(1/1082) SPARC: a potential diagnostic marker of invasive meningiomas.
SPARC, a secreted, extracellular matrix-associated protein implicated in the modulation of cell adhesion and migration, was evaluated as a marker for invasive meningiomas. Although the majority of meningiomas are clinically and morphologically benign, approximately 10% progress into atypical and malignant tumors, according to the standard criteria. However, a subset of meningiomas presents as histomorphologically benign tumors (WHO grade I), but they are clinically invasive. It has been suggested that these tumors should be classified as malignant, and that the patients may require adjuvant therapy and closer follow up. Unfortunately, a significant number of these tumors may not be recognized because the surgical specimen used to assess the grade of a tumor lacks the infiltrative interface with the brain, which is currently necessary to determine its invasive character. Therefore, a marker of heightened invasiveness would greatly facilitate the identification of this subset of patients. In this study, the immunohistochemical expression of SPARC in benign, noninvasive primary meningiomas was compared with its expression in invasive, aggressive, primary and recurrent meningiomas. SPARC was not expressed in the 9 benign, noninvasive tumors, but was highly expressed in the 20 invasive tumors, regardless of the grade. The findings suggest that SPARC is a potential diagnostic marker of invasive meningiomas and is capable of distinguishing the histomorphologically benign noninvasive from the histomorphologically benign but invasive meningiomas, in the absence of the infiltrative interface. (+info)
(2/1082) Neurologic complications of systemic cancer.
Neurologic complications occur frequently in patients with cancer. After routine chemotherapy, these complications are the most common reason for hospitalization of these patients. Brain metastases are the most prevalent complication, affecting 20 to 40 percent of cancer patients and typically presenting as headache, altered mental status or focal weakness. Other common metastatic complications are epidural spinal cord compression and leptomeningeal metastases. Cord compression can be a medical emergency, and the rapid institution of high-dose corticosteroid therapy, radiation therapy or surgical decompression is often necessary to preserve neurologic function. Leptomeningeal metastases should be suspected when a patient presents with neurologic dysfunction in more than one site. Metabolic encephalopathy is the common nonmetastatic cause of altered mental status in cancer patients. Cerebrovascular complications such as stroke or hemorrhage can occur in a variety of tumor-related conditions, including direct invasion, coagulation disorders, chemotherapy side effects and nonbacterial thrombotic endocarditis. Radiation therapy is the most commonly employed palliative measure for metastases. Chemotherapy or surgical removal of tumors is used in selected patients. (+info)
(3/1082) Leptomeningeal metastasis after surgical resection of brain metastases.
OBJECTIVE: To determine the incidence and risk factors for leptomeningeal metastasis after surgery for brain metastasis of solid tumors. METHODS: Review of the records of all patients operated on for brain metastasis between January 1990 and August 1995. RESULTS: In this period 28 patients underwent surgery for brain metastasis, of whom 27 were available for evaluation in this study. Median survival after craniotomy was 11 months. Nine patients (33%) developed leptomeningeal metastasis 2-13 months after surgery, which included six of the nine patients operated on for posterior fossa metastasis (p=0.05). In five patients, leptomeningeal metastasis was the only site of recurrence. Three patients developed the leptomeningeal metastasis as bulky tumour along the spinal cord, which is a rare presentation. No other risk factors for the development of leptomeningeal metastasis other than surgery for posterior fossa metastasis were identified. CONCLUSIONS: There is an increased risk of leptomeningeal metastasis after surgery for posterior fossa metastasis. Future trials should consider the value of an active approach to this complication in these patients. (+info)
(4/1082) Hemangioblastoma mimicking tentorial meningioma: preoperative embolization of the meningeal arterial blood supply--case report.
A 72-year-old male presented with a primary hemangioblastoma of the posterior fossa with unusual dural attachment and meningeal arterial blood supply from the external carotid artery and marginal tentorial artery. Preoperative embolization facilitated complete resection of the tumor with no resultant neurological deficit. Hemangioblastoma must be included in the differential diagnosis of tumors with dural involvement. Preoperative embolization is very useful in such tumors. (+info)
(5/1082) Cerebral veins: comparative study of CT venography with intraarterial digital subtraction angiography.
BACKGROUND AND PURPOSE: Our objective was to compare the reliability of CT venography with intraarterial digital subtraction angiography (DSA) in imaging cerebral venous anatomy and pathology. METHODS: In 25 consecutive patients, 426 venous structures were determined as present, partially present, or absent by three observers evaluating CT multiplanar reformatted (MPR) and maximum intensity projection (MIP) images. These results were compared with the results from intraarterial DSA and, in a second step, with the results of an intraobserver consensus. In addition, pathologic conditions were described. RESULTS: Using DSA as the standard of reference, MPR images had an overall sensitivity of 95% (specificity, 19%) and MIP images a sensitivity of 80% (specificity, 44%) in depicting the cerebral venous anatomy. On the basis of an intraobserver consensus including DSA, MPR, and MIP images (415 vessels present), the sensitivity/specificity was 95%/91% for MPR, 90%/100% for DSA, and 79%/91% for MIP images. MPR images were superior to DSA images in showing the cavernous sinus, the inferior sagittal sinus, and the basal vein of Rosenthal. Venous occlusive diseases were correctly recognized on both MPR and MIP images. Only DSA images provided reliable information of invasion of a sinus by an adjacent meningioma. CONCLUSION: CT venography proved to be a reliable method to depict the cerebral venous structures. MPR images were superior to MIP images. (+info)
(6/1082) In vivo hydrogen-1 magnetic resonance spectroscopy study of human intracranial tumors.
OBJECTIVE: To investigate the metabolic changes, pathological state and histological types of intracranial tumors with hydrogen-1 magnetic resonance spectroscopy (H-1 MRS). METHODS: Thirteen patients with intracranial tumors were studied with localized proton magnetic resonance spectroscopy (H-1MRS), in vivo. All spectra were obtained with a 2.0 T whole body MR imaging system. RESULTS: All the spectra of these tumors exhibited high ratios of choline (Cho)/creatine (Cr) and Cho/N-acetyl aspartate (NAA), and histologically different tumors showed obvious variations in the metabolite ratios. Significant differences of Cho/Cr ratio were found between meningiomas and astrocytomas by statistical evaluation. The spectra obtained after operation were remarkably different from those before operation. CONCLUSION: H-1 MRS can serve as a non-invasive clinical test for therapeutic and prognostic uses for intracranial tumors. (+info)
(7/1082) NF2 gene mutations and allelic status of 1p, 14q and 22q in sporadic meningiomas.
Formation of meningiomas and their progression to malignancy may be a multi-step process, implying accumulation of genetic mutations at specific loci. To determine the relationship between early NF2 gene inactivation and the molecular mechanisms that may contribute to meningioma tumor progression, we have performed deletion mapping analysis at chromosomes 1, 14 and 22 in a series of 81 sporadic meningiomas (54 grade I (typical), 25 grade II (atypical) and two grade III (anaplastic)), which were also studied for NF2 gene mutations. Single-strand conformational polymorphism analysis was used to identify 11 mutations in five of the eight exons of the NF2 gene studied. All 11 tumors displayed loss of heterozygosity (LOH) for chromosome 22 markers; this anomaly was also detected in 33 additional tumors. Twenty-nine and 23 cases were characterized by LOH at 1p and 14q, respectively, mostly corresponding to aggressive tumors that also generally displayed LOH 22. All three alterations were detected in association in seven grade II and two grade III meningiomas, corroborating the hypothesis that the formation of aggressive meningiomas follows a multi-step tumor progression model. (+info)
(8/1082) Clinical features and outcomes in patients with non-acoustic cerebellopontine angle tumours.
OBJECTIVES: Non-acoustic tumours of the cerebellopontine angle differ from vestibular schwannomas in their prevalence, clinical features, operative management, and surgical outcome. These features were studied in patients presenting to the regional neuro-otological unit. METHODS: A retrospective analysis of clinical notes identified 42 patients with non-acoustic tumours of the cerebellopontine angle. Data were extracted regarding presenting clinical features, histopathological data after surgical resection, surgical morbidity and mortality, and clinical outcome (mean 32 months follow up). RESULTS: The study group comprised 25 meningiomas (60%), 12 epidermoid cysts/cholesteatomata (28%), and five other tumours. In patients with meningiomas, symptoms differed considerably from patients presenting with vestibular schwannomas. Cerebellar signs were present in 52% and hearing loss in only 68%. Twenty per cent of patients had hydrocephalus at the time of diagnosis. After surgical resection, normal facial nerve function was preserved in 75% of cases. In the epidermoid group, fifth, seventh, and eighth nerve deficits were present in 42%, 33%, and 66% respectively. There were no new postoperative facial palsies. There were two recurrences (17%) requiring reoperation. Overall, there were two perioperative deaths from pneumonia and meningitis. CONCLUSIONS: Patients with non-acoustic lesions of the cerebellopontine angle often present with different symptoms and signs from those found in patients with schwannomas. Hearing loss is less prevalent and cerebellar signs and facial paresis are more common as presenting features. Hydrocephalus is often present in patients presenting with cerebellopontine angle meningiomas. Non-acoustic tumours can usually be resected with facial nerve preservation. (+info)