Germline mutation landscape of multiple endocrine neoplasia type 1 using full gene next-generation sequencing

Mirrored Metastatic Neuroendocrine Tumor in a Mother-Daughter Duo With Mutations in the MEN1 Gene

Multiple endocrine neoplasia (MEN) 1 syndrome may present with either of any or all neuroendocrine tumors (NETs), parathyroid and pituitary adenoma. There is a paucity of data on the intronic and exonic mutations in the MEN1 gene associated with the MEN1 syndrome. We present an interesting study of a mother-daughter duo of MEN1 who had a similar lesions distribution of metastatic NET and underwent genetic analysis to reveal a rare mutation in the MEN1 gene and both first-degree relatives presented with metastatic NET without any other syndromic manifestation of MEN1 syndrome. Both patients received peptide receptor radionuclide therapy.

Genotype-phenotype correlation in multiple endocrine neoplasia type 1

BACKGROUNDAmong patients with multiple endocrine neoplasia type 1 (MEN1), 80% develop duodenopancreatic neuroendocrine tumors (dpNETs), of whom 15%-25% die of metastasis. There is a need to identify biomarkers to predict aggressive disease. MEN1 genotype affords an attractive possibility as a biomarker, as it remains constant during life. Currently, patients are clinically diagnosed with MEN1 by the presence of ≥2 primary endocrine tumors (pituitary, parathyroid, and pancreas) or ≥1 primary endocrine tumor with a positive family history. From 10% to 30% of patients diagnosed clinically with MEN1 have no pathogenic germline MEN1 variants.METHODSThis was a retrospective study of 162 index patients or probands with genotype-positive and 47 with genotype-negative MEN1 enrolled from 1977 to 2022.RESULTSCompared with patients with genotype-negative disease, patients with genotype-positive disease were younger at diagnosis and had an increased frequency of recurrent parathyroid tumors, dpNETs, and angiofibromas or collagenomas. We propose a weighted scoring system to diagnose genotype-positive MEN1 based on clinical characteristics. No evidence of MEN1 mosaicism was seen in 30 tumors from 17 patients with genotype-negative MEN1. Patients with germline MEN1 variants in exons 2 and 3 had a reduced risk of distant metastases.CONCLUSIONThe clinical course of genotype-negative MEN1 is distinct from genotype-positive disease, raising uncertainty about the benefits of lifetime surveillance in patients with genotype-negative disease. MEN1 mosaicism is rare.TRIAL REGISTRATION ClinicalTrials.gov NCT04969926FUNDINGIntramural Research Program of National Institute of Diabetes and Digestive and Kidney Diseases, NIH (ZIA DK043006-46).

Multiple endocrine neoplasia type 4 (MEN4): a thorough update on the latest and least known men syndrome

PURPOSE

Multiple endocrine neoplasia type 4 (MEN4) is a rare multiglandular endocrine neoplasia syndrome, associated with a wide tumor spectrum but hallmarked by primary hyperparathyroidism, which represents the most common clinical feature, followed by pituitary (functional and non-functional) adenomas, and neuroendocrine tumors. MEN4 clinically overlaps MEN type 1 (MEN1) but differs from it for milder clinical features and an older patient's age at onset. The underlying mutated gene, CDKN1B, encodes the cell cycle regulator p27, implicated in cellular proliferation, motility and apoptosis. Given the paucity of MEN4 cases described in the literature, possible genotype-phenotype correlations have not been thoroughly assessed, and specific clinical recommendations are lacking. The present review provides an extensive overview of molecular genetics and clinical features of MEN4, with the aim of contributing to delineate peculiar strategies for clinical management, screening and follow-up of the last and least known MEN syndrome.

METHODS

A literature search was performed through online databases like MEDLINE and Scopus.

CONCLUSIONS

MEN4 is much less common that MEN1, tend to present later in life with a more indolent course, although involving the same primary organs as MEN1. As a consequence, MEN4 patients might need specific diagnostic and therapeutic approaches and a different strategy for screening and follow-up. Further studies are needed to assess the real oncological risk of MEN4 carriers, and to establish a standardized screening protocol. Furthermore, a deeper understanding of molecular genetics of MEN4 is needed in order to explore p27 as a novel therapeutic target.

Clinical profile and treatment outcomes among patients with sporadic and multiple endocrine neoplasia syndrome-related primary hyperparathyroidism

OBJECTIVE

Accurate demarcation between multiple endocrine neoplasia, type 1 (MEN1)- related primary hyperparathyroidism (MPHPT) and sporadic PHPT (SPHPT) is important to plan the management of primary parathyroid disease and surveillance for other endocrine and nonendocrine tumours. The objective of this study is to compare the clinical, biochemical and radiological features and surgical outcomes in patients with MPHPT versus SPHPT and to identify the predictors of MEN1 syndrome in PHPT.

DESIGN, PATIENTS AND MEASUREMENTS

This was an ambispective observationalstudy involving 251 patients with SPHPT and 23 patients with MPHPT evaluated at the endocrine clinic of All India Institute of Medical Sciences, New Delhi, India between January 2015 and December 2021.

RESULTS

The prevalence of MEN1 syndrome among patients with PHPT was 8.2% and a genetic mutation was identified by Sanger sequencing in 26.1% of patients with MPHPT. Patients with MPHPT were younger (p < .001), had lower mean serum calcium (p = .01) and alkaline phosphatase (ALP; p = .03) levels and lower bone mineral density (BMD) Z score at lumbar spine (p < .001) and femoral neck (p = .007). The prevalence of renal stones (p = .03) and their complications (p = .006) was significantly higher in MPHPT group. On multivariable analysis, factors predictive of MPHPT were hyperplasia on histopathology [OR 40.1, p < .001], ALP levels within reference range [OR 5.6, p = .02] and lumbar spine BMD [OR 0.39 per unit increase in Z score, p < .001].

CONCLUSIONS

Patients with MPHPT have more severe, frequent and early onset of bone and renal involvement despite milder biochemical features. A normal serum ALP, low BMD for age and gender at lumbar spine and histopathology evidence of hyperplasia are predictive factors for MEN1 syndrome in PHPT.

Cutaneous lesions and other non-endocrine manifestations of Multiple Endocrine Neoplasia type 1 syndrome

Background

Multiple Endocrine Neoplasia type 1 is a rare genetic syndrome mainly caused by mutations of MEN1 gene and characterized by a combination of several endocrine and non-endocrine manifestations. The objective of this study was to describe cutaneous lesions and other non-endocrine manifestations of MEN1 in a cohort of patients with familial (F) and sporadic (S) MEN1, compare the prevalence of these manifestations between the two cohorts, and investigate the correlation with MEN1 mutation status.

Methods

We collected phenotypic and genotypic data of 185 patients with F-MEN1 and S-MEN1 followed from 1997 to 2022. The associations between F-MEN1 and S-MEN1 or MEN1 mutation-positive and mutation-negative patients and non-endocrine manifestations were determined using chi-square or Fisher's exact tests or multivariate exact logistic regression analyses.

Results

The prevalence of angiofibromas was significantly higher in F-MEN1 than in S-MEN1 in both the whole (p < 0.001) and index case (p = 0.003) cohorts. The prevalence of lipomas was also significantly higher in F-MEN1 than in S-MEN1 (p = 0.009) and in MEN1 mutation-positive than in MEN1 mutation-negative (p = 0.01) index cases. In the whole cohort, the prevalence of lipomas was significantly higher in MEN1 mutation-positive compared to MEN1 mutation-negative patients (OR = 2.7, p = 0.02) and in F-MEN1 than in S-MEN1 (p = 0.03), only after adjustment for age. No significant differences were observed for the other non-endocrine manifestations between the two cohorts. Hibernoma and collagenoma were each present in one patient (0.5%) and meningioma and neuroblastoma in 2.7% and 0.5%, respectively. Gastric leiomyoma was present in 1.1% of the patients and uterine leiomyoma in 14% of women. Thyroid cancer, breast cancer, lung cancer, basal cell carcinoma, melanoma, and colorectal cancer were present in 4.9%, 2.7%, 1.6%, 1.6%, 2.2%, and 0.5% of the whole series, respectively.

Conclusions

We found a significantly higher prevalence of angiofibromas and lipomas in F-MEN1 compared with S-MEN1 and in MEN1 mutation-positive compared to MEN1 mutation-negative patients. In patients with one major endocrine manifestation of MEN1 , the presence of cutaneous lesions might suggest the diagnosis of MEN1 and a possible indication for genetic screening.

Clinical and molecular features of four Brazilian families with multiple endocrine neoplasia type 1

Objective

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant syndrome characterized by its clinical variability and complexity in diagnosis and treatment. We performed both clinical and molecular descriptions of four families with MEN1 in a follow-up at a tertiary center in Brasília.

Methods

From a preliminary review of approximately 500 medical records of patients with pituitary neuroendocrine tumor (PitNET) from the database of the Neuroendocrinology Outpatient Clinic of the University Hospital of Brasília, a total of 135 patients met the criteria of at least two affected family members. From this cohort, we have identified 34 families: only four with a phenotype of MEN1 and the other 30 families with the phenotype of familial isolated pituitary adenoma (FIPA). Eleven patients with a clinical diagnosis of MEN1 from these four families were selected.

Results

Variants in MEN1 gene were identified in all families. One individual from each family underwent genetic testing using targeted high-throughput sequencing (HTS). All patients had primary hyperparathyroidism (PHPT), and the second most common manifestation was PitNET. One individual had well-differentiated liposarcoma, which has been previously reported in a single case of MEN1. Three variants previously described in the database and a novel variant in exon 2 have been found.

Conclusions

The study allowed the genotypic and phenotypic characterization of families with MEN1 in a follow-up at a tertiary center in Brasília.

Multilevel Annotation of Germline MEN1 Variants of Synonymous, Nonsynonymous, and Uncertain Significance in Indian Patients With Sporadic Primary Hyperparathyroidism

Primary hyperparathyroidism (PHPT) is third most common endocrine disorder characterized by hypercalcemia with elevated or nonsuppressed parathyroid hormone levels by parathyroid tumors. Familial PHPT, as part of multiple endocrine type-1, occurs due to the germline mutation in the MEN1 gene. The involvement and the role of germline MEN1 variations in sporadic PHPT of Indian PHPT patients are unknown. Precise classifications of different types of MEN1 variations are fundamental for determining clinical relevance and diagnostic role. This prospective cohort study was performed on 82 patients with PHPT (with no clinical or history of MEN1) who underwent screening for MEN1 variations through Sanger sequencing. Multilevel computational analysis was performed to determine the structure-function relationship of synonymous, nonsynonymous, and variants of uncertain significance (VUS). Of the 82 PHPT patients, 42 (51%) had 26 germline MEN1 variants, including eight nonsynonymous, seven synonymous, nine VUS, one splice site, and one regulatory variation. Five most common germline variations (c.1838A>G, c.1817C>T, c.1525C>A, c.-35A>T, and c.250T>C) were observed in this study. c.-35A>T (5' untranslated region [UTR]) was associated with recurrence of PHPT (odds ratio [OR] = 5.4; p = 0.04) and subsequent detection of other endocrine tumors (OR = 13.6, p = 0.035). c.1525C>A was associated with multi glandular parathyroid tumor (OR = 13.6, p = 0.035). Align-Grantham variation and Grantham deviation (Align-GVGD), functional analysis through hidden Markov MODEL (FATHMM), and MutationTaster analysis reported the disease-specific potential of VUS and synonymous variations. Significant linkage disequilibrium was observed in c.1785G>A and c.1817C>T (r²  = 0.3859, p = 0.0001), c.1475C>G and c.1525C>A (r²  = 0.385, p = 0.0004), and c.1569T>C and c.1838A>G (r²  = 0.488, p = 0.0001). The detection of MEN1 variations, especially those with disease-specific potential, can prompt early screening for other MEN1-related tumors and disease recurrence. © 2022 American Society for Bone and Mineral Research (ASBMR).

Impact of parathyroidectomy on quality of life in multiple endocrine neoplasia type 1

BACKGROUND

Potential influences of parathyroidectomy (PTx) on the quality of life (QoL) in multiple endocrine neoplasia type 1-related primary hyperparathyroidism (HPT/MEN1) are unknown.

METHOD

Short Form 36 Health Survey Questionnaire was prospectively applied to 30 HPT/MEN1 patients submitted to PTx (20, subtotal; 10, total with autograft) before, 6 and 12 months after surgery. Parameters that were analyzed included QoL, age, HPT-related symptoms, general pain, comorbidities, biochemical/hormonal response, PTx type and parathyroid volume.

RESULTS

Asymptomatic patients were younger (30 vs 38 years; P = 0.04) and presented higher QoL scores than symptomatic ones: Physical Component Summary score (PCS) 92.5 vs 61.2, P = 0.0051; Mental Component Summary score (MCS) 82.0 vs 56.0, P = 0.04. In both groups, QoL remained stable 1 year after PTx, independently of the number of comorbidities. Preoperative general pain was negatively correlated with PCS (r = -0.60, P = 0.0004) and MCS (r = -0.57, P = 0.0009). Also, moderate/intense pain was progressively (6/12 months) more frequent in cases developing hypoparathyroidism. The PTx type and hypoparathyroidism did not affect the QoL at 12 months although remnant parathyroid tissue volume did have a positive correlation (P = 0.0490; r = 0.3625) to PCS 12 months after surgery. Patients with one to two comorbidities had as pre-PTx PCS (P = 0.0015) as 12 months and post-PTx PCS (P = 0.0031) and MCS (P = 0.0365) better than patients with three to four comorbidities.

CONCLUSION

A variable QoL profile was underscored in HPT/MEN1 reflecting multiple factors associated with this complex disorder as comorbidities, advanced age at PTx and presence of preoperative symptoms or of general pain perception. Our data encourage the early indication of PTx in HPT/MEN1 by providing known metabolic benefits to target organs and avoiding potential negative impact on QoL.

A Novel Isogenic Human Cell-Based System for MEN1 Syndrome Generated by CRISPR/Cas9 Genome Editing

Multiple endocrine neoplasia type 1 (MEN1) is a rare tumor syndrome that manifests differently among various patients. Despite the mutations in the MEN1 gene that commonly predispose tumor development, there are no obvious phenotype-genotype correlations. The existing animal and in vitro models do not allow for studies of the molecular genetics of the disease in a human-specific context. We aimed to create a new human cell-based model, which would consider the variability in genetic or environmental factors that cause the complexity of MEN1 syndrome. Here, we generated patient-specific induced pluripotent stem cell lines carrying the mutation c.1252G>T, D418Y in the MEN1 gene. To reduce the genetically determined variability of the existing cellular models, we created an isogenic cell system by modifying the target allele through CRISPR/Cas9 editing with great specificity and efficiency. The high potential of these cell lines to differentiate into the endodermal lineage in defined conditions ensures the next steps in the development of more specialized cells that are commonly affected in MEN1 patients, such as parathyroid or pancreatic islet cells. We anticipate that this isogenic system will be broadly useful to comprehensively study MEN1 gene function across different contexts, including in vitro modeling of MEN1 syndrome.

A germline c.1546dupC MEN1 mutation in an MEN1 family: A case report

RATIONALE

Multiple endocrine neoplasia type 1 (MEN1) is a rare tumor syndrome with an autosomal dominant inheritance, and genetic testing for MEN1 gene is important for both affected individuals and their relatives. We present a 2-person family affected by a germline c.1546dupC MEN1 mutation, and one of them had a full-spectrum of MEN-related endocrine tumors.

PATIENT CONCERNS

A female patient aged 32 years presented with jejunal ulcer perforation due to gastrinoma.

DIAGNOSES

We conducted genetic analysis and extensive biochemical/radiological evaluation for detecting other endocrine tumors. Multiple pancreatic neuroendocrine tumors (NETs), prolactinoma and primary hyperparathyroidism were diagnosed, and a frame-shift mutation, NM_130799.1:c.1546dupC (p.Arg516Profs∗15), was detected. One daughter of the proband, aged 12 years, had the same mutation for MEN1.

INTERVENTION

She underwent pancreatic surgery for pancreatic NETs and total parathyroidectomy for primary hyperparathyroidism.

OUTCOMES

After pancreatic surgery, long-term symptoms of epigastric soreness, acid belching, sweating, and palpitation in fasting were improved. Hypercalcemia was improved after parathyroidectomy and she was supplemented with oral calcium and vitamin D. Her daughter showed normal biochemical surveillance until 15 years of age.

LESSONS

We report 2 people in a family affected by MEN1 with the heterozygous germline c.1546dupC mutation, a variant that should be surveilled for early development of full-blown MEN1-associated endocrine tumors.

Clinical Profile and Mutations Associated with Multiple Endocrine Neoplasia-Type1 (MEN1) and Their First-Degree Relatives at Risk of Developing MEN1: A Prospective Study

Multiple Endocrine Neoplasia type-1 (MEN1) is an autosomal dominant disorder with a combined occurrence of tumours of parathyroid glands, pancreatic islets, and anterior pituitary. About 90% of these patients carry mutations in the MEN1 gene, though the spectrum is not well defined in India. Forty clinically suspected cases of MEN1 were enrolled prospectively over six years; 32 patients (23 index-cases and nine affected relatives) with≥2 classical endocrine tumours of MEN1 were considered definite, and eight were categorised as 'MEN1-like'. Details of their clinical presentation, treatment and mutational analysis including MEN1 gene, 3' and 5' untranslated regions (UTR) of MEN1, CDKN1B, and CaSR genes were collated. Asymptomatic first-degree relatives were also screened. Among the 32 definite MEN1 patients, all had primary hyperparathyroidism, 22 (68.7%) had gastroentero-pancreatic neuroendocrine tumours, and 21 (66%) had pituitary adenoma. Of the 23 definite index-cases, 13 (56.5%) carried mutations in the MEN1 gene. Five of nine affected first-degree relatives (55.5%), and four of 10 asymptomatic relatives (40%) also had MEN1 mutations. Seven of 10 MEN1 mutation-negative definite index-cases harboured p.V109G polymorphism in the CDKN1B gene. All eight MEN1-like cases were negative for mutations and large deletions in MEN1, mutations in 3' and 5' UTR of MEN1, CaSR and CDKN1B genes. The study has helped to clearly document the pattern of mutations among Indian MEN1 patients. However, the absence of MEN1 mutation in ~44% of cases and the presence of p.V109G polymorphism in CDKN1B gene raise the question whether such polymorphisms could independently contribute to pathogenesis.

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.

Giant Prolactinoma Causing Hydrocephalus and Intracranial Hypertension as First Manifestations of Multiple Endocrine Neoplasia Type 1

Context: Overall, giant prolactinomas are rare tumors (4%), especially those larger than 60 mm (1%). Despite the predominance of macroadenoma documented in multiple endocrine neoplasia type 1 (MEN1)-related prolactinoma, only three giant prolactinoma cases were described so far (size > 40 mm and prolactin > 1,000 ng/mL). None of them was larger than 60 mm or presented hydrocephalus or intracranial hypertension (ICH) as initial manifestation of MEN1. Case Description: A 21-years-old man presented with ICH as the first clinical manifestation of MEN1. He harbored a MEN1 germline mutation but refused periodic vigilance after normal hormonal screening at age 14 years. During investigation, magnetic resonance imaging (MRI) of the skull showed an expansive sellar/parasellar lesion (75 × 44 × 36 mm) with moderate to severe supratentorial obstructive hydrocephalus and an extremely high serum prolactin (PRL) of 10,800 ng/mL, without combined hypersecretion of other pituitary hormones. He was diagnosed with giant prolactinoma, and cabergoline was initiated. The patient evolved with early improvement of clinical complaints for hydrocephalus and ICH and PRL reached normal values (11 ng/mL) in association with significant tumoral shrinkage after 18 months on cabergoline. After 2 months of cabergoline, cerebrospinal fluid leakage was diagnosed and corrective surgery was provided. The mean dose of cabergoline was 3 mg/week throughout treatment. Conclusion: We reported the first case with hydrocephalus and ICH as the initial clinical manifestation of a giant prolactinoma in MEN1. From our knowledge, this is the largest MEN1-related prolactinoma reported so far. Notably, all four MEN1-related giant prolactinomas cases reported were younger than 21 years strengthening the importance to routine MEN1 genetic testing for prolactinoma in this age group. Also, they all had initial effective response with dopamine agonist ensuring this drug as first-line treatment for MEN1-related giant prolactinoma. However, the scarce number of treated patients and progression of cabergoline resistance in two of them suggest strict surveillance.

Could the Less-Than Subtotal Parathyroidectomy Be an Option for Treating Young Patients With Multiple Endocrine Neoplasia Type 1-Related Hyperparathyroidism?

Background: The surgical treatment of primary hyperparathyroidism (HPT) in patients with multiple endocrine neoplasia type 1 (MEN1) has evolved due the concern of permanent hypoparathyroidism. As the diagnosis has increased, the extent of operation has decreased. Most MEN1 patients requiring parathyroidectomy are younger than 50 years and they pose a difficult balance to achieve between persistent HPT and life-long hypoparathyroidism. The aim of the present study is to review our experience with a large series of patients with MEN1-related HPT (HPT/MEN1) treated at a single institution in order to find clues to a better treatment decision in these younger cases. Method: Retrospective analysis of consecutive HPT/MEN1 cases treated at a single institution with different operations: total parathyroidectomy and immediate forearm autograft (TPTX-AG), subtotal (STPTX), unintentional less than subtotal (U-LSTPTX) and intentional less than subtotal parathyroidectomy (I-LSTPTX). Results: Considering 84 initial cases operated on since 2011 (TPTX-AG, 39; STPTX, 22, U-LSTPTX, 13, and I-LSTPTX, 10), the rates of hypoparathyroidism were 30.8% (U-LSTPTX), 28.2% (TPTX-AG), 13.6% (STPTX), and 0% (I-LSTPTX). Two-thirds of them (68%; 57/84) were young (<50 years) or asdolescents. MIBI scan was more sensitive to show parathyroid glands and bilateral disease. Considering the concordance of MIBI and ultrasound for the possibility of unilateral clearance, it would be suitable to 22.6% of the cases. Intra-operative parathormone showed a significant decay even after unilateral exploration, but longer follow up is necessary. Overall, there were seven (4%) adolescents in 161 cases treated from 1987 to 2018, three underwent TPTX-AG and four had U-LSTPTX. Five are euparathyroid, one had mild recurrence, and one required a reoperation after 8 years due to the residual gland. Conclusions: Young patients are the most frequent candidates to parathyroidectomy. Less extensive procedures may be planned only if carefully reviewed preoperative imaging studies suggest a localized disease. Patients and their relatives should be fully informed of the risks and benefits during consent process. Future research with larger cohorts and long-term results are necessary to clarify if less than I-LSPTX or unilateral clearance are really adequate in selected groups of patients with HPT/MEN1 presenting lower volume of disease detected by preoperative imaging studies.