Giant cauda equina schwannoma with dystrophic calcifications : case report and review of the literature

Giant spinal schwannoma of the cauda equine involving many nerve roots is rare, and ossification is usually not observed in the schwannoma. A 21-year-old man presented with a 12-month history of urinary dysfunction and numbness below the buttocks. Plain radiography showed scalloping of the posterior surface of the vertebral bodies from L4 to the sacrum, and magnetic resonance imaging and computed tomography revealed a giant cauda equina tumor with dystrophic calcification. The tumor was completely removed, with intraoperative neurophysiologic monitoring. Histopathologic examination showed that the tumor was a schwannoma. The patient's postoperative course was uneventful, with urinary function and numbness gradually improving. Although a giant schwannoma accompanied by dystrophic calcification is extremely rare, such a tumor can be removed safely and completely by meticulous dissection and careful neuromonitoring of the cauda equina spinal nerves involved in the tumor.     

Giant cell tumor of the temporal bone with intratumoral hemorrhage

We report a case of hemorrhagic giant cell tumor (GCT) of the temporal bone in a 77-year-old woman. The patient suffered from sudden-onset headache and vomiting associated with left temporal hemorrhage. MRI revealed a left temporal extradural mass lesion expanding to the subtemporal fossa, showing strong hypointensity on T(2)-weighted imaging. Subsequent MRI revealed tumor growth with multiple cystic components at 1-month follow up. The tumor was found to be a GCT associated with recent intratumoral hemorrhage and abundant hemosiderin pigmentation. T(2)-weighted MRI of the GCT strongly supported hemosiderin deposition. Secondary formation of cystic components in the GCT can also reflect prior hemorrhage and indicate the progression of shape modification. A literature review revealed that hemosiderin deposition in this rare entity is not as rare as previously thought and that massive intratumoral hemorrhage may occur.     

Calcified vestibular schwannoma in the cerebellopontine angle

Although vestibular schwannoma is a common tumor in the cerebellopontine angle, calcified vestibular schwannoma is rare. A 59-year-old woman with sudden onset epileptic seizures, was referred to Hokkaido Neurosurgical Memorial Hospital. Neurological examination revealed left Bruns nystagmus, left deafness and left cerebellar ataxia. Brain MRI revealed a mass, about 3cm in diameter, in the left cerebellopontine angle. The mass showed heterogeneous intensity on T1- and T2-weighted and fluid-attenuated inversion recovery (FLAIR) images. Hydrocephalus was seen. On CT scan, the tumor was calcified. Preoperatively, vestibular schwannoma, meningioma, cavernous hemangioma, or thrombosed giant aneurysm were considered as differential diagnoses. The pathological diagnosis was schwannoma. For a calcified mass in the cerebellopontine angle, vestibular schwannoma should be considered in the differential diagnosis to plan appropriate treatment strategies.     

Cystic schwannoma of the brainstem

A rare case of cystic schwannoma occurring in the brainstem in the absence of von Recklinghausen's disease is reported. This appears to be the first case in the literature of a cystic schwannoma ever described in this location. While the exact origin of this tumor in this unusual location remains uncertain, different hypotheses are discussed and the possible origin of this tumor from perivascular elements in the brainstem is seriously considered.     

Giant Ventral Midline Schwannoma of Cervical Spine : Agonies and Nuances

Pure ventral midline giant schwannoma is an extremely rare entity. Spinal intradural extramedullary schwannomas commonly occur posterolateral or anterolateral to the spinal cord. A case of a pure midline ventrally situated giant pan cervical extramedullary schwannoma in an 18-year-old male patient with compressive myelopathy and sphincter involvement is presented. Spinal MR imaging showed a midline ventrally situated extramedullary tumor with severe spinal cord compression extending from clivus to C7 vertebra. It was resected through a posterolateral approach. Histology was consistent with a schwannoma. Post operative MR imaging showed no evidence of the tumor. The radiological features, pathogenesis and surgical strategies in management of these difficult tumors are discussed and the relevant literature is briefly reviewed.     

Occipital lobe epilepsy was presented in a patient with intracerebral schwannoma: a case report and literature review

Schwannoma arising within brain parenchyma is a rare scenario. So far, only 70 cases were reported. We reported a case of intracerebral schwannoma presented with occipital lobe epilepsy, which has never been reported before. A 19-year-old man suffered from intermittent blurred vision and headache. Neuroradiological findings showed a left occipital lesion with cystic and solid components. Histological and electron micrograph features confirmed the diagnosis of schwannoma after the tumor was totally removed. The theories and literature related to this case were reviewed and the possible developmental origin was discussed. We found that this kind of schwannoma is more often in adolescent and young adults.     

Cystic giant prolactinoma in childhood.

In childhood and adolescence, pituitary adenomas are rare and half are prolactinomas. However, cystic giant prolactinoma in prepuberty is extremely rare. In this report, we present a 10-year-old boy with a cystic giant prolactinoma who was treated with two-stage surgery as the tumor was dumbbell shaped. To our knowledge, this is the second reported case of a cystic giant prolactinoma in a prepubertal child.     

Giant schwannoma of the cauda equina: case report and review of the literature

Schwannomas arise from the neoplastic transformation of nerve sheath cells and are considered benign tumors. We report here on a 43-year-old patient seen for radiculopathic pain and loss of sphincter control. Magnetic resonance imaging of the spine revealed a giant intraspinal mass extending from L1 to L5. The patient underwent laminectomy for excision of the solitary mass and histological findings were consistent with schwannoma. Giant schwannoma of the cauda equina is a rare tumor, with variable manifestations.     

Intraspinal dural‐based primary osteoblastoma with aneurysmal bone cyst‐like change

Osteoblastoma is a benign bone‐forming neoplasm that occurs commonly in the posterior elements of the spine and the sacrum. However, so far there has been no report of intradural osteoblastoma described in the literature. We present a unique case of intraspinal dural‐based osteoblastoma with aneurysmal bone cyst‐like change without evidence of vertebral involvement. An 11‐year‐old Chinese girl presented with a 3‐month history of gradually progressive back pain and a weakness of both lower limbs. Thoracic MRI revealed a well‐demarcated subdural mass at the T5 level with heterogeneous enhancement. Histologically, the tumor was found to be attached to the dura and composed of numerous osteoid spicules and trabecular bone with diffusely scattered osteoclast‐type, multinucleated giant cells. Ectactic blood vessels and blood‐filled cystic spaces were also observed. A diagnosis of primary intraspinal dural‐based osteoblastoma with aneurysmal bone cyst‐like change was made. To our best knowledge, this is possibly the first case of primary osteoblastoma arising from meninges. Meningeal osteocartilaginous tumors are rare, with obscure histogenesis. The differential diagnosis of osteoblastoma in unusual locations is difficult and the confirmation of diagnosis should be cautiously made. Awareness of dural‐based osteoblastoma and its histological features is important to avoid a diagnostic pitfall caused by histological similarities to other intra‐craniospinal lesions with osteoid differentiation or bone formation.     

Hemorrhage into cystic vestibular schwannoma following stereotactic radiation therapy

The occurrence of a hemorrhage into a vestibular schwannoma is a rare phenomenon. Several reports, however, indicate a risk profile for a subgroup of patients with vestibular schwannoma which show hypervascularity in the histopathological examination. Cystic formation, large size, mixed Antoni type and anticoagulation therapy seem to enhance the risk of tumor hemorrhage. We report on a patient with a large cystic vestibular schwannoma who died from fatal bleeding into the tumor 15 months following stereotactic radiation therapy. Since hemorrhage seems to be a relevant risk in large cystic vestibular schwannomas, a surgical treatment should be preferred whenever possible.     

Thoracic intradural cystic schwannoma: a case report

Spinal schwannomas are benign tumors arising from spinal nerve root sheaths. These are the most common intradural extramedullary spinal tumors. Schwannomas are mostly solid or heterogeneous solid tumors. Cystic schwannomas are rare lesions. We present a 27-year-old woman with an intradural extramedullary cystic tumor in the lower thoracic region who complained of back pain and walking difficulty. The patient was operated and the tumor was totally removed. The postoperative course was uneventful. The histopathological diagnosis was cystic schwannoma. Differentiation of cystic schwannomas from other cystic mass lesions can be difficult. Magnetic resonance imaging and histopathological findings are important for evaluating these tumors.     

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.     

A huge occipital osteoblastoma accompanied with aneurysmal bone cyst in the posterior cranial fossa

Osteoblastoma is an infrequent benign tumor and skull involvement is extremely rare. The occipital bone is much less frequently involved. We report an unusual case of a huge occipital osteoblastoma with aneurysmal bone cyst in the posterior cranial fossa of a 20-year-old young man. MRI scan and CT three-dimensional reconstruction revealed that the tumor (approximately 8.5 cm x 6 cm x 5 cm) occupied nearly half volume of the posterior cranial fossa. The cerebellum, the forth ventricle and brain stem were compressed remarkably and hydrocephalus was noted. The tumor mass was multiloculated cystic and highly vascular. Excessive bleeding occurred during operation and total removal was achieved. The patient was symptom-free and MRI scan revealed no evidence of recrudescence after a follow-up period of 18 months. Pathological examination revealed that the lesion was a benign osteoblastoma with secondary aneurysmal bone cyst (ABC). ABC constitutes a highly vascular lesion while complete surgical resection is often impeded by excessive intraoperative bleeding. Preoperative embolization may reduce the risk. Despite the benign nature of osteoblastoma, local recurrence after incomplete resection is not rare and malignant transformation during recurrence may occur even after adequate surgery. Our case confirms the findings of previous investigators that if osteoblastoma is removed completely, no recurrence is expected even without adjuvant irradiation and chemotherapy.     

Pleomorphic Xanthoastrocytoma with an Intracystic Hemorrhage : A Case Report and Literature Review

Pleomorphic xanthoastrocytoma (PXA) has been considered as a low grade tumor of adolescents and young adults. Although this tumor often shows cystic component, the hemorrhage within the cyst is extremely rare. The authors report a rare case of cystic PXA with a hemorrhage within the cyst and the mural nodule in the left frontal lobe. A 64-year-old male presented with a week history of the right side hemiparesis. After gross total resection of the tumor, the patient was fully recovered from neurological deficit. It is suggested that this typically benign tumor could be presented with hemorrhage, causing a rapid neurological deterioration. Prompt surgical intervention, especially total removal of the tumor can provide an excellent functional recovery.     

Vestibular Schwannoma Atypically Invading Temporal Bone

Vestibular schwannoma (VS) usually present the widening of internal auditory canal (IAC), and these bony changes are typically limited to IAC, not extend to temporal bone. Temporal bone invasion by VS is extremely rare. We report 51-year-old man who revealed temporal bone destruction beyond IAC by unilateral VS. The bony destruction extended anteriorly to the carotid canal and inferiorly to the jugular foramen. On histopathologic examination, the tumor showed typical benign schwannoma and did not show any unusual vascularity or malignant feature. Facial nerve was severely compressed and distorted by tumor, which unevenly eroded temporal bone in surgical field. Vestibular schwannoma with atypical invasion of temporal bone can be successfully treated with combined translabyrinthine and lateral suboccipiral approach without facial nerve dysfunction. Early detection and careful dissection of facial nerve with intraoperative monitoring should be considered during operation due to severe adhesion and distortion of facial nerve by tumor and eroded temporal bone.     

Giant cranionasal schwannoma

Giant schwannomas concomitantly involving the intracranial and nasal cavities are rare. We report a 22-year-old male patient with a giant schwannoma involving the frontal skull base and extending into the nasal cavity. The patient had a 2-year history of nasal obstruction that was originally misdiagnosed as nasal polyps. A CT scan and an MRI revealed a large cranionasal tumor. Surgery was performed using a coronal incision with a bilateral frontal skull base extradural approach. The tumor originated from the anterior skull base and the dura and nasal mucosa were intact. Histopathology was consistent with a schwannoma. Schwannoma should be listed as part of the differential diagnosis of a cranionasal tumor and the surgical approach should be carefully selected to achieve total resection.     

Cystic sphenoid wing meningioma mimicking astrocytic glioma

In spite of rare incidence, cystic intracranial meningiomas deserve interest due to difficulties in correct preoperative diagnosis. Authors present a case report of a patient with cystic meningioma mimicking astrocytoma. In addition, review of literature is performed.     

Hypopituitarism and amenorrhea-galactorrhea syndrome caused by thrombosis of both internal carotid artery and giant intrasellar aneurysm: case report

Giant intra and parasellar aneurysm with a spontaneous thrombosis of internal carotid artery is rare. We report the case of a 34 years old woman presenting a unique giant sellar and parasellar aneurysm associated with hypopituitarism and amenorrhea-galactorrhea syndrome. Computed tomographic scans and magnetic resonance images were suggestive of a sellar tumor with a cystic component. Digital cerebral angiography showed spontaneous thrombosis of a intrasellar and parasellar carotid artery aneurysm and left internal carotid artery in the neck. A transseptal endoscopic biopsy was done and confirmed a thrombosed aneurysm. No other surgical treatment was required in this patient but permanent endocrinological treatment was necessary.     

Simultaneously occurring vestibular schwannoma and meningioma in the cerebellopontine angle: case report and literature review

Simultaneously occurring multiple primary brain tumors of different histological types are rare, and the coexistence of schwannoma and meningioma in the same cerebellopontine angle (CPA) without neurofibromatosis is extremely rare. A 57-year-old female patient presented with headache, speech disturbance, left facial numbness and deafness in the left ear. Magnetic resonance imaging demonstrated two different tumors in the left CPA. These tumors were not in continuity. The tumors were totally removed through the left suboccipital approach. Histopathological examination revealed that the large tumor was a vestibular schwannoma and the smaller was a meningioma. Neurofibromatosis was not diagnosed in the patient. No recurrence was observed at the end of 9 years after the operation. The simultaneous occurrence of vestibular schwannoma and meningioma in the CPA appears coincidental. This association must be kept in mind if two different tumors are detected radiologically in the same CPA.     

Schwannoma of the oculomotor nerve

A 63-year-old woman presented with an extremely rare oculomotor schwannoma not associated with neurofibromatosis, manifesting as a transient diplopia and ptosis. Magnetic resonance images showed a well-enhanced mass extending from the cavernous sinus to the intraorbital region. Surgical exposure confirmed the tumor originating from the oculomotor nerve in the cavernous sinus. The intraorbital cystic part of the tumor was partially resected to preserve the oculomotor function. This is the first case of oculomotor schwannoma in the cavernous sinus with intraorbital component.