Stephen L. Huhn

Profile of Daily Life in Children With Brain Tumors: An Assessment of Health-Related Quality of Life

PURPOSE The survival of children with CNS tumors approaches 70%, yet health-related quality of life (HRQOL) has not been investigated rigorously in this population. We aimed to show that universal assessment of HRQOL could be obtained easily by using the PedsQL 4.0 and to provide a composite profile of their daily lives. PATIENTS AND METHODS The PedsQL was administered to all patients seen in the neuro-oncology clinic at Lucile Packard Childrens Hospital (Palo Alto, CA) from December 2001, to September 2002. Patients were compared with healthy controls by using two-sided t tests to evaluate statistically significant differences. RESULTS One hundred thirty-four patients (73 male; mean age +/- standard deviation, 11.8 +/- 5.4 years; 55 had low-grade glioma, 32 had medulloblastoma/primitive neuroectodermal tumor/embryonal tumor, 17 had malignant astrocytoma, nine had germ-cell tumor, and 21 had other types of tumors) were assessed, each in less than 20 minutes. Scores on both child and parent-proxy reports for the total HRQOL, psychosocial, physical, emotional, social, and school-functioning scales were all significantly lower than controls (P < .01). Patients with low-grade glioma were reported to have the highest total HRQOL. Children receiving radiation therapy (XRT) but no chemotherapy had significantly lower total, psychosocial, emotional, and social functioning than those receiving other treatments, including XRT plus chemotherapy. CONCLUSION The PedsQL can be used to assess HRQOL rapidly and easily in children with CNS tumors, who have significantly worse HRQOL than healthy children. Children receiving XRT fare worse overall; chemotherapy added to XRT does not seem to worsen HRQOL. Assessment of HRQOL should be included as an outcome in future clinical trials.

Transplanted Stem Cell‐Secreted Vascular Endothelial Growth Factor Effects Poststroke Recovery, Inflammation, and Vascular Repair

Cell transplantation offers a novel therapeutic strategy for stroke; however, how transplanted cells function in vivo is poorly understood. We show for the first time that after subacute transplantation into the ischemic brain of human central nervous system stem cells grown as neurospheres (hCNS‐SCns), the stem cell‐secreted factor, human vascular endothelial growth factor (hVEGF), is necessary for cell‐induced functional recovery. We correlate this functional recovery to hVEGF‐induced effects on the host brain including multiple facets of vascular repair and its unexpected suppression of the inflammatory response. We found that transplanted hCNS‐SCns affected multiple parameters in the brain with different kinetics: early improvement in blood‐brain barrier integrity and suppression of inflammation was followed by a delayed spatiotemporal regulated increase in neovascularization. These events coincided with a bimodal pattern of functional recovery, with, an early recovery independent of neovascularization, and a delayed hVEGF‐dependent recovery coincident with neovascularization. Therefore, cell transplantation therapy offers an exciting multimodal strategy for brain repair in stroke and potentially other disorders with a vascular or inflammatory component. STEM CELLS 2011;29:274–285

Neuroprotection of Host Cells by Human Central Nervous System Stem Cells in a Mouse Model of Infantile Neuronal Ceroid Lipofuscinosis

Infantile neuronal ceroid lipofuscinosis (INCL) is a fatal neurodegenerative disease caused by a deficiency in the lysosomal enzyme palmitoyl protein thioesterase-1 (PPT1). Ppt1 knockout mice display hallmarks of INCL and mimic the human pathology: accumulation of lipofuscin, degeneration of CNS neurons, and a shortened life span. Purified non-genetically modified human CNS stem cells, grown as neurospheres (hCNS-SCns), were transplanted into the brains of immunodeficient Ppt1(-/)(-) mice where they engrafted robustly, migrated extensively, and produced sufficient levels of PPT1 to alter host neuropathology. Grafted mice displayed reduced autofluorescent lipofuscin, significant neuroprotection of host hippocampal and cortical neurons, and delayed loss of motor coordination. Early intervention with cellular transplants of hCNS-SCns into the brains of INCL patients may supply a continuous and long-lasting source of the missing PPT1 and provide some therapeutic benefit through protection of endogenous neurons. These data provide the experimental basis for human clinical trials with these banked hCNS-SCns.

RADIATION THERAPY FOR INTRACRANIAL GERM CELL TUMORS

PURPOSE To review the combined experiences of University of California, San Francisco, and Stanford University Medical Center in the treatment of intracranial germ cell tumors (GCT) and to assess the impact of craniospinal radiation (CSI) on patterns of relapse, progression-free survival (PFS), and overall survival (OS). PATIENTS AND METHODS Ninety-three patients received radiation for newly diagnosed intracranial GCTs, including 49 germinomas, 16 nongerminomatous GCTs (NGGCT), and 28 with no biopsy. Median follow-up for surviving patients was 4.5 years (range 0.25-34). Tests for variables correlating with OS and PFS were conducted using Cox proportional hazards model. RESULTS Five-year PFS and OS rates were 60% +/- 15% and 68% +/- 14% for patients with NGGCT and 88% +/- 5% and 93% +/- 4% for those with germinoma. Of 6 patients with localized NGGCT who did not receive CSI, 1 experienced an isolated spinal recurrence but was salvaged. Of 41 patients with localized germinoma, 6 who received CSI and 35 who did not, no isolated spinal cord relapses occurred. Twenty-one patients with localized germinoma received neither CSI nor whole brain radiation. Of these, none of 18 with ventricular radiation relapsed. One of 3 patients with primary tumor radiation relapsed intracranially but had only received 11 Gy at initial treatment. On multivariate analysis, germinoma histology but not CSI correlated with improved PFS and OS. CONCLUSION CSI is not indicated in the treatment of localized germinomas. For patients with localized germinomas treated with radiation alone, we recommend ventricular irradiation followed by primary tumor boost to a total of 45-50 Gy.

Transplantation of human central nervous system stem cells – neuroprotection in retinal degeneration

Stem cells derived from the human brain and grown as neurospheres (HuCNS‐SC) have been shown to be effective in treating central neurodegenerative conditions in a variety of animal models. Human safety data in neurodegenerative disorders are currently being accrued. In the present study, we explored the efficacy of HuCNS‐SC in a rodent model of retinal degeneration, the Royal College of Surgeons (RCS) rat, and extended our previous cell transplantation studies to include an in‐depth examination of donor cell behavior and phenotype post‐transplantation. As a first step, we have shown that HuCNS‐SC protect host photoreceptors and preserve visual function after transplantation into the subretinal space of postnatal day 21 RCS rats. Moreover, cone photoreceptor density remained relatively constant over several months, consistent with the sustained visual acuity and luminance sensitivity functional outcomes. The novel findings of this study include the characterization and quantification of donor cell radial migration from the injection site and within the subretinal space as well as the demonstration that donor cells maintain an immature phenotype throughout the 7 months of the experiment and undergo very limited proliferation with no evidence of uncontrolled growth or tumor‐like formation. Given the efficacy findings and lack of adverse events in the RCS rat in combination with the results from ongoing clinical investigations, HuCNS‐SC appear to be a well‐suited candidate for cell therapy in retinal degenerative conditions.

Central nervous system stem cell transplantation for children with neuronal ceroid lipofuscinosis

OBJECT Infantile and late-infantile neuronal ceroid lipofuscinoses (NCLs) are invariably fatal lysosomal storage diseases associated with defects in lysosomal enzyme palmitoyl-protein thioesterase 1 (PPT-1) or tripeptidyl peptidase 1 (TPP1) activity. Previous preclinical studies have demonstrated that human CNS stem cells (HuCNS-SCs) produce both PPT-1 and TPP1 and result in donor cell engraftment and reduced accumulation of storage material in the brain when tested in an NCL mouse model. METHODS HuCNS-SC transplantation was tested in an open-label dose-escalation Phase I clinical trial as a potential treatment for infantile and late-infantile NCL. Study design included direct neurosurgical transplantation of allogeneic HuCNS-SCs into the cerebral hemispheres and lateral ventricles accompanied by 12 months of immunosuppression. RESULTS Six children with either the infantile or late-infantile forms of NCL underwent low- (3 patients) and high- (3 patients) dose transplantation of HuCNS-SCs followed by immunosuppression. The surgery, immunosuppression, and cell transplantation were well tolerated. Adverse events following transplantation were consistent with the underlying disease, and none were directly attributed to the donor cells. Observations regarding efficacy of the intervention were limited by the enrollment criteria requiring that patients be in advanced stages of disease. CONCLUSIONS This study represents the first-in-human clinical trial involving transplantation of a purified population of human neural stem cells for a neurodegenerative disorder. The feasibility of this approach and absence of transplantation-related serious adverse events support further exploration of HuCNS-SC transplantation as a potential treatment for select subtypes of NCL, and possibly for other neurodegenerative disorders.

Paradoxical Cerebral Herniation Secondary to Lumbar Puncture after Decompressive Craniectomy for a Large Space-occupying Hemispheric Stroke: Case Report

OBJECTIVE AND IMPORTANCE: The risk of transtentorial herniation after removal of cerebrospinal fluid from the lumbar cistern in the setting of a supratentorial lesion with significant mass effect, increased cerebrospinal fluid pressure, or midline shift is well known. We report a case of cerebral herniation from intracranial hypotension (so-called paradoxical herniation) secondary to a lumbar puncture 1 month after decompressive hemicraniectomy for a large right hemispheric stroke. CLINICAL PRESENTATION: A 50-year-old woman was transferred to our neurosurgical service for obtundation 4 days after a lumbar puncture to rule out meningitis and 1 month after decompressive craniectomy for a large right hemispheric stroke. INTERVENTION: Eighty grams of mannitol was administered before transfer. On arrival at our hospital, the patient was intubated and a computed tomographic scan was performed. The patient was diagnosed with low-pressure herniation after review of the computed tomographic scan. Rehydration was initiated, and the patient was placed in the Trendelenburg position. She became easier to arouse, but her pupils remained dilated. She experienced a sudden severe cardiac arrhythmia leading to a cardiac arrest. Attempted resuscitation was unsuccessful, and the patient was pronounced dead. CONCLUSION: Lumbar punctures may result in lethal intracranial hypotension in patients after hemicraniectomy and are thus contraindicated unless care is taken to remove the pressure gradient of atmospheric air across the lumbar cistern.

Posterior spinal osteosynthesis for cervical fracture/dislocation using a flexible multistrand cable system: technical note

Cervical instability secondary to fracture/dislocation or traumatic subluxation involving the posterior elements may be treated by a variety of fusion techniques. The rigidity of the stainless steel wires used in posterior cervical fusions often leads to difficulty with insertion, adequate tension, and conformation of the graft construct. This report describes a technique of posterior cervical fusion employing a wire system using flexible stainless steel cables. The wire consists of a flexible, 49-strand, stainless steel cable connected on one end to a short, malleable, blunt leader with the opposite end connected to a small islet. The cable may be used in occipitocervical, atlantoaxial, facet-to-spinous process, and interspinous fusion techniques. The cable loop is secured by using a tension/crimper device that sets the desired tension in the cable. In addition to superior biomechanical strength, the flexibility of the cable allows greater ease of insertion and tension adjustment. In terms of direct operative instrumentation in posterior cervical arthrodesis, involving both the upper and lower cervical spine, the cable system appears to be a safe and efficient alternative to monofilament wires.

Spontaneous Resolution of a Prepontine Arachnoid Cyst

Prepontine arachnoid cysts are rare developmental anomalies that occur almost exclusively in children. The symptomatic child typically suffers from hydrocephalus, visual impairment, endocrine dysfunction and/or cranial neuropathies. Some cysts, however, are discovered incidentally upon prenatal or postnatal imaging for other indications. While there is little doubt that surgical treatment should be initiated to help the symptomatic child, appropriate therapy for the asymptomatic patient is unclear. Although arachnoid cysts are often managed conservatively using serial imaging, the consequences of injury to surrounding structures with prepontine cysts often lowers the threshold for intervention. The natural history of asymptomatic prepontine arachnoid cysts is unknown. It has been reported that some cysts enlarge and cause symptoms, whereas others are stable for years. This report describes an index case of spontaneous resolution of a prepontine arachnoid cyst in a female infant over a 5-year period.

The value of magnetic resonance imaging in the evaluation of fatty filum terminale.

OBJECTIVETo determine whether there are magnetic resonance imaging (MRI) characteristics of fatty fila that are correlated with neurological deficits, especially in the presence of a normal-level conus medullaris. METHODSLumbosacral MRI scans were reviewed for patients with fatty fila who were treated at Duke University Medical Center during a 5-year period. The patients were divided into three groups. Group I patients (n = 5) had fatty fila that were incidentally detected during evaluations for metastases or infections. Group II patients (n = 16) exhibited isolated low back pain but were in neurologically intact condition. Group III patients (n = 15) exhibited neurological impairments consistent with distal spinal cord dysfunction. Several characteristics were measured on the MRI scans, including the location of the conus medullaris, the filum thickness, and the distance of fat from the conus. These results were assessed for statistically significant correlation with the presence of clinical symptoms. RESULTSThe majority of patients in all three groups demonstrated the normal conus position (L2 or above) and thickened fila. The distance of fat from the conus was the only parameter that demonstrated a statistically significant difference among the groups. CONCLUSIONThe following findings were noted: 1) patients were likely to exhibit neurological deficits at a younger age (<22 yr in Group III versus 47 yr in Groups I and II); 2) a conus level below L2 was associated with neurological deficits (Group III); 3) filum thickness was not correlated with clinical presentation; 4) fat in the filum within 13 mm of the conus medullaris was most predictive of neurological deficits (Group III).