Fetal head biometry following in-utero repair of myelomeningocele.

OBJECTIVE: To evaluate the impact of prenatal myelomeningocele repair on fetal head biometry. METHODS: Fifty fetuses underwent open fetal myelomeningocele repair at our institution between January 1998 and July 2002. All had serial head circumference (HC) and lateral ventricular diameter (VD) measurements taken preoperatively and weekly for 8 weeks after repair. Cortical index (CI) was defined as HC/VD. Measurements were compared with gestational age-matched values from nomograms. One-sample t-test, ANOVA and repeated measures analysis were used to assess HC, VD and CI after fetal repair. RESULTS: Preoperatively, the HC in fetuses with myelomeningocele was smaller than control values (186.4 vs. 198.8 mm, P = 0.0004). Eight weeks' postoperatively this difference had resolved (293 vs. 301.6 mm, P = 0.76). The mean increase in CI after repair was 20% (P = 0.02) compared with the predicted 51% in normal cases. The average increase in VD was 3.9 mm (38.8%, P < 0.001). CONCLUSIONS: Mid-gestational repair of myelomeningocele alters fetal head growth. Increased CI suggests HC changes are not due to ventriculomegaly alone.

Loss of caspase-8 mRNA expression is common in childhood primitive neuroectodermal brain tumour/medulloblastoma.

Upon binding of tumour necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL), the agonistic TRAIL receptors DR4 and DR5 activate caspase-8 leading to apoptosis. In primitive neuroectodermal brain tumour (PNET) cell lines, TRAIL-induced apoptosis was recently shown to correlate with caspase-8 mRNA expression (Grotzer MA, Eggert A, Zuzak TJ, et al. Oncogene 2000, 19, 4604-4610). In this study, we analysed the expression of the TRAIL death pathway in 27 primary PNET/medulloblastoma. As shown by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR), all PNET/medulloblastoma evaluated expressed DR5, the adapter protein FADD and caspase-3, but only 48% expressed caspase-8. The mRNA expression of caspase-8 was significantly lower in primary PNET/medulloblastoma compared with normal brain samples. PCR revealed >75% methylation of the caspase-8 promoter region in three of seven PNET cell lines and in 55% of the primary PNET/medulloblastoma evaluated. In the PNET cell lines, the methylation status correlated with the caspase-8 mRNA expression. We conclude that loss of caspase-8 gene expression is common in PNET/medulloblastoma suggesting that suppression of death receptor induced apoptosis may play an important role in the pathogenesis of this common childhood brain tumour.

Angiogenic profile of childhood primitive neuroectodermal brain tumours/medulloblastomas.

Primitive neuroectodermal brain tumours (PNET) including medulloblastomas (PNET/MB) are the most common malignant brain tumours of childhood. Similar to many other brain tumours, PNET/MB often show marked neovascularisation. To determine which angiogenic factors contribute to PNET/MB angiogenesis, we examined the expression of eight angiogenic factors (vascular endothelial growth factors (VEGF, VEGF-B, VEGF-C), basic fibroblast growth factor (bFGF), angiopoetins (Ang-1, Ang-2), transforming growth factor (TGF-alpha), and platelet-derived endothelial growth factor (PDGF-A)) by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) in six PNET cell lines and 28 primary PNET/MB. Expression levels of angiogenic factors were compared with microvessel density, TrkC mRNA expression, clinical variables and survival outcomes. Our results indicate that all PNET/MB tested produce a wide range of angiogenic factors that are, individually or together, likely to play a direct role in PNET/MB tumour growth. This suggests that anti-angiogenesis approaches targeting VEGF alone may be insufficient in PNET/MB.

MYC messenger RNA expression predicts survival outcome in childhood primitive neuroectodermal tumor/medulloblastoma.

PURPOSE AND EXPERIMENTAL DESIGN: Cerebellar primitive neuroectodermal tumors/medulloblastomas (PNET/MB) are the most common malignant brain tumors in childhood. To identify PNET/MB biological prognostic factors that define a patient group with a sufficiently good prognosis to permit a reduction in treatment intensity, we determined the expression levels of MYC mRNA in fresh frozen tumor samples from 26 PNET/MB patients using semiquantitative reverse transcription-PCR. RESULTS: MYC mRNA expression levels in primary PNET/MB showed a wide range with a 22-fold difference between the highest and lowest values and did not correlate with MYC gene amplification. MYC mRNA expression was an independent significant prognostic factor for progression-free survival outcome and was more predictive than standard clinical factors. The combination of low MYC mRNA expression and high TrkC mRNA expression identified a good outcome group of PNET/MB patients (n = 7) with 100% progression-free survival after a median follow-up time of 55 months (range, 15-91 months). Three of these seven good outcome patients survived without radiotherapy. CONCLUSIONS: Low MYC mRNA expression is a powerful independent predictor of favorable clinical outcome in PNET/MB. Assessment of MYC mRNA levels is feasible and may be incorporated in prospective PNET/MB clinical trials to aid in treatment planning for patients with PNET/MB on confirmation of our results in larger studies.

The Rationale for in utero repair of myelomeningocele.

OBJECTIVES: Despite advances in prenatal diagnosis, management of fetal myelomeningocele has been limited to abortion or supportive postnatal care. The rationale for fetal repair of myelomeningocele and initial clinical outcomes are discussed. METHODS: A complete review of the literature concerning fetal myelomeningocele and repair was performed. RESULTS: While myelomeningocele is a primary embryologic disorder, neurologic damage is also secondary to progressive in utero damage to the exposed spinal cord. Animal models with midgestational coverage of the spinal defect demonstrate near normal neurologic function at term. Early clinical results suggest that fetal closure can salvage neurologic function, reverse hindbrain herniation, and diminish the need for ventriculoperitoneal shunting. CONCLUSIONS: In utero repair of myelomeningocele may improve neurologic outcomes and reduce hindbrain herniation in selected patients.

Development of the Spitz-Holter valve in Philadelphia.

The history of the treatment for hydrocephalus dates back to the Fertile Crescent thousands of years ago. Despite three millennia of management, significant advances in the surgical treatment of the disease have been infrequent. During the 1950s, a milestone occurred at the Children's Hospital of Philadelphia, with the successful development of the first working shunt valve for the treatment of hydrocephalus. In this historical vignette, based on recent interviews with John Holter, D.Sc. (Hon) and Eugene Spitz. M.D., and on a review of the available literature, the authors narrate the exciting story of the development of the Spitz-Holter valve, which took place in Philadelphia during the early 1950s.

High microvessel density in primitive neuroectodermal brain tumors of childhood.

Microvessel density (MVD), a measure of tumor angiogenesis, has been shown to correlate significantly with overall and progression-free survival outcomes in various cancers including astrocytic brain tumors. To assess if the MVD is an independent prognostic factor in primitive neuroectodermal tumors (PNET) of the central nervous system, formalin-fixed paraffin-embedded tumor sections of 78 children with PNET were studied by CD34 immunohistochemistry to highlight endothelial cells. Microvessel density was determined in the most active area of neovascularization according to well-established methods. While it was shown that MVD showed considerable inter-tumor variability (median 75; range 20-345 microvessels per 0.7 mm2 field), no significant associations were found between MVD and metastasis or survival outcomes. We conclude that many PNETs are highly vascular CNS tumors, indicating potent angiogenic activity. Therefore, these tumors would be good candidates for antiangiogenic strategies. However, MVD determined in the most active area of neovascularization is not a predictor of metastatic potential or survival outcomes in childhood PNET.

Antitumor activity of the rapamycin analog CCI-779 in human primitive neuroectodermal tumor/medulloblastoma models as single agent and in combination chemotherapy.

We examined the cytotoxicity of the immunosuppressant agent rapamycin and its analogue CCI-779 in human brain tumor cell lines in vitro and in vivo as single agents and in combination with standard chemotherapeutic drugs. In the rapamycin-sensitive PNET/MB cell line DAOY, rapamycin exhibited additive cytotoxicity with cisplatin and with camptothecin. In vivo, CCI-779 delayed DAOY xenograft growth by 160% after 1 week and 240% after 2 weeks of systemic treatment, compared with controls. Single high-dose treatment induced 37% regression of tumor solume. Growth inhibition of DAOY xenografts was 1.3 times greater after simultaneous treatment with CCI-779 and cisplatin than after cisplatin alone. Interestingly, CCI-779 also produced growth inhibition of xenografts derived from U251 malignant glioma cells, a human cell line resistant to rapamycin in vitro. These studies suggest that the rapamycin analogue CCI-779 is an important new agent to investigate in the treatment of human brain tumors, particularly PNET/MB.

Abundance of apoptotic neoplastic cells in diagnostic biopsy samples is not a prognostic factor in childhood primitive neuroectodermal tumors of the central nervous system.

PURPOSE: To assess if the abundance of apoptotic tumor cells is an independent prognostic factor in primitive neuroectodermal tumors (PNET) of the central nervous system. PATIENTS AND METHODS: Formalin-fixed paraffin-embedded tumor tissue sections from 78 clinically well-characterized children with PNET were evaluated by terminal deoxytransferase-mediated deoxyuridinie-5'-triphosphate (dUTP) nick-end labeling (TUNEL). Apoptotic indices (AI) were determined by counting TUNEL-positive tumor cells either in the highest staining region (AI hot spot) or in at least 15 randomly chosen fields (AI random). The AI hot spot and AI random were then correlated with clinical variables and survival outcome. RESULTS: AI hot spot (median 0.56%; range 0%-6.54%) and AI random (median 0.30%; range 0%-3.21%) showed considerable intertumor variability. Moreover, 53% of the evaluated PNET showed a more than two-fold difference between AI hot spot and AI random, showing important intratumoral variability of the abundance of apoptotic cells in a subset of the evaluated PNET. No significant associations were found between AI hot spot and AI random with clinical variables or survival outcome. CONCLUSION: The apoptotic index does not predict survival outcome and is not specifically associated with clinical variables of prognostic significance in childhood PNET.

Complete spontaneous resolution of childhood Chiari I malformation and associated syringomyelia.

The diagnosis of Chiari I malformation and associated syringomyelia is often made in childhood. Since the advent of magnetic resonance imaging, these abnormalities are increasingly detected incidentally. Despite incomplete understanding of the natural history of asymptomatic Chiari I malformations, the current recommendation is to consider prophylactic surgical intervention in those with an associated syringomyelia. This case report presents a complete spontaneous resolution of a Chiari I malformation and syringomyelia in a child. It illustrates the possibility that asymptomatic children with Chiari I malformations and syringomyelia may be followed conservatively.

Fetal neurosurgery.

SURGERY BEFORE BIRTH has been performed for lethal conditions for several years. The techniques that have been developed are being applied to nonlethal conditions such as meningomyelocele. It is possible that fetal surgery might find a place in the management of certain forms of hydrocephalus as well. The challenge is to define which patients might benefit from such radical procedures before these techniques are accepted as standard care.

A novel kinase, AATYK induces and promotes neuronal differentiation in a human neuroblastoma (SH-SY5Y) cell line.

Apoptosis Associated Tyrosine Kinase (AATYK), a novel protein recently isolated from differentiating 32D mouse myeloid cells, contains a putative tyrosine kinase domain and several binding motifs for src homology 2 (SH-2) and src homology 3 (SH-3) domain containing proteins. We observed that AATYK is expressed in different regions of the brain. Although it might play a role in normal nervous system development by modulating apoptosis, little is known regarding its function in the brain or its intracellular localization and kinase activity. Recognizing its homology with Insulin like growth factor-I (IGF-I) receptor (IGF-IR) and the critical role of IGF-I in neuronal survival, we hypothesized that AATYK plays an important role in neuronal differentiation/apoptosis. To test this hypothesis, we transfected the human adrenergic neuroblastoma (NB):SH-SY5Y cells with AATYK cDNA under a tetracycline-repressible promoter and established stable cell lines that readily express AATYK on removal of tetracycline. AATYK immunoprecipitated from these cell lysates is an active kinase. Indirect immunofluorescent staining of the clones revealed AATYK to be localized in the cytoplasm. By itself, AATYK overexpression for short duration (2-3 days) did not induce differentiation in the stable SH-SY5Y clones. On the other hand, overexpression for longer periods (7-8 days) per se, significantly (P<0.05-0.001) increased the percent of differentiated cells as well as the neurite length. AATYK-induced differentiation was in the same range as the differentiation induced by agents like all-trans retinoic acid (RA), 12-O-Tetradecanoyl phorbol 13-acetate (TPA) and IGF-I. In addition, AATYK significantly promoted the neuronal differentiation induced by these agents. Our results demonstrate for the first time that AATYK is an active, non-receptor, cytosolic kinase which induces neuronal differentiation and also promotes differentiation induced by other agents in the SH-SY5Y cells.

TrkC expression predicts good clinical outcome in primitive neuroectodermal brain tumors.

PURPOSE: To identify biologic prognostic factors in childhood primitive neuroectodermal tumors (PNET), including medulloblastoma, that accurately define patient groups with sufficiently good prognosis to permit a reduction in treatment intensity. PATIENTS AND METHODS: We determined expression levels of the neurotrophin receptor TrkC mRNA in formalin-fixed tumor samples from 87 well characterized PNET patients using in situ hybridization. Comparison of TrkC mRNA expression levels with clinical and other laboratory variables was performed using univariate and multivariate Cox regression analysis. RESULTS: High TrkC mRNA expression was found to be associated more with higher 5-year cumulative survival rate than was low TrkC mRNA expression (89% v 46%, respectively). When compared with established clinical prognostic factors and laboratory variables of potential prognostic significance, TrkC mRNA expression, by univariate analysis, was found to be the single most powerful predictor of outcome (hazards ratio, 4.81; P <.00005), exceeding all clinical prognostic factors. In multivariate analysis, the hazards ratio remained significant (P <.00005). CONCLUSION: High TrkC mRNA expression in PNET is a powerful independent predictor of favorable clinical outcome. Assessment of TrkC mRNA levels may aid in treatment planning for patients with PNETs and should be incorporated prospectively into PNET clinical trials.

Autocrine secreted insulin-like growth factor-I stimulates MAP kinase-dependent mitogenic effects in human primitive neuroectodermal tumor/medulloblastoma.

Primitive neuroectodermal tumors/medulloblastoma (PNET/MB) have similarities to neuroectodermal progenitor cells of the developing CNS. Since insulin-like growth factor I (IGF-I) exerts pleiotrophic effects on cells in the developing CNS, we evaluated the production, mitogenic effects and signaling pathways of IGF-I in PNET/MB cells and found that IGF-I is an autocrine growth factor in human PNET/MB cell lines tested. Stimulation of DAOY cells by IGF-I led to phosphorylation of its cognate receptor (IGF-IR) and resulted in cell proliferation. These effects of IGF-I were suppressed by IGF-IR blocking antibodies and by PD 98059, MAP kinase pathway inhibitor. The results demonstrate the existence of an autocrine IGF-I/IGF-IR loop and indicate that IGF-I promotes proliferation via MAP kinase pathway.

Surgically treated lumbar disc disease in the pediatric population: an outcome study.

OBJECT: This outcome study was undertaken to investigate the long-term results obtained in surgically treated pediatric patients with lumbar disc disease by using standardized medical outcome scales and clinical follow-up examination. METHODS: Twenty nine patients 17 years of age or younger underwent surgery between 1968 and 1998 for lumbar disc disease. The follow-up period ranged from 4 months to 30.5 years (mean 8.5 years). Outcome scores (health profiles) were generated using a standardized medical outcome scale, the Short Form health survey questionnaire (SF-36), and a condition-specific back pain outcome scale. Clinical follow-up data were obtained by telephone interview. The health profile of the study population closely paralleled that of the normal population and was distinctly different from the health profile of adults with low-back pain. Only physical functioning, as measured by a scale of the SF-36, was found to be impaired in a subset of the study population. The rate of reoperation was 24% over the course of the follow-up period. In contrast to similar studies in adults, there were no identifiable predictive factors for either reoperation or poor outcome. CONCLUSIONS: Lumbar disc disease in the pediatric population does not appear to lead to chronic complaints of back pain, and it does not appear to have a negative impact on overall health. This finding suggests that pediatric lumbar disc disease may be a separate entity distinct from adult lumbar disc disease, and therefore, the same conclusions regarding long-term outcome cannot be applied to the pediatric population.

Antitumor activity of a human cytotoxic T-cell line (TALL-104) in brain tumor xenografts.

Malignant glioma in adults and primitive neuroectodermal tumors/medulloblastomas in children are the most common malignant primary brain tumors that either respond poorly to current treatment or tend to recur. Adoptive therapy with TALL-104 cells-an IL-2-dependent, major histocompatibility complex nonrestricted, cytotoxic T-cell line-has demonstrated significant antitumor activity against a broad range of implanted or spontaneously arising tumors. This study investigates distribution of systemically and locally administered TALL-104 cells and their efficacy in effecting survival of a rat model of human brain tumor. In vitro, TALL-104 cells showed significant cytotoxic activity when added to human glioblastoma cell lines U-87 MG, U-251 MG, and A1690; the medulloblastoma cell lines DAOY, D283 Med, and D341 Med; and the epidermoid cancer cell line A431. In brain tumor-bearing rats, the amount of fluorescent dye-labeled TALL-104 cells in brain increased after they were given by intracarotid injection as compared with i.v. cell administration. However, TALL-104 cells rapidly decreased to low levels within 1 h after intracarotid injection. This finding suggests that TALL-104 cells given systemically may not invade brain or tumor tissues, but rather may remain in the vascular system, making this approach less efficient for brain tumor treatment. In a model of athymic rats engrafted with human A431 carcinoma brain tumor, repetitive local administration of TALL-104 cells directly into the tumor bed resulted in a significant increase in survival time compared with control animals. Therefore, local therapy with TALL-104 cells may be a novel and highly effective treatment approach for malignant brain tumors.

Quality of life of adult survivors of germinomas treated with craniospinal irradiation.

OBJECTIVE: To assess the quality of life (QOL) of a group of patients treated for intracranial germinoma with biopsy followed by prophylactic whole-neuraxis radiation therapy. METHODS: The Short-form-36 and Functional Assessment of Cancer Therapy QOL questionnaires were completed by 22 of 27 eligible adults treated with whole-neuraxis irradiation for biopsy-proven, marker-negative intracranial germinomas between 1976 and 1996. In addition, data were obtained regarding height and weight, medications, ability to work, and educational achievement. RESULTS: The patients' QOL was generally good. All of the patients are in or have completed high school; nine are in or have completed college, and five have advanced degrees. Patients rated themselves lower on the physical composite scale of the Short-form-36 (average, 46 versus 54 in a normal population). On the mental composite scale, patients rated themselves more favorably than the normal population (average, 54 versus 49 in a normal population). Patients were normally proportioned for height and weight, but female patients tended to be short. Age at radiation did not correlate with QOL. CONCLUSION: The QOL of adults treated for marker-negative germinoma with prophylactic whole-neuraxis irradiation is generally good. These data should serve as a benchmark for newer treatment protocols eliminating or reducing radiation.

Extrarenal nephroblastic proliferation in spinal dysraphism. A report of 4 cases.

Four cases of extrarenal nephrogenic proliferation in the sacrococcygeal region with spinal dysraphism are presented. In two of the cases, features of Wilm's or incipient Wilm's tumor were present. The previous literature on sacrococcygeal nephrogenic tissue is reviewed, and the impact of these findings on the histogenesis of extrarenal sacrococcygeal Wilm's tumor is discussed.

Improvement in hindbrain herniation demonstrated by serial fetal magnetic resonance imaging following fetal surgery for myelomeningocele.

CONTEXT: Hindbrain herniation occurs in a large percentage of children with myelomeningocele and is the leading cause of death in this population. The effect of early fetal closure of myelomeningocele on hindbrain herniation is unknown. OBJECTIVE: To determine whether early fetal closure of myelomeningocele affects hindbrain herniation. DESIGN: Case series of patients undergoing fetal myelomeningocele closure with serial measurements of hindbrain herniation and a mean follow-up of 182 days. SETTING: Tertiary care medical center. PARTICIPANTS: Ten patients undergoing fetal myelomeningocele closure at 22 to 25 weeks' gestation between March 1998 and February 1999. MAIN OUTCOME MEASURES: Need for shunt placement; degree of hindbrain herniation (grades 0-3) found on magnetic resonance imaging (MRI) performed prior to surgery and 3 and 6 weeks after fetal surgery, as well as shortly after birth; gestational age at delivery. RESULTS: All initial fetal MRI scans performed at 19 to 24 weeks' gestation showed significant (grade 3) cerebellar herniation and absence of spinal fluid spaces around the cerebellum. Six fetuses were delivered electively at 36 weeks' gestation after lung maturity was established. The other 4 were delivered prematurely, at 25, 30, 30, and 31 weeks of gestation, and the 25-week gestation neonate died. All 9 surviving neonates showed improvement in the hindbrain hernia at the 3-week postoperative fetal scan (grade 2, n = 4; grade 1, n = 5). On the postnatal scan, all patients showed grade 1 hindbrain herniation. Only 1 patient required placement of a ventriculoperitoneal shunt. CONCLUSION: In this series of patients, fetal myelomeningocele closure resulted in improvement in hindbrain herniation as demonstrated by serial MRI scans.