Lack of histopathological correlation of malignant ependymomas with postoperative survival

A rare case report of pituicytoma with biphasic pattern and admixed with scattered Herring bodies

BACKGROUND

Pituicytoma is a rare pituitary non-neuroendocrine tumour. The awareness of pituitary non-neuroendocrine tumours has gradually increased over the past several decades, but the knowledge of some histological variants of the tumours is limited, particularly in clinicopathological significance. Here, we report a rare case of pituicytoma variant.

CASE PRESENTATION

A 71-year-old man presented with sudden symptoms of stroke including urinary incontinence, weakness in right lower limb, and trouble speaking. Physical examinations showed a right facial paralysis. The radiological examinations eventually found a 1.7 × 1.4 × 1.3 cm sellar occupied lesion. After symptomatic treatment improved the symptoms, the patient underwent transsphenoidal resection of the pituitary mass. Histologically, the tumour contained hypocellular area and hypercellular area. The hypocellular area showed elongated spindle cells arranged in a fascicular pattern around small vessels and scattered Herring bodies; the hypercellular area showed a large number of pseudorosettes. Immunohistochemistrically, the tumour cells were positive for thyroid transcription factor-1, S100, and neuron-specific enolase. Neurofilament only showed a little positive in the hypocellular area, and silver impregnation was only noted in a perivascular distribution. The patient had no recurrence 4 months after the surgery.

CONCLUSIONS

The rare variant of pituicytoma has a favourable prognosis. Moreover, it needs to be distinguished pituicytomas with pseudorosettes from ependymomas because of different prognosis. Lastly, Herring bodies may occasionally be seen in the pituicytoma, which could be a potential diagnostic pitfall.

Mutation profiling of anaplastic ependymoma grade III by Ion Proton next generation DNA sequencing

Background: Ependymomas are glial tumors derived from differentiated ependymal cells. In contrast to other types of brain tumors, histological grading is not a good prognostic marker for these tumors. In order to determine genomic changes in an anaplastic ependymoma, we analyzed its mutation patterns by next generation sequencing (NGS). Methods:  Tumor DNA was sequenced using an Ion PI v3 chip on Ion Proton instrument and the data were analyzed by Ion Reporter 5.6. Results: NGS analysis identified 19 variants, of which four were previously reported missense variants; c.395G>A in IDH1, c.1173A>G in PIK3CA, c.1416A>T in KDR and c.215C>G in TP53. The frequencies of the three missense mutations ( PIK3CA c.1173A>G, KDR c.1416A>T, TP53, c.215C>G) were high, suggesting that these are germline variants, whereas the IDH1 variant frequency was low (4.81%). However, based on its FATHMM score of 0.94, only the IDH1 variant is pathogenic; other variants TP53, PIK3CA and KDR had FATHMM scores of 0.22, 0.56 and 0.07, respectively. Eight synonymous mutations were found in FGFR3, PDGFRA, EGFR, RET, HRAS, FLT3, APC and SMAD4 genes. The mutation in FLT3 p.(Val592Val) was the only novel variant found. Additionally, two known intronic variants in KDR were found and intronic variants were also found in ERBB4 and PIK3CA. A known splice site mutation at an acceptor site in FLT3, a 3'-UTR variant in the CSF1R gene and a 5'_UTR variant in the SMARCB1 gene were also identified. The p-values were below 0.00001 for all variants and the average coverage for all variants was around 2000x. Conclusions: In this grade III ependymoma, one novel synonymous mutation and one deleterious missense mutation is reported. Many of the variants reported here have not been detected in ependymal tumors by NGS analysis previously and we therefore report these variants in brain tissue for the first time.

Mutation profiling of anaplastic ependymoma grade III by Ion Proton next generation DNA sequencing

Background: Ependymomas are glial tumors derived from differentiated ependymal cells. In contrast to other types of brain tumors, histological grading is not a good prognostic marker for these tumors. In order to determine genomic changes in an anaplastic ependymoma, we analyzed its mutation patterns by next generation sequencing (NGS). Methods:  Tumor DNA was sequenced using an Ion PI v3 chip on Ion Proton instrument and the data were analyzed by Ion Reporter 5.6. Results: NGS analysis identified 19 variants, of which four were previously reported missense variants; c.395G>A in IDH1, c.1173A>G in PIK3CA, c.1416A>T in KDR and c.215C>G in TP53. The frequencies of the three missense mutations ( PIK3CA c.1173A>G, KDR c.1416A>T, TP53, c.215C>G) were high, suggesting that these are germline variants, whereas the IDH1 variant frequency was low (4.81%). However, based on its FATHMM score of 0.94, only the IDH1 variant is pathogenic; other variants TP53, PIK3CA and KDR had FATHMM scores of 0.22, 0.56 and 0.07, respectively. Eight synonymous mutations were found in FGFR3, PDGFRA, EGFR, RET, HRAS, FLT3, APC and SMAD4 genes. The mutation in FLT3 p.(Val592Val) was the only novel variant found. Additionally, two known intronic variants in KDR were found and intronic variants were also found in ERBB4 and PIK3CA. A known splice site mutation at an acceptor site in FLT3, a 3'-UTR variant in the CSF1R gene and a 5'_UTR variant in the SMARCB1 gene were also identified. The p-values were below 0.00001 for all variants and the average coverage for all variants was around 2000x. Conclusions: In this grade III ependymoma, one novel synonymous mutation and one deleterious missense mutation is reported. Many of the variants reported here have not been detected in ependymal tumors by NGS analysis previously and we therefore report these variants in brain tissue for the first time.

Multifocal intradural extramedullary anaplastic ependymoma of the spine

Ependymomas are neuroectodermal tumours arising from the ependymal lining of the ventricles and central canal of the spinal cord. Intradural extramedullary (IDEM) ependymomas which are multifocal, and/or anaplastic (WHO grade III) at presentation are exceedingly rare. We present the second case of multifocal anaplastic IDEM ependymoma in the literature. A 47-year old female presented with left gluteal and thigh pain radiating to the groin associated with paraesthesiae. She had a normal neurological examination. Magnetic resonance imaging of the lumbar spine and subsequent magnetic resonance imaging (MRI) of the remaining neuroaxis demonstrated >10 lesions throughout cervical, thoracic and lumbosacral levels. There were no intracranial lesions. The patient initially underwent surgery for removal of three symptomatic lesions at S2. She recovered well. One year later she had further surgery for three progressing lesions at T5. Four of six lesions were WHO grade III. Two smaller nodules at T5 were WHO grade II. The patient had mild sensory disturbance over the right side of the trunk which resolved postoperatively. There were no long-term sequelae. The patient subsequently underwent full craniospinal irradiation using proton beam therapy. Due to their rarity, there are no guidelines for the management of multifocal IDEM ependymoma. The only previously published case of multifocal anaplastic IDEM ependymoma by Schuurmans et al. involved surgical resection and 20 cycles of whole-spine radiotherapy. Schuurmans patient unfortunately died two years post-diagnosis with progressive cranial metastases and post-radiation myelopathy. In our case, all remaining lesions are stable and she is neurologically intact at 48-month follow up.

Assessing 'second-look' tumour resectability in childhood posterior fossa ependymoma-a centralised review panel and staging tool for future studies

PURPOSE

To improve uniformity in radiological review/reporting and discussion of surgical resection status in the forthcoming SIOP Ependymoma II trial, a central review of imaging and resection status will be carried out prior to treatment stratification. We present a review of surgical decision-making from the UKCCSG/SIOP Ependymoma trial for very young children (<3 years) (Lancet Oncol 8:696-705, 2007) and propose a primary surgical staging system for residual disease that could be used for Ependymoma II.

METHODS

Imaging of 89 patients enrolled in the UKCCSG infant Ependymoma trial was independently reviewed by 3 experienced paediatric neuro-oncology surgeons. Pre- and post-op MRI imaging was available for 28 posterior fossa cases with incomplete resection. Location of residual disease, decision to offer 'second-look' surgery (prior to adjuvant therapy), perceived chance of complete resection, and risk to cranial nerves was assessed. Recommendation for second-look surgery was compared with actual second-look surgery.

RESULTS

In the actual study period, 13 patients (46 %) had further surgery at some point. The independent panel, after blinded review of the imaging, would have offered 19 patients overall (68 %) in this same cohort up-front early second-look surgery prior to definitive adjuvant therapy. We devised a 5-point staging system to introduce consistency in staging residual disease and resectability, and this is presented.

CONCLUSIONS

Based on scans alone, a surgical panel would have offered second-look surgery to 68 % of patients with residual ependymoma. The potential benefits and drawbacks of a surgical review panel and classification system will be discussed in the context of the forthcoming Ependymoma II trial.

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.

Advances in the biology and treatment of pediatric central nervous system tumors

PURPOSE OF REVIEW

Central nervous system tumors represent the most common solid tumors in children and are a leading cause of cancer-related fatalities in this age group. Here, we provide an update on insights gained through molecular profiling of the most common malignant childhood brain tumors.

RECENT FINDINGS

Genomic profiling studies of medulloblastoma, ependymoma, and diffuse intrinsic pontine glioma (diffuse midline glioma, with H3-K27M mutation), have refined, if not redefined, the diagnostic classification and therapeutic stratification of patients with these tumors. They detail the substantial genetic heterogeneity across each disease type and, importantly, link genotypic information to clinical course. The most aggressive, treatment-resistant (and also treatment-sensitive) forms within each disease entity are identified, and their potentially actionable targets.

SUMMARY

Molecularly based classification of pediatric brain tumors provides a critical framework for the more precise stratification and treatment of children with brain tumors.

A systematic review of treatment outcomes in pediatric patients with intracranial ependymomas

OBJECT

Ependymoma is the third most common primary brain tumor in children. Tumors are classified according to the WHO pathological grading system. Prior studies have shown high levels of variability in patient outcomes within and across pathological grades. The authors reviewed the results from the published literature on intracranial ependymomas in children to describe clinical outcomes as they relate to treatment modality, associated mortality, and associated progression-free survival (PFS).

METHODS

A search of English language peer-reviewed articles describing patients 18 years of age or younger with intracranial ependymomas yielded data on 182 patients. These patients had undergone treatment for ependymoma with 1 of 5 modalities: 1) gross-total resection (GTR), 2) GTR as well as external beam radiation therapy (EBRT), 3) subtotal resection (STR), 4) STR as well as EBRT, or 5) radiosurgery. Mortality and outcome data were analyzed for time to tumor progression in patients treated with 1 of these 5 treatment modalities.

RESULTS

Of these 182 patients, 69% had supratentorial ependymomas and 31% presented with infratentorial lesions. Regardless of tumor location or pathological grade, STR was associated with the highest rates of mortality. In contrast, GTR was associated with the lowest rates of mortality, the best overall survival, and the longest PFS. Children with WHO Grade II ependymomas had lower mortality rates when treated more aggressively with GTR. However, patients with WHO Grade III tumors had slightly better survival outcomes after a less aggressive surgical debulking (STR+EBRT) when compared with GTR.

CONCLUSIONS

Mortality, PFS, and overall survival vary in pediatric patients with intracranial ependymomas. Pathological classification, tumor location, and method of treatment play a role in outcomes. In this study, GTR was associated with the best overall and PFS rates. Patients with WHO Grade II tumors had better overall survival after GTR+EBRT and better PFS after GTR alone. Patients with WHO Grade III tumors had better overall survival after STR+EBRT. Patients with infratentorial tumors had improved overall survival compared with those with supratentorial tumors. Progression-free survival was best in those patients with infratentorial tumors following STR+EBRT. Consideration of all of these factors is important when counseling families on treatment options.

Spinal cord ependymomas and myxopapillary ependymomas in the first 2 decades of life: a clinicopathological and immunohistochemical characterization of 19 cases

OBJECT

Primary spinal cord ependymomas (EPNs) are rare in children, comprising classical WHO Grade II and III tumors and Grade I myxopapillary ependymomas (MEPNs). Despite their benign histology, recurrences and neural-axis dissemination have been reported in up to 33% MEPNs in the pediatric population. Treatment options beyond resection are limited, and little is known about their tumorigenesis. The purpose of this study was to explore the tumor biology and outcomes in a consecutive series of pediatric patients treated at a single institution.

METHODS

The authors performed a retrospective clinicopathological review of 19 patients at a tertiary referral children's hospital for resection of a spinal cord ependymoma. The population included 8 patients with a pathological diagnosis of MEPN and 11 patients with a pathological diagnosis of spinal EPN (10 cases were Grade II and 1 case was Grade III). The upregulation of the following genes HOXB13, NEFL, PDGFRα, EGFR, EPHB3, AQP1, and JAGGED 1 was studied by immunohistochemistry from archived paraffin-embedded tumor samples of the entire cohort to compare the expression in MEPN versus EPN.

RESULTS

Gross-total resection was achieved in 75% of patients presenting with MEPNs and in 100% of those with EPNs. The average follow-up period was 79 months for the MEPN subset and 53 months for Grade II/III EPNs. Overall survival for both subsets was 100%. However, event-free survival was only 50% for patients with MEPNs. Of note, in all cases involving MEPNs that recurred, the patients had undergone gross-total resection on initial surgery. In contrast, there were no tumor recurrences in patients with EPNs. Immunohistochemistry revealed no significant differences in protein expression between the two tumor types with the exception of EPHB3, which demonstrates a tendency to be positive in MEPNs (6 reactive tumors of 9) rather than in EPN (2 reactive tumors of 10).

CONCLUSIONS

The authors' experience shows that, following a gross-total resection, MEPNs are more likely to recur than their higher-grade counterpart, EPNs. This supports the recommendation for close long-term radiological follow-up of pediatric patients with MEPNs to monitor for recurrence, despite the tumor's low-grade histological feature. No significant difference in the protein expression of HOXB13, NEFL, PDGFRα, EGFR, EPHB3, AQP1, and JAGGED 1 was present in this selected cohort of pediatric patients.

Anaplastic ependymoma simulating glioblastoma in the cerebrum of an adult

A case of anaplastic ependymoma of the cerebral hemisphere in which the histopathological features closely simulated those of glioblastoma is reported. The patient was a 72-year-old woman with a large, well-demarcated tumor in the left temporal lobe. The tumor was totally extirpated, but recurred 18 months later, and the patient died after 4 months. The extirpated tumor was well circumscribed from the surrounding brain tissue and consisted of a sheet-like, dense proliferation of atypical, short spindle or polygonal cells. Extensive geographic necrosis with nuclear pseudopalisading was seen. Although perivascular pseudorosettes were observed in many areas, true ependymal rosettes were absent. Immunohistochemistry for glial fibrillary acidic protein and epithelial membrane antigen and ultrastructural study confirmed the ependymal nature of tumor cells. The histopathological spectrum of anaplastic ependymoma is very wide and reflects the basically dual characteristics of ependymal cells: epithelial and glial phenotypes. The present case indicates that some anaplastic ependymomas strongly express the glial phenotype and also show remarkable anaplastic cytological features, thus closely simulating glioblastoma. The diagnostic criteria for anaplastic ependymoma, and the nosological position of highly anaplastic ependymoma and its possible clinical implications, are briefly discussed.

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.

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.

Unique molecular characteristics of pediatric myxopapillary ependymoma

Myxopapillary ependymoma (MEPN) generally can be cured by gross total surgical resection and usually manifest a favorable prognosis. However, surgery is less curative in tumors that are large, multifocal or extend outside the thecal sac. Late recurrences may occur, particularly in pediatric patients. The role of adjuvant therapy is unclear in the clinical management of recurrent tumors. Clinical trial design requires a better understanding of tumor biology. Unique molecular features of MEPN were investigated by using microarray technology to compare the gene expression of five pediatric MEPN to 24 pediatric intracranial ependymoma (EPN). The upregulation of three genes of interest, homeobox B13 (HOXB13), neurofilament, light polypeptide (NEFL) and PDGFR alpha, was further studied by immunohistochemistry in a larger cohort that included adult MEPN and EPN specimens. Protein expression in MEPN was compared to subependymoma, spinal EPN, intracranial EPN and normal fetal and adult ependyma. Immunoreactivity for HOXB13, NEFL and PDGFR alpha was strongest in MEPN and virtually absent in subependymoma. Spinal and intracranial EPN generally expressed weak or focal staining. MEPN manifests unique gene and protein expression patterns compared to other EPNs. Aberrant expression of HOXB13 suggests possible recapitulation of developmental pathways in MEPN tumorigenesis. PDGFR alpha may be a potential therapeutic target in recurrent MEPN.

Pediatric brain tumors: current treatment strategies and future therapeutic approaches

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

Spinal myxopapillary ependymoma: neurological deterioration in patients treated with surgery

STUDY DESIGN

A retrospective multicenter study of series of 20 patients with myxopapillary ependymomas, which underwent surgery. OBJECTIVE.: To evaluate the postoperative outcomes of patients surgically treated for spinal myxopapillary ependymoma. Neurologic deterioration after tumor resection is discussed in terms of the tumor encapsulation. SUMMARY OF BACKGROUND DATA.: Myxopapillary ependymomas occur most commonly in the cauda equina and/or conus medullaris region. Most series published in the literature have covered postoperative tumor recurrence and role of adjuvant radiotherapy. Few contradistinctive studies in postoperative neurological deficit were reviewed from the standpoints of MRI and histopathologic findings.

METHODS

A total of 20 patients were recruited and charts, MRI, intraoperative findings, and pathologic findings were reviewed. The follow-up period ranged from 2 to 12 years (median, 72.9 months). The surgical procedures were defined as gross total removal, piecemeal total removal, and subtotal removal. Postoperative radiotherapy was given in 3 patients in whom removal had been subtotal.

RESULTS

Gross total removal was achieved in 14 patients, piecemeal gross total and subtotal removal in 3 patients each. Neurologic deterioration after surgery was seen in 5 patients, all of which were unencapsulated tumors consisting of piecemeal gross total removal in 2 patients and subtotal removal in 3 patients. Recovery of postoperative bladder dysfunction remained unchanged in 2 patients. There were no tumor recurrence and progression of the remaining tumors. Unencapsulated tumors were more frequently seen in heterogeneously enhanced tumors on MRI than in homogenously enhanced tumors with significant difference.

CONCLUSION

In the unencapsulated ependymomas, tumor separation and manipulation of the surrounding neural tissue caused neurologic injury. The heterogeneously enhanced ependymoma not only should be evaluated and treated meticulously, but also surgeons should not stick to total removal in infiltrated and adhering tumors as subtotally resected tumors with postoperative radiotherapy have not always recurred.

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.

Long term outcomes following surgical resection of myxopapillary ependymomas

Myxopapillary ependymomas, a specific tumor variant of spinal cord ependymomas, occur most commonly in the lumbosacral region. During the study period, 1,013 patients underwent surgery for spinal cord tumors. Fifty-two of the patients had a myxopapillary ependymoma. Forty-eight of these patients underwent surgery at our institutions. There were four patients who came for consultations only. Fourteen pediatric patients were diagnosed with myxopapillary ependymoma. The overall average age at which a patient was diagnosed was 31.8 years. The average age a child was diagnosed was 12.6 years. The adult mean age was 38.7 years. The clinical presentation was of a slow, indolent course, with average symptom duration of 20.8 months. Overall, the pediatric patients had a much more aggressive clinical course with a much higher rate of local recurrence and dissemination of the tumor within the neural axis (64% versus 32%). The median time to disease recurrence was 88 months for the entire group. The overall survival after 11.5 years of follow-up was 94%. The optimal management of patients harboring myxopapillary ependymomas remains somewhat controversial. Excellent outcomes may be obtained, however, with the use of aggressive surgical techniques. No clear benefit for adjunctive chemotherapy, and radiation therapy was demonstrated.

Ki67 index in intracranial ependymoma: a promising histopathological candidate biomarker

AIMS

The Ki67 tumour cell proliferation index is an independent prognostic factor in ependymoma patients. Essential prerequisites for validation of the Ki67 index as a histopathological biomarker are the reproducibility of this factor and its prognostic influence by different observers (proof of objective clinical and analytical performance). To this end, the aim was to analyse systematically inter- and intraobserver agreement and reproducibility of the prognostic impact of the Ki67 index in intracranial ependymoma.

METHODS AND RESULTS

The study cohort contained 78 cases of intracranial ependymoma. In all cases, the Ki67 index was assessed by four experienced observers (EOs) and by four inexperienced observers (IOs) using the manual hot-spot method. There was considerable agreement on Ki67 index assessment. There was higher observer agreement among EOs compared with IOs. For each observer, survival analysis showed significant association of low Ki67 index with favourable patient outcome.

CONCLUSIONS

Our data show that the Ki67 index in intracranial ependymoma is a reproducible and robust prognostic factor and can be considered a promising histopathological candidate biomarker. Attainment of biomarker status requires further translational studies in the context of prospective therapeutic trials.

February 1997--9 year old girl with hydrocephalus

A nine year old girl presented with nausea vomiting and hydrocephalus. Imaging studies demonstrated a large right thalamic mass with areas of cystic change or necrosis. Sections of resected material showed perivascular pseudorosettes, necrosis, endothelial proliferation, numerous mitoses, densely cellular areas and numerous foci with a clear-cell morphology. This case is used to illustrate the features of anaplastic ependymomas and to discuss the relationship of the histologic features to prognosis.

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.

Resection of myxopapillary ependymomas in children

OBJECT

Currently, the optimal treatment of children harboring myxopapillary ependymomas of the spinal cord remains somewhat debatable. The authors present a retrospective study in which they evaluated the records of patients in whom resection of these lesions had been performed.

METHODS

Fourteen pediatric patients who had undergone resection of a spinal cord tumor between September 1982 and July 2004 were identified from the database as having histologically classified myxopapillary ependymomas. There were 10 boys and four girls ranging in age from 7 to 18 years (mean age 12.6 years); 71% of the patients were boys. The clinical presentation of the tumor's course was slow and indolent, and the patients had a mean symptom duration of 19.6 months. Twelve patients, who underwent a total of 16 operations, were available for long-term follow-up review. Thirteen gross-total resections and three subtotal resections were performed. There were no deaths due to surgery. Postoperatively, patients initially remained at their preoperative level of function or improved. Patients who had undergone previous surgery and radiotherapy were treated more conservatively than patients who were undergoing surgery for the first time. Four children experienced significant complications following treatment.

CONCLUSIONS

As the authors demonstrate in this study, excellent outcomes may be obtained with the use of aggressive surgical techniques with the goal being that of gross-total resection. Despite the best of resections, however, the risk of recurrence remains. Therefore, periodic neuroimaging surveillance of the neuraxis and close clinical follow up are warranted throughout the patient's life. The role for adjunctive chemo- and radiotherapy remains to be defined in the management of myxopapillary ependymomas.

Ependymoma

Ependymomas are rare tumours of neuroectodermal origin classified as myxopapillary ependymoma and subependymoma (grade I), ependymoma (grade II) and anaplastic ependymoma (grade III). The more common location is infratentorial (60%). Age <40 years and extent of surgery appear related to better prognosis, while the role of other prognostic factors, such as tumour grade and tumour site are equivocal. This emphasizes the role of surgery as the standard treatment. Postoperative radiotherapy is indicated in high-grade ependymomas, and is recommended in low-grade ependymomas after subtotal or incomplete resection (confirmed by postoperative MR). Deferral of radiotherapy until recurrence may be considered on an individual basis for patients with MR confirmation of a radical resection. Recommended dose to involved fields is 45-54 Gy for low-grade (grade II) and 54-60 Gy for high-grade ependymomas (grade III). There is no proof that postoperative chemotherapy improves the outcome. At recurrence, platinum-, nitrosourea- or temozolomide-based chemotherapy can be administered, although there is no evidence of efficacy.

[Intracranial ependymomas in adult patients. Prognostic factors, place of surgery and complementary treatment]

Prognostic factors and optimal therapy for adult intracranial ependymoma are still debated. Available data has been generally collected from retrospective and heterogeneous series including pediatric and spinal cases in particular. The goal of this article is to review and discuss the prognostic factors and the various therapeutic strategies suggested in the literature in light of prognostic and decision making features delineated from a multicentric study conducted in France.

Ependymomas

Optimal management of ependymomas includes surgical resection and evaluation of the extent of central nervous system involvement using cerebrospinal fluid cytology and craniospinal contrast-enhanced MRI. In instances of measurable residual disease, reoperation should be considered because survival of patients with ependymomas is significantly improved by performance of a complete resection. In patients not considered for further surgery and with residual disease, limited-field radiotherapy is usually administered. The role of craniospinal irradiation in patients with local disease and no evidence of metastasis is controversial because most tumor recurrences are local and at the site of the primary tumor. No clear role for adjuvant chemotherapy has been demonstrated. When used, chemotherapy for ependymomas has been administered primarily to children aged younger than 3 years as adjuvant therapy and to patients with recurrent disease who are not considered surgical candidates as salvage therapy. Recurrent ependymomas are managed by reoperation of tumors that are surgically accessible, by radiotherapy if not previously administered, and by salvage chemotherapy. The role of stereotactic radiotherapy administered as radiosurgery or brachytherapy is unclear because all reports are anecdotal. Because salvage chemotherapy is not curative, no standard therapy exists, and a variety of chemotherapy agents and drug schedules have been investigated.

Chromosomal abnormalities subdivide neuroepithelial tumors into clinically relevant groups

Gliomas are the most common primary brain tumor, and are histopathologically classified according to their cell type and the degree of malignancy. However, sometimes diagnosis can be controversial,and tumors of the same entity possibly have a wide range of survival. Genetic analysis of these tumors is considered to have great importance in terms that it can provide clinically relevant classification of the tumors and compensate for the limitation of the histological classification. Previous studies using comparative genomic hybridization (CGH) demonstrated that copy number aberrations(CNAs) were frequently recognized in these tumors, and revealed that a gain on chromosomal arm 7q was the most common CNA in diffuse astrocytomas, whereas a small population of the tumor showed losses on 1p/19q which characterizes oligodendrogliomas with good responsiveness to chemotherapeutic regime using procarbazine, nitrosourea and vincristine. High grade (malignant) gliomas(i.e. anaplastic astrocytomas, anaplastic oligodendrogliomas and glioblastomas) have been reported to have a gain on 7p and losses on 9p and 10q. In case of ependymomas, frequent chromosomal aberrations in intracranial tumors were a gain on 1q and losses on 6q, and, on the other hand, a gain on chromosome 7 was recognized almost exclusively in spinal cord tumors. These data suggest that intracranial and spinal cord ependymomas are different genetic diseases and comprise different subgroups within one histological entity. In conclusion, genetic analysis of gliomas may help to classify these tumors and provide leads concerning their initiation and progression. The relationship of these aberrations to patient outcome needs to be addressed.

Current treatment of leptomeningeal metastases: systemic chemotherapy, intrathecal chemotherapy and symptom management

Treatment of leptomeningeal metastases is multifaceted and includes symptomatic therapy, intrathecal and systemic chemotherapy, and radiotherapy. As the majority of patients have widespread incurable systemic tumor, treatment is predominantly palliative; however, some patients with leukemia, lymphoma or breast cancer may have prolonged remissions and the possibility of cure.

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.

Lucien J. Rubinstein: enduring contributions to neuro-oncology

Dr. Lucien Rubinstein is best remembered for his significant contributions to the field of neuropathology, particularly in the classification of nervous system tumors. His accomplishments in basic neuro-oncology and in the formulation of diagnostic principles reflected a unique talent for synthesizing fundamental clinicopathological concepts based on skillful diagnostic investigation and a thorough understanding of neurobiology. Dr. Rubinstein was the leader in the establishment of cell cultures from central nervous system (CNS) tumors. He meticulously analyzed both light and electron microscopic features of CNS tumors, recorded his findings, and patiently drew sketches to be shared generously with his colleagues and students. As a pioneer in neuropathology, in his work Dr. Rubinstein set the foundation for many enduring concepts in neurosurgery, neuro-oncology, neurology, and basic tumor biology.

Is gross-total resection sufficient treatment for posterior fossa ependymomas?

Object. The goals of this study were to analyze outcomes in patients with posterior fossa ependymomas, determine whether gross-total resection (GTR) alone is appropriate treatment, and evaluate the role of radiation therapy.

Methods. All patients with newly diagnosed intracranial ependymomas treated at Barrow Neurological Institute between 1983 and 2002 were identified. Those with supratentorial primary lesions, subependymomas, or neuraxis dissemination were excluded. Forty-five patients met the criteria for the study. Gross-total resection was accomplished in 32 patients (71%) and subtotal resection (STR) in 13 (29%). Radiation therapy was given to 25 patients: 13 following GTR and 12 after STR. The radiation fields were craniospinal followed by a posterior fossa boost in six patients and posterior fossa or local only in the remaining patients.

With a median follow-up period of 66 months, the median duration of local control was 73.5 months with GTR alone, but has not yet been reached for patients with both GTR and radiotherapy (p = 0.020). The median duration of local control following STR and radiotherapy was 79.6 months. The 10-year actuarial local control rate was 100% for patients who underwent GTR and radiotherapy, 50% for those who underwent GTR alone, and 36% for those who underwent both STR and radiotherapy, representing significant differences between the GTR-plus-radiotherapy and GTR-alone cohorts (p = 0.018), and between the GTR-plus-radiotherapy and the STR-plus-radiotherapy group (p = 0.003). There was no significant difference in the 10-year actuarial local control rate between the GTR-alone and STR-plus-radiotherapy cohorts (p = 0.370). The 10-year overall survival was numerically superior in patients who underwent both GTR and radiotherapy: 83% compared with 67% in those who underwent GTR alone and 43% in those who underwent both STR and radiotherapy. These differences did not achieve statistical significance. Univariate analyses revealed that radiotherapy, tumor grade, and extent of resection were significant predictors of local control.

Conclusions. Gross-total resection should be the intent of surgery when it can be accomplished with an acceptable degree of morbidity. Even after GTR has been confirmed with postoperative imaging, however, adjuvant radiotherapy significantly improves local control. The authors currently recommend the use of postoperative radiotherapy, regardless of whether the resection is gross total or subtotal.

Supratentorial malignant ependymoma in childhood: 16 years without relapse after hemispherectomy

INTRODUCTION

Malignant intracranial ependymomas in childhood have a poor prognosis, supratentorial ependymomas have the poorest clinical course with a survival rate after 5 years of 45%. The most important prognostic factor in these cases is a radical operation, which cannot usually, however, prevent relapse.

CASE REPORT

We demonstrate the case of a large malignant ependymoma of the left cerebral hemisphere in a child who has so far lived for 16 years without relapse after an extensive but uncomplicated left-sided hemispherectomy. The patient has also shown an improvement in her preoperative neurologic deficits. Her epilepsy, which was difficult to manage preoperatively, has been completely eliminated. She went to a special school for handicapped children and now works there. She does not need any help in handling everyday activities.

CONCLUSION

This case shows the significance of complete tumor resection in malignant ependymomas, which may, under certain circumstances, lead to lasting tumor control.

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.

Imaging Predictors of Intracranial Ependymomas

OBJECTIVE

To identify significant imaging prognostic factors for intracranial ependymomas.

METHODS

This series includes 32 patients (18 male and 14 female), with an age at surgery ranging from 1 to 69 years (median, 20.5 years). The preoperative images and medical records were reviewed. The following imaging predictors, including tumor size, consistency, signal character, enhanced pattern, calcification, hemorrhage, perifocal edema, and tumor spread, were analyzed by 2 radiologists independently. Overall survival and progression-free survival were calculated by the Kaplan and Meier method. The difference in these imaging predictors in terms of overall survival and progression-free survival was tested for statistical significance by the log-rank test. Multivariate analysis was also performed using the Cox proportional hazard model.

RESULTS

The results revealed that the presence of tumor spread on preoperative images was the only significant imaging predictor in overall and progression-free survivals (P < 0.0001). The hazard ratio of progression-free survival in the presence of tumor spread on preoperative images was 18.59 (95% confidence interval: 1.57-220.13; P = 0.020).

CONCLUSION

The presence of tumor spread on preoperative images is the only significant imaging predictor for patients with intracranial ependymomas.

Intraventricular gliomas

Gliomas are the most common primary brain tumor in adults, and those within or relating to the ventricular surface represent a less common but important subcategory. The most common intraventricular gliomas include ependymomas, SEs, and SEGAs. Other less common varieties have been reported, including chordoid gliomas, glioblastoma multiforme, and mixed glial-neuronal tumors. Each type of intraventricular glioma is associated with its own unique constellation of epidemiologic, clinical, radiologic, and pathologic defining characteristics. Each tumor type has its own management considerations and nuances with unique prognostic indicators and outcomes. The outcome for certain intraventricular gliomas (especially ependymomas) remains relatively poor. Future advancements in surgical technique are likely to have only a modest impact on improvement of outcome. Translational research aiming to advance the knowledge of tumor biology into new targeted cellular and molecular therapies holds tremendous promise to improve the overall outcome. Additionally, more thorough delineation of prognostic factors as well as modifications and refinements to radiation and chemotherapy may help to improve the still significantly poor outcomes for patients harboring these lesions. Future cooperative intra- and interinstitutional efforts between scientists and clinicians will hopefully culminate in an improved outlook and eventual cure for patients with gliomas.

Neurosurgical treatment of brain tumors in children

Primary brain tumors are the most common solid neoplasms of childhood. The diagnosis of brain tumors in the general pediatric population remains challenging. Nevertheless, it is clear that refinements in imaging, surgical technique, and adjunctive therapies have led to longer survival and an improving quality of life in children with brain tumors.

9p21 and 13q14 dosages in ependymomas. A clinicopathologic study of 101 cases

Ependymomas are glial neoplasms whose clinical behavior is difficult to predict based on histology alone. Recently, a comparative genomic hybridization study identified frequent chromosome 9p and 13q losses in anaplastic ependymomas, suggesting that p16 and RB alterations may be involved in tumor progression. In order to test this hypothesis further, 101 myxopapillary, conventional, and anaplastic ependymomas (51 spinal and 50 intracranial tumors) were tested for RB and p16 deletions using fluorescence in situ hybridization. Clinical follow-up, ranging from 2 to 198 months (median 46 months), was obtained in 90 cases (91%). RB and p16 deletions were seen in 22 of 92 (24%) and 22 of 89 (25%) informative cases, respectively. Polysomies were more frequent in the grade I and II spinal tumors, consistent with prior reports of increased aneuploidy in such cases. No significant genetic associations were seen with tumor grade, recurrence, or death, suggesting that 9p and 13q deletions do not play a prominent role in the malignant progression of ependymomas, as has been implicated in other glioma subtypes.

Highly anaplastic extraventricular ependymoma arising in an adult, mimicking metastatic adenocarcinoma with heavy stromal inflammation and emperiporesis

We report a case of extraventricular ependymoma arising in a 50-year-old woman that took an aggressive clinical course with recurrence three times. The initial tumor was a well-circumscribed nodule in the right temporal white matter measuring 2 cm in diameter. It showed variegated histological findings mimicking metastatic adenocarcinoma: an epithelioid arrangement of highly pleomorphic cells with pseudopapillary structures and perivascular pseudorosettes, and bizarre multinucleated giant cells with occasional emperiporesis surrounded by abundant mononuclear inflammatory cells, as well as a focal small area of conventional ependymoma. Emperiporesis and abundant mononuclear cell infiltration were not previously described in an ependymoma. The recurrent tumors predominantly showed an epithelioid pattern with frequent formation of astroblastoma-like pseudopapillary structures. Neoplastic cells were markedly atypical and had characteristic intracytoplasmic eosinophilic inclusion bodies. Much of the cells in both the initial and recurrent tumors showed a positive immunostaining for glial fibrillary acidic protein (GFAP) with accentuation to the cytoplasmic processes of the pseudorosettes and pseudopapillary structures. Epithelial membrane antigen (EMA) highlighted the epithelial differentiation of the tumor cells, while cytokeratin was completely negative. Although this tumor might be classified to at least WHO grade III from the histology and aggressive behavior, the exact grading is still controversial because of the rarity of such cases.

Ependymomas

Ependymomas are uncommon neoplasms of the central nervous system (CNS), and as a consequence, few randomized, clinical trials have been performed, thereby limiting treatment guidelines. A review of the literature would permit the following conclusions regarding treatment. The best management of newly diagnosed ependymoma entails a complete resection corroborated by postoperative contrast-enhanced magnetic resonance imaging (MRI). If an incomplete resection is documented, a second attempt at gross total resection should be considered, given the prognostic significance of complete resection. Small volume residual disease is best managed with involved-field radiotherapy unless postoperative staging (cerebrospinal fluid cytology, neuraxis MRI) documents metastatic disease, which is best managed by craniospinal irradiation. The role of chemotherapy is uncertain and in general would be reserved for patients having previously failed surgery and radiotherapy. Disease-free survival following recurrence is unusual (<15% at 5 years) and suggests intensification of initial adjuvant treatment may best prevent relapse.

Systemic chemotherapy, intrathecal chemotherapy, and symptom management in the treatment of leptomeningeal metastasis

Metastasis to the leptomeninges occurs in many common cancers, including leukemia; lung, breast, and gastrointestinal cancers; and tumors of the brain. By way of the flow of cerebrospinal fluid, leptomeningeal metastasis spreads throughout the neuraxis. Consequently, therapy for leptomeningeal metastasis must be directed to the entire central nervous system (CNS). Treatment often consists of involved-field radiotherapy, systemic chemotherapy, and intrathecal chemotherapy. However, because meningeal spread occurs most often in advanced disease, treatment is mainly palliative, except in childhood leukemia, where durable remission has been reported. This article outlines the role of systemic and intrathecal chemotherapy in patients with leptomeningeal metastases. Strategies for symptom management in these patients are also described.

Intracranial ependymomas in adult patients: analyses of prognostic factors

OBJECTIVE

The goal of our study is to identify significant prognostic factors for a series of intracranial ependymomas in an adult population. Age, location, histology, preoperative clinical status, extent of resection and radiotherapy were examined.

METHODS

Our series includes 34 patients. Ten tumors were located in the brain parenchyma, 5 in the lateral ventricle, 8 in the third and 11 in the fourth ventricle. Seventeen ependymomas were grades 2 and 17 were anaplastic. Surgical resection was gross-total in 27 patients and partial in 7.

RESULTS

At a mean follow-up of 9 years (+/- 1 year) 16 patients died and, among the 18 survivors 14 are in complete remission and 4 present a local recurrence. The 5- and 10-year overall survival rates were respectively 62% and 43%. The 5- and 10-year progression-free survivals were 47% and 43%. Univariate analysis revealed that location in the brain parenchyma and anaplasia are the only statistically significant predictors of poor outcome.

CONCLUSION

We can make out three groups of patients from our series: the first encompasses patients operated on for an intraparenchymal tumor, in all our cases an anaplastic ependymoma, with a 5-year rate of tumor-related deaths of 100%. The second group includes fourth ventricle ependymomas, which are mostly grade 2 tumors. They display a 10-year survival rate of 90%. Last group entails lateral and third ventricle ependymomas, of both low and high grade, with a 10-year survival rate of 60% for lateral ventricle and 35% for third ventricle tumors.

Current management and prognostic factors for adult ependymoma

The optimum therapeutic management in adult ependymoma remains undefined because of the low incidence of this disease and because most of reported series mainly refers to childhood, are retrospective, include a small number of patients and span several decades. The purpose of this article is to analyze, discuss and summarize the current available information regarding the therapeutic approach and the prognostic factors and to provide recommendations for ordinary clinical practice. Some important therapeutic issues like the irradiation dose and volume are also analyzed. Finally, the main open questions as well as current and expected investigation trends are discussed.

Ependymoma in childhood: prognostic factors, extent of surgery, and adjuvant therapy

OBJECT

The aim of this study was to investigate the effect of patient-related factors, extent of surgery, and adjuvant therapy on survival in children presenting with intracranial ependymoma.

METHODS

Between 1980 and 1999, 83 children (mean age 36 months) underwent surgery for intracranial ependymomas. Complete resection, verified on postoperative computerized tomography scans, was achieved in 73%. Adjuvant therapy modalities have changed over the years: before 1990 all patients received radiotherapy, whereas after 1990 the children younger than 3 years of age and later those younger than 5 years of age were treated first with chemotherapy and received radiotherapy only after their first tumor recurrence. The follow-up period averaged 70 +/- 49 months.

CONCLUSIONS

Overall survival, intraoperative deaths excluded, was 73 +/- 11% and 51 +/- 14% at 5 and 10 years, respectively. The event-free survival rate at 5 and 10 years was 48 +/- 12% and 46 +/- 12%, respectively. Most of the events were local recurrences. Despite multiple reinterventions, the overall survival rate in this group dropped to 14%. On univariate analysis, the only significant prognostic factors were complete resection and radiotherapy. Both of these factors combined increased the 5- and 10-year survival rates to 93 and 75%, respectively. Age of the patients was not a statistically independent prognostic factor. The patients in the chemotherapy group did not fare as well as those in the radiotherapy group. A subgroup (36%) within the chemotherapy group, however, survived tumor free after a mean follow-up period of 67 months. It is not clear whether this subgroup either responded well to chemotherapy or needed no adjuvant therapy. Further research is warranted to answer this question.

Immunohistochemical markers for prognosis of ependymal neoplasms

Intracranial ependymomas are the third most common primary brain tumor in children. Although clinical and histological criteria for ependymoma prognosis are recognized, studies have reported contradictory results. Prognostic significance based on immunohistochemistry of ependymomas has been reported in a few studies. One-hundred and twelve patients with intracranial ependymomas were examined retrospectively for immunoexpression of various tumor-associated antigens and apoptosis. The results demonstrated significant preponderance of expression of the tenascin, vascular endothelial growth factor protein (VEGF), epidermal growth factor (EGFR) and p53 protein in high-grade tumors. Also high-grade ependymomas revealed more prominent labeling indices (LI) for proliferative marker Ki-S1 and apoptotic index (AI), and lower LI for cyclin-dependent kinase inhibitors p27/Kipl and pl4ARF. For low-grade ependymomas the progression-free survival time (PFS) was found to be significantly shorter for Ki-S1 LI > 5%, and for tenascin, VEGF and EGFR positivity. For high-grade ependymomas PFS was found to be significantly reduced for p27 LI < 20%, p14ARF LI < 10%, for p53 positivity, and for AI < 1%. The CART modeling process exhibited five final groups of ependymoma patients (1) low-grade and tenascin-negative; (2) low-grade and tenascin-positive; (3) high-grade and p53-negative with p14 LI > 0%; (4) high-grade with combination of either p53 positivity and p14 LI > 10% or p53 negativity and p14 LI < 10%; (5) high-grade and p53-positive with pl4 LI < 10%. In summary, some immunohistochemical variables were found to be the strong predictors of ependymoma recurrence and they seem to be useful for assessing individual tumor prognosis in routinely processed biopsy specimens together with tumor grade. For histologically benign ependymomas immunohistochemical study should be focused on Ki-S1, tenascin, EGFR and VEGF evaluation, whereas p53 expression and number of p27, p14 and ISEL-positive nuclei will be of value in determining PFS from high-grade ependymomas.

Influence of tumor grade on time to progression after irradiation for localized ependymoma in children

PURPOSE

To investigate the influence of histologic grade on progression-free survival (PFS) after irradiation (RT) for pediatric patients with localized ependymoma.

METHODS AND MATERIALS

Fifty patients with localized ependymoma (median age 3.6 years, range 1-18 years at the time of RT) were treated with RT between December 1982 and June 1999. Anaplastic features were identified in 14 of 50 patients. The extent of resection was characterized as gross-total in 36 patients, near-total in 5, and subtotal in 9. The median dose to the primary site was 54 Gy. Of the 50 patients, 23 received pre-RT chemotherapy.

RESULTS

Thirty-nine patients were alive at a median follow-up of 46 months (range 21-214) from diagnosis. Thirty-four patients remained progression free at a median follow-up of 35 months (range 13-183) after the initiation of RT. Progression occurred in 16 patients (12 local and 4 local and distant), with a median time to failure of 21.2 months (range 4.6-65.0). The tumor grade significantly influenced the PFS after RT (p < 0.0005). The estimated 3-year PFS rate was 28% +/- 14% for patients with anaplastic ependymoma compared with 84% +/- 8% for patients with differentiated ependymoma. These results remained significant when corrected for age at diagnosis (<3 years), pre-RT chemotherapy, and extent of resection. Patients who received pre-RT chemotherapy had an inferior 3-year PFS estimate after RT (49 +/- 12%) compared with those who did not (84% +/- 10%; p = 0.056). Anaplastic ependymoma was found more frequently in the supratentorial brain (p = 0.002). Six of 12 patients with supratentorial tumor developed recurrence; recurrence was restricted to patients with anaplastic ependymoma.

CONCLUSION

Tumor grade influences outcome for patients with ependymoma independent of other factors and should be considered in the design and analysis of prospective trials involving pediatric patients treated with RT. Chemotherapy before RT influences the PFS and overall survival after RT. The effect is more pronounced when progression occurs during chemotherapy.