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Endocrine Pathology Mar 2022This review summarizes the changes in the 5th Edition of the WHO Classification of Endocrine and Neuroendocrine Tumors that relate to the pituitary gland. The new... (Review)
Review
This review summarizes the changes in the 5th Edition of the WHO Classification of Endocrine and Neuroendocrine Tumors that relate to the pituitary gland. The new classification clearly distinguishes anterior lobe (adenohypophyseal) from posterior lobe (neurohypophyseal) and hypothalamic tumors. Other tumors arising in the sellar region are also discussed. Anterior lobe tumors include (i) well-differentiated adenohypophyseal tumors that are now classified as pituitary neuroendocrine tumors (PitNETs; formerly known as pituitary adenomas), (ii) pituitary blastoma, and (iii) the two types of craniopharyngioma. The new WHO classification provides detailed histological subtyping of a PitNET based on the tumor cell lineage, cell type, and related characteristics. The routine use of immunohistochemistry for pituitary transcription factors (PIT1, TPIT, SF1, GATA3, and ERα) is endorsed in this classification. The major PIT1, TPIT, and SF1 lineage-defined PitNET types and subtypes feature distinct morphologic, molecular, and clinical differences. The "null cell" tumor, which is a diagnosis of exclusion, is reserved for PitNETs with no evidence of adenohypophyseal lineage differentiation. Unlike the 2017 WHO classification, mammosomatotroph and acidophil stem cell tumors represent distinct PIT1-lineage PitNETs. The diagnostic category of PIT1-positive plurihormonal tumor that was introduced in the 2017 WHO classification is replaced by two clinicopathologically distinct PitNETs: the immature PIT1-lineage tumor (formerly known as silent subtype 3 tumor) and the mature plurihormonal PIT1-lineage tumor. Rare unusual plurihormonal tumors feature multi-lineage differentiation. The importance of recognizing multiple synchronous PitNETs is emphasized to avoid misclassification. The term "metastatic PitNET" is advocated to replace the previous terminology "pituitary carcinoma" in order to avoid confusion with neuroendocrine carcinoma (a poorly differentiated epithelial neuroendocrine neoplasm). Subtypes of PitNETs that are associated with a high risk of adverse biology are emphasized within their cell lineage and cell type as well as based on clinical variables. Posterior lobe tumors, the family of pituicyte tumors, include the traditional pituicytoma, the oncocytic form (spindle cell oncocytoma), the granular cell form (granular cell tumor), and the ependymal type (sellar ependymoma). Although these historical terms are entrenched in the literature, they are nonspecific and confusing, such that oncocytic pituicytoma, granular cell pituicytoma, and ependymal pituicytoma are now proposed as more accurate. Tumors with hypothalamic neuronal differentiation are classified as gangliocytomas or neurocytomas based on large and small cell size, respectively. This classification sets the standard for a high degree of sophistication to allow individualized patient management approaches.
Topics: Adenoma; Craniopharyngioma; Humans; Pituitary Gland; Pituitary Neoplasms; World Health Organization
PubMed: 35291028
DOI: 10.1007/s12022-022-09703-7 -
Endocrinology and Metabolism Clinics of... Sep 2020Pituitary adenomas are usually nonmalignant, but have a heavy burden on patients and health care systems. Increased availability of MRI has led to an increase in... (Review)
Review
Pituitary adenomas are usually nonmalignant, but have a heavy burden on patients and health care systems. Increased availability of MRI has led to an increase in incidentally found pituitary lesions and clinically relevant pituitary adenomas. Epidemiologic studies show that pituitary adenomas are increasing in incidence (between 3.9 and 7.4 cases per 100,000 per year) and prevalence (76 to 116 cases per 100,000 population) in the general population (approximately 1 case per 1000 of the general population). Most new cases diagnosed are prolactinomas and nonsecreting pituitary adenomas. Most clinically relevant pituitary adenomas occur in females, but pituitary adenomas are clinically heterogeneous.
Topics: Adenoma; Humans; Incidence; Pituitary Neoplasms; Prevalence
PubMed: 32741475
DOI: 10.1016/j.ecl.2020.04.002 -
The Journal of Clinical Endocrinology... Aug 2023Prolactinomas are the most common pituitary tumor histotype, with microprolactinomas being prevalent in women and macroprolactinomas in men. Hyperprolactinemia is among... (Review)
Review
Prolactinomas are the most common pituitary tumor histotype, with microprolactinomas being prevalent in women and macroprolactinomas in men. Hyperprolactinemia is among the most common causes of hypogonadotropic hypogonadism in both sexes, prompting medical advice for hypogonadism (infertility, oligo-amenorrhea, impotence, osteoporosis/osteopenia) in both sexes, and for signs and symptoms of mass effects (hypopituitarism, visual loss, optic chiasm compression, cranial nerve deficits, headaches) predominantly in men. Diagnostic workup involves a single prolactin measurement and pituitary imaging, but some laboratory artifacts (ie, the "hook effect" and macroprolactin) can complicate or delay the diagnosis. The treatment of choice for prolactinomas is represented by dopamine agonists, mainly cabergoline, which are able to induce disease control, restore fertility in both sexes, and definitively cure one-third of patients, thus permitting treatment discontinuation. Pregnancy and menopause may promote spontaneous prolactin decline and anticipate cabergoline discontinuation in women. Surgery and/or radiotherapy are indicated in case of resistance to cabergoline not overcome by the increase in drug dose up to the maximally tolerated or the patient's personal choice of surgery. The evidence of resistance to cabergoline in invasive and proliferative tumors may indicate biological aggressiveness, thus requiring alternative therapeutic approaches mainly based on temozolomide use as monotherapy or combined with radiotherapy. In uncontrolled patients, new medical approaches (alternative hormonal treatments, cytotoxic drugs, peptide receptor radionuclide therapy, mTOR/Akt inhibitors, tyrosine kinase inhibitors, or immunotherapy) may be offered but the experience collected to date is still very scant. This article reviews different facets of prolactinomas and discusses approaches to the condition in more common clinical situations.
Topics: Male; Pregnancy; Humans; Female; Prolactinoma; Cabergoline; Prolactin; Ergolines; Pituitary Neoplasms; Dopamine Agonists; Hypogonadism
PubMed: 36974474
DOI: 10.1210/clinem/dgad174 -
Ugeskrift For Laeger May 2019In this review, we discuss pituitary adenomas (PA), which account for 10-25% of the intracranial tumours. Despite their benign nature, PA often show invasive growth.... (Review)
Review
In this review, we discuss pituitary adenomas (PA), which account for 10-25% of the intracranial tumours. Despite their benign nature, PA often show invasive growth. Pressure on neighbouring structures may cause hypopituitarism or vision field impairment. For PA, except prolactinomas, surgical treatment is first choice. The primary surgical technique is transsphenoidal surgery. Pituitary function, vision and post-operative magnetic resonance imaging scan is evaluated in a multidisciplinary team of neurosurgeons and endocrinologist 6-8 weeks post-operatively. Follow-up and treatment of pituitary adenomas is highly specialised and requires a team of dedicated endocrinologists and neurosurgeons.
Topics: Adenoma; Humans; Magnetic Resonance Imaging; Pituitary Neoplasms; Treatment Outcome
PubMed: 31124446
DOI: No ID Found -
Nature Reviews. Endocrinology Nov 2021Although usually benign, anterior pituitary tumours occasionally exhibit aggressive behaviour, with invasion of surrounding tissues, rapid growth, resistance to... (Review)
Review
Although usually benign, anterior pituitary tumours occasionally exhibit aggressive behaviour, with invasion of surrounding tissues, rapid growth, resistance to conventional treatments and multiple recurrences. In very rare cases, they metastasize and are termed pituitary carcinomas. The time between a 'classical' pituitary tumour and a pituitary carcinoma can be years, which means that monitoring should be performed regularly in patients with clinical (invasion and/or tumour growth) or pathological (Ki67 index, mitotic count and/or p53 detection) markers suggesting aggressiveness. However, although both invasion and proliferation have prognostic value, such parameters cannot predict outcome or malignancy without metastasis. Future research should focus on the biology of both tumour cells and their microenvironment, hopefully with improved therapeutic outcomes. Currently, the initial therapeutic approach for aggressive pituitary tumours is generally to repeat surgery or radiotherapy in expert centres. Standard medical treatments usually have no effect on tumour progression but they can be maintained on a long-term basis to, at least partly, control hypersecretion. In cases where standard treatments prove ineffective, temozolomide, the sole formally recommended treatment, is effective in only one-third of patients. Personalized use of emerging therapies, including peptide receptor radionuclide therapy, angiogenesis-targeted therapy and immunotherapy, will hopefully improve the outcomes of patients with this severe condition.
Topics: Craniopharyngioma; Humans; Immunotherapy; Pituitary Neoplasms; Temozolomide; Tumor Microenvironment
PubMed: 34493834
DOI: 10.1038/s41574-021-00550-w -
JAMA Feb 2017Pituitary adenomas may hypersecrete hormones or cause mass effects. Therefore, early diagnosis and treatment are important. (Review)
Review
IMPORTANCE
Pituitary adenomas may hypersecrete hormones or cause mass effects. Therefore, early diagnosis and treatment are important.
OBSERVATIONS
Prevalence of pituitary adenomas ranges from 1 in 865 adults to 1 in 2688 adults. Approximately 50% are microadenomas (<10 mm); the remainder are macroadenomas (≥10 mm). Mass effects cause headache, hypopituitarism, and visual field defects. Treatments include transsphenoidal surgery, medical therapies, and radiotherapy. Prolactinomas account for 32% to 66% of adenomas and present with amenorrhea, loss of libido, galactorrhea, and infertility in women and loss of libido, erectile dysfunction, and infertility in men; they are generally treated with the dopamine agonists cabergoline and bromocriptine. Growth hormone-secreting tumors account for 8% to 16% of tumors and usually present with enlargement of the lips, tongue, nose, hands, and feet and are diagnosed by elevated insulin-like growth factor 1 levels and growth hormone levels; initial treatment is surgical. Medical therapy with somatostatin analogues, cabergoline, and pegvisomant is often also needed. Adrenocorticotropic hormone (ACTH)-secreting tumors account for 2% to 6% of adenomas and are associated with obesity, hypertension, diabetes, and other morbidity. Measurement of a late-night salivary cortisol level is the best screening test but petrosal sinus sampling for ACTH may be necessary to distinguish a pituitary from an ectopic source. The primary treatment of Cushing disease (hypercortisolism due to ACTH-producing adenomas, which is the cause in approximately 65% of the cases of hypercortisolism) is adenoma resection and medical therapies including ketoconazole, mifepristone, and pasireotide. Hyperthyroidism due to thyroid-stimulating hormone-secreting tumors accounts for 1% of tumors and is treated with surgery and somatostatin analogues if not surgically cured. Clinically nonfunctioning adenomas account for 15% to 54% of adenomas and present with mass effects; surgery is generally required, although incidentally found tumors can be followed if they are asymptomatic.
CONCLUSIONS AND RELEVANCE
Patients with pituitary adenomas should be identified at an early stage so that effective treatment can be implemented. For prolactinomas, initial therapy is generally dopamine agonists. For all other pituitary adenomas, initial therapy is generally transsphenoidal surgery with medical therapy being reserved for those not cured by surgery.
Topics: Adenoma; Female; Hormone Antagonists; Humans; Male; Pituitary ACTH Hypersecretion; Pituitary Neoplasms; Prolactinoma
PubMed: 28170483
DOI: 10.1001/jama.2016.19699 -
Head and Neck Pathology Mar 2022This review article provides a brief overview of the new WHO classification by adopting a question-answer model to highlight the spectrum of head and neck neuroendocrine... (Review)
Review
Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Overview of the 2022 WHO Classification of Head and Neck Neuroendocrine Neoplasms.
This review article provides a brief overview of the new WHO classification by adopting a question-answer model to highlight the spectrum of head and neck neuroendocrine neoplasms which includes epithelial neuroendocrine neoplasms (neuroendocrine tumors and neuroendocrine carcinomas) arising from upper aerodigestive tract and salivary glands, and special neuroendocrine neoplasms including middle ear neuroendocrine tumors (MeNET), ectopic or invasive pituitary neuroendocrine tumors (PitNET; formerly known as pituitary adenoma) and Merkel cell carcinoma as well as non-epithelial neuroendocrine neoplasms (paragangliomas). The new WHO classification follows the IARC/WHO nomenclature framework and restricts the diagnostic term of neuroendocrine carcinoma to poorly differentiated epithelial neuroendocrine neoplasms. In this classification, well-differentiated epithelial neuroendocrine neoplasms are termed as neuroendocrine tumors (NET), and are graded as G1 NET (no necrosis and < 2 mitoses per 2 mm; Ki67 < 20%), G2 NET (necrosis or 2-10 mitoses per 2 mm, and Ki67 < 20%) and G3 NET (> 10 mitoses per 2 mm or Ki67 > 20%, and absence of poorly differentiated cytomorphology). Neuroendocrine carcinomas (> 10 mitoses per 2 mm, Ki67 > 20%, and often associated with a Ki67 > 55%) are further subtyped based on cytomorphological characteristics as small cell and large cell neuroendocrine carcinomas. Unlike neuroendocrine carcinomas, head and neck NETs typically show no aberrant p53 expression or loss of RB reactivity. Ectopic or invasive PitNETs are subtyped using pituitary transcription factors (PIT1, TPIT, SF1, GATA3, ER-alpha), hormones and keratins (e.g., CAM5.2). The new classification emphasizes a strict correlation of morphology and immunohistochemical findings in the accurate diagnosis of neuroendocrine neoplasms. A particular emphasis on the role of biomarkers in the confirmation of the neuroendocrine nature of a neoplasm and in the distinction of various neuroendocrine neoplasms is provided by reviewing ancillary tools that are available to pathologists in the diagnostic workup of head and neck neuroendocrine neoplasms. Furthermore, the role of molecular immunohistochemistry in the diagnostic workup of head and neck paragangliomas is discussed. The unmet needs in the field of head and neck neuroendocrine neoplasms are also discussed in this article. The new WHO classification is an important step forward to ensure accurate diagnosis that will also form the basis of ongoing research in this field.
Topics: Carcinoma, Neuroendocrine; Head and Neck Neoplasms; Humans; Ki-67 Antigen; Neuroendocrine Tumors; Paraganglioma; Pituitary Neoplasms; World Health Organization
PubMed: 35312985
DOI: 10.1007/s12105-022-01435-8 -
Veterinary Journal (London, England :... Apr 2021Pituitary tumours are common in dogs and are being increasingly recognized in cats. Pituitary tumours are usually classified as adenomas and should only be classified as... (Review)
Review
Pituitary tumours are common in dogs and are being increasingly recognized in cats. Pituitary tumours are usually classified as adenomas and should only be classified as carcinomas when there is evidence of metastatic spread of the tumour, which is rare. Despite the benign nature of most pituitary tumours, they can still compress or invade neighbouring tissues. Pituitary tumours can be functional (hormonally active) or non-functional (hormonally silent). The aim of this review was to provide an overview of the different pituitary tumour types in dogs and cats that have been reported in the literature. In dogs, the most common pituitary tumour type is the corticotroph adenoma, which can cause pituitary-dependent hypercortisolism. In cats, the most common pituitary tumour is the somatotroph adenoma, which can cause hypersomatotropism, and the second-most common is the corticotroph adenoma. A lactotroph adenoma has been described in one dog, while gonadotroph, thyrotroph and null cell adenomas have not been described in dogs or cats. Hormonally silent adenomas are likely underdiagnosed because they do not result in an endocrine syndrome. Tools used to classify pituitary tumours in humans, particularly immunohistochemistry for lineage-specific transcription factors, are likely to be useful to classify canine and feline pituitary tumours of unknown origin. Future studies are required to better understand the full range of pituitary adenoma pathology in dogs and cats and to determine whether certain adenoma subtypes behave more aggressively than others. Currently, the mechanisms that underlie pituitary tumorigenesis in dogs and cats are still largely unknown. A better understanding of the molecular background of these tumours could help to identify improved pituitary-targeted therapeutics.
Topics: ACTH-Secreting Pituitary Adenoma; Adenoma; Animals; Cat Diseases; Cats; Dog Diseases; Dogs; Growth Hormone-Secreting Pituitary Adenoma; Humans; Immunohistochemistry; Pituitary Neoplasms
PubMed: 33641809
DOI: 10.1016/j.tvjl.2021.105623 -
Neuroendocrinology 2020Craniopharyngioma (CP) is a rare embryonic malformation of the sellar/parasellar region with a low histological grade. Clinical manifestations are related to... (Review)
Review
Craniopharyngioma (CP) is a rare embryonic malformation of the sellar/parasellar region with a low histological grade. Clinical manifestations are related to hypothalamic/pituitary deficiencies, visual impairment, and increased intracranial pressure. Recent insight into the molecular pathogenesis of CP opens new perspectives on targeted therapy in papillary CP harboring BRAF-V600E mutations. Further research to elucidate pathogenic mechanisms and hopefully prevent hypothalamic involvement of CP is warranted. If the tumor is favorably localized, the therapy of choice is complete resection, with care taken to preserve the optical and hypothalamic functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), the recommended therapy is a limited hypothalamus-sparing surgical strategy followed by local irradiation. Surgical treatment strategies should be based on a multidisciplinary approach involving experienced teams. Centralizing the treatment of CP in experienced "centers of excellence" and multicenter-based networks for reference assessments should be considered to assure a high standard of treatment quality. CP recurrence and progression are frequent. Irradiation has proven effective in reducing recurrences and progression. Proton beam therapy, available in a wider range in the near future, will help to avoid radio-oncological side effects. Anatomical involvement and/or surgical lesions of posterior hypothalamic areas can result in serious sequelae that compromise quality of life (QoL), such as hypothalamic obesity and psychopathological symptoms. Novel insights into neuropsychological sequelae after CP occurrence should be the basis for the development of therapeutic neuropsychological interventions. CP should be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' clinical and QoL consequences by experienced multidisciplinary teams.
Topics: Craniopharyngioma; Humans; Pituitary Neoplasms
PubMed: 31678973
DOI: 10.1159/000504512 -
The New England Journal of Medicine Mar 2020
Review
Topics: Adenoma; Age Factors; Endocrine System Diseases; Female; Growth Hormone-Secreting Pituitary Adenoma; Humans; Hyperprolactinemia; Male; Pituitary ACTH Hypersecretion; Pituitary Neoplasms; Prolactin
PubMed: 32130815
DOI: 10.1056/NEJMra1810772