Metastatic juvenile pilocytic astrocytoma. Case report

Comparison of adult and pediatric pilocytic astrocytomas using competing risk analysis: A population-based study

BACKGROUND

Pilocytic astrocytoma(PA) is a relatively benign tumor occurring primarily in the pediatric population. Comparison of characteristics and survival of this tumor between adult and pediatric patients in a single, population-based study is yet to be performed.

OBJECTIVE

We aimed to directly compare the characteristics and survival of pilocytic astrocytoma between pediatric and adult patients in a single, population-based study.

METHODS

We utilized the SEER database using data from 1983 to 2016. All patients with histologically confirmed, intracranial pilocytic astrocytoma were included and divided into a pediatric(age<18 years) or adult group. Due to lower risk of tumor-specific-mortality, we utilized a competing risk analysis to account for mortality from other causes. Univariable and multivariable competing risk analysis(CRA) was performed, and sub-distribution hazard ratio(SHR) or adjusted SHR(aSHR) was reported.

RESULTS

A total of 4357 patients comprised the final cohort, with 3014(69.2%) pediatric patients. As compared to the pediatric group, adult patients were predominantly White(p < 0.01), with PA less likely fully resected(p = 0.01), smaller tumor size(p < 0.01), and were less often located in the cerebellum(p < 0.01). Multivariable CRA revealed a worse prognosis for the adult group(p < 0.01), regional or distal extension(p < 0.01), and non-cerebellar locations including frontal(p < 0.01), parietal(p < 0.01), ventricular(p < 0.01) or brainstem(p < 0.01). Improved prognosis was seen with more recent year-of-diagnosis(2003-2016, p = 0.03), gross-total/total resection(p < 0.01), and biopsy only patients(p = 0.02).

CONCLUSIONS

Pilocytic astrocytomas in adult patients have a worse prognosis than pediatric patients. Cumulative incidence of cancer-specific-mortality is higher in adults when adjusted for other factors. PAs with regional or distal extension and non-cerebellar locations carry worse outcomes. Surgery remains an effective treatment and GTR/TR should be achieved when possible.

Clinical characteristics and prognostic factors of adult patients with pilocytic astrocytoma

Introduction

Pilocytic astrocytoma (PA) is the most common primary brain neoplasm in children and treated in curative intent with gross total resection (GTR). However, PA is rare in adults, resulting in limited knowledge on the natural clinical course. This study aimed to describe the clinical course and identify prognostic factors of adult patients with PA.

Methods

46 patients ≥ 18 years at diagnosis of PA and neurosurgical resection or biopsy between 2000 and 2018 were identified from the Neuro-Biobank of the Medical University of Vienna. In two cases with differing histopathological diagnosis at recurrence, DNA methylation analysis was performed using Illumina Infinium HumanMethylation850 BeadChip (850 k) arrays and the Molecular Neuropathology classifier. Clinico-pathological features were correlated with patient outcomes.

Results

Median age at diagnosis was 32.5 years (range: 19–75) and median Ki67 proliferation index was 2.8% (0.5–13.4%). Tumor location significantly correlated with resectability (p < 0.001). Tumor progression or recurrence was observed in 9/46 (19.6%) patients after a median follow up time of 53.0 months (range 0.5–300). 5-year overall and progression-free survival rates were 85.3% and 70.0%, respectively. 2/9 (22.2%) patients presented with histological changes in the recurrent tumor specimen. In detail, methylation classification redefined the histological diagnosis to anaplastic astrocytoma with piloid features and glioma in one patient, each. Age > 40 and higher body mass index (BMI) were associated with impaired progression-free and overall survival (p < 0.05).

Conclusions

Tumor recurrence or progression in adult PA patients was higher than the one reported in pediatric patients. Higher age and BMI were associated with impaired prognosis.

Stachydrine suppresses viability & migration of astrocytoma cells via CXCR4/ERK & CXCR4/Akt pathway activity

AIM

Pilocytic astrocytomas (PAs) are a common adolescent malignancy. We evaluated the effects of the betaine stachydrine on human PA cells as well as its associated molecular mechanism(s).

MATERIALS & METHODS

Various experiments assessing stachydrine's effects on the human PA cell line Res186 were performed.

RESULTS & CONCLUSION

Stachydrine dose-dependently suppressed proliferation and colony formation in Res186 cells with no such effect on normal astrocytes. Stachydrine downregulated CXCR4 transcription through enhancing IκBα-based NF-κB inhibition. Stachydrine promoted apoptosis and cyclin D1/p27^Kip1-associated G0/G1 phase arrest in a CXCR4/ERK- and CXCR4/Akt-dependent manner. Stachydrine suppressed MMP-associated migration and invasiveness via inhibiting CXCR4/Akt/MMP-9/2 and CXCR4/ERK/MMP-9/2 pathway activity. Stachydrine inhibits the viability, migration and invasiveness of human PA cells via inhibiting CXCR4/ERK and CXCR4/Akt signaling.

Pilocytic astrocytoma of the cerebellopontine angle mimicking vestibular schwannoma: report of a rare entity

We present a rare case of a 55-yr old patient of pilocytic astrocytoma of the cerebello-pontine angle mimicking a vestibular schwannoma. The tumor protruded into the porus acusticus causing enlargement of the internal auditory meatus, which is quite an unusual feature of glial tumours.

Suprasellar pilocytic astrocytoma in an adult with hemorrhage and leptomeningeal dissemination: case report and review of literature

Pilocytic astrocytoma (PA) is a low-grade tumor. It has an excellent prognosis after total resection. Leptomeningeal dissemination and hemorrhage are very rare to be associated with PA and lead to unfavorable prognosis. A 35-year-old man was diagnosed with a hemorrhagic suprasellar PA in 2006. Subsequent examination in 2007 revealed another large subdural hemorrhagic lesion in the sacral region, which proved to be PA by histopathologic assessment. Other leptomeningeal foci were discovered mainly at the craniocervical junction. The patient underwent subtotal resection and received chemotherapy with disease control for 7 years. Progression of the disseminated disease has recently occurred; however, the patient is still alive with stable disease after radiotherapy. The radiological features, management, and relevant literature are also presented. Our report heightens the awareness of PA in the adult population and the importance of close surveillance for the leptomeningeal spread, especially for sellar region tumors.

Cranial Pilocytic Astrocytoma With Spinal Drop Metastasis in an Adult: Case Report and Literature Review

BACKGROUND

Pilocytic astrocytoma (PA) is a benign neoplasm that typically occurs in the brain within the pediatric and adolescent age groups and is uncommon in adults. It rarely occurs within the ventricles, and the overall prognosis is favorable. A PA of the brain with spinal metastasis at presentation has never been reported in an adult.

CASE DESCRIPTION

We report a case of a 47-year-old man presenting with sudden-onset frontal headache associated with nausea and lethargy in addition to a background of a longer history of back pain and headache. Radiologic imaging revealed an acute intraparenchymal hemorrhage in the right parieto-occipital lobes with intraventricular extension within a peripherally enhancing heterogeneous lesion. Magnetic resonance imaging of the spine revealed a sacral intradural tumor. The patient underwent surgical resection of the intracranial mass followed by debulking of the spinal lesion. Histopathologic study revealed that both the cranial and spinal tumors were PA.

CONCLUSIONS

This case illustrates a unique instance of hemorrhage into a cerebral PA with a spinal metastasis. To our knowledge, this is the first such case reported in an adult. We review the literature on the subject.

Metastatic Low-Grade Gliomas in Children: 20 Years' Experience at St. Jude Children's Research Hospital

BACKGROUND

Patients with low-grade gliomas (LGG), which are the most common childhood brain tumors, have excellent long-term survival. Dissemination of LGG is rare. Robust data on the incidence, presentation, patterns of dissemination, disease behavior, outcome, and best-management approaches do not exist. We describe 20 years of follow-up of children with metastatic LGG.

PROCEDURE

Data collected during the period 1990-2010 were retrospectively reviewed for the following inclusion criteria: diagnosis of metastatic LGG, age younger than 21 years at initial diagnosis, and magnetic resonance imaging of the brain and/or spine at diagnosis and/or follow-up. Patient demographics, pathology, treatment modalities, and outcome were reviewed.

RESULTS

Of 599 patients with LGG, 38 (6%) had metastatic disease at either diagnosis or follow-up. Most tumors (87%) were located in the brain, and half of the patients had metastatic disease at presentation. The most common diagnosis was pilocytic astrocytoma (55%). Chemotherapy was the most common initial treatment modality. Median survival of the group was 6.2 years (range, 0.1-16.9 years). Fifteen (40%) patients died at a median of 6 years from diagnosis (range, 0.8-15 years). Overall survival at 5, 10, and 15 years was 80.7 ± 6.6%, 63.0 ± 10.2%, and 50.9 ± 16.0%, respectively.

CONCLUSION

This study describes the longest follow-up of children with metastatic LGG. LGG is underestimated and entails major morbidity and mortality. Prospective studies are needed to learn the true incidence, study the biology, and determine the best approaches to diagnosis, treatment, and follow-up.

Pilocytic astrocytoma with leptomeningeal dissemination

PURPOSE

Pilocytic astrocytoma (PA) is a common pediatric glioma that is generally characterized by indolent growth. However, there are reports of PA disseminating throughout the central nervous system. Given the rarity of dissemination, the appropriate treatment for these patients is poorly defined. In this case series, we describe the clinical characteristics and treatment outcomes of six children treated for disseminated PA at our institution and review the current published literature.

METHODS

Six cases of disseminated PA treated at the University of Texas MD Anderson Cancer Center were identified. Demographics, disease characteristics, and follow-up data were compiled. Fifty-three reported cases were identified in the published literature.

RESULTS

Our cohort's mean age at presentation was 7 years, and the mean time to identification of disseminated disease was 12 months after initial diagnosis. Two patients underwent chemotherapy, and all underwent proton beam radiation therapy to all or part of the craniospinal axis. With a median follow-up of 24 months after radiation therapy, five of six patients were alive, four with stable disease and one with progressive disease.

CONCLUSIONS

Treatment of disseminated PA is frequently multi-modal, including surgical resection, chemotherapy, and radiation therapy. On the basis of early clinical data, extended-field radiation therapy is a viable option for treating disseminated PA.

Pediatric primary pilocytic astrocytoma of the cerebellopontine angle: a case report

INTRODUCTION

We describe a rare case of pediatric pilocytic astrocytoma presented as a right cerebellopontine angle (CPA) mass, completely separated from the brain stem and arising from the proximal VIII nerve portion.

CASE REPORT

A 12-year-old boy, with no evidence of neurofibromatosis type 2, presented with progressive hearing loss at the right ear and headache. An initial enhanced magnetic resonance examination suggested the diagnosis of schwannoma. The tumor was resected by a suboccipital retrosigmoid approach.

DISCUSSION

Our case seems to be the first report of a primary pediatric CPA pylocitic astrocytoma arising from the VIII nerve complex and presenting internal auditory canal enlargement. It represents the third reported case of a primary CPA pilocytic astrocytoma (the second pediatric case with the first arising from V nerve) and the eighth report of primary CPA glioma, overall. We discuss the clinical, neuroradiological, and intraoperative findings, and we review the different hypothesis about the origin of these rare tumors.

Management of optic-hypothalamic gliomas in children: still a challenging problem

Optic pathway-hypothalamic gliomas (OPHGs) are rare, often unresectable tumors that mostly occur in childhood. Their biological behavior is unpredictable, although they tend to follow an aggressive clinical course in infants and a benign course in children with neurofibromatosis type 1. Optimal management is still controversial. Nonprogressing OPHGs are usually followed by surveillance alone. Surgery is advocated for progressing tumors to decompress the optic pathways, obtain a quick relief from intracranial hypertension and allow histologic examination (when needed). The current trend is in favor of conservative surgical behavior, except for resectable tumors. Chemotherapy is increasingly used in the management of OPHGs, especially in infants, to delay radiotherapy. Carboplatin and vincristine are the most frequently used drugs, although several chemotherapeutic agents in different combinations are currently employed with good results. Radiotherapy is utilized in children over 5 years of age as an adjuvant or as an alternative to surgery. The prognosis of OPHGs is quite good, with regard to the overall survival rate (70-100% at 5 years), but less favorable in terms of late morbidity.

Dissemination patterns of pilocytic astrocytoma

Two patients with multifocal pilocytic astrocytoma diagnosed by magnetic resonance imaging (MRI) and confirmed by histopathological examination are reported. They presented distinct sites and mechanisms of metastasis: to distant ventricles through the cerebral spinal fluid (CSF) in patient 1 and to contralateral parenchyma, possibly through white matter tracts, in patient 2, a pathway not so far reported in pilocytic astrocytoma. Early detection of multifocal pilocytic astrocytoma by MRI may change treatment strategies and improve prognosis.

Les astrocytomes pilocytiques du diencéphale de l’enfant

BACKGROUND AND PURPOSE

Pilocytic astrocytoma (PA) is a WHO grade I tumor of the central nervous system mostly arising in children and young adults. Management of diencephalic PA is a difficult challenge. Surgical treatment has to cope with both the difficulties of deep location and eloquent area tumors.

MATERIALS AND METHODS

We retrospectively reviewed seven pediatric cases (female: 4, male: 3) of diencephalic PA. Opto-chiasmatic tumors were excluded from the series. Mean age at diagnosis was 108 months (9 years) (range: 4 month-18 years), median age was 111 months. Median follow-up for the series was 125 months. Tumor locations were as followed: right thalamus: 2, both thalami: 1, hypothalamus: 3, and right basal ganglia: 1. At the onset, the first symptom was mostly raised intracranial pressure. The delay in diagnosis ranged from 48 hours up to 6 years.

TREATMENT

a shunting procedure was performed in 3 patients, a direct surgical approach in 5 patients (gross total removal: 2; partial removal: 3) and one patient had only a biopsy. Three children were re-operated. Three patients were treated by radiationtherapy (RT) after surgery. Chemotherapy was delivered for 4 children.

RESULTS

The overall survival rate was 71.4 months (almost 6 years) (range: 3-184 months). Median survival rate was 42 months (3.5 years). Three children died, two by tumor progression and one death related to late side-effects of RT. Four patients have a good quality of life with GOS I (n = 3) or II (n = 1). We observed tumor regression in two patients at 1 and 17 years after the beginning of treatment. Correct diagnosis was only made for two cases at the initial pathological examination.

CONCLUSION

The course of diencephalic PA is still unpredictable. The tumor can be controlled by a partial surgical removal, and a residual tumor can sometimes decrease in size after surgery. Gross total removal of these tumors, although difficult, may be performed. With cranial navigation systems, the risk is low. Pathological diagnosis is sometimes difficult to assess.

From the archives of the AFIP: pilocytic astrocytoma: radiologic-pathologic correlation

Pilocytic astrocytoma is the most common pediatric central nervous system glial neoplasm and the most common pediatric cerebellar tumor. This tumor has a noteworthy benign biologic behavior that translates into an extremely high survival rate-94% at 10 years-that is by far the best of any glial tumor. Most patients present in the first 2 decades, and clinical symptoms and signs are usually of several months duration and directly related to the specific location of the tumor. The cerebellum, optic nerve and chiasm, and hypothalamic region are the most common locations, but the tumor can also be found in the cerebral hemisphere, ventricles, and spinal cord. Surgical resection is the treatment of choice for all tumors, except for those involving the optic pathway and hypothalamic region, which may be treated with radiation therapy and chemotherapy. Cross-sectional imaging often demonstrates a classic appearance: a cystic mass with an enhancing mural nodule. Less common appearances are quite nonspecific. Surrounding vasogenic edema is rarely present, and this feature provides a valuable clue to the correct diagnosis. Accurate interpretation of imaging studies plays an essential role in directing treatment of these tumors, particularly when they arise in the optic pathway of patients with neurofibromatosis type 1. Disseminated disease and recurrence are extremely rare.

Leptomeningeal cancer in the pediatric patient

The treatment and prophylaxis of leptomeningeal leukemia and lymphoma in children has dramatically improved disease control and long-term survival. However, the treatment of other leptomeningeal cancers has been less successful and the neurologic morbidity associated with central nervous system-directed therapy has a significant long-term impact on quality of life. Further research is critical to identify new therapeutic strategies for children with or at high risk for leptomeningeal cancer.

Spinal seeding of a pilocytic astrocytoma following multiple subtotal resections

We report the case of a 4-year-old girl presenting with spinal and leptomeningeal dissemination following several subtotal resections of cerebellar pilocytic astrocytomas.

New variants of malignant glioneuronal tumors: a clinicopathological study of 40 cases

OBJECTIVE

To demonstrate that malignant glioneuronal tumors comprise a large spectrum of neoplasms, without mature ganglion-like cells, that may histologically resemble any malignant glioma (World Health Organization Grade III or IV) but have a distinct biological behavior.

METHODS

This series includes all tumors diagnosed as malignant glioneuronal tumors (MGNTs) in our routine practice during a 2-year period during which neurofilament protein (NFP) immunostaining was performed in any case of suspected malignant glioma with unusual clinical, radiographic, and/or histological features. Immunostaining using neuronal markers (NFP, NeuN, synaptophysin, and chromogranin) and glial fibrillary acidic protein was done on paraffin sections after antigen retrieval. The presence of NFP-positive tumor cells, including those in mitosis, was used as a hallmark diagnostic criterion of MGNT.

RESULTS

All tumors coexpressed glial fibrillary acidic protein and NFP. Other neuronal markers tested were inconstantly expressed. No recurrence was observed at the primary site in 36.4% of patients who underwent gross total resection. Twelve patients (33.3%) developed intra-axial and/or systemic metastases, and 4 were free of disease at 39 to 184 months. Univariate analysis revealed that gross total surgical resection was the most important prognostic factor predicting survival (44 versus 15 mo; P < 0.0001), followed by a long duration of symptoms (>1 yr; P = 0.005), young age at symptom onset (children versus adults; P = 0.045), and absence of necrosis (P = 0.02). Gross total surgical resection (P = 0.001) and a long duration of symptoms (symptoms > 1 yr; P = 0.013) proved to be independent and statistically significant prognostic factors in the multivariate analysis.

CONCLUSION

NFP immunostaining is required to identify MGNTs accurately. Their distinction from malignant gliomas is of paramount clinical importance, particularly for neurosurgeons, because gross total surgical resection may be curative in some cases. Finally, MGNTs may account for the long-term survival and/or occurrence of metastases demonstrated in a subset of malignant gliomas.

Management of pilocytic astrocytoma with diffuse leptomeningeal spread: two cases and review of the literature

INTRODUCTION

Leptomeningeal dissemination of juvenile pilocytic astrocytoma (JPA) is a rare event. We report two children with disseminated JPAs treated with a chemotherapeutic agent, temozolomide, after progression of the disease despite surgery, traditional chemotherapy, and/or radiation therapy.

CASE REPORTS

Patient 1 presented with hydrocephalus and progressive lower extremity weakness, and was found to have a suprasellar mass as well as extensive spinal disease. Ventriculoperitoneal shunting, decompressive laminectomy with spinal tumor debulking, and chemotherapy with carboplatin and vincristine were initially employed. However, disease progressed and craniospinal irradiation and temozolomide were used. Patient 1 remains in a fair condition today, 2 years later. Patient 2 presented at 8 months of age with failure to thrive. Imaging revealed a cystic lesion in the hypothalamic region with extensive subarachnoid metastatic disease to the spine. Biopsy was performed followed by chemotherapy with vincristine, cyclohexylchloroethylnitrosourea (CCNU), 6-TG, and procarbazine. Due to the continued progression of the disease, cytoreductive surgery was performed and her chemotherapeutic regimen was switched to temozolomide. Two years after initial presentation patient 2 is clinically much improved with stable residual disease.

DISCUSSION

We review the literature and discuss treatment strategies for this challenging disease.

Leptomeningeal metastasis of primary central nervous system (CNS) neoplasms

Leptomeningeal dissemination of primary CNS tumors varies widely by histologic subtype. In certain tumors including medulloblastoma, ependymoma, germ cell tumors, and primary CNS lymphoma, seeding of the cerebrospinal fluid space is a critical factor in determining stage, prognosis and appropriate therapy. Other tumor types, such as glioma, may have radiographic evidence of leptomeningeal metastases without clear impact on prognosis or therapy.

Juvenile pilocytic astrocytoma `pilomyxoid variant' with spinal metastases

We report a case of juvenile pilocytic astrocytoma of the hypothalamic/chiasmatic region with cerebrospinal fluid dissemination in a 16-month old girl. The tumour in this case had unusual histological features including the abundance of myxoid background, the absence of Rosenthal fibres and the presence of an angiocentric pattern. These features are consistent with the recently described "variant" named pilomyxoid astrocytoma. It remains unclear whether pilomyxoid astrocytoma represents an aggressive variant of classical juvenile pilocytic astrocytoma, or an entirely distinct clinico-pathological entity. Larger series and new molecular techniques may answer this question in the future.

Leptomeningeal dissemination of pilocytic astrocytoma at diagnosis in childhood: two cases report

Pilocytic astrocytoma (PA) is a benign tumor that rarely spread along the neuraxis. At the moment there are no more than five cases of leptomeningeal dissemination (LD) from PA at diagnosis described in the literature. Different patterns of presentation or recurrence may be noted: local recurrence, malignant transformation, multicentric disease or metastatic disease. LD and multicentric disease can be distinct pathological entities. We report two cases and analyse literature, emphasizing leptomeningeal spread at presentation. Hydrocephalus, biopsy and parcial ressection are likely to be favorable factors to the occurrence of LD. Otherwise, LD may be part of natural history of PA, as evidenced by its ocurrence in non-treated cases.

Marked regression of metastatic pilocytic astrocytoma during treatment with imatinib mesylate (STI-571, Gleevec): a case report and laboratory investigation

Pilocytic astrocytomas are the most common childhood glioma. Most children with pilocytic astrocytomas survive many years with their tumor, but alternative treatment approaches are needed for those with refractory or metastatic disease. Signaling by the platelet-derived growth factor tyrosine kinase receptor pathways have been postulated to contribute to the development of gliomas. The authors treated a single patient with refractory, metastatic pilocytic astrocytoma with the tyrosine kinase inhibitor imatinib mesylate and observed marked, transient regression of tumor during treatment. Immunohistochemistry was used to assess expression of reported target genes of imatinib mesylate in this patient's tumor tissue and of the PDGFR in pilocytic astrocytomas from 19 other patients. Immunohistochemistry showed that the patient's tumor cells did not express any of the reported target molecules inhibited by imatinib mesylate. PDGFR expression was detected in tumor vasculative in the panel of 20 tumors, and not in the tumor cells. The authors suggest that the PDGFR-signaling pathway postulated to contribute to the development of gliomas in adults might not contribute to pilocytic astrocytomas in children, and that treatment with imatinib mesylate should be considered in patients with refractory pilocytic astrocytoma.

Low-grade gliomas and leptomeningeal dissemination: a poorly understood phenomenon

DISCUSSION

The leptomeningeal dissemination (LMD) of low-grade gliomas (LGGs) is reported in clinical neuro-oncology practice more and more frequently. It is estimated that 5% of all childhood LGGs present LMD at diagnosis and 7-10% at the time of progression. LMD has been reported in association with almost all the known subtypes of LGGs. Furthermore, "unusual " LGGs can be encountered among slow-growing brain neoplasm capable of LMD, which cannot comfortably be included in the present WHO brain tumour classification. The biological, genetic and clinical characteristics that seem to favour LMD are far from being understood. Similarly, the clinical profile of those children with disseminated LGGs has not yet been firmly established. Young, non-neurofibromatosis type 1 boys with large hypothalamic-chiasmatic pilocytic astrocytomas seem to be at increased risk of LMD. The neuroradiological appearance of LMD in childhood LGGs is similar to that observed in malignant tumours, except for those cases characterised by multiple superficial non-enhancing cystic lesions, which seem to be almost exclusively associated with a type of slow-growing not yet fully identified brain stem or spinal tumour. No firm guidelines for the treatment of these diseases are yet available, mostly due to the rarity of this condition and the existing uncertainties regarding their natural clinical history.

CONCLUSION

The evidence of LMD in children with LGGs does not seem to have a negative impact on patients' long-term outcome.

Multiple cystic brain lesions in a patient with pilocytic astrocytoma

Pilocytic astrocytomas are usually present as solitary posterior cranial fossa tumours. An unusual case of pilocytic astrocytoma in a 3 year and 8 month old boy is presented. The patient presented over the course of 10 months with intermittent headaches, vomiting, gait ataxia and drowsiness. After extensive investigations magnetic resonance imaging (MRI) revealed widespread lesions throughout the central nervous system, including multiple cystic cerebral grey matter lesions. A brain biopsy was performed and pathological studies revealed pilocytic astrocytoma. The literature pertaining to neuraxis dissemination of pilocytic astrocytomas in the paediatric population is reviewed. There are only a very limited number of reports of pilocytic astrocytoma ca using multiple brain lesions, with no publications of multiple cystic brain lesions. We believe this to be a unique case of pilocytic astrocytoma presenting with widespread cystic lesions throughout the brain.

Malignant pilocytic astrocytoma in the medulla oblongata: case report

A 27-year-old woman visited our hospital with chief complaints of abducens nerve palsy and cerebellar symptoms. On computerized tomographic scanning and magnetic resonance imaging, a tumor with strong enhancement was found on the dorsal side of the medulla oblongata. A tumor was excised by suboccipital craniotomy and C1 laminectomy. Histologically, many Rosenthal fibers together with pilocytic tumor cells were found in some regions, but a very high Ki-67 labeling rate accompanied by cells with nuclei of irregular size and giant cells was observed in other regions. The tumor was diagnosed as malignant pilocytic astrocytoma originating from pilocytic astrocytoma by transformation. The biological behavior of pilocytic astrocytoma is obscure in several respects. We report our experience of a case of malignant pilocytic astrocytoma that developed in the brain stem and progressed extremely rapidly.

Comparative genomic hybridization indicating two distinct subgroups of pilocytic astrocytomas

Object

The authors investigated the spectrum of chromosomal imbalances of pilocytic astrocytoma by using comparative genomic hybridization (CGH).

Methods

Tumor DNA was extracted from surgically obtained samples of 18 pilocytic astrocytomas that were examined for the presence of neoplastic tissue on frozen sections. Comparative genomic hybridization was performed using standard procedures, and digital image analysis was conducted using out by custom-made software. The chromosomal alterations were determined by a statistical procedure in which Student's t-test (99% confidence interval) was used. Details on CGH analysis and individual ratio profiles are available at http://amba.charite.de/cgh/.

Conclusions

The results suggests the presence of two distinct genetic subgroups of pilocytic astrocytoma, with imbalances of chromosome 19 being the major change for differentiation. In the first group (10 samples), deletions on chromosome 19 were shown as well as multiple gains mainly on chromosomes 5 and 6q but also on chromosomes 4, 7, 8, 10, and 11. The second group (eight samples) was characterized by overrepresentation on chromosomes 19p and 22q, which were associated with deletions on 4q, 5q, 6q, 9p, 13q, and 18q. To understand the diverse biological and clinical behavior exhibited by this tumor type, it is important that pilocytic astrocytomas be classified into distinct subgroups according to their genetic makeup.

Cyclin D1 and MIB-1 immunohistochemistry in pilocytic astrocytomas: a study of 48 cases

Pilocytic astrocytoma is an infrequently encountered, generally low-grade neoplasm. No study has extensively looked at both cyclin D1 and MIB-1 labeling indices in pilocytic astrocytoma and their relation to clinical outcome. This study retrospectively examines the clinicopathologic features of 48 patients with pilocytic astrocytoma including MIB-1 (cell proliferation marker) and cyclin D1 (protein that regulates progression from G1 to S phase of the cell cycle) immunohistochemistry. Of 48 patients (27 females and 21 males; mean age, 12.7 years; age range, 2 to 57 years), 26 initially underwent gross total resection; 17, subtotal resection; four, biopsy alone; in one patient, the extent of tumor resection was unknown. Histological features observed included Rosenthal fibers (83.3%), granular bodies (75%), vascular sclerosis (56.2%), vascular proliferation (56.2%), prominent nuclear pleomorphism (14.6%), necrosis (10.4%), and identifiable mitotic figures (2.1%). MIB-1 labeling indices (n=45) (positive staining tumor nuclei per 1,000 nuclei evaluated) ranged from 0 to 3.5% (mean, 0.6%); seven tumors had a labeling index greater than 1.0%. Cyclin D1 labeling indices (n=45) ranged from 0 to 0.8% (mean, 0.1%). Most tumors (N=29, 66.7%) had no immunostaining. At last known follow-up, 27 patients were alive with no evidence of disease (mean, 49.2 months), 17 patients were alive with evidence of disease (mean, 36.8 months), three died with tumor at 2, 22, and 156 months, and one patient was lost to follow-up. Eight patients had at least one tumor recurrence requiring additional surgery; seven of these patients had an initial subtotal resection. In summary, MIB-1 labeling indices were generally low (mean, 0.6%) and are reflective of the slow growth of the tumors. Cyclin D1 immunostaining does not appear to be significantly increased in pilocytic astrocytoma. Adverse outcome in patients with pilocytic astrocytoma may be related to extent of surgical resection and does not seem to correlate with histology, MIB-1 labeling indices, or cyclin D1 immunoreactivity.

Diffuse leptomeningeal gliomatosis associated with multifocal CNS infarcts

BACKGROUND

Widespread dissemination of astrocytoma throughout the cerebrospinal fluid is unusual, especially as the initial presentation in a patient, and association with cerebral infarcts is rare. CASE DESCRIPTION A 47-year-old man subacutely developed progressive headache and backache, vomiting, altered consciousness, and numbness in both arms. Brain computerized axial tomography showed calcification in the fourth ventricle and magnetic resonance imaging demonstrated diffuse meningeal enhancement, a lesion in the canal of Magendie, and T2-weighted hyperintense lesions in several locations. Angiography showed vasospasm/vasculopathy involving multiple cerebral vessels. Biopsy of the fourth ventricular mass revealed a subependymoma with an overlying leptomeningeal anaplastic astrocytoma with numerous Rosenthal fibers. The patient was treated with three doses of intrathecal methotrexate via lumbar puncture but suddenly became unresponsive and died 6 days later, 8 weeks after initial symptoms. Autopsy demonstrated the subependymoma and a widespread leptomeningeal anaplastic astrocytoma, which showed no clear-cut origin from the subependymoma, but microscopically infiltrated the left medial temporal lobe. Multiple subacute and acute infarcts of the brain, brain stem, and upper spinal cord were seen only in areas with leptomeningeal tumor. CONCLUSION Glioma cells surrounding and focally permeating central nervous system vessels without lumenal occlusion can lead to vasospasm and widespread infarcts.

Diencephalic syndrome and disseminated juvenile pilocytic astrocytomas of the hypothalamic-optic chiasm region

BACKGROUND

Diencephalic syndrome (DS) is a complex of signs and symptoms related to hypothalamic dysfunction; its main features are emaciation, despite a normal or slightly diminished caloric intake, and an alert appearance. DS has been almost exclusively described in association with space-occupying lesions of the hypothalamic-optic chiasm region, mainly juvenile pilocytic astrocytoma (JPA). A systematic diagnostic approach, including contrast-enhanced magnetic resonance imaging (MRI) of the child's head, is rapidly expanding our knowledge of this syndrome.

METHODS

The MRI findings for three children affected by DS associated with biopsy-proven JPA, consecutively referred to the Pediatric Neuro-Oncology Program of the Department of Pediatrics at the University of Padua between September 1991 and January 1996, are presented in this article. The children were boys, ages 6, 7, and 18 months, respectively.

RESULTS

In all three patients, the initial contrast-enhancing MRIs of the head showed evidence of tumor dissemination. This finding prompted a study of the spine, which in turn showed tumor deposits in all three subjects. Among the 43 patients younger than 16 years with low grade astroctyoma who consecutively entered the Neuro-Oncology Program during the study period, these 3 patients were the only ones who had disseminated tumors.

CONCLUSIONS

In this study, the hypothesis was formulated that DS and disseminated hypothalamic-optic chiasm JPA tend to be more commonly associated than previously stated. This study suggests that the initial contrast-enhanced MRI of the head of a child affected by DS and hypothalamic JPA must be looked at carefully for evidence of tumor dissemination, and that the spine must also be examined if the findings are positive.

Recurrent cerebellar gliomas: salvage therapy with oral etoposide

The purpose of this investigation was to assess the toxicity and activity of chronic oral etoposide in the management of children with recurrent juvenile pilocytic cerebellar astrocytomas. Twelve children with recurrent juvenile pilocytic cerebellar astrocytomas, refractory to surgical resection, radiotherapy, and chemotherapy were treated with chronic oral etoposide. Treatment related complications included alopecia, diarrhea, weight loss, and thrombocytopenia. Three children required transfusion and one child developed neutropenic fever. No treatment related deaths occurred. Six children demonstrated either a radiographic response or stable disease with a median duration of 7 months. Oral etoposide was well tolerated, produced modest toxicity, and had apparent activity in this small cohort of children with recurrent juvenile pilocytic cerebellar astrocytomas.

Successful treatment of childhood pilocytic astrocytomas metastatic to the leptomeninges with high-dose cyclophosphamide

Leptomeningeal dissemination of childhood pilocytic astrocytoma (PA) is a rare event with little information available regarding therapy. We report here four children with disseminated PA whom we treated with high doses of cyclophosphamide with clinical benefit. The patients were aged 2.5 to 8 years. Three patients presented with PA localized in the posterior fossa, initially treated with surgical resection (n = 3) and radiotherapy (n = 1). Leptomeningeal dissemination occurred at 32, 44, and 8 months from diagnosis, respectively. The fourth patient presented with an optic pathway tumor with leptomeningeal dissemination at diagnosis. At commencement of cyclophosphamide therapy, disease was present in the subarachnoid space (intracranial, n = 2; spinal, n = 4), cerebral ventricles (n = 2), and primary site (n = 3). Histology was identical at diagnosis and recurrence in the two biopsied cases and cerebrospinal fluid was negative in all cases. Treatment was with cyclophosphamide 4-5 g/m2/cycle given every 4 weeks for a total of two cycles (n = 1) and four cycles (n = 3). One patient achieved disease stabilization (duration 27 months at the time of publication) and three patients experienced significant reductions in tumor burden. Subsequent intrathecal therapy was administered to two patients. Two patients developed disease progression at 10 and 9 months from cessation of chemotherapy. The one re-treated patient responded to further, lower dose, cyclophosphamide. This is the first report of the use of high dose cyclophosphamide for disseminated PA. The recurrence of disease in two cases with a further response to lower dose cyclophosphamide has implications for the optimal duration of therapy for these low grade, aggressive tumors.

Chemotherapy for progressive pilocytic astrocytomas in the chiasmo-hypothalamic regions

Over the past 25 years, we have treated 17 patients with chiasmo-hypothalamic astrocytomas. Before 1988, the initial treatments consisted of surgery and/or radiotherapy, while since 1989, 4 children (1 male, 3 females, aged 3-8 years) were treated primarily with chemotherapy. None of them was associated with neurofibromatosis. After a biopsy of the tumor, the intravenous administration of ranimustine (MCNU; 30-86 mg/m2) and/or nimustine (ACNU; 30.3-64.1 mg/m2) was given without radiation therapy. Chemotherapy was usually given as an out-patient, with a total of 5-13 courses. The total doses of MCNU and ACNU administered ranged from 150 to 570 mg and from 64.8 mg to 100 mg, respectively. After chemotherapy 2 patients showed clinical improvement and tumor regression on neuro-imaging, while one patient showed clinical improvement and tumor size stabilization on neuro-imaging. The remaining one child, however, showed a clinical worsening and tumor progression on neuro-imaging studies. He was thus treated with a second chemotherapy regimen with carboplatin and etoposide, which brought about tumor regression. The acute and subacute toxicity of chemotherapy was mild. All patients are now leading almost normal lives with a median of 43 months after diagnosis. Although a longer and more careful clinical observation is required, the authors conclude that chemotherapy with MCNU and/or ACNU may benefit patients with unresectable pilocytic astrocytoma requiring treatment. The advantages of this therapy include its mild side effects and the lack of any hospitalization in most patients. It may also delay the need for radiation therapy, which can have a deleterious effect on the young developing brain.

Low-grade astrocytoma with neuraxis dissemination at diagnosis

Little is known about low-grade astrocytoma with neuraxis dissemination at diagnosis. A review of medical records identified this phenomenon in eight of 150 pediatric patients evaluated between 1985 and 1994 for histologically confirmed low-grade astrocytoma. These patients (five male and three female) ranged in age from 5 months to 20 years (median 8 years). Symptoms of neuraxis disease were minimal or absent. Primary tumor sites were the hypothalamus in four cases, brainstem/spinal cord in three, and temporal lobe in one. Patterns of dissemination (evaluated by computerized tomography and/or magnetic resonance imaging techniques) appeared to be related to the primary site: hypothalamic tumors metastasized along the ventricular cerebrospinal fluid pathways, and tumors in other locations disseminated along subarachnoid pathways. Following initial treatment with chemotherapy (in three), partial resection (in one), radiation therapy (in three), and chemotherapy plus irradiation (in one), four patients required salvage therapy for progressive or recurrent disease. Seven of the eight patients are alive with stable or progressive disease 6 to 105 months postdiagnosis (median 15 months). Low-grade astrocytoma with initial neuraxis dissemination is responsive to chemotherapy and radiation, a proportion showing periods of stable disease. The optimum therapy or combination of therapies remains unclear.

Deletion of chromosome arm 17p DNA sequences in pediatric high-grade and juvenile pilocytic astrocytomas

In adults, loss of heterozygosity for DNA on 17p has been shown in high-grade anaplastic astrocytomas (AAs) and glioblastomas multiforme (GMs), and mutation of the TP53 tumor suppressor gene has been reported in all grades of astrocytomas. Little is known, however, about 17p deletion and TP53 mutation in juvenile pilocytic astrocytomas (JPAs), the most common low-grade tumors seen in children. To elucidate the genetic characteristics of pediatric high-grade astrocytomas and JPAs, we performed restriction fragment length polymorphism analysis with probes derived from 17p and TP53 mutational studies in 28 tumor specimens. Telomeric chromosome arm 17p markers 144-D6 and ABR were lost in 6 (75%) of 8 informative tumors classified as high-grade (7 AAs, 1 GM) and in 2 (10%) of 20 informative JPAs. Loss of 17p probes centromeric to the TP53 gene were also detected in 3 AAs and 5 JPAs. Four of the 6 (66%) JPAs with losses of 17p DNA sequences recurred rapidly despite aggressive therapy, whereas only 5 of the other 14 (36%) recurred. Mutation of the TP53 gene was detected by polymerase chain reaction and denaturing gradient gel electrophoresis in only 1 JPA and 1 AA. These tumors were also examined for MDM2 gene amplification as an alternate inactivation mechanism for TP53 gene function: no instances of alteration were identified. These results suggest that a gene or genes in addition to TP53 on 17p may be involved in the etiology or progression of high-grade astrocytomas and aggressive JPAs in children.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment options and prognosis for multicentric juvenile pilocytic astrocytoma

Little is known about the risk of developing multicentric disease in patients with juvenile pilocytic astrocytoma (JPA), and even less about its prognosis. Only five cases have been reported. Between 1986 and 1992, the authors treated 90 patients with either primary or recurrent JPA, 11 of whom developed multicentric spread. Ten patients had primary tumors in the hypothalamic region, eight were under 4 years of age at initial diagnosis, all had initially undergone a subtotal resection or biopsy, and 10 received postoperative multiagent chemotherapy or irradiation for residual disease. Multicentric spread was discovered immediately to 108 months after initial diagnosis; nine patients were asymptomatic at the time. Most patients received chemotherapy for the multicentric disease, which was found throughout the craniospinal axis. During 21 to 148 months of follow-up monitoring, seven patients had stabilization or regression of multicentric disease and four died. Patients with hypothalamic region tumors were 23 times more likely to develop multicentric spread than were those with primary tumors located elsewhere (p < 0.001). Based on this review, it is concluded that multicentric spread of JPA occurs more frequently than was previously recognized. In patients with subtotally resected JPA and several years of follow-up review via magnetic resonance imaging, the incidence of recurrence in a site different from the original was 12%. Patients with subtotally resected JPA in the hypothalamic region should be considered to be at high risk for developing multicentric spread. Chemotherapy appears useful in stabilizing multicentric disease. Earlier detection and intervention may result in longer disease-free survival in patients with multicentric spread of JPA.

Dissemination of low grade intracranial astrocytomas in children

The authors report three cases of histologically benign intracranial astrocytomas that developed in children and disseminated within the neuraxis. Multicentric disease was evident at the time of diagnosis in two of these patients, one of whom subsequently developed peritoneal seeding of tumor after placement of a ventriculoperitoneal shunt. To our knowledge, this latter represents the first documented case of extraneural seeding of a benign astrocytoma. All three children are currently alive and well 17-117 months after the diagnosis of tumor dissemination. We review the literature regarding this uncommon problem and discuss the pathophysiology and treatment options. Our results indicate that the presence of disseminated disease may not preclude long term survival, provided the lesions are truly benign histologically and that adjuvant therapy is instituted promptly.

Leptomeningeal dissemination of malignant gliomas. Incidence, diagnosis and outcome

To understand the clinicopathology features of leptomeningeal dissemination of malignant gliomas, a total of 157 consecutive patients treated between 1978 and 1989 were analysed. Twenty-two patients (14%) were judged to have dissemination. In 20 patients, the dissemination was diagnosed antemortem. Eleven patients had neurological deficits due to dissemination, whereas the other 9 without these had CT or myelographic evidence of dissemination. The peak incidence of dissemination was seen in the first and second decades of life. The mean age of 22 patients with dissemination was 31 years, significantly lower than that (44.5 years) of patients without dissemination. Fifteen patients developed dissemination within one year after diagnosis (early dissemination), 60% of them were less than 30 years of age. All patients with late dissemination (more than one year after diagnosis) underwent a second craniotomy for tumour removal before dissemination, while none of the 15 patients with early dissemination did. Survival after diagnosis in patients with dissemination was shorter, although statistically not significant, than that of patients without dissemination. Survival after dissemination was limited in all patients (mean 19 weeks, range 2-39 weeks). Immunohistochemical study revealed that the disseminated tumour expressed less glial fibrillary acidic protein than the primary tumour. Our results suggest that dissemination does not seem to result from extended survival of the patients, but may occur at any time in malignant gliomas. Some malignant gliomas, especially in younger patients, have a capability to acquire biological characteristics suitable for dissemination in the earlier stage of the disease.

Neoplastic meningitis as the presentation of occult primitive neuroectodermal tumors

Seven children and young adults initially presented with subacute meningitis and/or increased intracranial pressure. The diagnosis of neoplastic meningitis secondary to a primitive neuroectodermal neoplasm was delayed by the absence of an obvious primary tumor. The neuroradiologic appearance was that of a basimeningeal infiltrative process, complicated by communicating hydrocephalus or "pseudotumor cerebri." Myelography was important in the diagnosis of disseminated meningeal malignancy in four cases. Cerebrospinal fluid cytologic diagnosis was insensitive but ultimately confirmed in five cases. All seven patients experienced progressive disease despite neuraxis radiotherapy and intensive chemotherapy; six have died. Systemic dissemination to bone and/or peritoneum occurred in three patients while on therapy. In two, a primary parenchymal brain or spinal cord tumor could not be identified at postmortem examination. The presentation of a primitive neuroectodermal tumor as subacute meningitis without an evident primary tumor heralds an aggressive and refractory neoplasm.