THE DEVELOPMENT OF BRAIN TUMOURS PRODUCED IN RATS BY THE INTRACEREBRAL INJECTION OF NEOPLASTIC GLIAL CELLS: A FINE STRUCTURAL STUDY*

Davaki P. & Lantos P.L. (1981) Neuropathology and Applied Neurobiology 7,49–61 The development of brain tumours produced in rats by the intracerebral injection of neoplastic glial cells: a fine structural study Tumours were produced by the intracerebral injection of a clone of glial cells derived from a glioma induced transplacentally by N-ethyl-N-nitrosourea in a BD-IX rat. The injection of 5 times 10⁵ cells into the left frontal lobe resulted in a 100% incidence of tumours. To follow the development of the neoplasms, the brains were studied from 1 day to 4 weeks after injection. The tumours maintained their glial characters throughout, but their features changed with time. Ultrastructurally, they were pleomorphic: the proportion of fibrillary astrocytes, undifferentiated and intermediate cell types varied according to tumour size. When smaller (1 and 2 weeks), fibrillary astrocytes predominated, but when larger (3 and 4 weeks), the number of undifferentiated astrocytes considerably increased. A reproducible brain tumour model with a short latency has thus been established and characterized, which may be of use for chemo- and radiotherapeutic studies and for examining the mechanisms of cerebral oedema.     

A SURVEY OF ETHYLNITROSOUREA-INDUCED RAT GLIOMAS FOR THE PRESENCE OF TUMOUR REJECTION ANTIGENS EXPRESSED IN VIVO

Spence A.M. & Priestley G. (1981) Neuropathology and Applied Neurobiology 7,63–75.
A survey of ethylnitrosourea-induced rat gliomas for the presence of tumour rejection antigens expressed in vivo
Transplanted lines of seven F-344 (Fischer) rat malignant gliomas induced transplacentally with ethylnitrosourea (ENU) were surveyed by in vivo im-munoprotection assays for the presence of tumour rejection antigens. These gliomas were representative of commonplace histological types of human primary brain tumours and were analyzed in early transplantation passages. The classical tumour ligation method of immunizing animals was attempted with five glioma lines, but was found unusable in four of these because of a high incidence of local tumour recurrences and distant metastases. In most experiments the animals were immunized by repeated inoculations of heavily-irradiated tumour cells. Two gliomas, a glioblastoma multiforme and a mixed astrocytoma-ependymoma, demonstrated weak but statistically significant tumour rejection responses. Immunization with three other tumours, a mixed oligodendroglioma-astrocytoma and two glioblastomas multiforme, led to enhanced outgrowth of the challenge cell inocula. Neither a rejection nor an enhancement response was observed in assays of the remaining two neoplasms, a glioblastoma multiforme and a mixed astrocytoma-oligodendroglioma. Immunization with a 3-methylcholanthrene-induced urinary bladder carcinoma line, used as a control in assays of six gliomas, had no effect on the outgrowth of transplanted glioma cells. These results suggest that ENU-induced malignant rat gliomas do not uniformly elicit strong tumour-rejection responses in vivo.     

Diagnosis of brain gliomas in stereotactic biopsy assisted by optical neuro-navigation system

BACKGROUND AND PURPOSE: Recently, stereotactic procedures of brain tumours have been enriched by an optical neuronavigation system, enabling us to assess the tumour location and size by means of three-dimensional magnetic resonance imaging (MRI). The aim of the study was to check which areas of brain gliomas would be most useful in neuropathological diagnosis of the material taken during stereotactic biopsy. We also analysed whether the MRI processed in the computerised neuronavigation system would be reliable in determination of a safety margin of glioma resection. MATERIAL AND METHODS: Material from the stereotactic biopsy has been examined neuropathologically by means of the Stealth Station navigation system. Tissue specimens were taken from the centre of neoplasm, its intermediate area, edge of the tumour and the nearest vicinity of neoplasm. 2-3 specimens in each area of the tumour were taken. The material was fixed in buffered formalin and embedded in paraffin and then stained with hematoxylin and immunostained for GFAP, cytokeratin and vimentin. RESULTS: Astrocytomas II were diagnosed in 17 cases, including fibrillary astrocytoma in 13 cases and gemistocytic astrocytoma in 2 cases. In other cases protoplasmatic astrocytomas were suspected. In 6 cases anaplastic astrocytoma and in 16 cases glioblastoma multiforme were diagnosed. In 3 cases the degree of malignancy was not possible to be defined. In 2 cases the neoplasm was not found. "Sensitivity" of the method was 91.1% and its "specificity" was 82.2%. The best results were achieved analysing the material from the intermediate area of neoplasm. There was the lowest number of "false negative" diagnostic results in this area. A few positive results were found in the central area and a high number of results (almost 50%) could be defined as "negative", assuming the specimens with no neoplastic cells. In more than 40% of biopsies from the edge of the tumour, neoplasm was not found, while in more than 20% of biopsies from the nearest vicinity of the tumour, neoplastic cells were present. CONCLUSIONS: Intermediate zone of brain gliomas located between its central parts and the tumour edge appears to be the most appropriate neoplastic area for diagnostic stereotactic biopsy assisted by the optical neuronavigation system. Because of infiltrative character of brain gliomas as well as their real dislocation during surgical procedure compared to the position based on the earlier neuroimaging, the territories considered in the optical neuronavigation system as the vicinity or neoplastic edge, run a risk of neuropathological misdiagnosis in this biopsy.     

DEMONSTRATION OF A COMPLEMENT INACTIVATOR ON CULTURED CELLS FROM HUMAN MALIGNANT BRAIN TUMOURS

Human primary and secondary malignant, and primary benign brain tumours were short time cultured in order to detect a coating with a protein, immunologically indistinguishable from complement component Cl inactivator. The investigations were done by cytophotometry of immunoflurescence on individual cells from human brains. The cell cultures were incubated with specific rabbit antiserum against human Cl inactivator, conjugated with fluorescein isothiocyanate. The majority of the malignant brain tumours, and a few of the benign brain tumours, were shown to carry the Cl inactivator—resembling protein. The primary malignant brain tumour cells seemed to lose this coating during prolonged culturing. Metastatic brain carcinomas retained their inactivator coating.     

Secreted protein,acidic and rich in cysteine (SPARC) expression in astrocytic tumour cells negatively correlates with proliferation,while vascular SPARC expression is associated with patient survival

D. Capper, M. Mittelbronn, B. Goeppert, R. Meyermann and J. Schittenhelm (2010) Neuropathology and Applied Neurobiology 36, 183–197
Secreted protein, acidic and rich in cysteine (SPARC) expression in astrocytic tumour cells negatively correlates with proliferation, while vascular SPARC expression is associated with patient survival Aims: Secreted protein, acidic and rich in cysteine (SPARC) is a regulator of cell–matrix interaction and has been associated with tumour stage and patient survival in various malignancies. As no large‐scale study has yet been undertaken, we investigated human brain and astrocytomas for SPARC expression and associations with tumour grade, proliferation, vascular density and patient survival. Methods: A spectrum of 188 WHO grade I–IV astrocytic tumours and 24 autopsy cases were studied by immunohistochemistry for SPARC, MIB‐1 proliferation index and CD31‐positive vessels. SPARC protein expression was confirmed by quantitative real‐time polymerase chain reaction and Western blot in 13 cases. Results: In normal brain, SPARC is expressed in cortical marginal glia, cerebellar Bergmann glia and focally in white matter but is absent in neurones or vessels. High SPARC expression levels in the cytoplasm of astrocytic tumour cells decreased with the grade of malignancy but showed an increase with grade of malignancy in tumour vessels. SPARC negatively correlated with tumour proliferation but not with vascular density. While cytoplasmic SPARC staining was not associated with survival, vascular SPARC showed a significant association in the group of grade II–IV tumours (P = 0.02) and also in grade II astrocytomas alone (P = 0.01) with vascular SPARC associated with worse prognosis. Conclusions: SPARC is highly expressed in astrocytomas and decreases with tumour progression. We confirm an association of increased SPARC expression and decreased proliferation. While there is no association between the level of SPARC in the tumour cells and patient survival, increased tumour vascular SPARC expression is associated with decreased patient survival.     

rCBF in brain tumours as measured by xenon enhanced CT

Heretofore, the rCBF of brain tumours has been measured by the 133Xe clearance method, but the resolving power of this method is limited and flow values measured by this method correlate poorly with the anatomical structure. On the other hand, our xenon-enhanced method has several advantages over the conventional isotope method and enables us to evaluate rCBF with a resolving power of 4 mm. With this method, we evaluated rCBF in 15 brain tumour cases and obtained the following results: Mean rCBF value of the tumour is a little lower than that of grey matter and higher than that of white matter with oedematous change. The xenon-enhanced method enables us to distinguish the demarcation between the tumour area and the surrounding oedematous area and offers useful information for determining the extent of resection in surgery. Mean lambda value of the tumour which is not obtainable in vivo by radionuclide scanning, was 1.02 +/- 0.06 for gliomas and 0.72 +/- 0.09 for metastatic tumours.     

A second brain tumour and irradiation.

Three patients are described in whom irradiation of 2750 rad or more was used in the management of primary brain tumours, and 21 years or more later a second brain tumour of a different type occurred. One of the new tumours was a meningioma and the other two were cerebral astrocytomas. There is evidence to show that moderate doses of ionising radiations given in childhood for tinea capitis are associated with a late risk of developing a meningioma. Higher doses of radiation used for tumours in childhood are followed also by a late hazard of meningioma. There is insufficient evidence to implicate ionising radiations in the aetiology of gliomas. The oncogenic hazards of radiotherapy to the brain do not outweigh its therapeutic value in brain tumour.     

Functional rehabilitation and brain tumour patients. A review of outcome

Abstract The increasing prevalence of brain tumours and longer duration of survival achieved by recent advances in treatment prompt a critical analysis of the impact of functional rehabilitation on patients with brain tumours. In this review brain tumours and outcome of brain tumour patients are discussed from a rehabilitation perspective, taking into account not only life expectancy but also the direct and indirect causes of functional impairment. Results of functional rehabilitation and factors involved in its effectiveness are presented and analysed to serve as a basis to neurologists involved in the management of patients with brain tumours.     

Vascular endothelial growth factor expression in cerebral neoplasms

Angiogenesis plays an important role in growth of neoplasm. Among a variety of proangiogenic agents, vascular endothelial growth factor (VEGF) is regarded as a crucial mediator of tumour angiogenesis. It acts in a paracrine way through the receptors localised in endothelial cells. Many authors maintain that rich vasculature of the neoplasm is associated with its malignant nature. The aim of this study was to examine the relations between expression of VEGF and features of malignancy of brain tumours. Sixty-seven samples of brain tumours were examined: 17 meningiomas, 34 gliomas and 16 metastases to the central nervous system. Expression of VEGF was estimated by radioimmune assay. The authors confirmed the presence of this factor in all types of tumours but the highest concentration of VEGF was found in high-grade gliomas.     

Tumour vascularity is of prognostic significance in adult, but not paediatric astrocytomas

Astrocytomas are the commonest type of brain tumours in adults and children. Although the most reliable prognostic indicators have been shown consistently to be patient age and tumour histological grade, biological progression in these tumours is inevitable and the overall prognosis has remained poor. Due to the evidence that vascular changes are important histological features of astrocytomas, the aim of this study was to investigate prognostic significance of tumour vascularity in paediatric and adult astrocytomas. Study population consisted of 70 patients (45 adult and 25 children) with histologically proven diagnosis of astrocytoma with no history of previous therapy. Histological quantification of tumour vascularity was performed using three different methods: microvessel density, vascular grading and Chalkley counting. Histological classification and grading were also assessed using the World Health Organization system. In contrast to the results in paediatric astrocytomas, tumour vascularity in adult tumours correlated significantly with postoperative survival by univariate analysis (P < 0.05). Microvessel density appeared to be an independent indicator of prognosis by multivariate analysis (P = 0.001). Likewise, patients with microvessel density of 70 or greater had significantly shorter survival than the remaining group (P < 0.001). Patient age and tumour histological grade were also correlated with survival. We conclude that histological quantification of tumour vascularity is a significant prognosticator in adult astrocytomas, but not in children. Our data do not support the validity of applications of antiangiogenic agents in paediatric astrocytic tumours, particularly pilocytic astrocytomas.     

The vasculature of experimental brain tumours: Part 2. A quantitative assessment of morphological abnormalities

Two groups of the morphological abnormalities of brain tumour vasculature described in the previous paper (Deane and Lantos 1981) were quantified. First, blood vessel density, endothelial hyperplasia and endothelial cytology, 3 general features of the vasculature, were assessed, giving a score according to the Microscopic Angiogenesis Grading System (Brem et al. 1972). This not only gives information about the vascular supply of tumours but also often provides a reliable index of malignancy. The system was also adapted for electron microscopy. Secondly, 3 specific features of the endothelial lining were estimated: cytoplasmic vesicle content, fenestrations and abnormal endothelial intercellular junctions, which are thought to represent possible mechanisms of increased trans-endothelial transport. It was found that cytoplasmic vesicle content was 3–6-fold greater in tumour blood vessels than in capillaries from normal brain, and may therefore play an important role in cerebral oedema. However, fenestrations and abnormal endothelial junctions were infrequently seen, and were unevenly distributed.     

A report of nine newborns with congenital brain tumours

Background Although rare, brain tumours represent one of the relatively larger groups of congenital neoplasias. Most studies on congenital neoplastic disease deal with several types of neoplasms and are dominated by leukaemias, retinoblastomas and systemic solid tumours. Few studies are dedicated to congenital brain tumours. We present nine newborns (four boys and five girls) who were diagnosed with congenital brain tumours during the 8-year period 1 January 1992–31 December 1999 at our institution, which covers all paediatric neuro-oncology cases for Eastern Denmark.Epidemiology Two of the cases were referred from Western Denmark for surgery, and were therefore excluded from the calculation of incidence. During the same period, a total of 172 children below the age of 15 years were diagnosed as having primary central nervous system tumours. The seven remaining congenital cases thus represent 4% of all paediatric brain tumour cases in the area (95% confidence interval 1.7–8.3%). The population of the referral area is 2.383×10⁶, and based on the total number of living births, the incidence of congenital brain tumour was calculated to be 2.9 per 100,000 live births. The ages of the mothers were 28–33 years, corresponding to the present mean age of 31 years for Danish primipara. The gestational age varied between 35 and 42 weeks, and the birth weights were 3,044–4,790 g.Risk factors Two patients with p53-related glioblastoma multiforme (GBM) had relatives with p53-related neoplasms. In one case, the mother was treated for cancer of the ovary with surgery and chemotherapy 2 months before conception.Clinical features In five of the cases, brain abnormality was suspected antenatally. The clinical features of the newborns were limited to enlarged head circumferences, associated hydrocephalus, and asymmetric skull growth.Diagnosis and treatment Three babies were treated with complete tumour resection. In the remaining six cases, a guided or open biopsy to obtain histology was made after CT/MRI imaging. The histological diagnoses were teratoma in four cases, GBM in two cases, anaplastic astrocytoma in two cases and, finally, haemangioma capillare in one case.Outcome Four of the patients (44%) are still alive, including two patients with totally resected combined orbital/intracranial teratomas, one patient with a totally resected haemangioma and one patient with anaplastic astrocytoma who did not receive any treatment apart from supportive care. The survival lengths of the five neonates who died varied between 1 day and 51 days.A commentary on this paper is available at .     

Advances in magnetic resonance imaging of brain tumours

PURPOSE OF REVIEW: Magnetic resonance imaging (MRI) of brain tumours provides excellent anatomical detail of brain tumours and can also reveal the biology, cellular structure and vascular dynamics of a tumour, although the use of such features in routine clinical practice has yet to be realized. In this review the latest advances in MRI of brain tumours are discussed and their clinical applications highlighted. RECENT FINDINGS: A large international study is underway to develop more powerful methods for automated classification of MR spectra based on the acquisition of large datasets of tumour spectra. Diffusion weighted imaging can help in the distinction between gliomas and abscesses, and perfusion weighted imaging can predict response to radiotherapy in low grade gliomas as well as distinguishing between different types of cerebral metastases. Intraoperative MRI has now been shown to be technically feasible, safe and effective in obtaining histological information as well as increasing the likelihood of complete resection for pituitary tumours and gliomas. Functional MRI and magnetic source imaging are alternative modalities that help the surgeon to avoid eloquent brain areas but may occasionally provide misleading information. Diffusion tensor imaging can demonstrate the effect of a tumour on white matter tracts and provides complementary information to that from other techniques that reveal areas of eloquent cortex. SUMMARY: Advances in MRI techniques are providing better diagnostic and therapeutic information, but can only ever be a surrogate marker of physiological and pathological processes; until it can routinely be used to image the brain at a cellular level, MRI will always be secondary to pathology in the final diagnostic evaluation.     

Scintigraphic assessment of vascularity and blood-tissue barrier of human brain tumours.

Assessment of vascularity and blood-tissue barrier was performed by sequential scintigraphy in 43 patients with brain tumours. The blood-tumour barrier was evaluated by use of 99mTc-pertechnetate, and vascularity using 99mTc-labelled red blood cells. Three groups of tumours were found: tumours with low vascularity and permeable barrier, tumours with high vascularity and permeable barrier, and tumours with low vascularity and relatively impermeable barrier. The first group indicates that when vessels are permeable, there may be a rapid penetration of large amounts of pertechnetate into the tumour even when vascularity is not increased. In the other two groups penetration of pertechnetate into the tumour is affected by vascularity, as it determines the total area where passage of the radiopharmaceutical takes place. It is suggested that the permeability of the blood-tumour barrier and the amount of vascularity may have an effect on the success of chemotherapy in brain tumours.     

Meningiomas of the lateral ventricles of the brain in children

Meningiomas of the lateral ventricles of the brain are rare tumours, accounting for approximately 0.5–5% of all intracranial meningiomas. Their natural history and symptomatology and the possibilities of early diagnosis are presented. The intraventricular location of the slow-growing benign mass provides a compensatory mechanism in the form of reserve space, which contributes to the delay in clinical demonstration of symptoms and signs. This makes the choice of diagnostic procedure an essential problem. CT and MRI are useful in detecting these masses, and magnetic resonance angiography (MRA) has also proved to be of great value in demonstrating the vascular supply of the tumour. This paper deals with two cases. In case 1 CT, MRI and MRA and in case 2 CT examination proved to be very useful. The tumours were removed by a transcortical approach in the posterior area. Received: 15 January 1998     

Ultrastructure of glioma vessel--morphometric study for vascular permeability

In this study we investigated the ultrastructure of human glioma capillaries in operated sample of low grade astrocytomas and malignant gliomas. Electronmicrographs of a total of 58 vessels were analyzed with computer assisted morphometry for ultrastructural evidence of permeability routes. All of these vessels were present in the marginal area of tumors devoid of necrosis, less than 10 micron in diameter and containing one nucleus at least on axial section. We found that: (1) The number of pinocytic vesicles was significantly higher in capillaries from malignant glioma (an average of 8.1 per 1 micron (2) cytoplasm) than those from low grade astrocytoma (an average of 4.0 per 1 micron (2) cytoplasm). In capillaries from malignant glioma, most of the pinocytic vesicles were arranged in the abluminal side of endothelium and some of them were fused each other. (2) Abnormal endothelial intercellular junctions which were defined as short tight junctions (less than or equal to 0.25 microns) were equally but infrequently seen in low grade astrocytomas and malignant gliomas. (3) Fenestrations in the endothelium were not seen. Therefore we suggest that the high vascular permeability and resultant brain edema in malignant gliomas is likely to increased pinocytic vesicles and rare but abnormal inter endothelial junctions.     

Spontaneous haemorrhage into metastatic brain tumours after stereotactic radiosurgery using a linear accelerator

OBJECTIVE: To determine the incidence and clinical characteristics of spontaneous haemorrhage into metastatic brain tumours after radiosurgery. METHODS: Intratumour haemorrhage rate, clinical features, and treatment were evaluated in 54 patients with 131 brain metastases of varying origin who were treated using linear accelerator radiosurgery. The marginal dose was maintained constant at 20 or 25 Gy, irrespective of tumour size. RESULTS: Haemorrhage was identified in 7.4% of the metastases (five tumours in four patients) before radiosurgery and in 18.5% (10 tumours in 10 patients) after radiosurgery. In three cases, haemorrhage into the tumour after radiosurgery was symptomatic. Half the haemorrhages occurred within one month of radiosurgery. The changes in tumour size observed at the time of haemorrhage were an increase in one tumour, no change in five, and a decrease in four. Haemorrhage into a tumour after radiosurgery was more likely to occur in female patients, in tumours with a larger volume on pretreatment neuroimaging, and in tumours treated with a larger number of isocentres or a higher maximum dose. Haemorrhagic features in the patients or their tumours on presurgical assessment were not disposing factors to haemorrhage after radiosurgery. CONCLUSIONS: When larger brain metastases are aggressively treated by radiosurgery, better local control may be attained but there may also be a higher risk of haemorrhage soon after the treatment.     

Incidence of brain tumours in two English counties: a population based study

OBJECTIVE: To define the incidence of brain tumours in Devon and Cornwall and to discover which case finding methods are the most fruitful. To examine what happens to patients after the diagnosis of a brain tumour. METHODS: The primary method of case ascertainment was a review of all CT with contrast and MRI of the head performed on the population of Devon and Cornwall between 1 April 1992 and 31 March 1997. Secondary sources included registrations with the South and West Cancer Intelligence Unit and a search for all patients either admitted to hospital with a brain tumour or operated on for a brain tumour during the same period. RESULTS: 16,923 scans were reviewed of which 8774 (52%) were normal. The scan review found 2483 incident intracranial tumours, of which 861 were metastases. Secondary sources of case ascertainment disclosed 46 further cases. Cases were missed by the scan review mainly for technical reasons and only three patients were found who were diagnosed by non-imaging methods. The incidence of primary intracranial tumours standardised to the population of England and Wales was higher than any previously reported (21.04 (17.18-25.62)/100,000 person-years). Overall, 21% of cases were not admitted to hospital. The categories least likely to be admitted were those with sellar and cranial nerve tumours. Those not admitted to hospital were significantly older than those who were. CONCLUSION: One fifth of patients are not admitted to hospital after the diagnosis of a brain tumour and incidence studies must use case finding methods which will capture these cases. An audit of imaging results provides almost complete case ascertainment. This study shows that the incidence of primary brain tumours is considerably higher than previously thought. Official figures from the cancer intelligence units significantly underestimate brain tumour incidence, especially for benign tumours.     

The vasculature of experimental brain tumours: Part 1. A sequential light and electron microscope study of angiogenesis

The process of vascularisation was studied in transplanted astrocytomas in BD-IX rats. The development of blood vessels was followed from the earliest signs of angiogenesis throughout tumour growth.On the basis of tumour vasculature, 3 consecutive stages of tumour growth could be distinguished; avascular, early vascular and late vascular. The tumours grew to a diameter of about 1 mm during the avascular stage after which new capillary sprouts began to penetrate the tumours. This resulted in an homogeneous vasculature of small immature capillaries up to about 5 μm in diameter characteristic of the early vascular growth stage. During this stage the tumours reached a diameter of about 4 mm and their vasculature consisted of capillaries similar to those seen in embryological cerebral vascularisation. During the subsequent late vascular stage of growth, continued endothelial proliferation led to an increase in blood vessel diameter up to 40 μm in some cases. The vessels varied in shape and size; this vascular pleomorphism and the abnormal morphological features associated with glioma vasculature were typical of the late vascular stage.     

Intraoperative swelling leading to neurological deterioration: An argument for large craniotomy in awake surgery for glioma resection

Gliomas are intrinsic brain tumours that are frequently associated with cerebral oedema. As such, keyhole approaches may not be appropriate because if the craniotomy is small, intraoperative cerebral oedema may occur, resulting in cortical compression at the bone edge. This would lead to further neurological deficit, especially if the swollen brain is located in eloquent areas. In awake craniotomy, worsening of such a deficit would mandate premature cessation of surgery and lead to a less than ideal extent of resection. Two such cases of intraoperative brain swelling are described to illustrate this point. The authors suggest doing a larger craniotomy for glioma patients undergoing awake surgery to prevent compression of normal brain at the craniotomy edge and to allow for a more complete resection by providing access to the tumour even if intraoperative swelling does occur.