Extra-axial Hodgkin’s lymphoma with bony hyperostosis mimicking meningioma

Adjacent calvarial hyperostosis is commonly used to aid in the radiological diagnosis of a meningioma. While occasionally reported in dural non-Hodgkin’s lymphoma (NHL), adjacent calvarial hyperostosis has not been reported with systemic presentation of Hodgkin’s lymphoma (HL). We report the first patient with systemic HL presenting as an extra-axial mass mimicking meningioma with adjacent calvarial hyperostosis confirmed on CT scan and MRI.     

Non-Dura Based Intaspinal Clear Cell Meningioma

A 34-year-old female patient was presented with leg and hip pain for 6 months as well as voiding difficulty for 1 year. Magnetic resonance imaging revealed a well-demarcated mass lesion at L2-3. The mass was hypo-intense on T1- and T2-weighted images with homogeneous gadolinium enhancement. Surgery was performed with the presumptive diagnosis of intradural extramedullary meningioma. Complete tumor removal was possible due to lack of dural adhesion of the tumor. Histologic diagnosis was clear cell meningioma, a rare and newly included World Health Organization classification of meningioma usually affecting younger patients. During postoperative 2 years, the patient has shown no evidence of recurrence. We report a rare case of cauda equina clear cell meningioma without any dural attachment.     

Primary dural lymphoma mimicking a subdural hematoma

Intracranial marginal zone B-cell lymphoma presenting as a dural-based mass is rare. A 45-year-old woman who had generalized tonic-clonic seizures and speech disturbance for 6 months was referred to our hospital. Radiology suggested a subdural hematoma (SDH). No improvement in the radiological findings or symptoms occurred with conservative follow-up. Therefore, she underwent a craniotomy for drainage of the suspected SDH. Intraoperatively, dural plaque-like thickening was observed, with no SDH, and a biopsy was performed. After histopathological and immunohistochemical studies, a mucosa-associated lymphoid tissue (MALT) lymphoma was diagnosed. The patient underwent radiotherapy with no postoperative complications or recurrence. Early diagnosis and treatment of primary dural lymphoma is important. Histopathological evaluation is necessary for diagnosis. MRI cannot reliably differentiate between SDH and some dural lesions that present as diffuse infiltration. Therefore, these differential diagnoses should be considered.     

Neurosarcoidosis: evaluation with MRI

Clinical studies report a rate of 5% and autopsy results a rate of 25% of brain involvement in sarcoidosis. The aim of this study was to evaluate the role of magnetic resonance imaging (MRI) in the diagnosis of patients with neurosarcoidosis. The MRI brain scans of 22 patients with sarcoidosis were retrospectively reviewed, along with the clinical information that was provided in the request form. All patients had signs and symptoms referable to the head and were examined with gadolinium enhancement. Cranial (facial) nerve paralysis was the most common clinical manifestation identified in 10 patients. A wide spectrum of MR findings was noted: Periventricular and white matter lesions on T2W spin echo images, mimicking multiple sclerosis (46%); multiple supratentorial and infratentorial brain lesions, mimicking metastases (36%); solitary intraaxial mass, mimicking high grade astrocytoma (9%); solitary extraaxial mass, mimicking meningioma (5%); leptomeningeal enhancement (36%). These findings are not specific for sarcoidosis and one must consider appropriate clinical circumstances in arriving at the correct diagnosis. In selected cases with isolated brain involvement, meningeal or cerebral biopsy may be required.     

Dural metastases mimicking meningioma. Case report and review of the literature.

The typical appearance of meningioma on CT and MRI is well known. Particularly in the elderly, the imaging appearance is sometimes considered diagnostic of these benign tumours without histopathological confirmation. However, other more aggressive neoplasms can present with a classical CT and MRI appearance of meningioma, indicating the need for histopathological confirmation wherever possible. We report a case of dural metastases which, on both pre-operative CT and MRI and at surgery, had the typical appearance of a falcine meningioma. Histopathology and immunohistochemistry revealed adenocarcinoma of renal cell origin, and the renal primary was identified on subsequent abdominal investigation. The literature regarding dural metastases is reviewed. To our knowledge, this is the first reported case of a renal carcinoma metastasizing directly to the dura. Although rare, dural metastases can mimic meningioma, and this needs to be considered if conservative therapy or radiosurgery are to be offered to a patient with radiological diagnosis of meningioma.     

Extraosseous multiple myeloma mimicking spinal epidural metastasis

A 42-year-old man presented with a one-month history of upper back pain and a two-week history of progressive spastic paraparesis. Thoracic spinal MRI showed an epidural mass with spinal cord compression at T6–8 but no bony involvement. The patient underwent T6–8 laminectomy for decompression. Lumbosacral MRI and CT scans revealed bony abnormalities on the sacrum and left posterior iliac bone. Immunohistochemical studies confirmed the diagnosis of multiple myeloma (MM). Thus, this patient suffered from extraosseous MM without adjacent bony involvement or distant skeletal involvement.     

Dural cavernous angioma mimicking a meningioma and causing facial pain.

An 18-year-old girl who had severe headaches in the left temporal and facial regions was found to have a small enhanced dural-based parietal convexity mass. On magnetic resonance imaging (MRI), this mass was homogeneously enhanced with "dural tail sign," and was similar to a meningioma. This mass was completely removed surgically, and pathology proved it to be a cavernous angioma without previous hemorrhages. The patient's facial pain was dramatically relieved after surgery. A small dural mass causing severe facial pain is an unusual situation. The lack of hemosiderin in the extra-axial cavernous angioma often leads to the preoperative diagnosis of meningioma.     

Tentorium schwannoma mimicking meningioma: an unusual location

A 60-year-old female was admitted to our clinic complaining of a long-lasting headache. Cranial magnetic resonance imagining examination of the patient revealed a 22x24 mm extra-axial, well-demarcated, mass lesion based on the left tentorium. The patient underwent a craniotomy and the tumor was totally excised with the adjacent tentorium. The histopathological examination of the tumor complied with the diagnosis of schwannoma. The rest of the clinical course was uneventful and the patient was released from the hospital without any neurological deficit. Intracranial schwannomas can rarely originate from atypical dural locations and radiological techniques are not always helpful in distinguishing tentorial schwannoma from tentorial meningioma. We presented a patient with a tentorium schwannoma mimicking meningioma and discussed the current literature.     

Primary low-grade non-Hodgkin's B lymphoma mimicking meningioma

Primary dural lymphomas are rare. Usually they present themselves as diffuse lesions and are infrequently well-delimited. We present a 44 year old male, who was admitted into our Centre after a generalised seizure. Neuroimage studies (CT scan, MRI and angiography) were performed, demonstrating a right hemispheric well-delimited extra-axial mass, being diagnosed initially as meningioma. The patient underwent surgery with radical scission of the mass and dural margins. Histopathological diagnosis was Non-Hodgkin B-Cell lymphoma (marginal B-Cell lymphoma), which nowadays is considered as MALT lymphoma (Mucosa Associated Lymphoid Tissue). Studies directed to establish tumour extension didn't demonstrate the existence of another lesions in the organism.     

Meningeal Supratentorial Hemangioblastoma in a Patient with Von Hippel-Lindau Disease Mimicking Angioblastic Menigioma

Hemangioblastomas are sporadic tumors found in the cerebellum or spinal cord. Supratentorial hemangioblastomas are rare, and those with meningeal involvement are extremely rare and have been reported in only approximately 130 patients. Here, we report the case of a 51-year-old female patient with supratentorial meningeal hemangioblastoma detected 5 years after surgical resection of an infratentorial hemangioblastoma associated with von Hippel-Lindau disease. Patients with von Hippel-Lindau syndrome are at risk for developing multiple hemangioblastomas, with new tumor formation and growth and possible meningeal infiltration. Regular lifelong follow-up in at-risk patients is recommended and should include the differential diagnosis of dural-based tumors such as angioblastic meningioma and metastatic renal cell carcinoma.     

Meningioma in a 20-month-old boy

A 20-month-old boy presented with a intraparenchymal mass in the right frontoparietal area manifesting as complex partial seizure, secondary generalization and left hemiparesis. Magnetic resonance images (MRI) of the brain showed inhomogeneously enhancing mass in the right frontoparietal area which has irregular margin and perilesional edema. Based on the radiological findings, a preoperative diagnosis was an intraaxial tumor, such as pilocytic astrocytoma or dysembryoplastic neuroepithelial tumor. The patient underwent a surgery including frontal craniotomy. The tumor had a partially extreme adherence to the surrounding brain tissue but it showed no dural attachment. Gross-total resection of the tumor was achieved. Postoperative follow-up computed tomography scans showed no residual tumor. The pathological findings confirmed the tumor as a WHO grade I meningioma, transitional type. Nine months after the surgery, follow-up brain MRI showed no recurrence of the tumor, porencephaly in site where the tumor was resected; the patient's symptoms had fully recovered. We report the case of a meningioma in a 20-month-old boy.     

Meningioma in the Lateral Cerebellomedullary Cistern without Dural Attachment

A 59-year-old female presented with headache and dizziness for one year. Magnetic resonance imaging revealed a 52 × 28 mm, well-circumscribed, homogenously enhancing mass lesion without dural attachment located in the left lateral cerebellomedullary cistern. The tumor was excised, and a histological diagnosis was a mixed pattern meningioma of meningothelial and fibroblastic type. A meningioma in the posterior fossa without dural attachment is quite rare. We report a rare case of lateral cerebellomedullary cistern meningioma without dural attachment with literature review.     

Lymphoplasmacyte‐rich meningioma: A convexity mass with regional enhancement in the adjacent brain parenchyma

Lymphoplasmacyte‐rich meningioma (LPM) is a rare, benign variant of meningioma, characterized by massive inflammatory cell infiltration and a variable proportion of meningothelial tumorous elements. Here we report the clinicopathological features of an LPM located at the right frontal convexity in a 37‐year‐old woman. The patient had suffered an initial generalized tonic‐clonic seizure when she was 32 weeks pregnant. The lesion exhibited low intensity on T1‐weighted MRI and high intensity on T2‐weighted images, with surrounding parenchymal edema. The mass exhibited gadolinium enhancement with dural tail signs. Moreover, multiple foci of linear enhancement spreading through the sulci and into the nearby brain parenchyma were evident. At 1 month after parturition, en bloc removal of the mass, the attached dura mater and adjacent brain tissue was performed. Histologically, the mass located in the subdural space was composed of a mixture of B‐ and T‐lymphocytes and plasma cells. Within the mass, multiple small lobules of meningothelial cells showing immunoreactivity for epithelial membrane antigen and vimentin were observed. The inflammatory cells had also infiltrated the subarachnoid and Virchow‐Robin spaces, and the dura mater. The cerebral cortex showed ischemic changes, but no tumor cell invasion. On the basis of these histological features, the lesion appeared to be LPM with an inconspicuous meningothelial component and extensive inflammatory infiltration. This case appears to provide useful information on the pathogenesis of this variant.     

Non-Dural-Based Spinal Meningioma : The First Case Report of a Fibrous Subtype and a Review of the Literature

Spinal meningiomas typically adhere to the dura matter. Non-dural based spinal meningiomas are rare and most are clear cell meningiomas. We report here the first case of a fibrous meningioma with non-dural attachment. The patient was a 49-year-old female, who complained of numbness in the legs and a gait disturbance. Magnetic resonance imaging revealed a 1.7×1.4-cm mass in the C7-T1 intra-dural extramedullary space, showing peripheral gadolinium enhancement without a "dural tail sign". A complete microsurgical resection was performed. The mass was covered with a white membrane but was not adhered to the dura, and its appearance was consistent with a neurilemmoma. The histopathological diagnosis was fibrous-type meningioma. The recovery of the patient was uneventful. No surgical complications and no recurrence of the tumor had occurred at the 6-month follow-up.     

Low‐grade follicular lymphoma in the dura: Rare mimic of meningioma

Lymphomas rarely present as a localized mass within the dura. We report a case of a 72‐year‐old woman, normally fit and well, who presented with a sudden episode of grand mal seizure. Imaging studies showed an extra‐axial mass arising from the dura, with radiologic features characteristic of a meningioma. The mass was surgically excised, and the histologic features were of a grade 1 follicular lymphoma. Analysis using fluorescent in situ hybridization (FISH) demonstrated t(14:18) translocation. A bone marrow aspirate showed focal infiltration of lumbar vertebra by low‐grade follicular lymphoma. Intracranial meningeal involvement by non‐Hodgkin lymphoma usually occurs in the form of diffuse leptomeningeal spread. It is seen in high‐grade lymphomas, often in association with widespread systemic disease. The majority of cases of dural lymphomas reported in the literature have been primary mucosa‐associated lymphoid tissue (MALT)‐type lymphomas. Most of these presented as localized dural masses mimicking meningiomas. Low‐grade follicular lymphoma, either primary or secondarily involving the dura, appears to be an exceedingly rare occurrence.     

Multiple myeloma presenting as solitary mass in the posterior fossa

Intracranial plasma cell tumors are extremely rare and can either be solitary lesions or part of systemic multiple myeloma. We report a 42-year-old woman who presented with a posterior fossa mass and successfully underwent surgical resection, leading to the diagnosis of multiple myeloma. To our knowledge, this is the first reported case of multiple myeloma presenting as a posterior fossa mass lesion. This report highlights the importance of maintaining plasma cell tumor in the differential of intracranial mass with bony involvement. Furthermore, once the diagnosis is established, further work up is critical to evaluate for systemic disease.     

A unique case of isolated thoracic spinal Rosai-Dorfman disease related to IgG4

Rosai-Dorfman disease (RDD) is a rare benign histiocytosis usually characterized by massive cervical lymphadenopathy and systemic manifestations. Extranodal, especially spinal involvement, is extremely rare. Our case was deemed worthy of presentation because it was the first reported isolated case of spinal RDD related to IgG4 and mimicked meningioma clinically and radiologically. A case with an intradural extramedullary mass causing neurological compression findings in the thoracic spinal region and radiologically mimicking meningioma is presented. In the histomorphological examination of the resection material, polymorphonuclear leukocytes in the dura, histiocytes showing emperipolesis, an increase in collagenized fibrous connective tissue, and intense lymphoplasmacytic cell infiltration accompanied by obliterative phlebitis were observed. Immunohistochemically, the histiocytic cells were found to be S-100 protein, CD68, and CD163 positive and CD1a and langerin negative, and more than half of the plasma cells were immunoglobulin-G4 (IgG4) positive. Although rare, RDD or IgG4-related meningeal disease should be considered in the differential diagnosis of dural-based spinal masses that radiologically suggest meningioma. The pathologist should be aware that these two histopathological entities may coexist. To our knowledge, this is the first case of “isolated spinal RDD related to IgG4” reported in the literature.     

非典型性脑膜瘤与良性脑膜瘤MRI征象的对比分析

目的 对比分析非典型性脑膜瘤与良性脑膜瘤的MRI征象特点,提高对非典型性脑膜瘤的认识。方法 回顾性分析经病理证实的37例非典型性脑膜瘤与288例良性脑膜瘤的MRI征象。结果 非典型性脑膜瘤直径>6.5 cm比例、肿瘤呈分叶型比例、瘤脑界面不清晰比例、重度瘤周水肿比例、邻近骨质改变比例均明显高于良性脑膜瘤（P<0.05）。多因素Logistic回归分析显示,肿瘤较大及瘤脑界面不清晰为非典型性脑膜瘤的可能性显著增加,肿瘤大小每增加1.5 cm,非典型性脑膜瘤的概率是良性脑膜瘤的1.507倍,瘤脑界面不清晰为非典型性脑膜瘤的概率是良性脑膜瘤的2.605倍。结论 肿瘤大小及瘤脑界面对于非典型性脑膜瘤与良性脑膜瘤的鉴别诊断具有重要价值。     

Denervation hypertrophy may mimic local tumor spread on magnetic resonance imaging

We report a patient with an extensive paranasal sinus carcinoma. One year after tumor resection, magnetic resonance imaging (MRI) showed swelling of the ipsilateral masticatory muscles with signal increase on T2-weighted images and gadolinium-DTPA uptake, suggestive of local tumor infiltration. However, electromyography, biopsy, and follow-up MRI confirmed denervation pseudohypertrophy of the muscles innervated by the mandibular nerve and excluded tumor recurrence. Muscle denervation and pseudohypertrophy should be considered in the differential diagnosis of appropriate patients with suspected tumor recurrence.     

Primary intracerebral malignant fibrous histiocytoma mimicking a meningioma

We describe herein a patient with primary intracerebral malignant fibrous histiocytoma (MFH) to demonstrate this very rare central nervous system tumor. A 42-year-old male was admitted to our institute with the complaints of headache and speech impairment. Magnetic resonance imaging (MRI) revealed a tumor consistent with meningioma and we decided the surgery. The tumor was excised totally during the initial surgery. Histopathological examination revealed a mesenchymal tumor with an invasion of the adjacent brain and underlying dura mater. On the postoperative 4th month, the follow up MRI showed tumor recurrence at the same location and of similar size. Reoperation was performed and the tumor was again removed gross totally. However, the patient demonstrated a rapidly progressive course leading to death within the first year after the surgery. Two significant points of this case of primary central nervous system MFH are the rarity of its occurrence and its mimicking a meningioma.