pediatric intracranial ependymoma

Pediatric ependymomas are enigmatic tumors, and their clinical management remains one of the more difficult in pediatric oncology. The identification of biological correlates of outcome and therapeutic targets remains a significant challenge in this disease. We therefore analyzed a panel of potential biological markers to determine optimal prognostic markers. We constructed a tissue microarray from 97 intracranial tumors from 74 patients (WHO grade II-III) and analyzed the candidate markers nucleolin, telomerase catalytic subunit (hTERT; antibody clone 44F12), survivin, Ki-67, and members of the receptor tyrosine kinase I (RTK-I) family by immunohistochemistry. Telomerase activity was determined using the in vitro-based telomere repeat amplification protocol assay, and telomere length was measured using the telomere restriction fragment assay. Primary tumors with low versus high nucleolin protein expression had a 5-year event-free survival of 74%+/-13% and 31%+/-7%, respectively. Multivariate analysis identified low nucleolin expression to be independently associated with a more favorable prognosis (hazard ratio=6.25; 95% confidence interval, 1.6-24.2; p=0.008). Ki-67 and survivin correlated with histological grade but not with outcome. Immunohistochemical detection of the RTK-I family did not correlate with grade or outcome. Telomerase activity was evident in 19 of 22 primary tumors, with telomere lengthening and/or maintenance occurring in five of seven recurrent cases. Low nucleolin expression was the single most important biological predictor of outcome in pediatric intracranial ependymoma. Furthermore, telomerase reactivation and maintenance of telomeric repeats appear necessary for childhood ependymoma progression. These findings require corroboration in a clinical trial setting.

Intensity-modulated radiation therapy in childhood ependymoma

PURPOSE

To determine the patterns of failure after intensity-modulated radiation therapy (IMRT) for localized intracranial ependymoma.

METHODS AND MATERIALS

From 1994 to 2005, 22 children with pathologically proven, localized, intracranial ependymoma were treated with adjuvant IMRT. Of the patients, 12 (55%) had an infratentorial tumor and 14 (64%) had anaplastic histology. Five patients had a subtotal resection (STR), as evidenced by postoperative magnetic resonance imaging. The clinical target volume encompassed the tumor bed and any residual disease plus margin (median dose 54 Gy). Median follow-up for surviving patients was 39.8 months.

RESULTS

The 3-year overall survival rate was 87% +/- 9%. The 3-year local control rate was 68% +/- 12%. There were six local recurrences, all in the high-dose region of the treatment field. Median time to recurrence was 21.7 months. Of the 5 STR patients, 4 experienced recurrence and 3 died. Patients with a gross total resection had significantly better local control (p = 0.024) and overall survival (p = 0.008) than those with an STR. At last follow-up, no patient had developed visual loss, brain necrosis, myelitis, or a second malignancy.

CONCLUSIONS

Treatment with IMRT provides local control and survival rates comparable with those in historic publications using larger treatment volumes. All failures were within the high-dose region, suggesting that IMRT does not diminish local control. The degree of surgical resection was shown to be significant for local control and survival.

The prognostic value of histological grading of posterior fossa ependymomas in children: a Children's Oncology Group study and a review of prognostic factors

We performed a retrospective analysis of 96 pediatric posterior fossa ependymomas in order to determine the prognostic value of histological grade based on the current WHO grading scheme. The patients were selected among Children's Oncology Group (previously Pediatric Oncology Group-POG) patients enrolled in clinical trials, and on the basis of central pathology review, location, and age. We excluded entities such as sub-ependymoma, myxopapillary, or clear-cell ependymoma, after a consensus diagnosis by three neuropathologists. A total of 66 males and 30 females with a median age of 48 months were identified. The group was analyzed to determine the effects of histological grade, age, gender, and extent of resection on event-free and overall survival. Our results showed that extent of resection, age, and histological grade were independent prognostic variables for event-free survival. The relative risk for extent of resection and histological grade was calculated as 3.59 (P<0.001) and 3.58 (P<0.001), respectively. Overall survival significantly correlated with extent of resection and age, but not with histological grade. We compared our results with peer-reviewed publications on pediatric intracranial ependymomas in the English language between 1990 and 2005. Selection criteria identified 32 manuscripts involving 1444 patients. Extent of resection was a significant factor in 21, age in 12, and histological grading in nine of these studies. Other factors reported to be significant by more than one study included tumor location and radiation treatment. Our findings suggest that histological grade (WHO Grade II vs III) is an independent prognostic indicator for event-free survival, but may not be so for overall survival in pediatric posterior fossa ependymomas. We believe that an accurate assessment of the prognostic value of histological grade depends on the selection of a well-characterized clinical cohort of sufficient size, and the inclusion of relevant histological criteria as outlined in the WHO classification scheme.

The molecular biology of ependymomas

Intracranial ependymomas are the third most common primary brain tumor in the pediatric population. Although an anaplastic variant is recognized, numerous studies examining the prognostic implications of histological features, such as necrosis, endothelial proliferation and mitoses, have yielded contradictory results. In order to improve outcome prediction in affected patients and to refine therapeutic decision-making, there is a strong need for identifying relevant biological correlates of tumor behavior. The molecular biology of tumors is a rapidly expanding field and includes investigations into cytogenetics, oncogenes, growth factors, growth factor receptors, hormonal receptors, proliferation markers, apoptosis, cell cycle genes and cell adhesion molecules, as well as factors potentially related to therapeutic resistance, such as the multidrug resistance gene. The molecular biology of astrocytic tumors in adults has been the subject of many studies; however, relatively few studies have been focused on ependymomas. Herein we review potential oncological markers in ependymomas that have been identified to date and highlight the limitations of our current knowledge as a basis for defining areas for future investigation.

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.

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 young children newly diagnosed with ependymoma, treated with intensive induction chemotherapy followed by myeloablative chemotherapy and autologous stem cell rescue

BACKGROUND

The purpose of this study is to investigate the efficacy of an intensive chemotherapy induction regimen followed by myeloablative chemotherapy and autologous hematopoietic stem cell rescue (AHSCR) in children with newly diagnosed ependymoma.

PATIENTS AND METHODS

Twenty-nine children less than 10 years of age at diagnosis of ependymoma were enrolled on the "Head Start" studies. Twenty-four patients with localized disease received an induction regimen including five cycles of chemotherapy (cisplatin, vincristine, etoposide cyclophosphamide, and high dose methotrexate for patients with metastatic disease). Following induction, individuals without evidence of disease proceeded to marrow-ablative chemotherapy (thiotepa, carboplatin, and etoposide) with AHSCR.

RESULTS

The estimated 5-year event free survival (EFS) and overall survival (OS) from diagnosis were 12% (+/-6%) and 38% (+/-10%), respectively. The toxic mortality amongst this group of 29 patients was 10.3%. Younger age (less than 18 months at diagnosis) was the only statistically significant prognostic factor. The estimated 5-year OS rate for the five patients with metastatic disease at presentation was 80% (+/-18%). Overall, radiation-free survival at 5 years from diagnosis was 8% (+/-5%).

CONCLUSIONS

The use of an intensive induction chemotherapy regimen including myeloablative chemotherapy followed by AHSCR in newly diagnosed young children with ependymoma is not superior to other previously reported chemotherapeutic strategies.

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.

Effects of surgical resection and adjuvant therapy on pediatric intracranial ependymomas

The optimal therapy of pediatric ependymomas is controversial. The benefit of surgical resection is widely accepted, but the role of adjuvant therapy is subject to debate. Due to the relatively low survival rates of ependymoma patients, as well as the tumor's high recurrence rates, further research into the efficacy of treatment strategies and adjuvant therapy is necessary. Extent of resection remains the most important determinant of survival in patients with ependymomas. Expectantly, gross total resection yields the best outcome for patients. The optimal roles of chemotherapy and radiation therapy are poorly understood. A closer look at the efficacy of tailored radiation therapy and the possible use of chemotherapy to delay radiation therapy sheds light on potential treatment modalities for ependymomas. The greatest increase in survival on the ependymoma population will likely come from an increase in the rate of complete resections. An improvement in the efficacy of radiation therapy in addition to an understanding of chemotherapy protocols and treatment durations will hopefully provide further means for successfully treating ependymomas.

Advances in the treatment of pediatric brain tumors

Brain tumors are a heterogeneous group of neoplasms with different origins, pathobiologies, treatments and prognoses. The collective contributions from the fields of neuro-oncology, neurosurgery, radiation oncology, neurology, neuropathology, neuroradiology and molecular biology have all led to significant advances in the treatment of certain brain tumors. Ideas from these fields, under the cooperative umbrella of clinical cancer trial consortia, have been tested in large-scale studies. As a result, patient survivals have increased markedly for these tumor types. Unfortunately, there are certain brain tumors in childhood, such as the diffuse intrinsic pontine glioma and atypical teratoid rhabdoid tumor, for which survival advantages have not been found. This review will discuss the current and possible future therapies of the most common pediatric brain tumors and highlight some of the novel imaging modalities that are used pre- and intraoperatively.

The role of Gamma Knife Radiosurgery in the management of unresectable gross disease or gross residual disease after surgery in ependymoma

PURPOSE/OBJECTIVE

To evaluate the efficacy and the toxicity of Gamma Knife (GK)-based stereotactic radiosurgery (SRS) in the management of gross disease in ependymoma.

MATERIALS AND METHODS

Eight patients with 13 ependymomas were treated with GK-based SRS in our institution for gross disease. Five patients were treated for recurrent disease that developed after surgery and external beam radiotherapy (EBRT), two received SRS to the gross disease after surgery and EBRT, and one received SRS alone (in a 1.3 year old child). Median EBRT dose was 54.4 Gy (range 50-55.8 Gy). Median SRS dose was 14 Gy (range 12-20 Gy). Seven of eight (87.5%) patients had SRS to a single lesion and one of eight (12.5%) patients had treatment to six tumors in three different sessions.

RESULTS

The median follow up was 30.2 months (range 8-65.4 months). Out of the eight patients treated with SRS, six (75%) were alive, four (50%) were alive with no recurrence, two (25%) were alive with recurrence, and two (25%) died of recurrent disease. Both patients treated with SRS as a boost were alive and without recurrence. Out of the five patients who received SRS as salvage treatment, three (60%) were alive, two (40%) were alive without recurrence, two (40%) developed distant failure, and three (60%) had in-field control. Two patients who received SRS to their brainstem lesions developed symptoms related to radionecrosis and were successfully treated with steroid with good control of symptoms.

CONCLUSIONS

GK-based SRS appears to be a feasible and safe treatment modality for patients with ependymoma with unresectable gross disease or gross residual disease after surgery. SRS provides reasonable local control but out-of-field tumor progression remains an issue. For patients who receive SRS as a boost, the local control appears to be excellent.

Ependymal tumors in childhood

BACKGROUND

Ependymal tumors are classified as ependymoma (benign or low grade) versus anaplastic ependymoma (malignant or high grade). Ependymomas represent 5-10% of intracranial neoplasm in children. In this study, demographic data and the treatment results of pediatric patients with ependymal tumors, treated in a single institute, is reported.

PATIENTS AND METHODS

Between 1989 and 2001, 40 (22 M/18 F) previously untreated patients with a median age of 5.5 years (3 months-15 years), of histologically proven ependymal tumors (except ependymoblastomas) were referred to the Institute of Oncology, University of Istanbul. The localization was supratentorial in 18, infratentorial in 20, both supra and infratentorial in two patients. Histologic subgroups were 18 ependymomas (43.6%), and 22 anaplastic ependymomas (56.4%). Total tumor resection was performed in 20 patients (50%), subtotal in 18 patients (45%), and biopsy only in 2 patients (5%). Postoperative treatment consisted of regional (8 patients) or craniospinal (CSI) (9 patients) radiotherapy (RT) in patients with ependymoma; regional (7 patients) or CSI RT (14 patients) with chemotherapy (ChT) in patients with anaplastic ependymoma; ChT only (1 patient) in patients less than 3 years of age. The standard technique for posterior fossa irradiation was parallel-opposed lateral fields and total dose was 45-54 Gy. Between September 1989 and May 1991 patients received regimen A, which consisted of RT followed by eight-in-one ChT, given every 4 weeks for eight courses. Patients who were treated between June 1991 and July 1994, received regimen B, which included two courses of postoperative "VEC" (vincristine, etoposide, cisplatin) ChT, administered every 3 weeks, followed by RT applied with low dose concomitant cisplatin used as a radiosensitizer. Patients with objective response to postoperative "VEC" continued to have "VEC" after completion of RT for six more courses. From August 1994 on, patients received regimen C, consisting of RT and concomitant infusion of cisplatin followed by "VCPCU" (vincristine, cyclophosphamide, procarbazine, lomustine) administered every 4 weeks for eight courses.

RESULTS

A total of 40 patients were included in the outcome and survival data. The 5-year overall survival (OS) rate was 64.9%, and the 5-year progression-free survival rate was 50.8% for the whole series. Median time for progression or relapse was 24.3 months and there were 19 patients (43.6%) with relapse or progression. Non-metastatic patients (P = 0.0008, 5-year OS rate was 82% vs. 29%), and totally resected patients (P = 0.01, 5-year OS rate was 80% vs. 55%), and > or =3 years of age (P = 0.04, 5-year OS rate was 75% vs. 38%) had significantly better outcome.

CONCLUSIONS

The majority of complete responders were patients who had total tumor removal. Treatment failure occurred mainly within the first 2 years, and outcome was dismal for patients who relapsed or had progressive disease. The median age at diagnosis is 6 years in our patient group; younger children (less than 3 years old) have less favorable outcome. There was no significant difference in survival or progression-free survival between the two histologic subtypes.

Intracranial ependymomas in childhood: recurrence, reoperation, and outcome

INTRODUCTION

Intracranial ependymomas (IE) in children are aggressive tumors, and total resection (TR) is considered to be the most powerful predictor of outcome. The data regarding recurrent IE (RIE), in particular the role of reoperation, are scarce in the literature.

METHODS AND RESULTS

We studied 70 cases of IE in children operated on for IE since the advent of computed imaging. TR was achieved at initial surgery in 38 out of 70 cases. After a mean follow-up of 76.1 months, 33 out of 70 tumors had progressed. Eighteen were reoperated, achieving TR in 12 out of 18 cases. The morbidity associated with reoperation was minimal, especially compared with the first operation. After a mean follow-up of 74.7 months after reoperation, 10 out of 18 patients had died of tumor progression, 1 had a stable tumor, and 7 were tumor free. When TR was achieved, the overall survival rate was 7 out of 12.

CONCLUSION

Total resection is the only curative treatment for RIE and is often possible, especially when the initial resection was total.

The development of functional imaging in the diagnosis, management and understanding of childhood brain tumours

Imaging plays a fundamental role in the management of children with brain tumours. A series of new techniques, commonly grouped under the heading functional imaging, promise to give information on the properties and biological characteristics of tissues thereby adding to the structural information available from current imaging. The EPSRC funded a workshop to bring together clinicians from the UK Children's Cancer Study Group and scientific experts in the field to identify clinical problems in childhood brain tumours that may be addressed by functional imaging and to develop a clinical test bed for applying, evaluating and developing this new technology. The presentations and discussion sessions from the workshop are summarised and a review of the current 'state of the art' for this rapidly developing area provided. A key output of the workshop was agreement on a series of hypotheses which can be tested in carefully designed clinical studies.

Prognosis-related histomorphological and immunohistochemical markers in central nervous system tumors of childhood and adolescence

Brain tumors account for approximately 20% of all childhood cancers, and are the leading cause of cancer morbidity and mortality among children. Although numerous demographic, clinical and therapeutic parameters have been identified over the past few years that have significant prognostic bearing for some pediatric brain tumors, predicting the clinical course and outcome among children with central nervous system tumors is still difficult. A survey of publications on prognosis-related histopathological and immunohistochemical features among pediatric brain tumors revealed 172 series, of which 91 presented statistically significant outcome-associated parameters as defined by a P value of less than 0.05. Most investigations revealing significant prognosis-related markers were performed on medulloblastomas (30 publications), ependymomas (25) and astrocytic tumors (18). In total, 16 cohorts consisted of more than 100 cases (5 on ependymomas, 3 each on medulloblastomas and astrocytic tumors). On the other hand, there were also 13 series with fewer than 20 cases (5 on medulloblastomas). Potentially prognostic histopathological markers vary among different entities and consist of assessment of necroses, mitoses, differentiation, vascular proliferation, and growth pattern, whereas immunohistochemical features include proliferation markers (Ki-67, MIB-1), expression of oncogenes/tumor suppressor genes and their proteins (TP53, c-erbB2), growth factor and hormonal receptors (VEGF, EGFR, HER2, HER4, ErbB-2), cell cycle genes (p27, p14ARF) and cell adhesion molecules, as well as factors potentially related to therapeutic resistance (DNA topoisomerase IIalpha, metallothionein, P-glycoprotein, tenascin). This review discusses the prognostic potential of histopathological and immunohistochemical markers that can be investigated by the practicing neuropathologist as part of the routine diagnostic workload, and scrutinizes their benefit for predicting therapy response and patient outcome among children with brain tumors.

Pediatric surgical neuro-oncology: current best care practices and strategies

Significant advances have been made in the diagnosis and treatment of childhood brain tumors. Gross total surgical resection combined with appropriate adjuvant therapies can achieve a high rate of disease control for low grade gliomas, ependymomas and medulloblastomas. High grade gliomas, tumors involving the optic apparatus or diencepahalic structures, diffuse brainstem lesions, and recurrent or metastatic disease still pose considerable therapeutic challenges. We review the current treatment strategies of the three most common types of pediatric brain tumors: gliomas, medulloblastomas and ependymomas, and discuss current and future diagnostic and therapeutic modalities.

Surgical outcomes of cerebellar tumors in children

Cerebellar tumors in childhood are generally associated with a favorable outcome if they are managed appropriately. 27 cases of pediatric cerebellar tumors, operated over a 7-year period, are presented. Histopathological diagnoses were as follows: pilocytic astrocytoma (48.2%); medulloblastoma (22.2%); ependymoma (18.5%); fibrillary astrocytoma grade III (3.7%); cystic oligodendroglioma (3.7%), and hemangioblastoma (3.7%). Microscopic gross total resection was achieved in 16 (59.3%) of 27 cases. The total removal of pediatric cerebellar tumors without neurological deficit is possible with appropriate microsurgical techniques excluding brain stem invasion. The follow-up periods must be shorter if brain stem invasion exists. Radiotherapy and chemotherapy are the adjuvant therapies according to the pathological diagnosis and the patient's age.

Preliminary Results From a Phase II Trial of Conformal Radiation Therapy and Evaluation of Radiation-Related CNS Effects for Pediatric Patients With Localized Ependymoma

Purpose

We conducted a phase II trial of conformal radiation therapy (CRT) for localized childhood ependymoma to determine whether the irradiated volume could be reduced to decrease CNS-related side effects without diminishing the rate of disease control.

Patients and Methods

Between July 1997 and January 2003, 88 pediatric patients (median age, 2.85 ± 4.5 years) received CRT in which doses (59.4 Gy to 73 patients or 54.0 Gy after gross-total resection to 15 patients younger than 18 months) were administered to the gross tumor volume and a margin of 10 mm. Patients were categorized according to extent of resection (underwent gross total resection, n = 74; near-total resection, n = 6; subtotal resection, n = 8), prior chemotherapy (n = 16), tumor grade (anaplastic, n = 35), and tumor location (infratentorial, n = 68). An age-appropriate neurocognitive battery was administered before and serially after CRT.

Results

The median length of follow-up was 38.2 months (± 16.4 months); the 3-year progression-free survival estimate was 74.7% ± 5.7%. Local failure occurred in eight patients, distant failure in eight patients, and both in four patients. The cumulative incidence of local failure as a component of failure at 3 years was 14.8% ± 4.0%. Mean scores on all neurocognitive outcomes were stable and within normal limits, with more than half the cohort tested at or beyond 24 months.

Conclusion

Limited-volume irradiation achieves high rates of disease control in pediatric patients with ependymoma and results in stable neurocognitive outcomes.

Ependymal tumors

Ependymal tumors are rare malignancies that arise from the cells that line the ventricles and central canal of the spinal cord. Although they are more common in children, adults may also be effected by ependymal tumors. Prognosis is dependent on tumor location, histology, especially for myxopapillary tumors that tend to occur in the lumbar spine, extent of surgical resection, and stage of disease. Standard therapy consists of complete resection when feasible. The exact role of adjuvant radiotherapy in patients with radiographically confirmed complete resection is poorly defined. Patients with known residual disease may benefit from local radiation therapy, but the extent of radiation field and total dose are controversial. Even in patients treated with involved field radiotherapy, most relapses occur within the original tumor bed, thus local control remains the biggest obstacle to effective therapy. Chemotherapy has little impact against this tumor and has no role in the adjuvant setting, outside of a well designed clinical trial, with the possible exception of children younger than 5 years in an effort to delay radiation. A minority of patients may respond to one of several chemotherapy regimens at the time of recurrence, but the impact of this therapy is limited. Newer treatment strategies are needed.