A case of multiple primary tumors of the anterior skull base.

We report a case of synchronous olfactory bulb meningioma and undifferentiated carcinoma of the nose and paranasal sinuses that involved and destroyed the anterior skull base and mimicked intracranial invasion by a carcinoma. The heterogeneity of tissue types in the skull base gives rise to a diverse variety of benign and malignant neoplasms which have totally different prognoses. Synchronous development of benign and malignant primary tumors both originating from and involving the skull base at the same location is very rare and may cause confusion for both the skull base surgeon and neuroradiologist.     

Hyperostotic meningioma with minimal tumor invasion into the skull

A 56-year-old man presented with a meningioma associated with hyperostotic bone containing little tumor cell infiltration. The patient presented with a growing mass on his right forehead and exophthalmos. Computed tomography (CT) taken 4 years previously revealed only hyperostosis without intracranial lesion. Repeat CT revealed an enhanced intracranial mass with overlying diffuse hyperostosis extending extracranially. The tumor and affected bone were widely removed. Histological examination confirmed rhabdoid meningioma in the intracranial and extracranial lesion. However, most of the hyperostotic bone showed no tumor cell infiltration. The cause of hyperostosis associated with meningioma is unclear, but tumor invasion is the generally accepted cause. In this case, hyperostosis occurred without tumor cell infiltration so another mechanism was probably involved. The extracranial extension occurred despite the disproportionately small tumor without global tumor cell infiltration of the bone or bony erosion.     

Epidemiology of intracranial meningioma

Meningiomas are the most frequently reported primary intracranial neoplasms, accounting for approximately 25% of all such lesions diagnosed in the United States. Few studies have examined the risk factors associated with a diagnosis of meningioma with two categories of exposure, hormones (both endogenous and exogenous) and radiation, most strongly associated with meningioma risk. Limited data are also available on long-term outcomes for meningioma patients, although it is clear that the disease is associated with significant morbidity and mortality. Recent legislation passed in the United States (The Benign Brain Tumor Cancer Registries Amendment Act [H.R. 5204]) mandates registration of benign brain tumors such as meningioma. This will increase the focus on this disease over the coming years as well as likely increase the reported prevalence of the disease. The increased emphasis on research dedicated to the study of brain tumors coupled with the advent of new tools in genetic and molecular epidemiology make the current era an ideal time to advance knowledge for intracranial meningioma. This review highlights current knowledge of meningioma epidemiology and new directions for research efforts in this field.     

Brain tumors and plasmin inhibitors

Four different intracranial neoplasms inhibited purified plasmin in an in vitro assay. The greatest inhibition (80%) was observed with extracts of a parasagittal meningioma that had invaded and completely occluded the sinus. Significant inhibition (greater than 40%) was also observed with extracts prepared from a glioma surgically removed from a patient who had suffered three thromboembolic episodes during the preceding several months. Lesser (less than 30%) inhibition was obtained with extracts from two other patients who had no evidence of thromboembolic complications. This report constitutes the first demonstration of plasmin inhibition activity in association with brain tumors. Further studies will be required to test the hypothesis that certain intracranial tumors may escape host antitumor fibrinolytic activity by producing plasmin inhibitors and that plasmin inhibitors may play a role in the thromboembolic complications frequently seen in patients with intracranial neoplasms.     

Primary intraspinal neoplasms in Norway, 1955 to 1986. A population-based survey of 467 patients

A survey of all patients (173 males and 294 females) registered with primary intraspinal neoplasms in the Norwegian Cancer Registry from 1955 through 1986 is presented. Annual age-adjusted incidence rates of new tumors per one million population were three for males and five for females. Altogether, 89% of the tumors were verified histologically. Meningioma was the most common tumor type, followed by ependymoma and neurilemoma. Intraspinal ependymomas accounted for 34.5% of all 223 ependymomas of the central nervous system, whereas only 0.2% of the 3046 glioblastomas were found intraspinally. Patients with intraspinal meningioma had a better life expectancy than those with intracranial meningioma. The 5-year relative survival rate for patients with intraspinal ependymoma was 88.9% in contrast to 24.4% for patients with intracranial ependymoma.     

Mature posterior fossa teratoma mimicking infratentorial meningioma: a case report

Intracranial teratomas are congenital neoplasms mostly diagnosed in the pediatric hood and usually involve supratentorial midline structures. These teratomas, especially those involving the posterior fossa are an uncommon and representing less than 0.5% of all intracranial tumors. We report a case of mature posterior fossa teratoma in an adult patient diagnosed in the 4th decade of life. This lesion was taken for a huge infratentorial meningioma.     

Meningiomas mimicking cerebral schwannoma

A brain tumor with histological features reminiscent of schwannoma with underlying meningioangiomatosis was subjected to electron microscopic and immunohistochemical analysis, which confirmed the neoplasm as a meningioma. This prompted reexamination of a similar tumor, described in a previous publication as a cerebral schwannoma, with identical immunohistochemical techniques. The results obtained favored alteration of this diagnosis to that of meningioma. This experience has led the authors to recommend the use of immunohistochemistry techniques when evaluating unusual intracranial neoplasms.     

Osteomatous meningioma report of two cases

Summary Two rare cases of osteomatous meningioma of the spinal cord are described. The capacity of these neoplasms to produce bone trabeculae represents one of the many potentialities of differentiation of meningioma cells, which may come from neural crest cells. This histogenetic derivation is sustained by the association of a meningioma with a schwannoma in the second case.From a histological diagnostic point of view, osteomatous meningioma must be distinguished carefully from a bone- infiltrating meningioma.     

Primary intraosseous meningioma of the calvaria: analysis of the literature and case report.

Meningiomas are the most common of the benign intracranial neoplasms. They are uncommon as primary or secondary extracranial entities. Of these, the primary intraosseous variant may represent the rarest form. We report the case of a rare primary intraosseous meningioma presenting as a localized, symptom-free supraorbital bony expansion in an 81-year-old female patient and tabulate the previously reported cases of primary intraosseous meningiomas of the craniomaxillofacial region for analysis.     

Intracranial chloroma in hypereosinophilic myelofibrosis

BACKGROUND: Chloroma, also called granulocytic sarcoma, is a localized extramedullary tumor composed of leukemic myeloid cells. It is a rare tumor that can occur in various locations. The association of chloroma with leukemic disease or myeloproliferative disorders is limited to isolated case reports. CASE DESCRIPTION: We report a case of intracranial chloroma in an elderly man with myelofibrosis and progressive hypereosinophilia. The presence of leukemic cells within his pleural aspirate suggested an incipient acute leukemic state. CONCLUSION: We report the first case of intracranial chloroma associated with hypereosinophilia developing in the course of myelofibrosis. The significance of hypereosinophilia in predicting the likelihood of development of central nervous system chloroma and acute leukemia in a patient with myelofibrosis needs further evaluation.     

Production of collagenase and inhibitor (TIMP) by intracranial tumors and dura in vitro

The production of collagenase and collagenase inhibitor (TIMP) by various intracranial tumors (25 meningiomas, eight gliomas, seven metastases, four pituitary adenomas, and five others) was studied in short-term organ culture. While meningiomas produced negligible amounts of collagenase, two metastatic carcinomas of bronchial and breast origin produced significant amounts of the enzyme. Cultures of dura from an invasive meningioma and of bone invaded by a meningioma also produced collagenase. In varying amounts, TIMP was detected in culture media from most of the tumors studied; invasive tumors tended to produce less TIMP than noninvasive tumors. The results are discussed in relation to current views on tissue degradation and mechanisms of tumor invasion.     

Metastasis in meningioma

Summary Meningioma is a neoplastic growth originating from the leptomeninges. Although meningiomas are usually benign, malignant meningiomas with distant metastases occur infrequently. There is little precise information in the literature regarding the frequency of metastases in meningiomas; their incidence has been vaguely reported to be less than 1 per 1,000. Furthermore, most of the previous studies have also included haemangiopericytomas which most recent authorities do not consider meningiomas. In our experience with the management of 396 meningiomas over the past 18 years, 7 meningiomas were classified as malignant by defined histological criteria. After initially presenting as solitary intracranial neoplasms, three of the malignant meningiomas metastasized to extracranial tissues. Collectively, the metastases involved the vertebral bodies, liver, pelvis, long bones, and the spinal cord. This confers an incidence of metastasis of 0.76% when considering all the meningiomas, and an incidence of approximately 43% when considering only malignant meningioma; both percentages are significantly higher than reported previously. This high incidence of metastasis in the malignant meningioma indicates a worse prognosis than formerly assessed and also characterizes the malignant meningioma as a primary central nervous system neoplasm with one of the highest rates of metastasis. In addition, when malignant meningioma is classified by following strict criteria, the risk of metastasis in the ensuing clinical course can be predicted with a higher reliability.     

脑膜瘤的MRI征象与病理分级的关系

目的：研究脑膜瘤的MRI表现及其病理学意义。方法收集57例脑膜瘤标本,分析其MRI征象（包括肿瘤的形态、信号及强化特点、瘤-脑组织界面、瘤周水肿及有无周围组织结构受侵等）,同时观察脑膜瘤的病理分级,对所得的资料进行统计学分析。结果脑膜瘤的形态、信号均匀度、强化均匀度、瘤-脑组织界面、瘤周水肿程度及有无周围组织结构受侵等影像学表现与脑膜瘤的良恶性具有相关性（P＜0.05）。结论脑膜瘤的MRI征象具有一定的特征性,在一定程度上可以反映脑膜瘤的病理特点,达到帮助预测肿瘤良恶性的目的,从而为临床合理选择治疗方案及预后评估提供更大帮助。     

Problems in the management of intracranial meningiomas.

Meningiomas account for approximately 15-20% of all brain tumors, and are the most common benign intracranial tumor. These neoplasms develop from cap cells in the arachnoidea; thus, they can be found anywhere that dura mater exists. Meningiomas are usually diagnosed in middle age, and are significantly more frequent in females than in males. Atypical and anaplastic malignant forms also exist. Some types of meningiomas are difficult to manage and require special considerations. The first-line therapy for meningioma is surgery aimed at total excision; however, limitations of surgery must be fully evaluated in order to achieve better results. Conventional radiotherapy and gamma-knife radiosurgery can be used as adjuvant therapeutic modalities under certain conditions. The issues that we consider important in the management of intracranial meningiomas can be discussed under the headings of diagnosis, surgery, multiplicity, pathology, and recurrence.     

Non-Hodgkin's lymphoma, renal carcinoma, and meningioma. A clinical case

Some second malignant neoplasms are increasingly being observed following NHL and a considerable amount of data has accumulated in the literature. The authors describe a case of 65-year old male who presented with submandibular adenopathy. Results of a biopsy of the mass surgically removed revealed low grade non-Hodgkin lymphoma. During the staging workup, a meningioma and a renal cell adenocarcinoma (RCC) were unexpectedly discovered and successively resected. The patient is currently alive with no evidence of metastatic diseases 12 months after diagnosis of non-Hodgkin's lymphoma (NHL), 10 months after meningioma resection and 8 months after RCC resection. The possibility of an underlying pathologic mechanism predisposing to multiple tumours should be considered. RCC and central nervous system (CNS) neoplasms are among second malignancies with higher incidences in non-Hodgkin lymphoma patients whereas with specific regard to meningioma, one of the most common benign intracranial tumours that sometimes shows biological aggressiveness and malignancy, we have currently no data in the literature. Increased risks for several malignancies occur late in the NHL follow-up period and are largely confined to patients receiving either radiation therapy or chemotherapy. On the other hand, increased risks for renal cancer have also been reported at less than one year after diagnosis of NHL and are present in all treatment subgroups (radiation therapy, chemotherapy, other-no treatment). Increased risks for CNS malignant neoplasms have also been reported at less than one year. The authors review the pathogenic significance of this case report neoplasms association in the light of the various explicative hypothesis of this concurrence. Possible immune mechanisms associated with these neoplasm are particularly pointed up.     

Non-functional recurrent pituitary adenoma with intracranial metastasis–Pituitary carcinoma: A case report and review of the literature

IntroductionPituitary carcinomas are rare, with only a few case reports to date. We present a null cell type non-functioning pituitary carcinoma (NFPC) with intracranial metastases and a review of the literature.Case reportA 56-year-old male with a history of an aggressive pituitary adenoma was admitted. Initial MRI highlighted a large intracranial mass with leptomeningeal involvement, simulating meningioma. Based on his previous pathology report of the sellar mass, a diagnosis of null cell type non-functioning pituitary carcinoma has been made.ConclusionsAn aggressive recurrent pituitary tumor with suprasellar and/or cavernous sinus invasion is the main characteristics of the NFPC. Single or multiple enhancing dural-based mass(es) mimicking meningioma is the most common MRI finding. The proof of malignancy is the same histopathological features of the recurrent aggressive pituitary tumor in the metastases. The histology alone is not distinctive in terms of malignancy. Most patients require a combined surgery, radiotherapy and chemotherapy.     

Cystic meningioma. Case report and literature review

BACKGROUND: Cystic meningioma is a rare variety of meningioma. It represents 1,6 to 10% of intracranial meningiomas, the authors report a case of intracranial cystic meningioma with a review of literature. CASE REPORT: A 46-year-old female presented with left parietooccipital headache followed by right side hemiparesis. CT scan brain showed a left parietal tumor with double solid and cystic components thought to be glioma or metastasis preoperatively. At surgery the extraaxial solid and cystic lesion had a well defined capsule that could be easily separated from the perilesional cortical surface. The tumor was totally removed. The histological study showed a cystic meningioma. CONCLUSION: Cystic meningioma is an uncommon tumor that should be considered in the differential diagnosis of brain tumors with a cystic component.     

Intracranial follicular dendritic cell sarcoma. Case report

Intracranial occurrence of follicular dendritic cell (FDC) sarcoma, a rare tumor derived from dendritic cells of the lymphoid follicle, has not yet been described. Therefore, the case of a 53-year-old man presenting with an intracranial mass invading the clivus is reported. The diagnosis of FDC sarcoma was confirmed by immunohistochemical staining for dendritic cell markers, that is, CD21, CD23, and CD35. Due to some similarities with meningioma, intracranial FDC sarcoma might be an underdiagnosed disease.     

Meningioma with meningioangiomatosis: a condition mimicking invasive meningiomas in children and young adults: report of two cases and review of the literature.

Meningioangiomatosis is a malformative meningovascular proliferation that occurs sporadically and in patients with neurofibromatosis type 2. Its histologic features of perivascular proliferation of elongated fibroblast and meningothelial cells trapping islands of gliotic cortex may be erroneously interpreted as invasion when an overlying meningioma is present. We report two cases of meningioangiomatosis associated with meningioma and review the literature on the subject for a total of six cases. The age of patients ranged from 9 months to 33 years. All cases were single lesions, and none had clinical evidence of neurofibromatosis type 2. Meningiomas in children have been regarded as having more aggressive behavior than their adult counterparts, with more frequent invasion of the underlying brain. The lack of correlation between brain invasion and recurrence observed in series of meningiomas in young patients may suggest that some of these lesions are meningioangiomatosis associated with meningioma rather than invasive meningiomas.