Clues For Genetic Anticipation In Multiple Endocrine Neoplasia Type 1

European Neuroendocrine Tumour Society (ENETS) 2023 guidance paper for nonfunctioning pancreatic neuroendocrine tumours

This ENETS guidance paper for well-differentiated nonfunctioning pancreatic neuroendocrine tumours (NF-Pan-NET) has been developed by a multidisciplinary working group, and provides up-to-date and practical advice on the management of these tumours. Using the extensive experience of centres treating patients with NF-Pan-NEN, the authors of this guidance paper discuss 10 troublesome questions in everyday clinical practice. Our many years of experience in this field are still being verified in the light of the results of new clinical, which set new ways of proceeding in NEN. The treatment of NF-Pan-NEN still requires a decision of a multidisciplinary team of specialists in the field of neuroendocrine neoplasms.

Update on the clinical management of multiple endocrine neoplasia type 1

This review provides an overview of novel insights in the clinical management of patients with Multiple Endocrine Neoplasia Type 1, focusing on the last decade since the last update of the MEN1 guidelines. With regard to Diagnosis: Mutation-negative patients with 2/3 main manifestations have a different clinical course compared to mutation-positive patients. As for primary hyperparathyroidism: subtotal parathyroidectomy is the initial procedure of choice. Current debate centres around the timing of initial parathyroidectomy as well as the controversial topic of unilateral clearance in young patients. For duodenopancreatic neuroendocrine tumours (NETs), the main challenge is accurate and individualized risk stratification to enable personalized surveillance and treatment. Thymus NETs remain one of the most aggressive MEN1-related tumours. Lung NETs are more frequent than previously thought, generally indolent, but rare aggressive cases do occur. Pituitary adenomas are most often prolactinomas and nonfunctioning microadenomas with an excellent prognosis and good response to therapy. Breast cancer is recognized as part of the MEN1 syndrome in women and periodical screening is advised. Clinically relevant manifestations are already seen at the paediatric age and initiating screening in the second decade is advisable. MEN1 has a significant impact on quality of life and US data show a significant financial burden. In conclusion, patient outcomes have improved, but much is still to be achieved. For care tailored to the needs of the individual patient and improving outcomes on an individual basis, studies are now needed to define predictors of tumour behaviour and effects of more individualized interventions.

Thymic neuroendocrine tumors in patients with multiple endocrine neoplasia type 1

OBJECTIVE

MEN1 is associated with an increased risk of developing tumors in different endocrine organs. Neuroendocrine tumors of the thymus (TNETs) are very rare but often have an aggressive nature. We evaluated patients with MEN1 and TNET in three university hospitals in Finland.

DESIGN/METHODS

We evaluated patient records of 183 MEN1-patients from three university hospitals between the years 1985-2019 with TNETs. Thymus tumor specimens were classified according to the new WHO 2021 classification of TNET. We collected data on treatments and outcomes of these patients.

RESULTS

There were six patients (3.3%) with MEN1 and TNET. Five of them had the same common gene mutation occurring in Finland. They originated from common ancestors encompassing two pairs of brothers from sequential generations. The mean age at presentation of TNET was 44.7 ± 11.9 years. TNET was classified as atypical carcinoid (AC) in five out of six patients. One patient had a largely necrotic main tumor with very few mitoses and another nodule with 25 mitoses per 2 mm², qualifying for the 2021 WHO diagnosis of large cell neuroendocrine carcinoma (LCNEC). In our patients, the 5-year survival of the TNET patients was 62.5% and 10-year survival 31.3%.

CONCLUSION

In this study, TNETs were observed in one large MEN1 founder pedigree, where an anticipation-like earlier disease onset was observed in the most recent generation. TNET in MEN1 patients is an aggressive disease. The prognosis can be better by systematic screening. We also show that LCNEC can be associated with TNET in MEN1 patients.

MEN1 Surveillance Guidelines: Time to (Re)Think?

Clinical practice guidelines for patients with multiple endocrine neoplasia type 1 (MEN1) recommend a variety of surveillance options. Given progress over the past decade in this area, it is timely to evaluate their ongoing utility. MEN1 is characterized by the development of synchronous or asynchronous tumors affecting a multitude of endocrine and nonendocrine tissues, resulting in premature morbidity and mortality, such that the rationale for undertaking surveillance screening in at-risk individuals appears robust. Current guidelines recommend an intensive regimen of clinical, biochemical, and radiological surveillance commencing in early childhood for those with a clinical or genetic diagnosis of MEN1, with the aim of early tumor detection and treatment. Although it is tempting to assume that such screening results in patient benefits and improved outcomes, the lack of a strong evidence base for several aspects of MEN1 care, and the potential for iatrogenic harms related to screening tests or interventions of unproven benefit, make such assumptions potentially unsound. Furthermore, the psychological as well as economic burdens of intensive screening remain largely unstudied. Although screening undoubtedly constitutes an important component of MEN1 patient care, this perspective aims to highlight some of the current uncertainties and challenges related to existing MEN1 guidelines with a particular focus on the role of screening for presymptomatic tumors. Looking forward, a screening approach that acknowledges these limitations and uncertainties and places the patient at the heart of the decision-making process is advocated.

Initiating Pancreatic Neuroendocrine Tumor (pNET) Screening in Young MEN1 Patients: Results From the DutchMEN Study Group

CONTEXT

Nonfunctioning pancreatic neuroendocrine tumors (NF-pNETs) are highly prevalent and constitute an important cause of mortality in patients with multiple endocrine neoplasia type 1 (MEN1). Still, the optimal age to initiate screening for pNETs is under debate.

OBJECTIVE

The aim of this work is to assess the age of occurrence of clinically relevant NF-pNETs in young MEN1 patients.

METHODS

Pancreatic imaging data of MEN1 patients were retrieved from the DutchMEN Study Group database. Interval-censored survival methods were used to describe age-related penetrance, compare survival curves, and develop a parametric model for estimating the risk of having clinically relevant NF-pNET at various ages. The primary objective was to assess age at occurrence of clinically relevant NF-pNET (size ≥ 20 mm or rapid growth); secondary objectives were the age at occurrence of NF-pNET of any size and pNET-associated metastasized disease.

RESULTS

Five of 350 patients developed clinically relevant NF-pNETs before age 18 years, 2 of whom subsequently developed lymph node metastases. No differences in clinically relevant NF-pNET-free survival were found for sex, time frame, and type of MEN1 diagnosis or genotype. The estimated ages (median, 95% CI) at a 1%, 2.5%, and 5% risk of having developed a clinically relevant tumor are 9.5 (6.5-12.7), 13.5 (10.2-16.9), and 17.8 years (14.3-21.4), respectively.

CONCLUSION

Analyses from this population-based cohort indicate that start of surveillance for NF-pNETs with pancreatic imaging at age 13 to 14 years is justified. The psychological and medical burden of screening at a young age should be considered.

Multiple Endocrine Neoplasia Type 1: Latest Insights

Multiple endocrine neoplasia type 1 (MEN1), a rare tumor syndrome that is inherited in an autosomal dominant pattern, is continuing to raise great interest for endocrinology, gastroenterology, surgery, radiology, genetics, and molecular biology specialists. There have been 2 major clinical practice guidance papers published in the past 2 decades, with the most recent published 8 years ago. Since then, several new insights on the basic biology and clinical features of MEN1 have appeared in the literature, and those data are discussed in this review. The genetic and molecular interactions of the MEN1-encoded protein menin with transcription factors and chromatin-modifying proteins in cell signaling pathways mediated by transforming growth factor β/bone morphogenetic protein, a few nuclear receptors, Wnt/β-catenin, and Hedgehog, and preclinical studies in mouse models have facilitated the understanding of the pathogenesis of MEN1-associated tumors and potential pharmacological interventions. The advancements in genetic diagnosis have offered a chance to recognize MEN1-related conditions in germline MEN1 mutation-negative patients. There is rapidly accumulating knowledge about clinical presentation in children, adolescents, and pregnancy that is translatable into the management of these very fragile patients. The discoveries about the genetic and molecular signatures of sporadic neuroendocrine tumors support the development of clinical trials with novel targeted therapies, along with advancements in diagnostic tools and surgical approaches. Finally, quality of life studies in patients affected by MEN1 and related conditions represent an effort necessary to develop a pharmacoeconomic interpretation of the problem. Because advances are being made both broadly and in focused areas, this timely review presents and discusses those studies collectively.