Immunohistochemical study of granular cell tumors of the neurohypophysis

Hypothalamic Endocrine Tumors: An Update

The hypothalamus is the site of synthesis and secretion of a number of endocrine peptides that are involved in the regulation of hormonal activity of the pituitary and other endocrine targets. Tumors of the hypothalamus have been recognized to have both structural and functional effects including hormone hypersecretion. The classification of these tumors has advanced over the last few years, and biomarkers are now available to classify these tumors and provide accurate structure-function correlations. This review provides an overview of tumors in this region that is critical to metabolic homeostasis with a focus on advances in the diagnosis of gangliocytomas, neurocytomas, and pituicytomas that are unique to this region.

Clinical and imaging features of granular cell tumor of the neurohypophysis: A retrospective analysis

The aim of this study was to explore x-ray computed tomography (CT) and magnetic resonance imaging (MRI) characteristics specific to granular cell tumors (GCTs) of the neurohypophysis.The clinical and imaging data of 6 patients with operation-proven GCTs of the neurohypophysis were analyzed retrospectively.There were 6 patients with GCTs of the neurohypophysis confirmed pathologically. Five of the tumors were purely suprasellar lesions distinct from the intrasellar pituitary gland. One tumor was both intra- and suprasellar. Solid tumors were hyperattenuated and enhanced homogeneously on CT, while showing isointensity on T1WI and heterogeneous hypointensity on T2WI, with homogeneous (4/5) or inhomogeneous (1/5) enhancement. The cystic tumor showed hypointensity on T1WI and hyperintensity on T2WI, with ring enhancement. "Star-like crack sign" was seen in 2 larger solid cases. Calcification was absent in all cases.Well-circumscribed intra and/or suprasellar masses, hyperattenuated and homogeneously enhancing on CT, hypointensity on T2WI, rarely seen calcification, should arouse suspicion of GCTs of the neurohypophysis.

Sellar and suprasellar granular cell tumor of the neurohypophysis: A rare case report and review of the literature

Granular cell tumors of the neurohypophysis are rare tumors with a WHO grade of I. Symptomatic tumors are even more rare. In this case, we present a 50-year-old patient with a sellar and suprasellar granular cell tumor of the neurohypophysis, who reported headaches, blurred vision and unsteady gait. CT imaging showed a sellar and suprasellar mass approximately 2.9 cm in diameter with clear boundaries. Histologically, the tumor lacked any obvious atypia and contained densely arranged polygonal tumor cells with abundant granular eosinophilic cytoplasm. Staining for Alpha-1 AntiChymotrypsin (AACT), TTF-1 and PAS was diffusely positive, and S-100 staining was focally positive in the tumor cells. CD34, CK, EMA, GFAP and HMB45 staining were negative. The Ki-67 index was < 1%. According to these findings, the tumor was diagnosed as a symptomatic granular cell tumor of the neurohypophysis. We suggest that identifying the location of the tumor with imaging is helpful for understanding the granular cell tumor of the neurohypophysis. Prompt diagnosis and treatment are critical for patients.

Extent of surgical resection and tumor size predicts prognosis in granular cell tumor of the sellar region

BACKGROUND

Rarely, granular cell tumor (GCT) occurs in the sellar region. The natural history of this clinical entity is not well known. This study sought to determine the clinical features and long-term outcome of GCT of the sellar region.

METHODS

Institutional databases, the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database, and PubMed/EMBASE were searched for GCT of the sellar region. Patient-level data were extracted where available, including age, sex, symptoms, tumor size and location, presumed diagnosis, surgical approach and result, subtotal resection (STR) and gross-total resection (GTR), use of radiation, and outcome. The primary endpoints of recurrence and survival were determined.

RESULTS

A total of 141 cases were analyzed. The mean age at diagnosis was 48.9 (SD 15.3) with a female predominance (sex ratio 1.49:1). Almost all patients experienced either or both neurological and endocrine symptoms. The most common pre-operative diagnosis was pituitary adenoma. Approximately 60% of patients were treated with surgery, 57.7% with a craniotomy, and 39.7% with a transsphenoidal approach. The 5-year overall survival (OS) was 84.7% (standard error, SE 4.2). Patients with tumors less than 2.5 cm experienced a greater 5-year OS (100.0%) than patients with tumors 2.5 cm or larger (74.0%, SE: 11.7), (Mantel-Cox, p = 0.024). GTR resulted in a greater 5-year OS (95.7%, SE 4.3) than STR (88.8%, SE 5.5) and no surgery or biopsy alone (75.0%, SE 15.3) (Mantel-Cox, p = 0.016). The use of radiation therapy did not improve OS. The 5-year progression-free survival rate was 80.8% (SE 9.2).

CONCLUSIONS

Granular cell tumor of the sellar region is a relatively benign neoplasm with neurological and endocrine clinical manifestations. Surgical resection is appropriate for management. Tumor size and extent of resection influence overall survival.

Symptomatic Granular Cell Tumor Involving the Pituitary Gland in a Dog: A Case Report and Review of the Literature

A granular cell tumor involving the pituitary gland, optic chiasm and ventral pyriform lobes was discovered in a 12-year-old Labrador Retriever. Clinical signs included acute blindness, seizures, ataxia, weakness, and behavioral changes. The diagnosis was established by histopathologic and ultrastructural examination of neoplastic tissues collected at necropsy. Granular cell tumors involving the central nervous system are well documented in humans but rarely have been described in dogs. The location of the neoplasm and the clinical symptoms seen in this dog closely parallel those of a rare syndrome in humans commonly described as symptomatic parasellar or pituitary granular cell tumors. The cell of origin for these tumors is still highly debated, and attempts to characterize human granular cell tumors through immunohistochemistry have produced conflicting results. An immunohistochemical profile of this neoplasm revealed focal positive staining for vimentin with a lack of staining for neuron-specific enolase, glial fibrillary acidic protein, S-100, and synaptophysin. All neoplastic cells were strongly positive with the periodic acid-Schiff reaction.

Pituicytoma, spindle cell oncocytoma, and granular cell tumor: clarification and meta-analysis of the world literature since 1893

BACKGROUND AND PURPOSE

Pituicytoma, SCO, and GCT are poorly understood entities with confusing nomenclature and undetermined imaging characteristics. Our purpose was to confirm published cases of pituicytoma, SCO, and GCT with the newest 2007 World Health Organization criteria and elucidate imaging findings that distinguish these tumors from common entities such as pituitary adenoma.

MATERIALS AND METHODS

A literature search identified 145 published cases (81 GCTs, 48 pituicytomas, and 16 SCOs). Case diagnoses were blindly reviewed by a neuropathologist according to the latest WHO criteria, resulting in 112 pathologically documented cases (64 GCTs, 35 pituicytomas, and 13 SCOs). Imaging illustrations from proved cases were reviewed to determine location, configuration, attenuation and signal intensity, and enhancement characteristics.

RESULTS

Only pituicytomas presented as purely intrasellar lesions (7/33). Most GCTs were purely suprasellar (28/45). All SCOs were both intra- and suprasellar (13/13). Twenty-five percent of pituicytomas (6/22) and GCTs (7/30) appeared separate from the pituitary gland. All SCOs were infiltrating. Seventy-nine percent of entities appeared isointense to brain on T1-weighted image (34/43). Seventy-four percent of pituicytomas enhanced homogeneously (14/19). Twelve of 23 GCTs and 5/7 SCOs enhanced heterogeneously. Most GCTs were hyperattenuated to brain on CT (18/20). Eleven of 13 cases enhanced homogeneously. Visual disturbances were common symptoms for all entities (67/112). Diabetes insipidus was rare (4/112).

CONCLUSIONS

Pituicytoma may be considered for purely intrasellar masses that are clearly separate from the pituitary gland. GCT should receive consideration for purely suprasellar lesions that are hyperattenuated to brain on CT. SCO should be considered for infiltrating pituitary masses with a mixed intra- and suprasellar location. A history of diabetes insipidus helps to exclude these tumors.

Granular cell tumour of the neurohypophysis: a rare sellar tumour with specific radiological and operative features

Symptomatic granular cell tumours of the neurohypophysis are rare sellar lesions. Preoperative prediction of the diagnosis on the basis of radiological appearance is useful as these tumours carry specific surgical difficulties. This is possible when the tumour arises from the pituitary stalk, rostral to a normal pituitary gland. This has not been emphasized previously.

Pituicytoma incidentally found at autopsy

Pituicytoma is a rare benign neoplasm, occurring in the sellar and suprasellar regions. Reported herein is a case of asymptomatic pituicytoma, discovered at autopsy, in a 54-year-old Japanese woman. This is the first case report of pituicytoma, found incidentally at autopsy (incidentaloma), in which whole-mounted sections are available for histological and immunohistochemical studies. Grossly, the bisected pituitary gland revealed a round, white to light tan, 7 mm-diameter nodule. Microscopically, whole-mounted sections revealed a well-circumscribed nodule with no fibrous capsule, located mainly in the neurohypophysis and partially compressing the adenohypophysis. The tumor was composed primarily of bipolar, occasionally unipolar, cells with syncytial fibrillary cytoplasm, arranged in short curvilinear fascicles and/or storiform patterns. Unusual histological features were seen, which included a few groups of large pleomorphic tumor cells with abundant, glassy, eosinophilic cytoplasm, occasionally associated with multinucleated giant tumor cells, and scattered Herring bodies within the tumor. Immunohistochemically, the tumor showed diffuse strong expression of glial fibrillary acidic protein, S-100 protein, and vimentin. Epithelial membrane antigen immunoreactivity was focally observed, mainly in the large tumor cells. Distinction from other intrasellar tumors (granular cell tumor and pilocytic astrocytoma) is important. Because the immunohistochemical profiles of these tumors are similar, histological findings are crucial for distinction.

Granular cell tumor of the neurohypophysis: report of a case with unusual age presentation

Granular cell tumor (GCT) usually occurs as a solitary, small, nodular tumor and rarely grows to a sufficient size to present symptoms. The tumor is more prevalent in female adults. The authors report a case of an 8-year-old boy with GCT of the neurohypophysis presenting with central precocious puberty. Few cases of symptomatic GCT have been reported in the literature, none of them in a patient in the first decade of life. Clinical picture, histopathological features, and histogenesis of GCT of neurohypophysis are discussed.

Granular cell tumor of the pituitary fossa

Although granular cell tumors are relatively common in the head and neck, symptomatic granular cell tumors of the neurohypophysis are extremely rare. Ophthalmologic symptoms are most common, followed by endocrinologic manifestations. We report a case of a granular cell tumor of the pituitary fossa that was surgically treated. The clinical manifestations, radiographic appearance, and surgical management of granular cell tumors of the pituitary fossa are reviewed, as well as the unique histopathology and electron microscopy of this uncommon neoplasm.

Giant intracranial granular-cell tumor arising from the abducens

We present a case of an adolescent with a giant intracranial granular-cell tumor, who presented with diplopia and worsening visual acuity. The tumor measured 8.2 cm at the maximum diameter and occupied the right middle cranial fossa, with intrasellar and suprasellar involvement. It was composed of solid nests of oval or polygonal eosinophilic cells with a focal pseudo-papillary configuration. Pituitary macroadenoma was suspected from examination of the intraoperative frozen section, but immunohistochemical and ultrastructural findings were consistent with granular-cell tumor, and they suggested the origin to be the peripheral nerve sheath. Considering that abducens palsy was the first clinical manifestation, the tumor was thought to arise from abducens. From histological findings (focal cellular spindling, mitotic activity and a relatively high Ki-67 labeling index [10.1%]) and according to Fanburg-Smith's criteria, the tumor was suspected to have low-grade malignant potential. Granular-cell tumor should be included in the differential diagnosis of parasellar tumors, even in young patients or patients with large lesions. Both immunohistochemical and electron microscopic studies are essential for diagnosis.

Granular Cell Variant of Atypical Fibroxanthoma

We report a case of atypical fibroxanthoma of the ear in which the dominant part of the tumor has granular cell appearance. Areas identical to conventional atypical fibroxanthoma were present only at the lateral infiltrating borders. Histologically the granular cells resembled those of the classical granular cell tumors but exhibited significant pleomorphism and a high mitotic rate. Immunostains for vimentin, CD68 and NK1/C3 were positive but for S-100, HMB-45, myogenic and epithelial markers were negative. The predominance of the granular cells in an atypical fibroxanthoma supports the concept that a small subset of tumors with granular cell phenotype are of nonneural origin.

Acromegaly associated with a granular cell tumor of the neurohypophysis: a clinical and histological study. Case report

Acromegaly is usually caused by a growth hormone (GH)-secreting pituitary adenoma, and hypersecretion of GH-releasing hormone (GHRH) from a hypothalamic or neuroendocrine tumor accounts for other cases. The authors report on the unusual association of acromegaly with a granular cell tumor of the neurohypophysis. A 42-year-old woman with a 10-year history of acral enlargement, headache, and menstrual abnormalities was referred to our department for a suspected GH-secreting pituitary adenoma. The patient's basal GH levels were mildly elevated at 4.8 microg/L, were not suppressed in response to an oral glucose tolerance test, and increased paradoxically after administration of thyrotropin-releasing hormone. The patient's insulin-like growth factor-1 (IGF-1) level was elevated at 462 microg/L, whereas a magnetic resonance image of the sella turcica revealed an intra- and suprasellar lesion that was compatible with a diagnosis of pituitary adenoma. A transsphenoidal approach to remove the lesion, which was mainly suprasellar, was successful during a second operative attempt, resulting in the clinical and biochemical regression of the patient's acromegaly. Four months postoperatively, the patient's basal GH level was 0.9 microg/L and her IGF-1 level was 140 microg/L. Histological analysis of the operative specimen demonstrated a granular cell tumor of the neurohypophysis, which when stained proved negative for pituitary hormones and GHRH. This case represents the first reported association between a granular cell tumor of the neurohypophysis and acromegaly. Granular cell tumor of the neurohypophysis could be added to the restricted list of neoplastic causes of acromegaly secondary to hypersecretion of a GH-releasing substance.

A case of atypical granular cell tumor of the neurohypophysis

A case of granular cell tumor (GCT) arising in the neurohypophysis of a 63-year-old woman is reported. The tumor consisted of ovoid, polygonal or spindle-shaped cells in a sheet-like or fascicular arrangement. Its abundant cytoplasm contained granules positive for diastase-resistant periodic acid-Schiff reaction. Ultrastructurally, the tumor cells contained numerous polymorphic lysosomes of various densities. Immunohistochemically, the tumor cells were positive for S-100 protein, glial fibrillary acidic protein and Leu7, suggesting that the tumor originated from pituicytes that were thought to be modified astrocytes in the neurohypophysis and its stalk. The granular cells showed nuclear atypia, pleomorphism and increased mitotic activity. Therefore, the present tumor was considered as a histologically atypical GCT. Interestingly, proliferating cell nuclear antigen, Ki-67 and p53 were stained in a few tumor cells of this case. These findings indicate that the present tumor had a malignant potential.

The human hypothalamo-neurohypophysial system in health and disease

The present paper reviews the changes observed in the human supraoptic (SON) and paraventricular (PVN) nuclei, and their projections to the neurohypophysis, median eminence and to other brain areas in health and disease.

Granular cell tumor of the pituitary stalk

A 52-year-old woman, who had been treated for Parkinson disease for 2 years, was found to have a suprasellar granular cell tumor. The clinical and pathological features, as well as some of the nosologic problems of this rare tumor of the neurohypophysis are briefly discussed.

Symptomatic granular cell tumor of the pituitary gland: case report and review of the literature

OBJECTIVE AND IMPORTANCE

The posterior pituitary lobe is rarely the site of symptomatic primary tumors. The most common lesions arising from the neurohypophysis and the pituitary stalk seem to be granular cell tumors (GCTs), of which only 42 symptomatic cases have been reported. Here we present an unusually well-documented case of a GCT, which has implications for the differential diagnosis of sellar masses.

CLINICAL PRESENTATION

A 75-year-old woman presented with decreased visual acuity, visual field loss, and a 2-year history of progressive vertigo and headaches. Neuroradiological studies showed a supra- and intrasellar, 25 x 20-mm mass, containing calcifications, that compressed the optic chiasm and extended into the third ventricle.

INTERVENTION

The tumor was subtotally resected through a transsphenoidal approach. The tumor was tough and vascular and could not be suctioned. Histological examination revealed a typical GCT. The postoperative course was uneventful. Residual tumor was treated with fractionated radiation therapy. Ophthalmological testing 10 months after surgery showed a slight improvement in the visual symptoms.

CONCLUSION

Tumor calcifications in computed tomographic scans do not exclude a GCT. The diagnosis requires histological confirmation. Surgical removal by the transsphenoidal approach is the therapy of choice, as for other sellar tumors. Radiation therapy may be advisable after subtotal resection. Our literature review suggests the possibility of gender-related tumor biology in GCTs.

Granular-cell tumours: an immunohistochemical study

The granular cell tumour (myoblastoma, Abrikosoff's tumour) and the congenital epulis in newborns (Neumann tumour) are two lesions rarely found in the oral cavity, whose histogenetic origin is highly controversial. This work analyses using immunohistochemical techniques 15 cases of myoblastomas and two of congenital epulis with different mono- and poly-clonal antibodies. Positive immunostaining was found for S-100 protein and neuron-specific enolase in all the cases of myoblastoma, and for vimentin and carcinoembryonic antigen in some cases. No immunoreactivity was observed for any of the other 13 antibodies used in congenital epulis.

Granular cell tumor expressing myogenic markers in the prostate

A granular cell tumor in the prostate of a 72 year old male is reported. The tumor nest was composed of large polygonal tumor cells, possessing cytoplasmic eosinophilic granules which were positive with PAS stain and resistant to diastase digestion. Immunohistochemically, most tumor cells were strongly positive with anti-alpha-smooth muscle actin and -neuron specific enolase antibodies. Only a few scattered tumor cells were reacted with anti-S-100 protein antibody. These findings might suggest smooth muscle differentiation of this case, and provide an additional insight into the histogenesis of granular cell tumors, especially in their heterogeneity.

Cranial granular-cell tumor of the trigeminal nerve. Case report

Granular-cell tumors are exceedingly rare neoplasms in the central nervous system. Their histogenesis has been a subject of longstanding controversy but substantial findings support the current theory of a Schwann cell origin. Other recent histopathological studies point to an astrocytic origin in those tumors which arise from the cerebral hemispheres. A case of a granular-cell tumor arising from the trigeminal nerve is described. The origin, clinical course, radiological features, and treatment of such unusual intracerebral tumors are discussed.

Granular cell tumor of the pituitary stalk. Case report

The case is described of a granular cell tumor of the pituitary stalk in a 40-year-old woman with secondary amenorrhea. A computerized tomography scan showed a large contrast-enhancing mass, and T1-weighted magnetic resonance images demonstrated a tumor isointense to the brain parenchyma with nonhomogeneous enhancement after intravenous administration of gadolinium diethylenetriamine penta-acetic acid. Histopathological examination, especially immunocytochemical and electron microscopic studies, showed elements supporting an astrocytic origin for this type of tumor, a hypothesis advanced by many authors but still controversial.

Granular cell change in smooth muscle tumours of skin and soft tissue

Nine smooth muscle tumours, arising at a variety of sites and showing granular cell change of their cytoplasm, have been studied morphologically and immunohistochemically. The age of the patients ranged from 6 to 78 years (median 42 years); seven patients were female. Two tumours each arose in the dermis or subcutaneous tissue while the other five cases were situated in deeper soft tissue. Three of the lesions arose in the lower limbs, two in the pelvis and one each in the regions of the elbow, shoulder, breast and buttock. Follow-up in eight patients was available and revealed local recurrence in three and pulmonary metastases in two cases. All cases showed at least focally the light microscopic features of a smooth muscle tumour and demonstrated moderate to strong positivity for alpha-smooth muscle actin. Five were also HHF-35 positive and three were desmin positive. Noteworthy was strong positivity for the 'melanoma associated' antigen NKI/C3 in all cases. Six cases stained also weakly positive for NSE, but all were S-100 protein negative. The former is not specific but is the most reliable marker of lesions showing granular cell change. Granular cytoplasmic change represents simply a cytological phenotype, apparently representing a characteristic metabolic alteration, not exclusively associated with Schwann cell tumours. Tumours containing granular cells are best classified according to their line of specific cellular differentiation if possible.

Aging and the human pituitary gland

Pituitary glands obtained at autopsy from 41 men (90 to 97 years old) and 45 women (90 to 98 years old) were studied histologically and immunohistochemically to determine the age-related alterations. Pituitaries from patients 30 to 39 years old (48 cases) and 60 to 89 years old (187 cases) were also studied and served as controls. Interstitial, perivascular fibrosis was seen in 88% of the aged adenohypophyses and, although significantly more intense than that in those of the fourth decade of life (P < 0.001), was similar to that noted in those of the seventh to ninth decades. Pituitaries of men were significantly more fibrotic than were those of women (P < 0.05). In proportion to the extent of fibrosis, the number of somatotrophs decreased in the lateral wings, whereas other cell types did not change quantitatively. Small deposits of amyloid and of iron were detected in seven and three cases, respectively. Squamous metaplasia in cells of the pars tuberalis was noted in 29%. The incidence of "basophil invasion" (the presence of corticotrophs in the posterior lobe) was 30%, a figure similar to that in younger controls. Granular cell tumorlets were detected in four aged neurohypophyses (5%), a frequency similar to that in control glands. Pituitary adenomas (two null cell, two lactotroph, and one corticotroph adenomas) were found of three men and two women in the study group. This 9% incidence of adenomas did not differ from that observed in the fourth decade (8%) or seventh decade (10%).(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical study of granular cell tumors and granular pituicytes of the neurohypophysis

Six neurohypophysial GCTs and 31 normal neurohypophysis were studied by immunohistochemical techniques. The latter were grouped into A (< 5 yr old), B (30-49 yr), and C (> 70 yr). GCTs were all labeled by PNA, and some showed reactivity for S-100 protein, AAT, AAC, and cathepsin B. In addition, some were oxytocin- and vasopressinpositive. Unlike extracranial GCTs, neuron-specific enolase, myelin basic protein, and vimentin were not detected. Glial fibrillary acidic protein, keratin, and desmin were also not observed. In contrast, a few cells of the normal neurohypophysis showed immunoreactivity for AAT, AAC, cathepsin B, and PNA, similar to the cells of GCT. These cells tended to increase in number with age: group A showed fewer cathepsin B-positive cells than groups B and C (p < 0.001). These results show that neurohypophysial GCTs have some features that differentiate them from extracranial GCTs, for which a Schwann cell origin has been proposed by many authors. It was concluded that neurohypophysial GCT may originate from the cells that showed similar immunoreactivity, the "granular" pituicytes. Our results also support the hypothesis that neurohypophysial GCTs are an age-related metabolic disorder of lysosomes rather than true neoplasms.Endocr Pathol 4:140-145, 1993.