Cerebral atypical teratoid/rhabdoid tumor of infancy: long-term survival after multimodal treatment, also including triple intrathecal chemotherapy and gamma knife radiosurgery--case report

Cerebral atypical teratoid/rhabdoid tumors (AT/RT) of infancy are highly malignant and have a poor prognosis. The authors report on one case with long-term survival. The patient was a 1 year-old boy presenting with a large AT/RT in the right temporal lobe. He was treated with complete surgery, followed by multiagent chemotherapy. Later he had a second resection and intrathecal chemotherapy and Gamma knife radiosurgery was added to the treatment. Except for a well-controlled temporal epilepsy, the boy is doing well after 6 years follow-up. AT/RT should be treated in a multimodal way. Intrathecal chemotherapy and Gamma knife radiosurgery of single recurrent or residual tumors might increase survival.

Gamma-knife radiosurgery in pediatric cerebral and skull base tumors

BACKGROUND

This retrospective study of 12 children with cerebral or skull base tumors was undertaken to evaluate morbidity and outcome after gamma-knife surgery.

PROCEDURE

Twelve consecutive children treated with stereotactic radiosurgery in a curative intent were reviewed. There were five girls and seven boys. The mean age at diagnosis was 5.8 years and at radiosurgical treatment 8.4 years. There were four pilocytic astrocytomas, two craniopharyngeomas, two pineoblastomas, two ependymomas, and two other tumors of high malignancy. We used a 201-source Co60 Leksell gamma knife and all children were treated in general anesthesia.

RESULTS

The mean tumor volume was 3.7 cm(3) and the mean tumor margin dose was 13.8 Gy. Seven patients remained stable after gamma-knife treatment with a mean follow- up of 78.6 months. One patient died during follow-up. The remaining four patients had progressive disease, two within and two outside the irradiated field, and have received further treatment. They are still alive with and without disease with a mean follow-up of 96.8 months.

CONCLUSION

Gamma-knife surgery is an effective treatment in some non-resectable cerebral and skull base pediatric tumors. In most cases, it is used in combination with other therapeutic modalities. It is safe and well tolerated.

[Treatment of acoustic neuroma]

BACKGROUND

Acoustic neuroma is the most common tumour in the cerebello-pontine angle.

MATERIAL AND METHODS

We present the results after surgery in 99 cases, and the natural course of the disease in 82 patients followed for up to 20 years (mean 3 years).

RESULTS

During the observation period, 43% of the tumours increased in size. 36% of patients suffered increasing hearing loss. Total removal was accomplished in 92 cases. In 12 cases hearing preservation was attempted; successfully in five cases. 72 patients had normal or near normal postoperative facial nerve function, whereas 19 patients got a facial nerve paralysis. Two patients died, one because of haemorrhagic infarction and cerebellar swelling, and one because of ventricular fibrillation. Five patients had to be reoperated for CSF leakage.

INTERPRETATION

Acoustic neuroma treatment is still a challenge. We favour a team approach to treat this condition.

[Stereotactic radiosurgery of cerebral arteriovenous malformations]

BACKGROUND

Different treatment modalities are being used for cerebral arteriovenous malformations.

MATERIAL AND METHODS

We have evaluated the results of stereotactic radiosurgery on 85 patients (48 females) with median age 34.5 years (range 4-70 years) treated at Haukeland University Hospital in Norway in 1989-96. Median follow-up time was 7 years 3 months (range 51-144 months). Data were obtained retrospectively from patient files.

RESULTS

Haemorrhage was the initial symptom in 72 patients. The majority of lesions were located deep within the brain parenchyma or near critical structures. The minimum dose to the periphery of the malformation was 15 to 33.3 Gy in 30-70% isodose line according to the volume and location of the malformation. Complete obliteration was obtained in 65 of 85 malformations (77%) and in two of five patients who were retreated. 85% of the malformations smaller than 4 cm3; 50% of those larger than 4 cm3 were obliterated after the treatment. The majority of the malformations were obliterated between two and three years after radiation. Radiation-related side effects were observed in six patients. Five patients experienced new bleeding during follow-up.

INTERPRETATION

Small and medium-sized arteriovenous malformations are successfully treated with stereotactic radiosurgery with an acceptable rate of radiation-related side effects and latency bleeding.

Acoustic neuroma--treatment modalities. Surgery, gamma-knife or observation?

We present our results of 211 patients with acoustic neuroma over a period of 10 years, 1988-97. We operated on 100 and 111 had Gamma-knife (GK) treatment (69 were available to follow-up). The results are excellent for surgery on small and intracanalicular tumours. In tumours of the same size, surgery and GK treatment give comparable, but somewhat different, results. In the GK group of 54 primary treated patients, 3 patients had to be operated on and another 4 developed hydrocephalus. A group of 35 acoustic tumours was observed for more than 3 years. Nineteen did grow (54%). Hearing was unchanged in 23%. We performed surgery in 11 patients and gave 2 patients GK treatment because of tumour growth of > 2 mm in diameter a year. We conclude that either treatment is effective for small and medium-sized acoustic neuromas. Hearing preservation was best in the GK-treated group (80%), compared to only 12.5% in the group operated via the suboccipital route. Larger tumours and most medium-sized tumours should be operated, as should smaller tumours with persistent symptoms of vertigo and pain. Medical contraindications to surgery or reluctance to undergo surgery make GK treatment a good alternative. Treatment of residual tumours with the GK could also be a solution to a difficult problem.

In vivo secretory potential and the effect of combination therapy with octreotide and cabergoline in patients with clinically non-functioning pituitary adenomas

The secretory capacity, in vivo, of clinically non-functioning pituitary adenomas may possibly predict tumour volume reduction during intensive medical therapy. Ten patients (mean (range) 53 years (26-73)) with clinically non-functioning macroadenomas, > or = 10 mm were studied. The secretory capacity of the adenomas was examined using basal, NaCl and TRH-stimulated LH, FSH and alpha-subunit levels. The effect on tumour volume of 6 months' therapy with the combination of a somatostatin analogue, octreotide 200 microg x 3/day and a dopamine-D2-agonist, cabergoline 0.5 mg x 1/day was studied. The basal LH, FSH and alpha-subunit levels were determined before and during 6 months' therapy with octreotide and cabergoline, and MR scans were used to evaluate tumour volume before and during this period of therapy. Octopus-perimetry was used to examine the visual fields. A reduction in tumour volume (mean +/- SEM (range); 30% +/- 4% (18-46%)) during 6 months of combination therapy with octreotide and cabergoline was recorded only in patients with in vivo secretory potential. Tumour volume was not reduced in four patients: in three of these patients it remained unchanged while in one patient it was observed to have increased (by 14%). Of the six patients with pretherapy secretory capacity, one displayed a very high basal level of alpha-subunit (74 microg/l) despite unmeasurable levels of LH and TSH, and an FSH-level of 1 IU/l. The other five patients presented paradoxical LH, FSH and/or alpha-subunit responses to TRH. A reduction in basal levels of LH, FSH and/or alpha-subunit was observed in all six patients, and the maximum reduction of at least one of the hormonal levels was 66% +/- 7% (50-98%). The basal levels of LH, FSH and alpha-subunit in the 10 patients were (mean +/- SEM (range)), 3.0 IU/l +/- 1.0 (0.0-7.4), 12.7 IU/l +/- 5.0 (0.0-39.0) and 9.0 IU/l +/- 7.0 (0.2-74.0). During six months of therapy with octreotide and cabergoline, the basal levels of LH, FSH and alpha-subunit were reduced by > or = 50% in seven patients - including the six patients with in vivo secretion prior to therapy. No new visual field defects were detected during therapy and no deterioration of existing visual field defects was recorded. The medical therapy was well tolerated. The in vivo basal and TRH-stimulated secretory capacity of LH, FSH and alpha-subunit predicted tumour reduction following intensive medical therapy in all of our patients with non-functioning pituitary adenomas.

Staging uterine cervical carcinoma with low-field MR imaging

PURPOSE

To assess the validity of low-field MR in staging cervical cancer compared to clinical staging.

MATERIAL AND METHODS

A total of 95 women entered the study over a 3-year period. MR examinations with a 0.1 T resistive magnet using a body coil and clinical staging according to the FIGO recommendations (1988) were performed within 2 weeks from clinical diagnosis. T1- and T2-weighted sequences were obtained in transversal and sagittal acquisitions, and an additional T1 before and after contrast (randomisation to 0.1 or 0.3 mmol/kg b.w. gadodiamide). Treatment decisions on surgery or radiation therapy were made solely on the clinical staging.

RESULTS

Sixty-one patients were found to be eligible for surgery. In 5 women, the pathological results revealed a more advanced stage of the disease than assessed by clinical staging. MR correctly staged 4 of the 5 but otherwise tended to overstate the disease. Contrast enhancement significantly reduced this trend (p<0.05) regardless of the contrast medium dose used. Divided into two groups, an operable (less than stage 2b) and an inoperable group (more than stage 2a), the clinical staging correctly classified 57 patients (accuracy 92%) compared to 52 patients with MR using contrast enhancement (accuracy 84%). The specificity was no higher than 31%, whereas the reproducibility of the MR assessment was fairly good with kappa values around 0.65 for both intra- and inter-observer variations.

CONCLUSION

In the present set-up, clinical assessment was superior to low-field MR in staging cervical cancer. When using contrast enhancement, the staging accuracies of low-field MR were comparable to the ones reported for techniques with higher tesla values, whereas the specificity and reproducibility errors were lower. The method, therefore, needs to be optimised.

[Atypical endometrial hyperplasia. Prognosis and course]

The treatment of patients with the diagnosis atypical endometrial hyperplasia has been disputed during the last decades. The aim of the study was to evaluate the treatment of these patients and analyse the progression rate to invasive carcinoma of the endometrium. Fifty-seven patients with atypical hyperplasia were examined and treated from 1976 through 1991. The medical records were examined retrospectively and the pathology slides were revised by one pathologist in accordance with the 1975 WHO recommendations. Thirty-one (54%) patients were on oestrogen treatment as monotherapy at the time of diagnosis. Forty-two patients had a hysterectomy performed within five months, and five patients had a hysterectomy performed 10 to 61 months after diagnosis. A total of 18 out of 57 patients (31.6%) had or developed endometrial carcinoma all with myometrial invasion: 14 stage I with < or = 50% myometrial invasion, three stage I with > 50% myometrial invasion, and one stage IV. There was no significant difference in age, body mass index, parity or hormone replacement treatment between the group with endometrial carcinoma and the group without endometrial carcinoma. We conclude that unopposed oestrogen treatment and nulliparity are the main risk factors for atypical hyperplasia and that hysterectomy is the appropriate treatment for patients with atypical hyperplasia of the endometrium.

Infection of rat brain cell aggregates with neurovirulent and nonneurovirulent strains of herpes simplex virus type 1

Rat brain cell aggregates represent a three-dimensional tissue culture system of brain tissue in the form of small, multicellular spheroids. In the present work, we have infected these "minibrains" with neurovirulent, nonneurovirulent, and nonreplicating strains of HSV-1. The neurovirulent strains 17(+) and KOS(M) spread rapidly through the aggregates, while the nonreplicating ICP4 deletion mutant KD6 infected cells only at the periphery of the aggregates. Spread and replication of the nonneurovirulent strains RE6 and tk-7, and to some extent also of R13/1, were restricted. The interaction between different strains of HSV-1 and the rat brain cell aggregates is thus comparable to that seen in the brain, suggesting that the aggregates represent a useful tool for studying HSV-1 infection of brain tissue in vitro.

Effects of DFMO on glioma cell proliferation, migration and invasion in vitro

The polyamine inhibitor DL-alpha-difluoromethylornithine (DFMO) is a specific irreversible inhibitor of ornithine decarboxylase which is a rate-limiting enzyme in the polyamine bio-synthesis pathway. The present study describes the effects of DFMO on glioma cell proliferation, migration and invasion using multicellular spheroids from three glioma cell lines (GaMg, U-251 Mg and U-87 Mg). 10 mM DFMO reduced cell migration in the three cell lines by about 30-50%. 1 mM putrescine, added together with DFMO inhibited the DFMO effect. A stronger effect was observed in the growth assay where 10 mM DFMO reduced the spheroid growth, for all cell lines, by 90%. This effect was also reversed by adding 1 mM of putrescine. In vitro tumor cell invasion experiments indicated after 3 days of confrontation, an extensive invasion also after 10 mM DFMO treatment. The brain aggregate volumes were reduced to about the same extent as in the absence of drug, suggesting essentially no effects of DFMO on the invasive process. It is concluded that the tumor spheroids retained their ability to invade normal brain tissue even after DFMO exposure. However, DFMO inhibited spheroid growth and cell migration which supports the notion that cell growth, migration and invasion are biological properties that are not necessarily related to each other.

[Patients with early stages of endometrial cancer should be spared adjuvant radiotherapy. Danish Endometrial Cancer Group]

In an attempt to create uniform nationwide guidelines for the management of all stages of endometrial carcinoma, and to limit the use of adjuvant radiation therapy in stage I disease to high-risk patients only, a protocol was developed by the Danish Endometrial Cancer group (DEMCA). From September 1986 through August 1988, 1214 women in Denmark with newly diagnosed carcinoma of the endometrium have been treated according to this protocol. This figure represents all endometrial carcinomas diagnosed in Denmark during this two-year period. The primary treatment was total abdominal hysterectomy and bilateral salpingo-oophorectomy, no preoperative radiation therapy was delivered. In 1039 cases no macroscopic residual tumour and/or microscopic tumor tissue in the resection margins was found following surgery. Based on surgery and histopathology, these patients were classified as: P-stage I low risk (n = 641), P-stage I high risk (n = 235), P-stage II (n = 105) and P-stage III, Group 1 (n = 58). No postoperative radiation therapy was given to P-I low risk cases. P-I high risk, P-II, and P-III (Group 1) cases received external radiation therapy. Recurrence rate at 68-92 months follow-up was 45/641 (7%) in P-I low risk, 36/235 (15%) in P-I high risk, 30/105 (29%) in P-II, and 27/58 (47%) in P-III (Group 1) cases. Fifteen of 17 vaginal recurrences in P-I low risk cases were salvaged (mean observation time 61 months). In this population-based investigation it has been shown that P-stage low-risk patients are adequately treated by total abdominal hysterectomy and bilateral salpingo-oophorectomy, and that no pre- or postoperative radiation therapy is necessary.

[Cerebral metastases treated with stereotaxic gamma radiation. 6-year experience with the "gamma knife" at the Haukeland hospital]

During the last 6 years we have treated 32 patients with 45 metastases to the brain in the Gamma Knife unit. 21 of these were treated exclusively with the Gamma Knife. The remaining 11 patients received radiosurgery for recurrent disease after surgery and whole-brain irradiation (six patients), new metastases after whole-brain irradiation alone (three patients) or for local regrowth after surgery (two patients). The range of tumour volume was 0.1-43.3 cm3 (median 2.4 cm3). Marginal tumour dose was 5-30 Gy (median and mean: 25 Gy) to the 30-70% isodose-volume line according to tumour volume and localization. 19 patients died during the period of follow-up. Only three patients died from their intracranial metastases. Thus, local growth control was achieved in 29 patients. 16 patients died from extracranial manifestations. The average survival time for the patients who died during the observation period was 11 (1-37 months), and the survival time for patients still alive was 10-75 (median 14, average 29) months. Mean observation period for all patients was 17 (1-75) months. Brain metastases are physically and biologically ideal lesions to treat with radiosurgery. Stereotactic radiosurgery applied to radiographically small and distinct metastases is safe, non-invasive and highly effective. The treatment requires only a short stay in hospital, and is much less inconvenient to the patient than open surgery or whole-brain irradiation. Radiosurgery can be used on lesions inaccessible to open neurosurgery or resistant to classical fractionated radiotherapy. Gamma Knife treatment has become our first choice for patients with less than four intracranial metastases with diameters less than 3-3.5 cm.

Migratory patterns of lac-z transfected human glioma cells in the rat brain

Malignant brain tumors are characterized by extensive tumor-cell infiltration into the normal brain tissue. The present work describes the migratory behavior of human glioma cells transplanted into the adult rat brain with the aim of exploiting the extent of active cell migration and passive cell displacement within the central nervous system. To detect every transplanted tumor cell, a stably bacterial beta-galactosidase (lac-z) transfected human glioma cell line was used. To distinguish between an active cell migration process and passive cell displacement, rat brains were also implanted with inert fluorescent polystyrene microspheres and the distribution of tumor cells and microspheres was studied 1 hr and 3 days after implantation. One hour after implantation the tumor cells were strictly localized at the implantation site. However, 3 days after implantation, both tumor cells and microspheres showed an extensive distribution within the brain. Confirming earlier neuropathological and experimental studies, it is shown that the lac-z-transfected glioma cells had the capacity to move within the Virchow-Robin and subarachnoid spaces. However, since fluorescent microspheres were also found in these areas, this spread of tumor cells may be primarily mediated by the extensive cerebrospinal fluid flow that exists within the brain. Three days after implantation, the glioma cells also showed an active migration over the corpus callosum. In comparison, the fluorescent microspheres showed only limited spread along the callosal body. It is concluded that the bacterial lac-z gene can be stably transfected into human glioma cells and, since every tumor cell can be visualized within the brain, this model provides a tool for studying the mechanisms behind tumor-cell invasion of the brain.

Leptomeningeal tissue: a barrier against brain tumor cell invasion

BACKGROUND

Primary brain tumors are characterized by an extensive infiltrative growth into the surrounding brain tissue. This process is confined to the central nervous system, and tumor cell metastasis to other organs is rare. However, other tumors of non-neural origin may frequently metastasize to the central nervous system.

PURPOSE

The purpose of the present study was to examine the invasive behavior of different glioma cells into tissues of neural (brain aggregates) as well as non-neural origin (leptomeningeal tissue). Using the same target tissues, the invasive characteristics of two neural metastatic tumors (one malignant melanoma and one small-cell lung carcinoma) were also studied. This direct comparison of the invasive behavior between tumors of neural and non-neural origin provides valuable information regarding the mechanisms of glioma cell dissemination in the central nervous system.

METHODS

The in vitro invasive behavior of human tumors of the central nervous system into human leptomeningeal tissue as well as into normal rat brain tissue was studied. For this purpose, a co-culture system consisting of tumor biopsy specimens, human leptomeningeal cell aggregates, and brain cell aggregates was established. Three glioblastomas, one oligodendroglioma, one meningioma, one small-cell lung carcinoma, and one malignant melanoma were studied.

RESULTS

In co-cultures of gliomas and leptomeningeal cell aggregates, a well-defined border between the two tissues was observed. The brain cell aggregates, in contrast, were consistently invaded by the glioma cells. The brain metastases showed a different invasion pattern. The metastatic cells invaded and progressively destroyed leptomeningeal cell aggregates, whereas they did not invade the brain cell aggregates. Upon confrontation of the leptomeningeal tissue with the meningioma, a fusion of the two tissues was observed. Immunostaining of the leptomeningeal tissue showed a strong expression of the basement membrane components fibronectin, collagen type IV, and laminin with no expression of glial fibrillary acidic protein, neuron-specific enolase, or S-100 protein.

CONCLUSIONS

The present study indicates that there may be important biologic differences between the invasive behavior of gliomas and non-neuroepithelial tumors. Our co-culture experiments suggest that leptomeningeal cells and associated acellular components may constitute a barrier against glioma cell invasion. However, this barrier may not be functional for metastatic tumors to the brain. The presence of glioma cells within the leptomeninges should not necessarily be taken as evidence of aggressive growth or as an indicator of malignancy.

Three-dimensional growth of glial cell lines affects growth factor and growth factor receptor mRNA levels

We have studied, at the mRNA level, the influence of various defined growth conditions on the expression of TGF-alpha, PDGF-BB, EGF-R, PDGF-R alpha, and PDGF-R beta in five different glioma cell lines (D-37MG, D-54MG, D-263MG, GaMG, and U-251MG). RNA isolated from logarithmically growing, confluent monolayer cells or multicellular spheroids was analyzed. Northern blot experiments show that with a few exceptions, specific mRNA steady-state levels were considerably higher in cells grown in a three-dimensional organization relative to cells in the logarithmic growth phase.

Transfection of glioma cells with the neural-cell adhesion molecule NCAM: effect on glioma-cell invasion and growth in vivo

The tumor growth and the invasive capacity of a rat glioma cell line (BT4Cn) were studied after transfection with the human transmembrane 140-kDa isoform of the neural-cell adhesion molecule, NCAM. After s.c. injection, the NCAM-transfected cells showed a slower growth rate than the parent cell line (BT4Cn). Upon intracerebral implantation with BT4Cn cells and different clones of NCAM-transfected cells, all animals developed neurological symptoms within 13-16 days. However, the tumors showed different growth characteristics. The NCAM-transfected BT4Cn cells were localized in the region of the injection site, with a sharply demarcated border between the tumor and brain tissue. In contrast, the parental cell line showed single-cell infiltration and more pronounced destruction of normal brain tissue. Using a 51Cr-release assay, spleen cells from rats transplanted with BT4Cn tumor cells generally showed a lower cytotoxic response than the spleen cells from rats transplanted with the transfected variants of BT4Cn cells, indicating that the transfection procedure in itself mediated an activation of the immune system. The present data suggest that NCAM may influence the malignant behavior of rat glioma cells in vivo.

Interactions between fetal rat brain cells and mature brain tissue in vivo and in vitro

Fetal as well as mature neural cells were homografted into the right cerebral hemisphere of adult BD-IX rats. The animals were sacrificed 7 d after implantation, and the localization of implanted cells was visualized by fluorescence and light microscopy. The cell implants were prestained with the fluorescent vital dye 1,1'-Dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine perchlorate (DiI) to discriminate between implanted cells and host brain tissue. At the implantation site, the fetal brain cells as well as the cells from immature brain cell aggregates showed diffuse infiltration into the surrounding host brain tissue of up to 0.5 mm. Extensive cell migration along the corpus callosum for up to 5 mm in the coronal and to a lesser extent in the sagittal plane was also observed. In addition, fetal cells were distributed in the subarachnoid space of both cerebral hemispheres and showed a distinct association with larger blood vessels. Cells from mature brain aggregates did not migrate as far as fetal cells and showed only a local infiltration into the host neuropil. Fluorescent microspheres as well as fixed fetal brain cells were implanted, either alone or in combination with vital cells to distinguish between active cell migration and passive cell displacement. The microspheres and the fixed cells were found either localized to the implantation pathway or distributed in the corpus callosum for up to 2 mm in the coronal plane without any dispersion in the sagittal plane. The microspheres also showed an extensive displacement in the subarachnoid space. In vitro co-culture experiments between two immature aggregates showed a complete fusion of the two aggregates during a 96 h culture period. In co-cultures between two mature aggregates complete fusion was not prominent, although the confrontation zone appeared diffuse. Confrontations between a mature and an immature aggregate showed the same pattern of interaction as seen for the two mature aggregates. It is concluded that carbocyanine dyes may be used as a tracer for transplanted cells. Cells from fetal rat brain cell aggregates, opposed to those from mature aggregates, showed extensive migration along well defined anatomical structures in the mature along well defined anatomical structures in the mature brain. Some of the spread of cells following implantation is probably due to passive movement since inert microspheres will spread into certain areas of the CNS.

Heterogeneous response to the growth factors [EGF, PDGF (bb), TGF-alpha, bFGF, IL-2] on glioma spheroid growth, migration and invasion

The effects of 5 different growth factors [EGF, PDGF(bb), TGF-alpha, bFGF and IL-2] were studied on tumour spheroids obtained from 5 different human glioma cell lines (U-251MG, D-263MG, D-37MG, D-54MG, GaMG). The expression of EGF and PDGF receptors as well as the endogenous production of TGF-alpha and PDGF were studied by Northern blot analyses. After growth-factor-exposure, tumour spheroid volume growth, and directional cell migration from the spheroids were studied. In addition, tumour-cell invasion was studied in vitro, where foetal rat-brain aggregates were used as a target for the tumour cells. In all the assays a common stimulator for most of the cell lines was EGF. The other growth factors had a more heterogeneous stimulatory effect. Tumour-cell invasion, cell growth and cell migration are biological properties which are not necessarily related to each other. This may explain why the tumours often responded differently to the growth factors in the various assay systems. Two of the cell lines studied were non-invasive (U-251MG, D-263MG). It is shown that these were stimulated both in the directional migration assay and in the spheroid-volume-growth assay. However, their non-invasive behaviour was not influenced by the growth factors studied.

Migratory pattern of fetal rat brain cells and human glioma cells in the adult rat brain

The migratory behavior of two human glioma cell lines (D-54MG and GaMG) and fetal rat brain cells grafted into the adult rat brain was studied. To trace the implanted cells, they were stained with the carbocyanine vital dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate before injecting them into the white matter above the corpus callosum. The animals were sacrificed 2 h and 7 and 21 days after injection, and the brains were removed and cryosectioned. Fluorescence microscopy showed that both the 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-stained fetal and tumor cells had the same migratory pattern. Implanted cells were found along myelinated fibers in the corpus callosum and in the perivascular space. After immunostaining for several extracellular matrix (ECM) components (laminin, fibronectin, collagen type IV, and chondroitin sulfate), laminin deposits were observed in the border zone between the host tissue and implanted tumor cells as well as fetal cells. By using two different types of antibodies against fibronectin, it is shown that the fibronectin expression observed in the tumor matrix may be host derived. This was further supported by the fact that tumor spheroids obtained from the two glioma cell lines were negative when immunostained for these ECM components. Several of the ECM components may be host derived. This can be caused by neovascularization and repair synthesis or by a local production of guiding substrates which are important for tumor cell locomotion. The present data suggest that the migratory patterns of fetal and glioma cells are indistinguishable when transplanted into the adult rat brain. Thus, glioma cells may be routed by the same ECM components that play a major role during brain development.

Effects of EGF, bFGF, NGF and PDGF(bb) on cell proliferative, migratory and invasive capacities of human brain-tumour biopsies in vitro

Spheroids initiated directly from human primary gliomas were used to investigate the effects of EGF, bFGF, NGF and PDGF(bb) on cell proliferation, migration and invasion into foetal rat brain tissue. EGF increased tumour spheroid volume in 10 of 13 glioblastomas studied, whereas 5 of 11 tumours responded to bFGF. NGF increased the spheroid volume in 2 of 5 tumours. In 8 tumours, PDGF(bb) had no effect on tumour spheroid volume. An increase in BUdR-labelling indices confirmed that cell proliferation was responsible for the volume increase observed in stimulated spheroids. EGF stimulated cell migration in 5 and bFGF in 3 of 8 tumours studied. NGF stimulated cell migration in 1 of 5 glioblastomas, whereas 1 of 3 glioblastomas responded to PDGF(bb). The effects of growth factors on the invasion of spheroids prepared from the glioblastoma biopsy specimens were also studied in vitro using foetal rat brain aggregates as target tissue. EGF stimulated invasion in 7 of 8 glioblastomas studied, whereas bFGF stimulated invasion in 2 of these tumours. NGF or PDGF(bb) did not increase the invasiveness of the glioblastoma tissue. Our results represent the net effect of the growth factors on a complex tumour-cell population. We conclude that exogenously administered growth factors, EGF in particular, increase the cell proliferation as well as migratory and invasive capacities of cultured primary brain tumour biopsies in vitro.

Benign intracerebral cysts treated with internal shunts: review and report of two patients

Two elderly women with symptomatic benign intracerebral cysts are reported. Before treatment, they both had developed moderate, but slowly increasing, symptoms from a cyst in the left hemisphere, which included epileptic seizures and right hemiparesis. During local anesthesia, an internal cystosubarachnoid shunt was inserted. After the operation, the cyst size was reduced markedly, with a corresponding improvement in the symptoms. A review of reported cases of benign intracerebral cysts is given. The average age of these patients is surprisingly high for a presumed congenital condition. There is a female preponderance, but the previously reported overrepresentation of left-sided lesions is not found in cases described after the introduction of computerized tomographic imaging.