The multiple endocrine neoplasia (MEN) workshops had their beginnings at Queen’s University in Kingston, Ontario in June 1984. This initial meeting brought clinicians and scientists together to focus on mapping the gene for multiple endocrine neoplasia type 2 (MEN2). These efforts culminated in the identification of the RET protooncogene as the causative gene a decade later. Over the next 35 years there were a total of 16 international workshops focused on the several MEN syndromes. Importantly, these workshops were instrumental in efforts to define the molecular basis for multiple endocrine neoplasia type 1 (MEN1), MEN2, von Hippel-Lindau disease (VHL), Carney Complex, hereditary pheochromocytoma and hyperparathyroidism. In this same spirit some 150 scientists and clinicians met at MD Anderson Cancer Center, 27–29 March 2019, for the 16th International Workshop on Multiple Endocrine Neoplasia (MEN2019). Appropriate to its location in a cancer centre, the workshop focused on important issues in the causation and treatment of malignant aspects of the MEN syndromes: medullary thyroid carcinoma, pancreatic neuroendocrine tumours, malignant pheochromocytoma and parathyroid carcinoma. Workshops at the meeting focused on a better understanding of how the identified molecular defects in these genetic syndromes lead to transformation, how to apply targeted kinase inhibitors and immunotherapy to treat these tumours and important clinical management issues. This issue of Endocrine-Related Cancer describes these discussions and recommendations.
Elizabeth Grubbs, Daniel Halperin, Steven G Waguespack, and Robert F Gagel
Yulong Li and William F Simonds
Familial syndromes of hyperparathyroidism, including multiple endocrine neoplasia type 1 (MEN1), multiple endocrine neoplasia type 2A (MEN2A), and the hyperparathyroidism-jaw tumor (HPT-JT), comprise 2–5% of primary hyperparathyroidism cases. Familial syndromes of hyperparathyroidism are also associated with a range of endocrine and nonendocrine tumors, including potential malignancies. Complications of the associated neoplasms are the major causes of morbidities and mortalities in these familial syndromes, e.g., parathyroid carcinoma in HPT-JT syndrome; thymic, bronchial, and enteropancreatic neuroendocrine tumors in MEN1; and medullary thyroid cancer and pheochromocytoma in MEN2A. Because of the different underlying mechanisms of neoplasia, these familial tumors may have different characteristics compared with their sporadic counterparts. Large-scale clinical trials are frequently lacking due to the rarity of these diseases. With technological advances and the development of new medications, the natural history, diagnosis, and management of these syndromes are also evolving. In this article, we summarize the recent knowledge on endocrine neoplasms in three familial hyperparathyroidism syndromes, with an emphasis on disease characteristics, molecular pathogenesis, recent developments in biochemical and radiological evaluation, and expert opinions on surgical and medical therapies. Because these familial hyperparathyroidism syndromes are associated with a wide variety of tumors in different organs, this review is focused on those endocrine neoplasms with malignant potential.
Guido Rindi and Frediano Inzani
Neuroendocrine neoplasia is described in almost every tissue, either in the pure endocrine organs, the nerve structures or in the so-called diffuse neuroendocrine system. The current nomenclature contains time-honored, widely accepted definitions; however, it is different according to anatomical sites. Diverse definitions may generate confusion and non-standard patient management. The International Agency for Research on Cancer – World Health Organization (IARC-WHO) proposed a framework for universal classification of neuroendocrine neoplasia. Evidence indicates that neuroendocrine cancer is composed by cells with a distinctive phenotype characterized by the expression of general and specific neuroendocrine markers. The neuroendocrine phenotype is indicated as descriptor of a unique cancer category, now recommended for all organs as neuroendocrine neoplasm. Evidence indicates that neuroendocrine neoplasia may be well or poorly differentiated, with diverse incidence and prevalence in different organs. It is proposed that the well-differentiated neoplasm is universally defined as neuroendocrine tumor (NET) and the poorly differentiated as neoplasm neuroendocrine carcinoma (NEC). Evidence indicates that a cancer grading tool based on a proliferation measure by mitotic count, Ki67 % and/or necrosis assessment is useful to predict NET patient behavior. It is proposed to utilize this tool for grading NET universally, with site-specific cut-offs to be defined. It is also acknowledged that significant biological site-specific differences exist. It is recommended that current pathology reports contain this classification together with the current traditional classifiers. This IARC-WHO common classification framework for neuroendocrine neoplasm aims at uniformizing nomenclature toward different organs and at fostering the definition of a similar site-specific gene signature.
Pamela Brock, Jennifer L Geurts, Paulien Van Galen, Erica Blouch, James Welch, Amy Kunz, Lauren Desrosiers, Jennifer Gauerke, and Samuel Hyde
The Genetic Counseling Working Group from the 16th International Workshop on Multiple Endocrine Neoplasia (MEN 2019) convened to discuss contemporary challenges and opportunities in the area of genetic counseling for individuals and families affected by hereditary endocrine neoplasia syndromes. As healthcare professionals with multidisciplinary training in human genetics, risk assessment, patient education, psychosocial counseling, and research methodology, genetic counselors bring a unique perspective to working toward addressing these challenges and identifying their subsequent opportunities. This Working Group focused on the following broad areas: (1) genetic counseling resources for endocrine neoplasias, (2) candidate gene discovery, (3) implications of increasingly sensitive and expansive genetic testing technologies for both the germline and the tumors, and (4) situating clinical diagnoses for hereditary endocrine neoplasia syndromes in the context of present-day knowledge.
P H Kann, E Balakina, D Ivan, D K Bartsch, S Meyer, K-J Klose, Th Behr, and P Langer
Endoscopic ultrasound (EUS) enables detection and localization of pancreatic neuroendocrine tumours. Even small tumours down to a diameter of 1–2 mm can be visualized. Since such small tumours usually cannot be detected by computed tomography (ct), magnetic resonance imaging (mri) and somatostatin receptor scintigraphy (srs), and experience with EUS imaging is limited, there is no clear evidence for clinical management in multiple endocrine neoplasia type 1 (MEN1). Knowledge about the natural course of growth and metastatic distribution is mandatory to come to appropriate clinical decisions and guidelines. This prospective study was aimed to assess the natural course of small (<15 mm) neuroendocrine pancreatic tumours without clinical symptoms due to endocrine activity or mechanical problems and without clear indication for surgical therapy in MEN1 by EUS.
A total of 82 asymptomatic tumours <15 mm (5.9 ± 3.2 mm diameter at baseline) in 20 patients with MEN1-disease (8 female/12 male, 43 ± 13 years) were studied over a period of 20 ± 12 months (33.8 patient years, 106.7 tumour years) by EUS. Change in largest diameter of each tumour and annual tumour incidence rate in the patients’ cohort were calculated.
Increase of largest tumour diameter was found to be 1.3 ± 3.2% per month, annual tumour incidence rate 0.62 new tumours per patient year. In one patient, rapid progressive pancreatic manifestation of MEN1 was observed. There was no evidence in ct and/or srs and/or mri for metastatic disease in all patients. Only 4/84 (4.8%) pancreatic tumours could be visualized by computed tomography, 5/79 (6.3%) by somatostatin receptor imaging and 4/39 (10.3%) by magnetic resonance imaging.
Small asymptomatic neuroendocrine pancreatic tumours in MEN1 usually seem to grow slowly. Annual tumour incidence rate is low. However, faster growing tumours and patients with rapidly progressive disease can be observed. Risk for obvious metastatic disease from asymptomatic neuroendocrine pancreatic tumours <15 mm in MEN1 seems to be low.
S M Sadowski, G Cadiot, E Dansin, P Goudet, and F Triponez
Multiple endocrine neoplasia type 1 (MEN1) is a hereditary autosomal dominant disorder associated with numerous neuroendocrine tumors (NETs). Recent advances in the management of MEN1 have led to a decrease in mortality due to excess hormones; however, they have also led to an increase in mortality from malignancy, particularly NETs. The main challenges are to localize these tumors, to select those that need therapy because of the risk of aggressive behavior and to select the appropriate therapy associated with minimal morbidity. This must be applied to a hereditary disease with a high risk of recurrence. The overall aim of management in MEN1 is to ensure that the patient remains disease- and symptom-free for as long as possible and maintains a good quality of life. Herein, we review the changes that occurred in the last 20 years in the surgical management of MEN1-associated functional and non-functional pancreatico-duodenal NETs and thymic and bronchial NETs.
Jerena Manoharan, Max B Albers, and Detlef K Bartsch
Prospective randomized data are lacking, but current clinical expert guidelines recommend annual screening examinations, including laboratory assessments and various imaging modalities (e.g. CT, MRI, scintigraphy and EUS) for patients with multiple endocrine neoplasia type 1 (MEN1). Routine screening is proposed to detect and localize neuroendocrine manifestations as early as possible. The goal is timely intervention to improve quality of life and to increase life expectancy by preventing the development of life-threatening hormonal syndromes and/or metastatic disease. In recent years, some studies compared different and new imaging methods regarding their sensitivity and utility in MEN1 patients. This present article reviews the proposed diagnostic tools for MEN1 screening as well as potential future perspectives.
Luis V Syro, Fabio Rotondo, Leon D Ortiz, and Kalman Kovacs
Temozolomide is an alkylating chemotherapeutic agent used in malignant neuroendocrine neoplasia, melanoma, brain metastases and an essential component of adjuvant therapy in the treatment of glioblastoma multiforme and anaplastic astrocytoma. Since 2006, it has been used for the treatment of pituitary carcinomas and aggressive pituitary adenomas. Here, we discuss the current indications and results of temozolomide therapy in pituitary tumors, as well as frequently asked questions regarding temozolomide treatment, duration of therapy, dosage, tumor recurrence and resistance.
Joanna Grey and Kym Winter
Multiple endocrine neoplasia type 2 (MEN2) refers to the autosomal-dominant neuroendocrine tumour syndromes, MEN type 2A (MEN2A) and MEN type 2B (MEN2B). They are typified by the development of medullary thyroid cancer (MTC), phaeochromocytoma and parathyroid hyperplasia in MEN2A and MTC, phaeochromocytomas, ganglioneuromatosis and skeletal abnormalities in MEN2B. The aggressiveness of MTC is variable according to genotype, and although it is still the major cause of mortality in both conditions, prognosis has improved dramatically in those diagnosed and treated at a young age thanks to predictive genetic testing. Nevertheless, metastatic MTC, ganglioneuromatosis and a variety of other negative clinical and psychosocial impacts on quality of life and/or prognosis in MEN2 persist. In the absence, at the time of writing, of any large-scale research into quality of life specifically in MEN2, this review includes data from patient surveys and anonymised patient anecdotes from the records of the Association for Multiple Endocrine Neoplasia Disorders (AMEND), for whom the authors work. We recommend that these patients are cared for only in centres of expertise able to provide expert diagnosis, treatment and continuity of care, including psychological and transition support. Only in this way can the clinical advances of the last two and half decades be built upon further to ensure that the care of these complex, lifelong patients can be considered truly holistic.
Zijie Feng, Jian Ma, and Xianxin Hua
There is a trend of increasing prevalence of neuroendocrine tumors (NETs), and the inherited multiple endocrine neoplasia type 1 (MEN1) syndrome serves as a genetic model to investigate how NETs develop and the underlying mechanisms. Menin, encoded by the MEN1 gene, at least partly acts as a scaffold protein by interacting with multiple partners to regulate cellular homeostasis of various endocrine organs. Menin has multiple functions including regulation of several important signaling pathways by controlling gene transcription. Here, we focus on reviewing the recent progress in elucidating the key biochemical role of menin in epigenetic regulation of gene transcription and cell signaling, as well as posttranslational regulation of menin itself. In particular, we will review the progress in studying structural and functional interactions of menin with various histone modifiers and transcription factors such as MLL, PRMT5, SUV39H1 and other transcription factors including c-Myb and JunD. Moreover, the role of menin in regulating cell signaling pathways such as TGF-beta, Wnt and Hedgehog, as well as miRNA biogenesis and processing will be described. Further, the regulation of the MEN1 gene transcription, posttranslational modifications and stability of menin protein will be reviewed. These various modes of regulation by menin as well as regulation of menin by various biological factors broaden the view regarding how menin controls various biological processes in neuroendocrine organ homeostasis.