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Tarik Tihan - One of the best experts on this subject based on the ideXlab platform.
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Pituicytoma characterization of a unique neoplasm by histology immunohistochemistry ultrastructure and array based comparative genomic hybridization
Archives of Pathology & Laboratory Medicine, 2010Co-Authors: Joanna J Phillips, Sandeep Kunwar, Anjan Misra, Burt G Feuerstein, Tarik TihanAbstract:The Pituicytoma is a rare neoplasm whose histogenesis is debated partly because of the diversity of tissue types present in the sellar region. In this article we illustrate the characteristic histologic, immunohistologic, and ultrastructural features of this unique neoplasm. Furthermore, we use array-based comparative genomic hybridization to demonstrate a unique pattern of genomic copy number aberrations in Pituicytomas. Tumors were composed of bipolar, spindle cells that were immunopositive for S100, vimentin, and Bcl-2 and immunonegative for synaptophysin, chromogranin, and glial fibrillary acidic protein. Ultrastructural analysis was remarkable for absence of secretory granules. Array comparative genomic hybridization demonstrated genomic copy number imbalances, including losses on chromosome arms 1p, 14q, and 22q and gains on 5p. This pattern of genetic changes only partially overlaps with the genomic alterations reported in pituitary adenomas. In summary, our data suggest that Pituicytomas are a unique subset of tumors of the sellar region.
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Thyroid transcription factor 1 expression in sellar tumors: a histogenetic marker?
Journal of Neuropathology and Experimental Neurology, 2009Co-Authors: Tarik Tihan, Bernd W Scheithauer, Paul J. Zhang, Nicholas K. GonatasAbstract:Pituicytomas are rare low-grade gliomas of the neurohypophysis. Their morphology and variable immunophenotype have led to speculation that they arise from pituicytes. Given the role of thyroid transcription factor 1 (TTF-1) in the developing rodent infundibulum and its expression in the adult rat neurohypophysis, we speculated that TTF-1 would be a marker of human pituicytes. Using immunohistochemistry, we found that TTF-1 is strongly expressed in fetal and adult human pituicytes. A survey of sellar masses demonstrated specific TTF-1 expression in Pituicytomas (n = 3), atypical Pituicytomas (n = 2), and granular cell tumors (n = 4), indicating a common pituicyte lineage. TTF-1 expression in spindle cell oncocytomas (n = 8) is less easily explained but invites speculation. Our observations may have implications for the classification of these rare sellar neoplasms, all the while acknowledging the morphological diversity of pituicyte-related neoplasms.
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newly codified glial neoplasms of the 2007 who classification of tumours of the central nervous system angiocentric glioma pilomyxoid astrocytoma and Pituicytoma
Brain Pathology, 2007Co-Authors: Daniel J. Brat, Bernd W Scheithauer, Gregory N Fuller, Tarik TihanAbstract:th edition of the WHO Classification of Tumours of the Nervous System (WHO 2007) introduces changes that reflect both the recognition of new brain tumour types and a better understanding of neoplastic behavior. Three new tumours, angiocentric glioma (AG), pilomyxoid astrocytoma (PMA), and Pituicytoma are added to the section on gliomas. AG is a slowly growing cerebral tumour that typically presents with seizures in children and young adults. It is characterized by monomorphous, bipolar tumour cells with a striking perivascular growth pattern. Although the ‘cell of origin’ of AG is not clear, ultrastructural evidence points to an ependymal derivation. Typically, AG can be cured by total resection, and is designated WHO grade I. PMA is a solid, circumscribed tumour occurring mainly in the hypothalamic region of young children. It is composed of a monomorphous population of bipolar tumour cells within a rich myxoid background, with a conspicuous anglocentric arrangement. While PMA is considered a more aggressive variant of pilocytic astrocytoma, this relationship awaits further clarification. The PMA has been designated WHO grade II. The Pituicytoma, involves the posterior pituitary and/or its stalk and affects adults. It is solid in architecture, composed of spindle cells and presumably derived from pituicytes. Pituicytomas are indolent tumours, and are designated WHO grade I.
Bernd W Scheithauer - One of the best experts on this subject based on the ideXlab platform.
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Pituicytoma with gelsolin amyloid deposition
Endocrine Pathology, 2013Co-Authors: Mark E Jentoft, Bernd W Scheithauer, Jonathan M Morris, Ahmet Dogan, Joseph E Parisi, Kalman KovacsAbstract:Pituicytoma is a rare low-grade (WHO grade I) sellar region glioma. Among sellar tumors, pituitary adenomas, mainly prolactinomas, may show amyloid deposits. Gelsolin is a ubiquitous calcium-dependent protein that regulates actin filament dynamics. Two known gene point mutations result in gelsolin amyloid deposition, a characteristic feature of a rare type of familial amyloid polyneuropathy (FAP), the Finnish-type FAP, or hereditary gelsolin amyloidosis (HGA). HGA is an autosomal-dominant systemic amyloidosis, characterized by slowly progressive neurological deterioration with corneal lattice dystrophy, cranial neuropathy, and cutis laxa. A unique case of Pituicytoma with marked gelsolin amyloid deposition in a 67-year-old Chinese woman is described. MRI revealed a 2.6-cm well-circumscribed, uniformly contrast-enhancing solid sellar mass with suprasellar extension. Histologically, the lesion was characterized by solid sheets and fascicles of spindle cells with slightly fibrillary cytoplasm and oval nuclei with pinpoint nucleoli. Surrounding brain parenchyma showed marked reactive piloid gliosis. Remarkably, conspicuous amyloid deposits were identified as pink homogeneous spherules on light microscopy that showed apple-green birefringence on Congo red with polarization. Mass spectrometric-based proteomic analysis identified the amyloid as gelsolin type. Immunohistochemically, diffuse reactivity to S100 protein and TTF1, focal reactivity for GFAP, and no reactivity to EMA, synaptophysin, and chromogranin were observed. HGA-related mutations were not identified in the tumor. No recurrence was noted 14 months after surgery. To the knowledge of the authors, amyloid deposition in Pituicytoma or tumor-associated gelsolin amyloidosis has not been previously described. This novel finding expands the spectrum of sellar tumors that may be associated with amyloid deposition.
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Thyroid transcription factor 1 expression in sellar tumors: a histogenetic marker?
Journal of Neuropathology and Experimental Neurology, 2009Co-Authors: Tarik Tihan, Bernd W Scheithauer, Paul J. Zhang, Nicholas K. GonatasAbstract:Pituicytomas are rare low-grade gliomas of the neurohypophysis. Their morphology and variable immunophenotype have led to speculation that they arise from pituicytes. Given the role of thyroid transcription factor 1 (TTF-1) in the developing rodent infundibulum and its expression in the adult rat neurohypophysis, we speculated that TTF-1 would be a marker of human pituicytes. Using immunohistochemistry, we found that TTF-1 is strongly expressed in fetal and adult human pituicytes. A survey of sellar masses demonstrated specific TTF-1 expression in Pituicytomas (n = 3), atypical Pituicytomas (n = 2), and granular cell tumors (n = 4), indicating a common pituicyte lineage. TTF-1 expression in spindle cell oncocytomas (n = 8) is less easily explained but invites speculation. Our observations may have implications for the classification of these rare sellar neoplasms, all the while acknowledging the morphological diversity of pituicyte-related neoplasms.
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ependymoma of the sella turcica a variant of Pituicytoma
Human Pathology, 2009Co-Authors: Bernd W Scheithauer, Brooke Swearingen, Tessa Hedley E Whyte, Pavan K Auluck, Anat StemmerrachamimovAbstract:Summary A broad spectrum of neoplasms affects the sellar region. Among these, gliomas are rare, most being tumors of pituicytes such as granular cell tumor and Pituicytoma. Only 4 ependymomas of the human sellar region have been reported to date and all have had classic histologic features. Herein, we describe the clinicopathologic features of a sellar, low-grade ependymoma with unusual histology, but classic ultrastructural features, occurring in an elderly patient and thus expanding the spectrum of reported cases. The literature is reviewed and concepts of histogenesis are explored, particularly an origin in “ependymal pituicytes.” The concept that sellar ependymoma is pituicyte-derived is explored.
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newly codified glial neoplasms of the 2007 who classification of tumours of the central nervous system angiocentric glioma pilomyxoid astrocytoma and Pituicytoma
Brain Pathology, 2007Co-Authors: Daniel J. Brat, Bernd W Scheithauer, Gregory N Fuller, Tarik TihanAbstract:th edition of the WHO Classification of Tumours of the Nervous System (WHO 2007) introduces changes that reflect both the recognition of new brain tumour types and a better understanding of neoplastic behavior. Three new tumours, angiocentric glioma (AG), pilomyxoid astrocytoma (PMA), and Pituicytoma are added to the section on gliomas. AG is a slowly growing cerebral tumour that typically presents with seizures in children and young adults. It is characterized by monomorphous, bipolar tumour cells with a striking perivascular growth pattern. Although the ‘cell of origin’ of AG is not clear, ultrastructural evidence points to an ependymal derivation. Typically, AG can be cured by total resection, and is designated WHO grade I. PMA is a solid, circumscribed tumour occurring mainly in the hypothalamic region of young children. It is composed of a monomorphous population of bipolar tumour cells within a rich myxoid background, with a conspicuous anglocentric arrangement. While PMA is considered a more aggressive variant of pilocytic astrocytoma, this relationship awaits further clarification. The PMA has been designated WHO grade II. The Pituicytoma, involves the posterior pituitary and/or its stalk and affects adults. It is solid in architecture, composed of spindle cells and presumably derived from pituicytes. Pituicytomas are indolent tumours, and are designated WHO grade I.
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Pituicytoma a distinctive low grade glioma of the neurohypophysis
The American Journal of Surgical Pathology, 2000Co-Authors: Daniel J. Brat, Bernd W Scheithauer, Susan M Staugaitis, Robert N N Holtzman, Susan Morgello, Peter C BurgerAbstract:Pituicytoma is a rare, poorly characterized tumor of the sella and suprasellar region that is distinct morphologically from other local tumors and is thought to be derived from neurohypophyseal pituicytes. Clinical data, neuroimaging studies, and microsections were reviewed from nine such low-grade gliomas. Immunostains for glial, neuronal, and proliferation markers were performed on all nine tumors and six control neurohypophyses. Three tumors were studied ultrastructurally. Six men and three women, age 30 to 83 years (mean, 48 years), presented with visual symptoms, headache, or hypopituitarism. Magnetic resonance images showed solid, discrete, contrast-enhancing masses, four within the sella and five in the suprasellar space. The tumors consisted of sheets and/or fascicles of plump spindle cells with slightly fibrillar cytoplasm and slightly pleomorphic, oval-to-elongate nuclei with pinpoint nucleoli. Extracellular mucin was prominent in one tumor. Rosenthal fibers, granular bodies, and Herring bodies (granular axonal dilatations characteristic of the normal neurohypophysis) were lacking. Mitoses were rare or absent. MIB-1 labeling indices were low (0.5-2%). Tumor cells were strongly reactive for vimentin and S-100 protein, variably positive for glial fibrillary acidic protein, and nonreactive for synaptophysin and neurofilament protein. Cytoplasm varied in electron density and contained intermediate filaments. Neither meningothelial nor ependymal features were noted. Two tumors recurred at 20 and 26 months after subtotal resection, but none of the six completely resected tumors have done so. Pituicytomas are discrete, largely noninfiltrative low-grade gliomas of the sellar region that occur in adults. Their histologic appearance is distinct from pilocytic and ordinary, infiltrative astrocytomas. The distinction between Pituicytoma and normal neurohypophysis is aided by the latter's content of axons, Herring bodies, and perivascular anucleate zones rich in axonal terminations. Although curable by total excision, subtotal resection can be associated with recurrence.
Gianluigi Zona - One of the best experts on this subject based on the ideXlab platform.
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Pituitary image: Pituicytoma
Pituitary, 2015Co-Authors: Claudia Teti, Gianluigi Zona, Lara Castelletti, Luca Allegretti, Miryam Talco, Francesco Minuto, Mara Boschetti, Diego FeroneAbstract:Introduction Pituicytoma is a rare tumor arising from the neurohypophysis or pars intermedia of the adenohypophysis. Case report A 36 year old male came to our observation presenting polydipsia, polyuria, polyphagia, decreased libido and altered sleep-wake rhythm. The biochemical tests showed hypotonic urine, mild hyperprolactinemia, hypogonadotropic hypogonadism, central hypothyroidism. Magnetic resonance revealed an expansive lesion of the suprasellar region (slightly isointense on T1, hyperintense on T2, impregnating contrast medium), that was partially removed by trans-cranial neurosurgical approach. The histopathological diagnosis was Pituicytoma. After surgery, in addition to endocrine disorders, the patient presented severe neurological sequelae and hyperthermia, likely due to damage of the hypothalamus, followed by a progressive metabolic syndrome. The residual tumor was monitored by MRI, and, due to the early gradual increase in volume, was treated by stereotactic radiosurgery. Discussion/Conclusions Pituicytomas are often difficult to distinguish from other hypothalamic or pituitary lesions. However, their identification would be preferable in a pre-operative setting in order to optimize the work-up and to initiate a proactive management of the expected complications.
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pituitary image Pituicytoma
Pituitary, 2015Co-Authors: Claudia Teti, Gianluigi Zona, Lara Castelletti, Luca Allegretti, Miryam Talco, Francesco Minuto, Mara Boschetti, Diego FeroneAbstract:Introduction Pituicytoma is a rare tumor arising from the neurohypophysis or pars intermedia of the adenohypophysis.
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Pituicytomas: radiological findings, clinical behavior and surgical management
Acta Neurochirurgica, 2012Co-Authors: Francesca Secci, Paolo Merciadri, Diego Criminelli Rossi, Alessandro D’andrea, Gianluigi ZonaAbstract:Background Pituicytomas are rare low-grade glial neoplasms originating in the neurohypophysis or infundibulum that appear as solid, noninfiltrative masses occupying the sella turcica, the suprasellar space or both. Due to their high tendency to bleed and the possible firmness and adhesion to surrounding structures, preoperative diagnosis of Pituicytoma is a goal for the surgeon, but it is actually a challenge because of the absence of distinctive clinical or neuroradiological findings. Methods We report the new cases of three patients who underwent transsphenoidal surgery for suspected pituitary adenomas, which were determined to be Pituicytomas at histological and immunohistochemical analysis. We also review previously reported cases of Pituicytoma in the literature. Results To date, 51 cases of Pituicytoma have been reported in addition to our own cases. The natural history and clinical characteristics of this rare tumor are outlined. Conclusions Macroscopic aspects are variable, and final diagnosis is made from the typical histological and immunohistochemical pattern. The therapy of choice is gross total surgical resection since subtotal removal can lead to local regrowth, but the time to recurrence is unpredictable and highly variable. The role of adjuvant therapy is currently undefined.
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Pituicytomas: radiological findings, clinical behavior and surgical management.
Acta Neurochirurgica, 2011Co-Authors: Francesca Secci, Paolo Merciadri, Diego Criminelli Rossi, Alessandro D'andrea, Gianluigi ZonaAbstract:Background Pituicytomas are rare low-grade glial neoplasms originating in the neurohypophysis or infundibulum that appear as solid, noninfiltrative masses occupying the sella turcica, the suprasellar space or both. Due to their high tendency to bleed and the possible firmness and adhesion to surrounding structures, preoperative diagnosis of Pituicytoma is a goal for the surgeon, but it is actually a challenge because of the absence of distinctive clinical or neuroradiological findings.
Carles Villabona - One of the best experts on this subject based on the ideXlab platform.
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Primary tumors of the posterior pituitary: A systematic review
Reviews in Endocrine and Metabolic Disorders, 2019Co-Authors: Fernando Guerrero-pérez, Agustina Pia Marengo, Noemi Vidal, Pedro Iglesias, Carles VillabonaAbstract:In 2017, the World Health Organization established that Pituicytoma, granular cell tumor (GCT), spindle cell oncocytoma (SCO) and sellar ependymomas (SE) are posterior pituitary tumors (PPT). They probably arise from the pituicytes and may constitute a unique histopathological entity. We carried out a systematic review using PubMed’s database. A total of 266 patients with pathological diagnosis of PPT (135 Pituicytomas, 69 GCT, 47 SCO, 8 SE and 7 mixed histology tumors) were analyzed. Gender distribution was identical and median age at diagnosis was 48 ± 21.8 years. Main presentation symptoms were visual disorders ( n = 142; 58.1%), headache ( n = 99; 40.5%), hypopituitarism ( n = 84; 34.4%), hypercortisolism ( n = 10; 4.1%), polyuriapolydipsia ( n = 6; 2.4%) and acromegaly features ( n = 5; 2.0%). On MRI, 122 (47.6%) patients showed sellar with suprasellar extension masses, 67 (23.1%) were suprasellar and 63 (24.6%) exclusively sellar. Median tumor size was 22.0 ± 14.2 mm. Two hundred sixty four patients underwent surgery, transphenoidal access was selected in 132 (64.4%) and craniotomy in 58 (28.3%). Complications were hypopituitarism ( n = 70; 42.1%), diabetes insipidus ( n = 55; 33.1%) and hemorrhage ( n = 50; 30.1%). Tumor persisted in 93 patients (45.6%) and recurred in 13 (6.4%). Regarding comparison between main types of PPT, SCO patients were diagnosed later (60.0 vs 47.0 vs 47.0 years, p = 0.023), the tumor was larger 25.0 mm [10.8] vs 20.0 mm [14.2] vs 2.0 mm [15.0] and they were frequently sellar with suprasellar extension tumors (71.7% vs 46.2% vs 32.8%, p = 0.003) compared to Pituicytoma and GCT. In conclusion, PPT are rare tumors and have been misdiagnosed mainly as non-functioning pituitary adenomas. Different types of PPT share similar epidemiology, clinical manifestations and surgical outcomes. Surgery is the only curative option but complications and subtotal resection are common.
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Posterior pituitary tumours: the spectrum of a unique entity. A clinical and histological study of a large case series
Endocrine, 2019Co-Authors: Fernando Guerrero-pérez, Agustina Pia Marengo, Noemi Vidal, Pedro Iglesias, Carlos Del Pozo, Concepción Blanco, David Rivero-celada, Juan J. Díez, Antonio Picó, Carles VillabonaAbstract:Purpose In 2017, the WHO established that Pituicytoma, granular cell tumour (GCT) and spindle cell oncocytoma (SCO) are posterior pituitary tumours (PPT). Recent data suggests that these tumours probably arise from the pituicytes and may constitute a spectrum of a unique histopathological entity. Our aim is to report the clinical findings and surgical outcomes of 16 patients with PPT. We also evaluated the tissue specimens available in light of current knowledge. Method Cross-sectional study with retrospective data. Results PPT were 7 Pituicytomas, 3 GCT and 6 SCO. Patients mean age was 55 years old and 75% were female. Basal hormonal study showed hyperprolactinemia (43.7%) and hypopituitarism (37.5%). There was no case of diabetes insipidus (DI). MRI showed sellar/suprasellar masses with mean size of 19.7mm. PPT was not suspected in any patient. Fifteen patients underwent surgery and complications were common: 20% had perioperative bleeding (one patient died because of a massive haemorrhage), 57.1% hypopituitarism, 35.7% permanent DI and 21.4% underwent a second surgery. Pathological findings shown positivity for thyroid transcription factor 1, vimentin and negativity for cytokeratin and chromogranin A in all specimens evaluated. S100 protein was positive in 88.8% of tumours. Ki67 was ≥ 3% in 66.6% and ranged from 4-7% in SCO. Conclusion PPT have similar histology, clinical features and are frequently misdiagnosed as nonfunctioning pituitary tumours. However, post-surgical complications including haemorrhage are common. A high clinical suspicion is needed to presume the diagnosis prior surgery and diminish the high morbidity of these tumours.
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Posterior pituitary tumours: the spectrum of a unique entity. A clinical and histological study of a large case series.
Endocrine, 2018Co-Authors: Fernando Guerrero-pérez, Agustina Pia Marengo, Noemi Vidal, Pedro Iglesias, Carlos Del Pozo, Concepción Blanco, David Rivero-celada, Juan J. Díez, Antonio Picó, Carles VillabonaAbstract:In 2017, the WHO established that Pituicytoma, granular cell tumour (GCT) and spindle cell oncocytoma (SCO) are posterior pituitary tumours (PPT). Recent data suggests that these tumours probably arise from the pituicytes and may constitute a spectrum of a unique histopathological entity. Our aim is to report the clinical findings and surgical outcomes of 16 patients with PPT. We also evaluated the tissue specimens available in light of current knowledge. Cross-sectional study with retrospective data. PPT were 7 Pituicytomas, 3 GCT and 6 SCO. Patients mean age was 55 years old and 75% were female. Basal hormonal study showed hyperprolactinemia (43.7%) and hypopituitarism (37.5%). There was no case of diabetes insipidus (DI). MRI showed sellar/suprasellar masses with mean size of 19.7mm. PPT was not suspected in any patient. Fifteen patients underwent surgery and complications were common: 20% had perioperative bleeding (one patient died because of a massive haemorrhage), 57.1% hypopituitarism, 35.7% permanent DI and 21.4% underwent a second surgery. Pathological findings shown positivity for thyroid transcription factor 1, vimentin and negativity for cytokeratin and chromogranin A in all specimens evaluated. S100 protein was positive in 88.8% of tumours. Ki67 was ≥ 3% in 66.6% and ranged from 4-7% in SCO. PPT have similar histology, clinical features and are frequently misdiagnosed as nonfunctioning pituitary tumours. However, post-surgical complications including haemorrhage are common. A high clinical suspicion is needed to presume the diagnosis prior surgery and diminish the high morbidity of these tumours.
Manish K. Aghi - One of the best experts on this subject based on the ideXlab platform.
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Pituicytomas and spindle cell oncocytomas: modern case series from the University of California, San Francisco
Pituitary, 2015Co-Authors: Corinna C. Zygourakis, John D. Rolston, Carlene Partow, Sandeep Kunwar, Manish K. AghiAbstract:Purpose Pituicytomas and spindle cell oncocytomas (SCOs) are extremely rare neoplasms of the sellar and suprasellar region that can often mimic pituitary adenomas. To date, there are relatively few cases of Pituicytomas and SCOs reported; and most of these are small case series. Methods In this paper, we provide a retrospective review of the treatment, imaging characteristics, post-operative course, and histopathology of five cases of Pituicytomas and two SCOs treated at the University of California, San Francisco (UCSF) over a 10-year period from 2003 to 2013. Results We find that Pituicytomas and SCOs present similarly to pituitary adenomas, and look identical on CT or MR imaging. We histopathologically confirmed all Pituicytomas with a combination of hematoxylin and eosin morphology and immunohistochemical positivity for vimentin and S100; SCOs stain for anti-mitochondrial antigen and endothelial membrane antigen. We observe positive thyroid transcription factor 1 (TTF1) immunohistochemistry in both cases of SCO, as well as in both of the cases of Pituicytoma in which TTF1 staining was available. Conclusions This represents the largest single-institution case series of Pituicytomas and SCOs to date, and also includes the first description of the management of a pregnant female with SCO. Our findings are consistent with the idea of common histogenesis for Pituicytomas and SCOs, and also raise the possibility of more aggressive growth in SCOs as compared to Pituicytomas.
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Pituicytomas and spindle cell oncocytomas: modern case series from the University of California, San Francisco
Pituitary, 2014Co-Authors: Corinna C. Zygourakis, John D. Rolston, Carlene Partow, Sandeep Kunwar, Manish K. AghiAbstract:Purpose Pituicytomas and spindle cell oncocytomas (SCOs) are extremely rare neoplasms of the sellar and suprasellar region that can often mimic pituitary adenomas. To date, there are relatively few cases of Pituicytomas and SCOs reported; and most of these are small case series.