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Background: A substantial number of patients with brain tumors develop recurrent seizures, known as tumor-associated epilepsy. It is important to identify specific subgroups of brain tumor patients with higher incidences of epilepsy because a meta-analysis failed to certify the effectiveness of prophylactic anti-epileptic drugs (AEDs) to abort tumor-associated epilepsy as a whole., Methods: To investigate the relationship between tumor location and incidence of epilepsy, we performed voxel-wise comparison between 3D MRI scans obtained from patients with meningioma-associated epilepsy and those from control patients using spatial normalization techniques on neuroimaging data. Variables such as age, tumor size, the degree of edema, and pathological diagnosis were also compared between the two groups., Results: Our results showed the highest incidence of epilepsy when the tumor was located on the premotor cortex in the frontal lobe (Z-scores >2.0, Liebermeister's quasi-exact test). The stepwise multiple regression analysis on the clinical data revealed that the tumor diameter (p < 0.001) and the patient's age (p = 0.024) were positive and negative predictors, respectively, for the onset of epilepsy., Conclusions: The incidence of epilepsy was higher in meningiomas located on the premotor cortex than on the other cortex. Larger volume also contributed to the onset of epilepsy. We suggest that variations of epilepsy incidence dependent on tumor characteristics can be considered when treating tumor-associated epilepsy.

Meningiomas are the most frequent intracranial tumors. Although most are benign WHO grade I tumors, grade II and III tumors are aggressive and survival is poor. Treatment options for grade II and III meningiomas are limited, and molecular targets are few. The re-programming of metabolic pathways including glycolysis, lipogenesis, and nucleotide synthesis is a hallmark of the physiological changes in cancer cells. Because fatty acid synthase (FAS), the enzyme responsible for the de-novo synthesis of fatty acids, has emerged as a potential therapeutic target for several cancers, we investigated its involvement in meningiomas. We subjected 92 paraffin-embedded samples from 57 patients with grade I, 18 with grade II and III, and six with radiation-induced tumors to immunohistochemical study of FAS. Whereas its expression was increased in grade II and III meningiomas (62.9 %) compared with grade I tumors (29.8 %) (chi-squared test: p < 0.001), FAS was expressed in grade I tumors with a high MIB-1 index and infiltration into surrounded tissues. All radiation-induced meningiomas expressed FAS and its expression was positively correlated with the MIB-1 index (p < 0.005). Our findings suggest that increased FAS expression reflects the aggressiveness of meningiomas and that it may be a novel therapeutic target for treatment of unresectable or malignant tumors.

High-grade (World Health Organization grades II and III) meningiomas grow aggressively and recur frequently, resulting in a poor prognosis. Assessment of tumor malignancy before treatment initiation is important. We attempted to determine predictive factors for high-grade meningioma on magnetic resonance (MR) imaging before surgery. We reviewed 65 meningiomas (39 cases, benign; 26 cases, high-grade) and assessed four factors: (1) tumor-brain interface (TBI) on T1-weighted imaging (T1WI), (2) capsular enhancement (CapE), i.e., the layer of the tumor-brain interface on gadolinium-enhanced T1WI (T1Gd), (3) heterogeneity on T1Gd, and (4) tumoral margin on T1Gd. All four factors were useful in distinguishing high-grade from benign meningiomas, according to univariate analysis. On multivariate regression analysis, unclear TBI and heterogeneous enhancement were independent predictive factors for high-grade meningioma. In meningiomas with an unclear TBI and heterogeneous enhancement, the probability of high-grade meningioma was 98%. Our data suggest that this combination of factors obtained from conventional sequences on MR imaging may be useful to predict high-grade meningioma.

We report three patients with non-germinomatous malignant germ cell tumor (NGMGCT) who developed therapy-associated secondary tumors. They were diagnosed as having NGMGCT by elevated serum levels of α-fetoprotein (AFP), human chorionic gonadotropin (HCG), or β-HCG. Preoperatively, all patients received a combination of etoposide and platinum-based chemotherapy and radiotherapy; neo-adjuvant therapy (NAT) was followed by complete excision of the residual tumor. Postoperatively, all underwent maintenance chemotherapy and all remained free of NGMGCT without recurrence. However, they developed therapy-associated secondary tumors, i.e. glioblastoma, meningioma, or cavernous angioma after 10.1, 9.8, and 8.2 years, respectively. The patient with glioblastoma died one year after its detection. The other two patients are currently alive; the meningioma was completely removed and the cavernous angioma is being monitored without additional treatment. To the best of our knowledge, therapy-associated secondary tumors in patients treated for NGMGCT are rare.

A 64 year-old woman with a diagnosis of lung adenocarcinoma was admitted to our neurosurgical division in February, 2007, suffering from severe headache and dizziness. Systemic chemotherapy had been repeated for multiple metastases to the bone and cerebral cortex since 7 months before. Reexamination with MRI revealed mild hydrocephalus without cortical metastasis. Cytological analysis of the cerebrospinal fluid (CSF) provided the diagnosis of leptomeningeal metastasis. Removal of 8 ml of CSF dramatically alleviated the patient's symptoms. To improve the quality of her remaining life, she underwent lumboperitoneal (L-P) shunt using a Strata adjustable pressure valve. Severe headache disappeared and other symptoms gradually improved after the operation. She survived for 10 months after the shunt placement, perticipating in family life for 6 months. Pressure level of the Strata valve was changed twice according to the degree of hydrocephalus and functioned well while her life lasted. The present case showed that L-P shunt is one of the effective palliative procedures and an adjustable pressure valve is available for this kind of CSF shunt in patients with leptomeningeal metastasis.

Introduction: Cellulose porous beads (CPBs) are exceptionally uniform in size and nonabsorbable and they provide highly effective tumor devascularization. The risk of cranial nerve palsy must not be overlooked when embolization with CPBs is considered in meningioma patients. We attempted to identify patients at risk of cranial nerve palsy after meningioma embolization., Methods: Prior to preoperative superselective embolization with 200 mum diameter CPBs, 141 patients with meningioma underwent provocation test with lidocaine and amytal. They were divided into two groups on the basis of whether they were or were not considered eligible for embolization. We evaluated the differences between the two groups with respect to tumor anatomy, angiographic findings, and clinical presentation and recorded complications associated with the embolization of the meningioma., Results: Of the 141 patients, 128 underwent CPB embolization (group 2); 13 were not embolized because their provocation test results were positive (group 1, n = 11) or because they showed vasospasm (n = 2). Group 1 patients had meningioma in the cavernous sinus or petroclival region. Characteristically, the feeders were of middle meningeal artery origin and exhibited a posteromedial course toward the petrous apex or cavernous sinus. In group 2 patients the middle meningeal artery was the feeder, but it lacked branches coursing posteromedially. Three of these patients experienced complications which included intratumoral hemorrhage (n = 2) and post-embolization hearing disturbance (n = 1)., Conclusion: Patients with meningioma whose tumor-feeding arteries run posteromedially toward the petrous apex or cavernous sinus are at increased risk of post-embolization cranial nerve palsy. Appropriate protocols, including lidocaine and amytal provocation tests, may reduce the risk of complications after CPB embolization of the external carotid territory in this group of patients.

This 77-year-old woman with a rapidly enlarging chordoid meningioma first noticed a growing, non-pulsatile, nonpainful soft mass in the left temporal region after a head trauma 2 years earlier. Neuroimaging showed a homogeneously enhanced osteolytic mass lesion in the left temporal bone. Surgery revealed an extradural tumor without significant adhesions. Histopathologically it was a meningioma with features reminiscent of chordoma. Most of the tumor cells contained mucin-rich chordoid elements. Immunohistochemically, the lesion was positive for vimentin and epithelial membranous antigen; it was negative for cytokeratin and S-100 protein. Based on these findings a diagnosis of chordoid meningioma was made. We posit that the rapid enlargement of the tumor over a relatively short period was attributable to its high mucin-producing activity.

Object: To determine the indications for surgery in patients harboring asymptomatic meningiomas, the authors retrospectively analyzed the natural course and surgical outcome of asymptomatic meningiomas and then compared these to the natural course and surgical outcome of symptomatic meningiomas., Methods: Between 1989 and 2003, 1434 patients harboring meningiomas, who were treated in Kumamoto Prefecture, Japan, were enrolled in this study. Six hundred three patients had asymptomatic lesions and 831 had symptomatic ones. The authors analyzed the sizes of the lesions at detection, their growth over time, and any appearances of symptoms associated with previously asymptomatic meningiomas. The authors then compared the surgery-related morbidity rates associated with asymptomatic and symptomatic meningiomas arising at different locations. Of the 603 asymptomatic meningiomas, 351 (58.2%) were treated conservatively. Tumor growth was observed in 25 (37.3%) of 67 patients who participated in follow up for longer than 5 years, and symptoms developed in 11 (16.4%) of the 67 patients over a mean follow-up period of 3.9 years. Among the 213 patients with surgically treated asymptomatic meningiomas, the morbidity rate was 4.4% in patients younger than 70 years of age and 9.4% in those 70 years of age or older. Although the total morbidity rate was lower in patients with asymptomatic lesions than in those with symptomatic ones, it exceeded 6% in patients whose asymptomatic tumors were located at the convexity or falx., Conclusions: Approximately 63% of asymptomatic meningiomas did not exhibit tumor growth, and only 6% of all patients with these lesions experienced symptoms during the observation period. To avoid surgery-related incidences of morbidity in patients with asymptomatic meningiomas, conservative treatment with close follow-up review may be the best therapeutic strategy.

We describe herein the case of a 68-year-old man who experienced leptomeningitis after esophagectomy from an esophageal basaloid carcinoma. Although the patient had a good operative course for the first 10 days after surgery, he suddenly had general convulsions with unconsciousness. He was placed on mechanical ventilation in an intensive care unit. Computed tomography and magnetic imaging resonance did not reveal any abnormal findings. No abnormal data in the cerebrospinal fluid were found by biochemical, virological, and cytological examination. The positive expression of carcinoembryonic antigen messenger ribonucleic acid in cerebrospinal fluid was detected by a quantitative reverse transcription-polymerase chain reaction method. Immunohistochemical staining using an anticytokeratin antibody confirmed the presence of tumor cells in the cerebrospinal fluid. Spontaneous breathing was recovered after treatment with systemic chemotherapy. Six months after surgery, computed tomography revealed multiple brain metastases. This case demonstrates that the quantitative reverse transcription-polymerase chain reaction method of analyzing carcinoembryonic antigen messenger ribonucleic acid may be a sensitive and useful method for determining leptomeningeal metastasis before the detection of tumors by cytological and imaging examinations in patients with cancer.

Background: Haemorrhage from meningiomas is rare and the underlying pathophysiological mechanisms remain to be determined. We sought to identify these mechanisms by studying clinical and histological records of 6 meningioma patients treated at our institution., Patients and Methods: We retrospectively studied 6 patients with meningiomas whose acute onset was due to haemorrhage. We evaluated clinical features and imaging studies. The vascularity and proliferative nature of these tumours were examined immunohistochemically and tissue factor (TF) immunoreactivity was assessed. For comparison we evaluated 25 non-haemorrhagic meningiomas., Findings: At onset, the haemorrhages mimicked stroke in all 6 patients. On imaging studies, 3 of the haemorrhages were intra- and extratumoural, the other 3 were extratumoural only. Hyperintensity on T2-weighted MRI was a characteristic of these meningiomas. Histologically, they were of 3 subtypes, meningothelial (n=3), transitional (n=2), and anaplastic (n=1). The MIB-1 labelling index of the 5 WHO Grade I meningiomas was 5.8+/-2.2. The mean number of CD31-positive blood vessels did not differ in haemorrhagic and non-haemorrhagic meningiomas. The TF-positivity rate of haemorrhagic meningiomas was higher than of non-haemorrhagic meningiomas., Interpretation: The proliferative nature of the meningiomas and TF expression in tumour cells may have contributed to the eventual haemorrhage of the meningiomas in our series.

Chondromas arising from the dura mater are rare intracranial tumors. The authors present a case of intracranial giant chondroma originating from the dura mater of the convexity. Neuroimaging and surgical findings are described. The diagnostic clues are discussed and similar cases from the literature are reviewed.

Object: The increased use of computerized tomography (CT) and magnetic resonance (MR) technology has led to an increase in the detection of asymptomatic meningiomas, although the surgical indication for these tumors remains undetermined. The authors investigated the incidence of asymptomatic meningiomas and their clinical features., Methods: An epidemiological survey was conducted of primary intracranial tumors diagnosed in Kumamoto Prefecture between 1989 and 1996. Follow-up neuroradiological imaging and clinical studies for asymptomatic meningiomas were performed. Primary intracranial tumors were diagnosed in 1,563 residents. Of these lesions, 504 (32.2%) were meningiomas, and of these meningiomas 196 (38.9%) were asymptomatic. The incidence of asymptomatic meningiomas was significantly higher in individuals older than 70 years of age. Furthermore, the incidence of asymptomatic meningiomas was significantly higher in female than in male patients. Of the asymptomatic meningiomas in 196 patients, 87 (44.4%) were surgically removed, whereas 109 (55.6%) were treated conservatively. Of these conservatively treated patients, 63 received follow-up care for more than 1 year. In 20 of these 63 cases, the tumors increased in size over the 27.8-month average follow-up period (range 12-87 months), whereas in the other 43 cases, the tumor size did not increase during a 36.6-month average follow-up period (range 12-96 months). There was no significant difference with respect to age, tumor size, and male/female ratio between the patient group in which the tumor size increased and the group in which it did not increase during the follow-up period. Asymptomatic meningiomas that evidenced calcification on CT scans and/or hypointensity on T2-weighted MR images appear to have a slower growth rate., Conclusions: Among patients older than age 70 years who underwent operation for asymptomatic meningioma, the neurological morbidity rate was 23.3%; it was 3.5% among younger patients. This indicates that the advisability of surgery in elderly patients with asymptomatic meningiomas must be considered very carefully.

Background: The spinal seeding from brain tumors sometimes mimicks fungal meningitis on examination of cerebrospinal fluid., Methods and Results: A 19-year-old woman gradually developed increased intracranial hypertension. MRI identified a mass in the right parieto-occipital area. It was totally removed and histologically diagnosed as an anaplastic ependymoma. Radiation- and chemotherapy were administered postoperatively. The patient reported low back pain 5 months after the surgical treatment. MRI disclosed neither spinal dissemination nor tumor recurrence at the primary site. Lumbar puncture was performed and the cerebrospinal fluid (CSF) was found to have an extremely low glucose level (5 mg/dl); no tumor cells were identified. Blood samples were obtained and a relative increase of WBC and CRP was noted. A slight degree of inflammation and low-grade fever were recorded. A tentative diagnosis of fungal meningitis was made and anti-fungal therapy was administered transventricularly and transvenously. However, her neurological condition continued to deteriorate gradually. Sequential CSF studies showed that the glucose level remained extremely low, it even decreased to 0 mg/dl Eight months after the surgical treatment, MRI with Gd-DTPA revealed marked subarachnoid enhancement in both intracranial and spinal areas. An open biopsy was performed and a histological diagnosis of intracranial and spinal seeding of the anaplastic ependymoma was returned., Conclusions: We report a patient with intracranial and spinal seeding of an anaplastic ependymoma that mimicked fungal meningitis. We discuss the difficulty of obtaining a differential diagnosis in this case and describe the mechanism of the decreased CSF glucose level.

Objective: For the treatment of elderly patients with asymptomatic meningiomas, it is important to determine their natural history. Based on results of follow up examinations, the natural history of such patients was clarified and prognostic factors concerning the potential of tumour growth in the aged were identified., Methods: The clinical records and imaging studies of 40 elderly (over 70 years) patients with asymptomatic meningiomas were analysed. The patients were followed up with repeated imaging studies, and changes in tumour size, clinical signs, and outcomes were evaluated., Results: There were 32 women and eight men with a mean age of 76.1 years. The mean follow up period was 38.4 months, ranging from 6 to 97 months. Six patients died during the follow up period from disorders other than the tumours, and one patient died as a result of the tumour. Twenty six patients (mean follow up period 41.8 months, range 10-97 months) showed no tumour growth. Fourteen patients showed tumour growth (mean follow up period 32.1 months, range 6-88 months). Five (four men and one woman) of these patients became symptomatic. Based on imaging analysis (1) calcification of the tumour was associated with no tumour growth (p=0.036), and (2) the tumour size at the initial diagnosis was related to subsequent tumour growth (p=0.016). Other possible factors related to tumour growth included sex and hyperintensity on MRI T2 weighted images., Conclusion: In elderly patients with asymptomatic meningiomas, careful clinical follow up with imaging studies is important. The imaging features mentioned may contribute to prediction of tumour growth.

A 67-year-old male presented with an atypical meningioma arising from the right tentorium associated with a venous angioma in the left cerebellar hemisphere. The venous angioma was detected incidentally during examinations for the brain tumor. The brain tumor was removed completely and the venous angioma followed conservatively. Venous angiomas associated with brain tumors should be followed conservatively, as the clinical significance and surgical indications are unclear.

We studied 23 patients with meningiomas and 14 with schwannomas using dynamic spin-echo (TR/TE 200/15 ms) MRI. Histologically the meningiomas were classified according to the 1993 WHO classification. Serial images were obtained every 30s for 210s after rapid injection of gadopentetate dimeglumine (0.1 mmol/kg). The contrast-enhancement ratio (CER) was divided into three patterns; a sharp rise with a peak within 60 s (A), a relatively rapid increase with a peak between 60 and 210s (B), a slow increase without a peak (C). The patterns were correlated with the histology of the tumors. The signal intensities of the tumours on T2-weighted images were also analyzed and correlated with the dynamic patterns. Meningiomas had more varied dynamic patterns than schwannomas. Almost half of the meningiomas showed pattern A, and one third pattern C. Of six meningiothelial meningiomas showed pattern A; all schwannomas and fibrous meningiomas showed pattern C. Various patterns were observed in transitional meningiomas. Of the 8 meningiomas showing pattern C, only one gave high signal on T2-weighted images, and could not be differentiated from the schwannomas. Thus, one third of meningiomas could not be differentiated from schwannomas by the dynamic contrast enhancement alone. However, when this was combined with the signal intensity on T2-weighted images, most meningiomas could be differentiated from schwannomas.

1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), one of the chloroethyl nitrosoureas, is effective against malignant glioma. To develop its use in intrathecal chemotherapy, we encapsulated BCNU in hybrid liposomes composed of dimyristoylphosphatidylcholine and micellar surfactants (Tween 20) and dissolved it in artificial cerebrospinal fluid (lipo-BCNU). We then studied the toxicity of hybrid liposomes and cellular proliferation inhibition of lipo-BCNU in vitro. We found that 3 mM hybrid liposomes did not affect the viability of human endothelial cells and that lipo-BCNU inhibited the proliferation of human glioma cell lines U-105MG, U-251MG, and U-373MG, and rat glioma cell lines C6 and 9L in a concentration-dependent fashion. Wistar rats that were administered lipo-BCNU intracisternally showed no weight loss, neurological symptoms, or histological changes of the brain and spinal cord. A Wistar rat model of meningeal gliomatosis was established by intracisternal inoculation of 0.1 ml cell suspension containing 1 x 10(6) or 5 x 10(6) viable C6 glioma cells. Two days after inoculation, lipo-BCNU (BCNU, 2.5 mg/kg) was administered intracisternally. When 1 x 10(6) glioma cells were inoculated (experiments 1 and 2), the median survival times were 24.5 and 26 days in the control groups and 32 and 45 days in the lipo-BCNU-treated groups. respectively. When 5 x 10(6) glioma cells were inoculated (experiments 3-6), the median survival times were 17-29.5 days in the control groups and 23-44 days in the treated groups, respectively. Significantly prolonged survival was obtained in three of six experimental groups. After the administration of 1 ml lipo-BCNU (BCNU, 4.67 mM) or 1 ml BCNU solubilized with 5% dextrose/water (BCNU, 4.67 mM) into the cisterna magna of dogs, the cisterna magna cerebrospinal fluid was sampled, and the BCNU concentrations were assayed by high-performance liquid chromatography. The half-life of the lipo-BCNU was longer than that of BCNU solubilized with 5% dextrose/water. These results suggest that the intrathecal administration of lipo-BCNU may be possible for the treatment of meningeal gliomatosis.

The magnetic resonance imaging appearance of 40 surgically confirmed intracranial meningiomas was reviewed to correlate signal intensity on T2-weighted images with histological subtypes of meningioma. A moderate variation of signal intensity was found within a given histological subtype. The mean signal intensity scores on T2-weighted images of the fibrous type of meningioma were significantly lower than those of the other types, and were correlated with the collagen content. The signal intensity of meningiomas on T2-weighted images crudely predicts the histological type. Tumors significantly hypointense compared to the cortex are composed primarily of fibrous elements.

We report on the toxicity, intrathecal pharmacokinetics, and therapeutic effect of the ventriculolumbar perfusion of 3-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-1-(2-chloroethyl)-1-nitros our ea hydrochloride (ACNU) against the subarachnoid dissemination of primary central nervous system tumors. Fifteen patients received ventriculolumbar perfusion of ACNU. One was treated with ventriculolumbar perfusion of ACNU alone, and the others underwent concomitant systemic chemotherapy; three of these patients received irradiation as well. ACNU was administered at an initial dose of 0.5 and was increased to 1.5 to 10.0 mg in six patients. Because of a lack of Level 2 or greater toxicity, the subsequent seven patients received 8.7 to 10.0 mg of ACNU dissolved in artificial cerebrospinal fluid (CSF) at a concentration of 0.1 mg/ml, from the start of the treatment. During ACNU administration, the lumbar CSF was drained at approximately the same rate as that of the infusion. Twelve patients received from 3 to 42 courses (average, 14 courses). The cumulative dose of ACNU ranged from 5 to 330.4 mg (average, 82.9 mg). One patient had a convulsion; two patients experienced transient headache, nausea, and vomiting; two others reported transient headache, nausea, vomiting, and fecal incontinence; and one experienced transient nausea, vomiting, and fecal incontinence. No side effects were noted in the other nine patients. When 9.0 to 9.5 mg of ACNU, dissolved in 90 to 95 ml of artificial CSF, was administered for 37 to 52 min, the maximum concentration of ACNU in the lumbar CSF was 9.86 to 12.79 micrograms/ml and the area under the drug concentration-time curve was 260.8 to 502.5 micrograms.min/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Histochemical analysis of frozen, thin sections revealed the distribution of alkaline phosphatase (ALPase) in 47 primary intracranial neoplasms in humans. The cytoplasm of meningioma cells exhibited the strongest ALPase reactivity. Pretreatment of these materials by levamisol indicated that the isozymes of ALPase had the characteristic liver-bone-kidney form. In meningiomas and astrocytomas, there was no particular relationship between ALPase activity and malignancy. In neurinomas, there was weak ALPase reactivity in a few neoplastic cells. These findings are suggestive of diagnostic implications for fibroblastic meningiomas and neurinomas at the light microscopic level.

Seven cases of intracranial hemangiopericytoma were studied retrospectively to investigate the efficacy of radiation therapy. Tumor response evaluated by computed tomography and magnetic resonance imaging was obvious after 20-30 Gy irradiation. The total reduction rate was 80-90% and continued as long as 5-7 months after treatment. In five patients receiving radiation therapy before radical removal, the tumors were easily removed without massive hemorrhage. Histological inspection of specimens after irradiation showed a significant disappearance of tumor cells. Pyknosis frequently occurred in endothelial cells, and proliferating vessels with hyalinoid degeneration were also seen. Reticulin fibers between tumor cells were fewer, split, or absent. Preoperative radiation therapy is useful in the treatment of hemangiopericytoma involving considerable surgical risk. Postoperative radiation therapy should be given even if removal is complete.

A 13-year-old boy with an anaplastic meningioma at the site of the jugular foramen had an increased serum level of aklaline phosphatase (ALPase) (liver form) in the serum before surgery. Immediately after excision of the tumor, the serum ALPase level decreased dramatically. Histochemical and immunohistochemical examinations revealed ALPase activity (liver form) in the neoplastic cells. This case would be the third with clinical evidence that the increased level of serum ALPase is of neoplastic cell origin from the meningioma. The implications of ALPase in brain tumors are discussed.

A rare case of intracranial hemangiopericytoma associated with a large cyst was treated by gross total removal and local irradiation. The tumor has not recurred for 16 months, although the effectiveness of radiation therapy for hemangiopericytoma is unclear. Histological examination of the tumor specimen showed aggregation of the microcystic components, possibly contributing to the cyst formation. Hemangiopericytoma should not be classified as meningioma because of the different neoplastic and cytological properties. Complete surgical removal is essential for this tumor because of its malignancy.

A 56-year-old male with a 11-month history of late-onset epilepsy was hospitalized because of status epilepticus. The physical examination and laboratory data were normal. Neurological examination revealed weakness of the right leg. Coronal computed tomography showed a mass of slightly high density in the bilateral parietal convexity, with homogeneous enhancement by contrast medium. Magnetic resonance imaging disclosed an en-plaque epidural tumor in the parietal region along the superior sagittal sinus, which was normointense on T1- and T2-weighted images. Conventional and digital subtraction angiography showed an avascular mass between the superior sagittal sinus and the inner table of the skull at the parietal region. The mass was thought to be situated in the parietal epidural space. On surgery, however, the tumor was found to be located mainly in the dura and subdural space. The histological diagnosis was malignant lymphoma of the B cell type. Ga-scintigraphy, physical examination, and bone marrow and peripheral blood examinations disclosed no systemic abnormalities. Therefore, the tumor was interpreted as a primary intracranial malignant lymphoma. Reports of primary intracranial malignant lymphoma have been increasing, but most have been located in the cerebrum. The dural-subdural location in this case is evidently rare.

We examined the level of sialic acid in cerebrospinal fluid (CSF) in 20 patients with brain tumor, and 5 patients with non-neoplastic disease of central nervous system. CSF concentration of sialic acid in the patients with malignant and semi-malignant or benign brain tumor was 5.26 +/- 2.39 mg/dl, and 1.82 +/- 1.61 mg/dl, respectively. In patients with non-neoplastic disease, it was 1.64 +/- 1.53 mg/dl. The difference between groups was statistically significant (p less than 0.005). In two patients with malignant brain tumor, the level of sialic acid was decreased by radiation therapy or intrathecal chemotherapy. In conclusion, CSF concentration of sialic acid was significant of diagnosis of brain tumor character of malignancy, and effect of therapy for CSF dissemination.