"Pure" Suprasellar Schwannoma Presented with Communicating Hydrocephalus: A Case Report

Schwannoma is a benign peripheral nerve sheath tumor originating from Schwann cells. Most intracranial schwannomas arise from vestibular nerve and schwannoma in the suprasellar region is extremely rare. A 64-year-old man presented with walking disturbance and blurred vision for three months. Lateral hemianopsia in the left eye and brachybasia were observed. Magnetic resonance imaging revealed a suprasellar tumor with strong contrast enhancement associated with communicating hydrocephalus. The cerebrospinal fluid tap test improved gait disturbance. Hypothalamic stimulation test revealed hypo-reaction of GH, FSH and LH. After ventriculo-peritoneal shunting, the tumor was totally removed via a bilateral front-basal approach with a clinical diagnosis of craniopharyngioma. No adhesion was observed between the tumor and surrounding structures such as meninges and brain. The histopathological diagnosis was schwannoma. Here we report a case of suprasellar schwannoma associated with communicating hydrocephalus that has not ever been previously reported, with special reference to its pathogenesis.

Pituitary Glioblastoma: A Case Report

Introduction:

Pituitary adenomas have been the most common sellaturcica tumors. There have been many unusual types of pituitary tumors that might neglect by radiologists and clinicians. One of these tumors would be the malignant glioma.

Case Presentation:

A 62-year-old male has complained from sudden frontal headache, nausea, vomiting, decreased vision, blurred vision and double vision. In skull radiographic, there was an expansion of sellaturcica and a lesion with clear border on T1; heterogeneous; iso - to hypotense; size about 3/5 × 2/5 cm with no surrounding edema that it has homogeneously attracted contrast Lesion, that shown a signal hypointensity on T2 with heterogeneous enhancement. In the coronal sections, the tumor expanded to the suprasellar region and optic chiasmatic that has compressed especially on the left side. Partial tumor resection has conducted. The surgery has done by a transsphenoidal approach. The pathologist has diagnosed a glioblastoma. This diagnosis has confirmed using immunohistochemistry technique.

Conclusions:

There have been many unusual types of pituitary tumors that might neglect by radiologists and clinicians. One of these tumors would be the malignant glioma.

Hard calcified intrasellar schwannoma mimicking pituitary adenoma: a case report and review of the literature

BACKGROUND

Intrasellar location of schwannoma is extremely rare, although intracranial schwannomas are common in the central nervous system. The aim of the present study is to describe a calcified intrasellar schwannoma case.

MATERIALS AND METHODS

We represent a 45-year-old woman who had suffered from headaches; right side facial pain and visual disturbance which had worsen during the last week prior to admission. Physical examinations were normal except for the bitemporal visual field hemianopia which match with perimetry examination. MRI demonstrated an unusual seemingly calcified mass lesion in the sellar region which was mimicking pituitary macro adenoma.

RESULT

Total resection of the tumor achieved through endoscopic transnasal transsphenoidal approach by extracapsular dissection and pathologic examination of the tumor revealed calcified schwannoma.

CONCLUSION

The differential diagnoses of sellar and suprasellar lesions include pituitary adenomas, craniopharyngiomas, meningiomas, and many others. However, schwannoma is not usually included, because the occurrence of schwannoma in the sellar or suprasellar region is extremely rare. Only few cases of intrasellar schwannomas have been reported in the literature, all of which presented a suprasellar extension similar to that of our case. Fascinating surgical point is managing very firm tumor through transsphenoidal corridor which we handle it by very sharp, debulking and extracapsular removal.

Primary intrasellar schwannoma

Intracranial schwannomas commonly arise from the eighth cranial nerve in the cerebellopontine angle. Schwannoma arising in the sella and extending into the suprasellar region is very rare and is easily mistaken for pituitary adenoma. To our knowledge, there have been only 12 previous reports. We present a patient with primary intrasellar schwannoma that clinically and radiologically resembled a pituitary adenoma (PA). Intra-operative findings differed from a PA, as the tumour had a firmer consistency. Gross total excision of the lesion was done via a transethmosphenoidal approach. Post-operatively the patient improved in visual acuity and visual fields. We have reviewed the literature and described the characteristics of such lesions.

Spindle cell oncocytoma of the pituitary gland with follicle-like component: organotypic differentiation to support its origin from folliculo-stellate cells

Spindle cell oncocytoma (SCO) is a rare, non-adenomatous tumor originating from the anterior pituitary gland. Composed of fusiform, mitochondrion-rich cells sharing several immunophenotypic and ultrastructural properties with folliculo-stellate cells (FSC), SCO has been proposed to represent a neoplastic counterpart of the latter. To date, however, SCO has failed to meet one criterion commonly used in histological-based taxonomy and diagnostics; that of recapitulating any of FSCs' morphologically defined developmental or physiological states. We describe a unique example of SCO wherein a conventional fascicular texture was seen coexisting with and organically merging into follicle-like arrangements. The sellar tumor of 2.7 × 2.6 × 2.5 cm was transphenoidally resected from a 55-year old female. Preoperative magnetic resonance imaging indicated an isointense, contrast enhancing mass with suprasellar extension. Histology showed multiple rudimentary to well-formed, follicle-like cavities on a classical spindle cell background; while all the participating cells exhibited an SCO immunophenotype, including positivity for S100 protein, vimentin, EMA, Bcl-2, and TTF-1, as well as staining with the antimitochondrial antibody 113-1. Conversely no expression of GFAP, follicular-epithelial cytokeratin, carcinoembryonic antigen, or anterior pituitary hormones was detected. Ultrastructurally, tumor cells facing follicular lumina displayed organelles of epithelial specialization, in particular surface microvilli and apical tight junctions. This constellation is felt to be reminiscent of FSCs' metaplastic transition to follicular epithelium, as observed during embryonic development and physiological renewal of the hormone-secreting parenchyma. Such finding is apt to being read as a supporting argument for SCO's descent from the FSC lineage.

Primary intrasellar schwannoma: clinical, aetiopathological and surgical considerations

Schwannomas originating within the sella turcica are extremely rare. We describe the clinical, radiological and intraoperative findings of a patient with an intrasellar and suprasellar schwannoma. Gross total tumour removal was performed by a trans-sphenoidal approach. Perivascular or ectopic Schwann cells, lateral nerve plexus within the cavernous sinus, as well as Schwann cells from small nerve twigs of the dura are some of the current histopathological hypotheses for the origin of these lesions.

Spindle cell oncocytoma of the adenohypophysis: report of a case with a 16-year follow-up

Spindle cell oncocytoma (SCO) is a recently described, rare neoplasm of the anterior pituitary. Clinically and radiologically simulating a non-functioning macroadenoma, its eponymous fusiform cells display a non-epithelial phenotype with conspicuous cytoplasmic accumulation of mitochondria. We report a case of SCO retrospectively identified in a biopsy specimen 16 years after transsphenoidal operation of a 48-year-old woman. Presenting symptoms were adynamia and transient decrease of visual acuity. Neuroimaging showed an isointense, enhancing, sellar-centered mass 1.8 cm in diameter without evidence of invasive growth. No postoperative adjuvant therapy was administered. The patient was left with panhypopituitarism, yet no recurrence was seen during follow-up. Initially diagnosed as a null cell adenoma of oncocytic type, repeat immunohistochemistry showed the characteristic coexpression of S100 protein, vimentin, and epithelial membrane antigen. Oncocytic granula stained intensely with antimitochondrial antibody 113-1, and were negative with the lysosomal marker CD68. Anterior pituitary hormones tested negative, and there was no evidence of neuroendocrine differentiation using antibodies to synaptophysin and chromogranin. Few cells stained for glial fibrillary acidic protein (GFAP). SCO has been proposed to represent a neoplasm of folliculo-stellate cells (FSCs). While the dynamic properties of the latter are incompletely characterized, and indeed no specific marker allows for their identification, overlapping features of SCO with look alikes, in particular pituicytoma, point to FSCs being a potential adult stem cell. The favorable outcome of the present case further argues for SCO to be considered a low-grade neoplasm. Moderate tumor size, lack of invasiveness, and low proliferation rate are likely predictors of benign behavior.

Intrasellar and parasellar cellular schwannoma

The complexity of the anatomy of the sella turcica and its surroundings accounts for the large number of pathologic entities that may involve this critical area. Intrasellar and parasellar schwannomas are exceedingly rare; only a handful of true sellar tumors of this nature have been reported in the English literature. These lesions may simulate nonsecretory pituitary adenomas clinically and neuroradiologically. Although benign, complete surgical resection of these tumors is usually difficult because of their size, invasiveness, and rich vascularity. From the histopathologic stand point, those cases lacking typical schwannoma histomorphologic features may pose a diagnostic challenge to the pathologist, especially at the time of frozen section examination, because they may resemble other spindle cell neoplasms more common to that location, such as fibrous meningothelial tumors. We report a case of intrasellar and parasellar cellular schwannoma lacking common and reliable neurilemmomatous features, such as the coexistence of cellular Antoni A and loose Antoni B areas, Verocay bodies, and hyalinized thickened vessels. In addition, features infrequently seen in schwannomas were identified in the specimen, including the presence of psammoma bodies, nuclear optically clear pseudoinclusions, and fine intracytoplasmic melanin-like pigment. Ultimately, the use of immunohistochemistry was necessary to achieve a definitive pathologic diagnosis. Cellular schwannoma expands the pathologic differential diagnosis of spindle cell neoplasms of sellar location that the pathologist should have in mind, especially at the time of frozen section examination. The clinical, histopathologic, and neurosurgical aspects of primary cellular schwannomas of the sella turcica are reviewed.