Brain tumors in children

Health-related quality of life in survivors of tumours of the central nervous system in childhood--a preference-based approach to measurement in a cross-sectional study

There is an evident need to measure the comprehensive burden of morbidity experienced by survivors of brain tumours in childhood. To this end, a questionnaire based on the Health Utilities Index mark 2 (HUI2) and mark 3 (HUI3) systems was completed independently for a cohort of such children by their parents, by a nurse, by physicians and by a selected group of the children themselves. Each of the HUI2 and HUI3 systems consists of a multi-attribute health status classification scheme linked to a preference function which provides utility scores for levels within single attributes (domains of health) and for global health states. All eligible families (n = 44) participated. Even cognitively impaired children of at least 9.5 years of age could complete the questionnaire. The greatest burden of morbidity, occurring in two-thirds of children, was in the attribute of cognition. Surprisingly, almost one-third of children experienced pain. Global health status was lowest in children who underwent radiotherapy before the age of 5 years and the corresponding utility scores were related inversely to the volume irradiated. Children with demonstrable disease had lower scores than those in whom disease was not evident. There was a high level of agreement (intraclass correlation coefficients > 0.5) on formal assessment of inter-rater reliability for global health-related quality of life utility scores. The usefulness of measures of health status and health-related quality of life, in children surviving brain tumours, has been demonstrated by this study.

Urokinase induces receptor mediated brain tumor cell migration and invasion

The plasminogen activation (PA) system plays an important role in tumor invasion by initiating pericellular proteolysis of the extracellular matrix (ECM) and inducing cell migration. Malignant brain tumors overexpress PA members and characteristically invade by migrating on ECM-producing white matter tracts and blood vessel walls. To determine whether urokinase-type plasminogen activator (uPA) and its receptor (uPAR) directly modulate the migration of brain tumor cells, we examined six human brain tumor cell lines, 2 astrocytomas (SW1088, SW1783), 2 medullobastomas (Daoy, D341Med), and 2 glioblastomas (U87MG, U118MG), for their surface uPAR expression, endogenous PA activity, and functional proteolytic activity by an ECM-degradation assay. Migration on Transwell membranes and invasion of Matrigel was then tested by pre-incubating the cells with increasing concentrations of either uPA, the proteolytically inactive amino-terminal fragment (ATF) of uPA, or the uPAR cleaving enzyme, phosphatidylinositol-specific phospholipase C (PI-PLC). All of the cell lines, except D341Med, express surface uPAR protein and uPA activity. High levels of uPAR and uPA activity correlated with cellular degradation of ECM, cell migration, and Matrigel invasion. Cell migration and invasion were enhanced by uPA or ATF in a dose dependent manner, while PI-PLC treatment abolished the uPA effect and inhibited migration and invasion. We conclude that ligation of uPAR by uPA directly induces brain tumor cell migration, independent of uPA-mediated proteolysis; and in concert with ECM degradation, markedly enhances invasion. Conversely, removing membrane bound uPAR from the surface of the cells studied inhibited their ability to migrate and invade even in the presence of proteolytically active uPA.

Application of signal transduction inhibition as a therapeutic strategy for central nervous system tumors

During the last decade, rapid progress has been made in understanding the molecular pathways underlying the proliferation of both normal and neoplastic cells. The processes by which messages to initiate protein synthesis, cell cycle progression, and even cell death are transmitted from the cell surface or the cytoplasm to the nucleus are broadly referred to as 'signal transduction'. These multistep pathways involve a host of proteins that interact with other proteins in overlapping cascades that flow downstream in a stepwise fashion from the cell membrane to the nucleus. Inappropriate overactivation or underactivation of various components of such signaling pathways can contribute to pathological processes, such as neoplasia. Conversely, molecular and pharmacological interventions that target and attempt to reverse the aberrant state of activation can potentially be of therapeutic benefit. The present article provides a background for understanding the contribution of signal transduction pathways to the proliferation of normal and neoplastic cells and describes ways in which targetted inhibition of selected signaling pathway components has been exploited to inhibit tumor growth in vitro and in vivo. Because most studies to date involving central nervous system (CNS) tumors have focused on gliomas, in view of their frequency in both the pediatric and adult age groups, the discussion of therapeutic applications for CNS neoplasia will deal primarily with these lesions. However, the basic concepts presented are generalizable to most tumor types and have been successfully applied in vitro in medulloblastomas as well. Ultimately, the translation of such strategies to the treatment of patients with malignant brain tumors may provide novel approaches for improving the poor outlook associated with these neoplasms.

Histological parameters as predictors of prognosis in childhood brain tumors

Using histological parameters with high recognition reliability, we retrospectively analyzed all newly diagnosed patients under the age of 16 years (n = 100) with brain and spinal cord tumors presenting to the National Neuroscience Centres of the Richmond and Beaumont Hospitals, Dublin, Ireland, between 1985 and 1990, allowing analysis of 5-year survival in all cases. Tumor histology was reviewed by two neuropathologists blinded to previous histological diagnosis and to the site of lesion. We found that certain histological features such as very low cell density and microcyst formation had a positive effect on prognosis. Mitoses and pleomorphism had a negative effect on prognosis, whereas necrosis and meningeal involvement had no effect on prognosis. It is suggested that identification of reliably recognized histological features rather than assignation of tumors to particular diagnostic categories may be a more reliable predictor of tumor behavior in the pediatric age-group.

Pediatric brain tumors

Brain tumors are the most common solid neoplasms in childhood. This article reviews the current classification, clinical presentations, diagnostic procedures, and principles of treatment of pediatric brain tumors. The specific presentation, treatment, and prognosis of the most common, individual types of pediatric brain tumors are discussed.

Chordoid meningioma in a child. Case report

A case of chordoid meningioma occurring in a 15-year-old girl is presented. The patient manifested seizures as the initial symptom and subsequently exhibited subclinical microcytic hypochromic anemia. The tumor, located in the falcotentorial region and associated with diffuse edema, was totally resected. On histological examination of the surgical specimen, the clustering pattern of partly vacuolated cells in the mucoid stroma mimicked chordoma; however, positive staining of individual cells for vimentin and epithelial membrane antigen led to a diagnosis of meningioma. Interestingly, the tumor cells were surrounded by a periodic acid-Schiff- and type IV collagen-positive substance. Electron microscopy demonstrated a strikingly dense and thick basal lamina. The patient's microcytic hypochromic anemia disappeared after the tumor was removed. Both the clinical and pathological features of this case resemble those of chordoid meningioma, a rare meningioma variant.

The role of protein kinase C (PKC) in the evolution and proliferation of malignant gliomas, and the application of PKC inhibition as a novel approach to anti-glioma therapy

The present article reviews the role of the second messenger enzyme protein kinase C (PKC) in the growth regulation of high-grade gliomas, and evaluates the efficacy of therapeutic strategies directed against PKC for blocking the proliferation of these malignancies in in vitro and in vivo models. The translation of such strategies to the treatment of patients with malignant gliomas may provide a novel approach for improving the otherwise grim outlook associated with these neoplasms.

CNS tumours in south-western Finland: high location, high incidence

The Department of Paediatrics at the University Central Hospital of Turku, Finland has 130,000 children under 17 y of age within its catchment area. We collected all 103 cases of newly diagnosed CNS tumours from the 15-y period of 1981-95. The incidence was 5.3:100,000, a figure twofold those usually presented. During the period 1981-85 the incidence was lower (4) than during the subsequent 5-y periods (5.7 and 6.2). There were no statistical differences between the incidences of the supra- vs infratentorial brain tumours. Optic glioma was unusually common (17%, CI 13.9-20%).

The Pediatric Risk of Mortality III--Acute Physiology Score (PRISM III-APS): a method of assessing physiologic instability for pediatric intensive care unit patients

OBJECTIVE

To develop a physiology-based measure of physiologic instability for use in pediatric patients that has an expanded scale compared with the Pediatric Risk of Mortality (PRISM) III score.

STUDY DESIGN

Data were collected from consecutive admissions to 32 pediatric ICUs (11,165 admission, 543 deaths). Patient-level data included physiologic data, outcomes, descriptive information, and diagnoses. Physiologic data included the most abnormal values in the first 24 hours of pediatric ICU stay from 27 variables. Initially, ranges of each physiologic variable were evaluated for their association with mortality. A multi-variate logistic regression analysis was used to determine the final variables and their ranges. Integer scores reflecting the relative contribution to mortality risk were assigned to the variable ranges.

RESULTS

A total of 59 ranges of 21 physiologic variables were selected. This score is called the Pediatric Risk of Mortality III--Acute Physiology Score (PRISM III-APS). Mortality increased as the PRISM III-APS score increased. Most patients have PRISM III-APS scores less than 10, and these patients have a mortality risk of less than 1%. At the other extreme, the mortality rate of the 137 patients with a PRISM III-APS score of greater than 80 was greater than 97%.

CONCLUSION

The PRISM III-APS score is an expanded measure of physiologic instability that has been validated against mortality. Compared with PRISM III, PRISM III-APS should be more sensitive to small changes in physiologic status.

Posterior fossa syndrome

Transient mutism is a well-recognized sequela of posterior fossa tumor resection in children. A recent review from our institution indicated that 12 of 142 children undergoing such procedures (8.5%) exhibited transient speech impairment, the largest series of such patients reported to date. Each child had a vermian neoplasm that was approached by division of the inferior vermis (n = 10) and/or superior vermis (n = 3). Seven children had medulloblastomas, three had astrocytomas, and two had ependymomas. None of the affected children had cerebellar hemispheric lesions; in contrast, the incidence among children with vermian neoplasms was 13%. In general, mutism developed 1 to 4 days postoperatively and typically was associated with puzzling neurobehavioral abnormalities. All children had bizarre personality changes, emotional lability, and/or decreased initiation of voluntary movements; nine exhibited poor oral intake; and five had urinary retention. Detailed neuropsychological testing was performed in seven children and confirmed the presence of widespread impairments not only in speech, but also in initiation of other motor activities. These deficits generally resolved during a period of several weeks to months, although two children had residual impairment. Characteristically, affect and oral intake normalized before the speech began to improve. These deficits were noted to correlate with the presence of edema within the brachium pontis bilaterally, although this association was not absolute. The latter observation suggests that there was not a single locus underlying this disorder, but rather that the involved neural pathways may have been impaired at any one of a number of sites within the posterior fossa. Based on the results in our patients and in others described in the literature, we postulate an important role for the cerebellum and/or its afferent and efferent connections in initiating (rather than merely coordinating) speech and other complex motor activities and a potential role for these structures in influencing overall behavior and affective state.

Comitant esodeviation resulting from neurologic insult in children

PURPOSE

Our purpose was to establish whether comitance was a common or uncommon finding in children with esodeviation associated with a neurologic insult.

METHODS

A retrospective chart review was performed of children with acquired esodeviation associated with an identifiable neurologic insult.

RESULTS

Examinations of 30 children seen over a 2-year period were analyzed. Twenty-two (73%) had brain tumors. Twelve (40%) had comitant esodeviation, and the other 18 (60%) had incomitant measurements. Of the patients with comitant esodeviation, 6 had normal abduction OU (two after recovery from bilateral sixth nerve palsies), and 6 had mild or minimal abduction deficits. Moderate or severe abduction deficits were associated with incomitant measurements.

CONCLUSIONS

Comitant esodeviation can be common in children with identifiable neurologic insults.

Microscopic local leptomeningeal invasion at diagnosis of medulloblastoma

PURPOSE

To document the incidence and outcome of patients with microscopic local leptomeningeal invasion at presentation, children with medulloblastoma were reviewed.

METHODS AND MATERIALS

Nineteen patients (1-12 years of age), who had surgical resection (14 total, 5 subtotal) and were diagnosed as medulloblastoma, were evaluated for disease extent by pre- and postoperative computerized tomography/magnetic resonance imaging, histopathologic evaluation of leptomeninges adjacent to the resected tumor tissue, myelography/magnetic resonance of the entire spine, and analysis of cerebrospinal fluid cytology. Patients were also reviewed for disease outcome.

RESULTS

Staging revealed one T2, nine T3a, eight T3b, and one T4 disease. There were 10 M0, 2 M1, 2 M2, 2 M3, and 3 Mx patients according to Chang's classification. Ten out of 19 patients (52.6%) demonstrated microscopic local leptomeningeal invasion. When only the 10 patients with M0 disease were considered, three out of five patients with microscopic local leptomeningeal invasion was found to have one or more relapses. The five other M0 patients without microscopic local invasion were in complete remission at the time of analysis.

CONCLUSION

The incidence of microscopic local leptomeningeal invasion in patients with medulloblastoma is high. Whereas the impact on survival remains to be determined in larger series, data suggests prognostic role for isolated microscopic local leptomeningeal invasion, thus validity for inclusion in the future staging system.

Brain tumors. Challenges and directions

Brain tumors account for 20% of childhood cancers and provide a "frontier" in which improved disease control and functional outcome require coordinated, directed studies in neurosurgery, radiation therapy, and chemotherapy. Among the several brain tumor types common in children, the recent experiences in medulloblastoma, ependymoma, and tumors occurring in infants and very young children are reviewed in the context of recent clinical trials and ongoing investigations.

Childhood cancer incidence in Zaragoza and Navarre (Spain): 1973-1987

Patterns and trends in childhood cancer incidence for Navarre and Zaragoza registries were studied over the 15-year period, 1973-1987. Overall cancer rates and rates for 10 specific types of cancer were analysed using a log-linear Poisson model or, alternatively, a gamma-Poisson model whenever overdispersion was present, with age, sex, registry and period being used as predictor variables. Childhood cancer was 30% more frequent in boys than in girls, and, except for lymphomas and bone tumours, incidence decreased remarkably with age. Adjusted rates were high in comparison with other European countries, particularly in the case of non-Hodgkin's lymphomas. Cancer rates proved somewhat higher in Navarre, but this difference attained statistical significance solely in the case of central nervous system tumours (rate ratio = 1.75; 95% confidence interval 1.21-2.54). A significant rise in overall incidence was observed (11% 5-yearly increase) due mainly to the upward trend in central nervous system tumours. While the rise in these tumours coincides with the period which witnessed the spread of computerised tomography in Spain, the trend nevertheless held steady over the last 5-year period, when access to this diagnostic technique had already become generalised nationwide.

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.

Exophytic brain tumors mimicking primary lesions of the cerebellopontine angle

The vast majority of cerebellopontine angle (CPA) tumors are extraaxial masses arising from either the eighth nerve (acoustic neuroma) or meninges (meningioma). Rarely, a tumor that arises from the brain parenchyma may protrude laterally to present with a clinical and radiographic picture simulating that of the much more common extraaxial lesions. Three individuals with CPA lesions that ultimately proved at operation to be exophytic brain tumors (pontine medulloblastoma, cerebellar astrocytoma, and fourth ventricular ependymoma) are described. The clinical manifestations of these lesions, although not entirely typical, fell well within the possible range of presentation of benign tumors primary to the CPA. In two of these cases the tumor actually penetrated into the internal auditory canal. As the optimal management strategy for treating parenchymal tumors differs substantially from that for extraaxial lesions, it is essential that the surgeon have a preoperative awareness of the lesion's nature before embarking on a surgical endeavor. Critical to arriving at the correct diagnosis is the close examination of preoperative imaging studies. The clinician should be alerted to the possibility that a CPA tumor is of intraaxial origin when the preoperative magnetic resonance imaging scan shows 1) blurring of the margin between the tumor and brainstem or cerebellum; 2) a degree of peritumoral hyperintensity on T2-weighted scans disproportionate to the size of the extraaxial mass; and 3) dilation of the lateral recess of the fourth ventricle.

Visual pathway glioma: an erratic tumour with therapeutic dilemmas

OBJECTIVE

Our experience in children with visual pathway glioma (VPG) was reviewed to delineate its clinical characteristics.

DESIGN

The charts and imaging studies of 21 children with VPG who were followed up in our centre during the last 12 years were reviewed and summarised.

RESULTS

VPG accounted for 13.1% of all brain tumours treated during this period. Sixty two per cent of the children with VPG had neurofibromatosis type 1 (NF-1). Among these, more than 60% were detected as part of routine work up. In some cases decreasing visual function preceded the appearance of the VPG on imaging studies. Tumour growth rate was markedly unpredictable. All treatment modalities employed led to tumour shrinkage and stabilisation for a variable period, but none was successful in totally eradicating the tumour. Complications were less severe after chemotherapy compared with radiotherapy. Three children died, none with NF-1, with a globular hypothalamic/chiasmatic tumour and accompanying electrolyte abnormalities.

CONCLUSIONS

NF-1 is a favourable prognostic marker for VPG. Whenever possible a period of observation is necessary before treatment is initiated, during which time tumour size and visual function should be closely followed up; an untoward change in either of these is an indication for the start of treatment, preferably chemotherapy first. The combination of a globular hypothalamic/chiasmatic glioma and electrolyte abnormalities in a child without NF-1 are related to a poor prognosis.

Etoposide and thiotepa followed by ABMT (autologous bone marrow transplantation) in children and young adults with high-grade gliomas

The addition of conventional chemotherapy to irradiation has improved the outcome of children with malignant gliomas. The application of high-dose chemotherapy has been proposed as a possible way to increase the response rate and thus the survival in children with malignant brain tumours. High-dose etoposide (500 mg/m2/day x 3) and thiotepa (300 mg/m2/day x 3) followed by bone marrow transplantation were given to 22 patients (age range 4-20 years) with newly diagnosed or recurrent high-grade glioma. The response rate in the 14 assessable patients was 29% with one complete and three partial responses. 5 patients had stable disease, and 5 progressive disease. 2 patients died of treatment-related toxicity. Only 3 patients remain alive disease free 54, 60 and 65 months after high-dose therapy. For children with high-grade gliomas, survival using high-dose chemotherapy is no better than that reported with conventional treatments.

Supratentorial primitive neuroectodermal tumors in children

A retrospective review of 36 children diagnosed with a supratentorial primitive neuroectodermal tumor (PNET) at the Hospital for Sick Children was performed for the period 1970-1995. All children but one received their initial treatment at our institution. There were 18 males and 18 females and the median age at diagnosis was 35 months. Twenty-two PNETs were lobar, 3 were deep in the hemisphere, and 10 were located in the pineal region. One child presented with intracranial leptomeningeal disseminated disease. The tumors were mostly undifferentiated although 22 had some evidence of differentiation along one or more neuroepithelial lines. Five children had a biopsy, 24 had subtotal resection, and 7 had gross total resection. Twenty-six children had adjuvant radiotherapy and 13 had chemotherapy. At last follow-up 30 patients were dead and 6 were alive. The median survival was 23 months and the 2, 3, and 5 year survivals were 50%, 34%, and 18% respectively. All of the survivors received craniospinal radiation and 4 received chemotherapy. There was a statistically significantly worse survival in young children. There was a trend to better survival in children treated since 1984, and in children undergoing gross total resection. Because of the extremely poor survival, we recommended that all children undergo gross total resection followed by chemotherapy. For children older than 3 years of age craniospinal radiation should also be given.

Intracranial ependymomas of childhood. Lack of correlation of histopathology and clinical outcome

The histopathology of 66 children with the diagnosis of ependymoma who were operated on at our institution between 1954 and 1994 were reviewed. We performed an initial analysis using the entire study cohort to determine which histopathological features associated with each other in a statistically significant fashion in an attempt to identify combinations of features that together might be useful in predicting outcome. A detailed outcome analysis was then performed on the 37 most recent cases who survived the postoperative period, in whom pre- and post-imaging studies as well as long term follow-up were obtained, in order to identify the histopathological features and combinations of features that were predictive of overall and progression-free survival. Five- and ten-year progression-free survivals were 45.1% and 36.1%, respectively. Overall survivals were 57.1% and 45.0%, respectively. Of the eight individual histopathological features, only the presence of necrosis was found to correlate with a less favorable overall and progression-free survival (PFS) (p = 0.06 and 0.03, respectively). In addition, the combination of necrosis with vascular proliferation or nuclear pleomorphism was associated with a worse PFS (p = 0.01 and 0.02, respectively). However, when other clinical predictive factors were included in a multivariate regression analysis, none of the histological features or combinations of features were independently associated with outcome. In addition, no relationship was found between the pattern of rosettes (true rosette, pseudorosette, or perivascular pseudorosette) and clinical outcome. In conclusion, although this study found an association between certain histopathological features and clinical outcome in children with ependymomas, these relationships did not reach statistical significance on multivariate analysis and, thus, do not provide sufficient evidence for modifying therapy based on histopathology alone.

Pre-radiation chemotherapy for malignant glioma in adults

PURPOSE

To review our experience with pre-radiation chemotherapy for malignant glioma.

METHODS

Consecutive adults with newly diagnosed glioblastoma, anaplastic astrocytoma, anaplastic oligodendroglioma and anaplastic mixed glioma with a Karnofsky Performance Score of 60 or greater were treated with one cycle of procarbazine, lomustine and vincristine or lomustine alone, prior to radiation. Computed tomographic scans were obtained soon after surgery, eight weeks later, after radiation, and at regular intervals thereafter. The effects of chemotherapy and subsequent radiation and durations of tumor control and survival were assessed in this single arm, single center, prospective trial.

RESULTS

Thirty-seven patients started chemotherapy, 36 were rescanned eight weeks after diagnosis. Five patients (16%) responded to the first cycle of chemotherapy, three had glioblastoma and two anaplastic oligodendroglioma. Seven (19%) progressed during the first cycle, 6 had glioblastoma; with the addition of radiation one progressive case responded, three stabilized, and three continued to progress. Median times to progression and median durations of survival were 26 weeks and 60 weeks for the entire group, 24 weeks and 44 weeks for glioblastoma, and greater than 104 weeks for anaplastic astrocytoma.

CONCLUSIONS

Most patients with glioblastoma do not respond to one cycle of nitrosourea-based chemotherapy given prior to radiation, but patients with anaplastic oligodendroglioma sometimes do. Patients with anaplastic astrocytoma may not respond to one cycle of chemotherapy, but often respond to subsequent radiation. Judging by survival results, radiation can be delayed eight weeks without appearing to compromise patient outcome.

IMPLICATIONS

Pre-radiation chemotherapy with newer agents can be evaluated more fully in the future knowing that brief delays in radiation are unlikely to yield substantially inferior results.

High-grade astrocytomas in children: radiologically complete resection is associated with an excellent long-term prognosis

High-grade astrocytomas comprise approximately 10% of intracranial tumors in children. A better prognosis in children than in adults has been reported for patients with these neoplasms, although the reasons for this survival advantage are uncertain. To determine whether any consistent factors were associated with long-term survival, we reviewed the records of 31 children with high-grade non-brain stem gliomas who were treated at our institution between 1975 and 1992. Histology was reviewed and classified according to the World Health Organization scheme, and neuroimaging studies were examined to determine the extent of resection, in both instances by individuals who were unaware of the patients' outcomes. The median overall survival for the 28 patients who survived the perioperative period was 18.5 months; 10 (36%) are currently alive, with a median follow-up of 70.5 months. The median progression-free survival (PFS) was 10.5 months; eight patients (29%) remain progression-free with a median follow-up of 78 months. The extent of resection at initial operation was associated most closely with PFS and overall survival as revealed by multivariate analysis. The 14 patients who underwent subtotal (< 90%) resection and the 7 who underwent near-total (90-99%) resection had median PFS of 5.5 and 11 months, respectively (P = 0.38), and overall survival of 10.5 and 25 months, respectively (P = 0.02). None of the seven patients who underwent gross total removal of tumor as confirmed by postoperative imaging had disease progression, with a median follow-up of 84 months (P < 0.0001). All of the tumors that underwent gross total resection were situated within the cerebral hemispheres; five of the seven patients had seizures as a presenting symptom. Both tumor location and seizures were significantly associated with outcome as determined by univariate analysis, but because of the overwhelming impact of resection extent on outcome, these factors were not independently associated with outcome as revealed by multivariate analysis. Histology was associated with outcome in the subgroup of patients with incompletely resected hemispheric tumors, in which children with anaplastic astrocytoma had a significantly better PFS than those with glioblastoma multiforme (P = 0.009). In summary, our results support the role of cytoreductive surgery in the treatment of cerebral hemispheric high-grade astrocytomas in children, which may encompass a biologically distinct group of tumors that, by virtue of their location and growth characteristics, are amenable to aggressive resection. The prognosis for children with deep-seated lesions and for those with subtotally resected hemispheric lesions is generally poor with conventional therapy.

Lymphoplasmacyte-rich meningioma in a child. Case report

A rare case of lymphoplasmacyte-rich meningioma observed in a young girl is reported. The first clinical manifestations of the disease were seizures. Neuroradiological images favored the existence of a meningioma. Abnormalities in the patient's blood chemistry, principally including hypergammaglobulinemia and inflammatory syndrome, were associated with the disease. The tumor was histologically confirmed as meningioma with massive infiltrates of type B lymphocytes. The pathophysiology of the conspicuous lymphoplasmacyte infiltrates, responsible for peripheral blood abnormalities, has remained poorly understood. Alternative diagnostic hypotheses of masses that mimic this type of meningioma are discussed.

Intracranial ependymomas of childhood: long-term outcome and prognostic factors

A detailed outcome analysis was performed on 40 children with intracranial ependymomas treated at our institution between 1975 and 1993 to identify those factors that were predictive of overall and progression-free survival. Three patients (7.5%) who were treated in the first 5 years of the study died within 3 months of surgery and were excluded from further outcome assessments. Eight (22%) of the 37 patients who survived the perioperative period had evidence of leptomeningeal dissemination at presentation, on the basis of either imaging (three children) and/or cytological (six children) results. The 5- and 10-year progression-free survival rates among these 37 patients were 45.1 and 36.1%, respectively; overall survival rates were 57.1 and 45.0%, respectively. The site of progression was local in 17 of 19 patients with progressive disease. Three factors were found to have a significant association (P < or = 0.05) with the outcome on both univariate and multivariate analyses: 1) the extent of the resection, 2) the age of the patient at diagnosis, and 3) the duration of the symptoms before diagnosis. The 5-year progression-free and overall survivals were 8.9 and 22%, respectively, among patients who had evidence of residual disease on postoperative imaging studies, compared with 68 and 80% rates among patients with no apparent residual disease (P = 0.0001 and P < 0.0001, respectively). Patients younger than 3 years fared significantly worse than older children (5-year progression-free and overall survival rates of 12 and 22%, respectively, in the younger children versus 60 and 75% in older children (P = 0.003 and P = 0.01, respectively). In addition, patients with a duration of symptoms before diagnosis of < 1 month had a worse outcome than those with a more protracted course (5-year progression-free and overall survival rates of 33 and 33%, respectively, versus rates of 53 and 64%, respectively (P = 0.02 for both). Neither the finding of evidence for dissemination at presentation nor the detection of anaplastic histological features (e.g., dense cellularity or high numbers of mitoses) were associated with a significantly worse outcome in this series. The combination of variables that had the strongest association with both favorable and unfavorable outcomes was the combination of the age of the patient and the resection extent. Only 2 of 17 patients older than 3 years with gross total resections have died, whereas 13 of 20 children who were either younger than 3 years or had radiologically incomplete resections have died (P < 0.0001).(ABSTRACT TRUNCATED AT 400 WORDS)

Gene therapy for brain tumors

Gene therapy has opened new doors for treatment of neoplastic diseases. This new approach seems very attractive, especially for glioblastomas, since treatment of these brain tumors has failed using conventional therapy regimens. Many different modes of gene therapy for brain tumors have been tested in culture and in vivo. Many of these approaches are based on previously established anti-neoplastic principles, like prodrug activating enzymes, inhibition of tumor neovascularization, and enhancement of the normally weak anti-tumor immune response. Delivery of genes to tumor cells has been mediated by a number of viral and synthetic vectors. The most widely used paradigm is based on the activation of ganciclovir to a cytotoxic compound by a viral enzyme, thymidine kinase, which is expressed by tumor cells, after the gene has been introduced by a retroviral vector. This paradigm has proven to be a potent therapy with minimal side effects in several rodent brain tumor models, and has proceeded to phase 1 clinical trials. In this review, current gene therapy strategies and vector systems for treatment of brain tumors will be described and discussed in light of further developments needed to make this new treatment modality clinically efficacious.