TL;DR: A new terminology, pituitary neuroendocrine tumor (PitNET), is proposed, which is consistent with that used for other neuro endocrine neoplasms and which recognizes the highly variable impact of these tumors on patients.
Abstract: The classification of neoplasms of adenohypophysial cells is misleading because of the simplistic distinction between adenoma and carcinoma, based solely on metastatic spread and the poor reproducibility and predictive value of the definition of atypical adenomas based on the detection of mitoses or expression of Ki-67 or p53. In addition, the current classification of neoplasms of the anterior pituitary does not accurately reflect the clinical spectrum of behavior. Invasion and regrowth of proliferative lesions and persistence of hormone hypersecretion cause significant morbidity and mortality. We propose a new terminology, pituitary neuroendocrine tumor (PitNET), which is consistent with that used for other neuroendocrine neoplasms and which recognizes the highly variable impact of these tumors on patients.
TL;DR: This work believes this conceptual approach can form the basis for the next generation of NEN classifications and will allow more consistent taxonomy to understand how neoplasms from different organ systems inter-relate clinically and genetically.
688 citations
Cites background or result from "From pituitary adenoma to pituitary..."
...PitNET prognosis and prediction relies more on cell type and degree of cell differentiation than on proliferative markers [10]....
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...It was noted that the recently proposed new terminology for pituitary tumors is more in line with this proposal than the current 2017 WHO terminology [10]....
TL;DR: This review focuses on discussing the main changes on the upcoming fourth edition of the WHO Classification of Tumors of the Pituitary Gland emphasizing histopathological and molecular genetics aspects of pituitary neuroendocrine tumor aspects and some of the non-neuroendocrine tumors involving the pituitsary gland.
Abstract: This review focuses on discussing the main changes on the upcoming fourth edition of the WHO Classification of Tumors of the Pituitary Gland emphasizing histopathological and molecular genetics aspects of pituitary neuroendocrine (i.e., pituitary adenomas) and some of the non-neuroendocrine tumors involving the pituitary gland. Instead of a formal review, we introduced the highlights of the new WHO classification by answering select questions relevant to practising pathologists. The revised classification of pituitary adenomas, in addition to hormone immunohistochemistry, recognizes the role of other immunohistochemical markers including but not limited to pituitary transcription factors. Recognizing this novel approach, the fourth edition of the WHO classification has abandoned the concept of “a hormone-producing pituitary adenoma” and adopted a pituitary adenohypophyseal cell lineage designation of the adenomas with subsequent categorization of histological variants according to hormone content and specific histological and immunohistochemical features. This new classification does not require a routine ultrastructural examination of these tumors. The new definition of the Null cell adenoma requires the demonstration of immunonegativity for pituitary transcription factors and adenohypophyseal hormones Moreover, the term of atypical pituitary adenoma is no longer recommended. In addition to the accurate tumor subtyping, assessment of the tumor proliferative potential by mitotic count and Ki-67 index, and other clinical parameters such as tumor invasion, is strongly recommended in individual cases for consideration of clinically aggressive adenomas. This classification also recognizes some subtypes of pituitary neuroendocrine tumors as “high-risk pituitary adenomas” due to the clinical aggressive behavior; these include the sparsely granulated somatotroph adenoma, the lactotroph adenoma in men, the Crooke’s cell adenoma, the silent corticotroph adenoma, and the newly introduced plurihormonal Pit-1-positive adenoma (previously known as silent subtype III pituitary adenoma). An additional novel aspect of the new WHO classification was also the definition of the spectrum of thyroid transcription factor-1 expressing pituitary tumors of the posterior lobe as representing a morphological spectrum of a single nosological entity. These tumors include the pituicytoma, the spindle cell oncocytoma, the granular cell tumor of the neurohypophysis, and the sellar ependymoma.
283 citations
Cites methods from "From pituitary adenoma to pituitary..."
...Subsequent to the WHO endocrine bluebook preparation, a group of experts and attendees of the 14th meeting of the International Pituitary Pathology Club (November 2016, France) have challenged the concept of pituitary adenomas by proposing the term Bpituitary neuroendocrine tumor (PitNET)^ in order reflect better the biological aggressiveness of some of the non-metastatic pituitary adenomas as well as the lack of reliable morphological criteria in the distinction of tumors that will present later on with metastatic disease [35]....
TL;DR: A comprehensive pangenomic classification of PitNETs is reported, which improves the understanding and affects the clinical stratification of patients with Pit NETs.
TL;DR: A concise review of the clinical and pathological aspects of silent pituitary adenomas was conducted in view of the new World Health Organization classification of pituitaries, which needs to be evaluated to better serve this unique group of patients.
Abstract: Context Silent pituitary adenomas are anterior pituitary tumors with hormone synthesis but without signs or symptoms of hormone hypersecretion. They have been increasingly recognized and represent challenging diagnostic issues. Evidence acquisition A comprehensive literature search was performed using MEDLINE and EMBASE databases from January 2000 to March 2018 with the following key words: (i) pituitary adenoma/tumor and nonfunctioning; or (ii) pituitary adenoma/tumor and silent. All titles and abstracts of the retrieved articles were reviewed, and recent advances in the field of silent pituitary adenomas were summarized. Evidence synthesis The clinical and biochemical picture of pituitary adenomas reflects a continuum between functional and silent adenomas. Although some adenomas are truly silent, others will show some evidence of biochemical hypersecretion or could have subtle clinical signs and, therefore, can be referred to as clinically silent or "whispering" adenomas. Silent tumors seem to be more aggressive than their secreting counterparts, with a greater recurrence rate. Transcription factors for pituitary cell lineages have been introduced into the 2017 World Health Organization guidelines: steroidogenic factor 1 staining for gonadotroph lineage; PIT1 (pituitary-specific positive transcription factor 1) for growth hormone, prolactin, and TSH lineage, and TPIT for the corticotroph lineage. Prospective studies applying these criteria will establish the value of the new classification. Conclusions A concise review of the clinical and pathological aspects of silent pituitary adenomas was conducted in view of the new World Health Organization classification of pituitary adenomas. New classifications, novel prognostics markers, and emerging imaging and therapeutic approaches need to be evaluated to better serve this unique group of patients.
TL;DR: The term “metastatic PitNET” is advocated to replace the previous terminology “pituitary carcinoma” in order to avoid confusion with neuro endocrine carcinoma (a poorly differentiated epithelial neuroendocrine neoplasm).
TL;DR: Pathology and Genetics of Tumours of Endocrine OrgansMolecular Pathology of Breast CancerWho Classification of TUMoursPathology & Genetics of Surgical Tissues, Haematopoietic and Lymphoid Tissues and Soft Tissue Pathology.
Abstract: Pathology and Genetics of Tumours of Endocrine OrgansMolecular Pathology of Breast CancerWho Classification of Tumours of the Lung, Pleura, Thymus and HeartPathology and Genetics of Tumours of the Nervous SystemWHO Classification of Skin TumoursThe Molecular Basis of CancerMolecular Genetics of Lung CancerPathology and Genetics of Tumours of the Digestive SystemPathology and Genetics of Tumours of Head and Neck TumoursFemale Genital Tumours: Who Classification of TumoursPathology & Genetics of Tumours of Haematopoietic and Lymphoid TissuesModern Soft Tissue PathologyPathology and Genetics of Tumours of Endocrine OrgansWHO Classification of Tumours of the Digestive SystemPathology and Genetics of Tumours of the SkinWHO Classification of Tumours of the Urinary System and Male Genital OrgansWHO Classification of Tumours of the Central Nervous SystemPathology and Genetics of Tumours of the Breast and Female Genital OrgansWHO Classification of Tumours of Haematopoietic and Lymphoid TissuesWHO Classification of Tumours of Female Reproductive OrgansWHO Classification of Head and Neck TumoursPathology and Genetics of Tumours of the Nervous SystemPathology and Genetics of Tumours of Haematopoietic and Lymphoid TissuesPathology and Genetics of Tumours of the Nervous SystemWHO Classification of Tumours of Soft Tissue and BonePathology and Genetics of Tumours of the Urinary System and Male Genital OrgansSoft Tissue
1,622 citations
"From pituitary adenoma to pituitary..." refers background or methods in this paper
...2004) and will remain in the next WHO classification that is underway....
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...Although the new terminology of ‘tumor’ replacing ‘adenoma’ will not be incorporated in the 2017 WHO book, this change, as with previous terminologies that transitioned to ‘NETs’, will be gradually adopted to be included in the next edition....
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...The classification by morphologic cell type has been adopted by the World Health Organization (WHO) (DeLellis et al....
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...Traditional classifications only recognize malignancy, denoted as pituitary carcinoma, when there is evidence of distant metastasis or cerebrospinal spread (DeLellis et al. 2004)....
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...The classification by morphologic cell type has been adopted by the World Health Organization (WHO) (DeLellis et al. 2004) and will remain in the next WHO classification that is underway....
TL;DR: A new, easy to use clinicopathological classification of pituitary endocrine tumours has demonstrated its prognostic worth by strongly predicting the probability of post-operative complete remission or tumour progression and so could help clinicians choose the best post-operation therapy.
Abstract: Pituitary adenomas are currently classified by histological, immunocytochemical and numerous ultrastructural characteristics lacking unequivocal prognostic correlations. We investigated the prognostic value of a new clinicopathological classification with grades based on invasion and proliferation. This retrospective multicentric case-control study comprised 410 patients who had surgery for a pituitary tumour with long-term follow-up. Using pituitary magnetic resonance imaging for diagnosis of cavernous or sphenoid sinus invasion, immunocytochemistry, markers of the cell cycle (Ki-67, mitoses) and p53, tumours were classified according to size (micro, macro and giant), type (PRL, GH, FSH/LH, ACTH and TSH) and grade (grade 1a: non-invasive, 1b: non-invasive and proliferative, 2a: invasive, 2b: invasive and proliferative, and 3: metastatic). The association between patient status at 8-year follow-up and age, sex, and classification was evaluated by two multivariate analyses assessing disease- or recurrence/progression-free status. At 8 years after surgery, 195 patients were disease-free (controls) and 215 patients were not (cases). In 125 of the cases the tumours had recurred or progressed. Analyses of disease-free and recurrence/progression-free status revealed the significant prognostic value (p < 0.001; p < 0.05) of age, tumour type, and grade across all tumour types and for each tumour type. Invasive and proliferative tumours (grade 2b) had a poor prognosis with an increased probability of tumour persistence or progression of 25- or 12-fold, respectively, as compared to non-invasive tumours (grade 1a). This new, easy to use clinicopathological classification of pituitary endocrine tumours has demonstrated its prognostic worth by strongly predicting the probability of post-operative complete remission or tumour progression and so could help clinicians choose the best post-operative therapy.
TL;DR: Anterior pituitsary tumors are clonal proliferation of pituitary cells that usually consist of one cell type, although some adenomas consist of more than one celltype.
Abstract: Anterior pituitary tumors are clonal proliferation of pituitary cells. They usually consist of one cell type, although some adenomas consist of more than one cell type.