Search

Background: Meningioma en plaque represents a morphological subgroup within the meningiomas defined by a carpet or sheet-like lesion that infiltrates the dura and sometimes invades the bone. Differential diagnosis includes fibrous dysplasia, osteoma, and osteoblastic metastasis. This study was conducted to obtain pathological information on patients with meningioma en plaque and to correlate with the surgical management., Methods: A retrospective review of all the adult operative cases at the University Hospital in a seven and a half-year period from July 1, 1990 to December 31, 1997 identified 150 patients who were operated on for intracranial meningiomas. The medical records were reviewed to identify cases of meningioma en plaque. Forty-seven patients had involvement of the sphenoid ridge and 6 of them fulfill the criteria for meningioma en plaque., Results: All 6 patients with meningiomas en plaque were female and had hyperostosis of the sphenoid bone. In 5 of them, the bone was sent for histopathological examination. Four of those had infiltration of the bone by meningioma cells. Proptosis was the most common presentation. Half of the patients presented with visual disturbances that improved after surgery. All patients were operated using a fronto-temporal approach with orbital decompression., Conclusion: All the involved bone should be removed to prevent recurrence. In those cases with involvement of the cavernous sinus and/or the orbital apex, a subtotal but extensive removal combined with bony decompression of the cranial nerves at the superior orbital fissure and optic canal frequently produces good functional and cosmetic results.

Background: Petroclival and foramen magnum meningiomas sometimes encase the vertebrobasilar arterial system. Magnetic resonance imaging can clearly reveal such encasement. The case presented here was of a meningioma involving the lower clivus and the foramen magnum, encasing a lateral segment of the posterior inferior cerebellar artery (PICA), despite the fact that no definitive diagnosis of the encasement of the PICA was made on preoperative radiological examination. End-to-end anastomosis of the PICA was necessary before excision of the tumor., Methods: A 55-year-old woman presented with complaints of headache and numbness of the right upper extremity. Gadolinium diethylene-thiamine-pentaacetic acid enhanced T1-weighted magnetic resonance (MR) images showed a homogeneously enhanced mass lesion involving the lower clivus and the foramen magnum. Direct surgery was then performed, and the lateral medullary segment of the left PICA was found to be encased by the tumor. End-to-end anastomosis was performed using No. 10-0 interrupted monofilament nylon sutures. Total removal of the tumor was performed after completion of the anastomosis. The patient was free of neurological abnormalities and no recurrence of tumor was found during a 2-year follow-up period., Conclusions: Revascularization is sometimes thought to be required for resection of craniospinal meningiomas even when they do not appear to encase the vertebro-basilar arterial system on preoperative MR imaging and cerebral angiograms. In the present case, dissection of the PICA from the tumor was attempted, but was difficult due to tight encasement of the PICA by the tumor.

Background: Spinal metastasis of intracranial meningiomas has rarely been reported. Three out of ten previously reported cases of malignant meningioma metastasizing to the spine had undergone surgical debulking with no neurological improvement. The authors retrospectively reviewed the treatment course of three patients with malignant meningioma metastasizing to the spine who underwent early magnetic resonance imaging (MRI) and radiotherapy without surgical debulking., Case Description: Three patients with intracranial malignant meningiomas underwent multiple resections of intracranial lesions, and developed spinal intradural metastases an average of 64 months (range, 27-102 months) from their initial presentation. All three patients had at least two operations for recurrent intracranial tumors. All had localized back pain with motor weakness, and MRI scans demonstrated spinal involvement. No surgical exploration was performed for the spinal lesions; rather, all patients received steroids and radiotherapy for the spinal lesions. All three patients improved neurologically after the steroid and radiation treatments, and went on to survive from 3 to 18 months., Conclusion: Early MRI should be performed in patients with spinal symptoms and signs after the treatment of intracranial meningiomas. Radiotherapy is an effective palliative treatment for spinal metastases.

In this study 48 patients with histologic grade I and 41 with grade II/III meningiomas were reviewed retrospectively for the occurrence of multifocal tumor masses in relation to recurrence. Regional multicentric tumor masses were increasingly seen in progressive disease with repeated recurrence and occurred significantly more frequently in grade II/III compared to grade I meningiomas. Small microscopic tumor extensions along the subdural space around the tumor bulk, defined as tumor spurs, could be documented as an alternative form of multifocal disease. The occurrence of these spurs was associated with recurrence. In nearly all cases the multifocal disease was limited to the vicinity of the primary or previous tumor site. In three patients with grade III meningiomas however, at recurrence distant tumors could be found. These were interpreted as drop, cerebrospinal fluid and hematogenic metastases, respectively. In these three cases tumor spurs were documented in previous operations. It is concluded that not only primary new growth in a tumor that virtually from the beginning already has a regional multifocal origin, but also the spread of tumor cells along the subdural space forming tumor spurs, as well as distant metastases, plays an important role in recurrent meningioma.

Distant bone metastases in cases of intracranial meningiomas are uncommon. Two patients with meningiomas showing malignant histological features are described, in both of whom bone metastases were observed many years after cranial surgery.

Spinal meningiomas may be primarily extradural, leading to errors in diagnosis and management. Myelographic findings and the microscopic examination of fresh tissue at the time of operation often lead to the conclusion that the tumor is metastatic. Three patients with this type of meningioma have been encountered. Although extensive removal of the tumor was accomplished in each case, the correct diagnosis was difficult to establish at the time of the operation. A second operation was necessary in one patient because the true nature of the tumor was not recognized initially.

A patient presented with a histologically benign intracranial meningioma which, after multiple recurrences, underwent malignant transformation. The patient survived 18 years following initial presentation. Pulmonary metastases were present over the final 8 years. Eleven subtotal resections of the meningioma were performed, including exenteration of the right eye and a thoracotomy. Radiation therapy and chemotherapy were relatively ineffective. The problem and treatment of recurrent meningiomas is briefly reviewed.

A 67-year-old man developed a malignant meningioma of the right lateral ventricle at the trigone, for which he underwent total removal of the tumor and local irradiation. Six months after the operation, a spinal tumor developed and subtotal removal of the tumor was made. The spinal tumor was considered to be a metastasis via the cerebrospinal fluid in view of its histologic identity with the primary tumor, histologic findings of malignancy, absence of von Recklinghausen's disease, and lack of tumor attachment to the dura.

A 56-year-old man, with known metastatic carcinoma of the prostate, presented with a single Jacksonian seizure. Examination revealed a tumor of the falx cerebri which demonstrated many characteristics of a meningioma. Although exceedingly rare, the tumor proved to be a meningeal metastasis of the prostatic adenocarcinoma. The relevant literature is reviewed.