From pituitary adenoma to pituitary neuroendocrine tumor (PitNET): an International Pituitary Pathology Club proposal

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.

Validation of a clinicopathological score for the prediction of post-surgical evolution of pituitary adenoma: retrospective analysis on 566 patients from a tertiary care centre

“…Pituitary adenomas (PAs) are relatively common intracranial tumours arising from the adenohypophysis and accounting for 10-15% of all intracranial neoplasms (1,2,3,4). Although typically benign under a histological point of view, they can exhibit an aggressive clinical and radiological behaviour, characterised by rapid growth with gross invasion of the surrounding tissues, together with resistance, or early recurrence, after treatment (4,5,6,7,8).…”

“…Although typically benign under a histological point of view, they can exhibit an aggressive clinical and radiological behaviour, characterised by rapid growth with gross invasion of the surrounding tissues, together with resistance, or early recurrence, after treatment (4,5,6,7,8). Therefore, it has been recently proposed to rename these lesions as pituitary neuroendocrine tumours (PitNET) (3). Only rarely they metastasise through the cerebrospinal fluid or systemically and are then considered 'pituitary carcinomas' (6,7).…”

Multiple Endocrine Neoplasia and Hyperparathyroid-Jaw Tumor Syndromes: Clinical Features, Genetics, and Surveillance Recommendations in Childhood

“…Multiple Endocrine Neoplasia Type 1 (MEN1, OMIM 131100) was initially identified as early as 1903 (2), and formally defined by Underhal and Werner nearly 50 years later (3,4) as an autosomal-dominant familial disorder characterized by 1) primary hyperparathyroidism (PHPT) and hypercalcemia resulting from parathyroid adenomas (generally multi-glandular); 2) hormone-secreting or non-secreting pancreatic islet tumors (commonly gastrinomas and rarely insulinomas, VIPomas, glucagonomas or other neoplasms); and 3) anterior pituitary neuroendocrine tumors (PitNETs), predominantly prolactinomas, less frequently, growth hormone secreting adenomas (5,6) and rarely, other PitNETs (which constitute <5% of pituitary tumors in MEN1)(7). Angiofibromas, lipomas and collagenomas (8–10) are common dermatologic manifestations of MEN1, and adrenocortical adenomas are identified in 35% of patients with MEN1 (11).…”

ALK7 expression in prolactinoma is associated with reduced prolactin and increased proliferation

“…Pituitary tumour is the second most common primary brain tumour in adults (Asa & Ezzat 2002, Asa et al 2017. Pituitary tumours are considered as benign, yet their deleterious effects are multiple, ranging from visual disturbance, headaches and infertility through the alteration of metabolic functions due to the hormone they secrete (Asa & Ezzat 2002, Asa et al 2017. While most of pituitary tumours have a slow rate of growth, a number of them exhibit an aggressive progression with recurrences.…”

“…While most of pituitary tumours have a slow rate of growth, a number of them exhibit an aggressive progression with recurrences. The classification of pituitary neoplasms is misleading because of the simplistic distinction between adenoma and carcinoma, based on a metastatic capacity and a poor predictive value of mitoses and Ki67 or p53 expression (Asa et al 2017). In addition, the current classification of anterior pituitary neoplasms does not reflect the clinical spectrum of behaviour such as invasion, regrowth of proliferative lesions and persistence of hormone hypersecretion (Raverot et al 2017).…”