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Background: MEN1 mutations can inactivate or disrupt menin function and are leading to multiple endocrine neoplasia type 1, a rare heritable tumor syndrome. Case presentation: We report on a MEN1 family with a novel heterozygous germline mutation, c.674delG; p.Gly225Aspfs*56 in exon 4 of the MEN1 gene. Diagnosis and clinical phenotyping of MEN1 was established by laboratory tests, ultrasound, biopsy, MRI imaging and endosonography. The clinical course of the disease was followed in the index patient and her family members for eight years. The mutation was associated with distinct clinical phenotypes in the index patient and three family members harboring p.Gly225Aspfs*56. Family members affected showed primary hyperparathyroidism but variable patterns of associated endocrine tumors, adrenal cortical adenomas, prolactinoma, multifocal pancreatic neuroendocrine tumors, insulinoma and nonsecretory neuroendocrine tumors of the pancreas. The mutation c.674delG; p.Gly225Aspfs*56 leads to a frameshift from codon 225 with early truncation of the menin protein. In silico analysis predicts loss of multiple protein-menin interactions in p.Gly225Aspfs*56, potentially rendering menin insufficient to control cell division and replication. However, no aggressive neuroendocrine tumors were observed in the follow-up of this family. Conclusions: We report a novel heterozygous MEN1 frameshift mutation, potentially causing (at least partial) inactivation of menin tumor suppression potential but lacking a genotype–phenotype correlation. Our study highlights the importance of personalized care with appropriate testing and counseling in MEN1 families. [ABSTRACT FROM AUTHOR]

Background: Multiple endocrine neoplasia type 1 (MEN1) is a hereditary cancer syndrome caused by germline variants in the MEN1 gene located on chromosome 11q13. We found a Chinese woman who had a pancreatic tumor, parathyroid tumor, adrenal tumor, and suspicion of gastrinoma. Case presentation: The proband and her immediate family members underwent genetic detection. The results showed that two of the proband's six relatives had the same variants as the proband, and her sister also had the typical symptoms of MEN1. However, the first- and second-time genetic detection results showed that they were homozygous variants, which did not conform to Mendelian inheritance laws. Multiplex ligation-dependent probe amplification (MLPA) was used to rule out homozygous variants caused by a deletion of gene fragments in the proband and her immediate family members. The MLPA results showed that the gene deletion was absent in the MEN1. The results from the third genetic detection (redesigned the primer) showed that they had a heterozygous variant. A new MEN1 germline variant [c.201delC (p.Ala68Profs*51)], which could induce MEN1, was found in this study. Conclusions: This newly identified germline variant could improve the identification of clinical phenotypes and the early diagnosis of MEN1. Clinician should consider the present of situation that intron variant causing detection error. Re-designing the primers close to the variant site for gene detection could avoid this situation. [ABSTRACT FROM AUTHOR]

Parathyroidectomy for primary hyperparathyroidism (pHPT) is safely performed in the outpatient setting in the adult population. However, concern that children and adolescents have higher complication rates and are unable to recognize and communicate symptoms of hypocalcemia has limited same-day discharges in the pediatric population. Nineteen patients aged 8–18 years (14.1 ± 0.7) underwent outpatient parathyroidectomy for pHPT by a single high-volume endocrine surgeon from 2002–2020. Patient demographics, disease, operations, and complications were reviewed. Sixteen of 19 patients were symptomatic with fatigue (62.5%), joint pain (37.5%) and nephrolithiasis (18.7%) most common. Mean preoperative Ca and PTH were 11.7 ± 0.3 mg/dL and 102.3 ± 11.8pg/mL, respectively. Ten of 19 had a single adenoma and 9 had multigland hyperplasia including one MEN1 and one MEN2A patient. We performed 11 four-gland explorations, 8 unilateral parathyroidectomies; including 9 transcervical thymectomies, 1 total thyroidectomy, and 1 bilateral central neck dissection. Mean 6-month postoperative Ca and PTH levels were 9.5 ± 0.3 mg/dL (range 7.3–10.3) and 29±5.0pg/mL (range 6.3–77), respectively. One patient developed permanent hypoparathyroidism and 1 had temporary hypocalcemia. No temporary or permanent hoarseness, unplanned same-day admission, wound complications, or Emergency Department visits occurred. Outpatient parathyroidectomy can be safely and effectively performed in pediatric patients with primary HPT. Treatment Study, Level III. [ABSTRACT FROM AUTHOR]

Abstract Background Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited syndrome that concurrently involves various endocrine glands. We report a rare case of MEN1 in a 43-year-old man whose first manifestation was an asymptomatic mediastinal mass. Case presentation A 13-cm-sized mediastinal mass was diagnosed as an atypical thymic carcinoid by computed tomography and percutaneous needle biopsy. In addition, hypercalcemia from a left inferior parathyroid hyperplasia, and a non-functioning gastric neuroendocrine tumor seen on esophagogastroduodenoscopy were found. Therefore, the patient was clinically diagnosed with MEN1 syndrome, and underwent surgical resection of thymic carcinoid tumor after pre-operative concurrent chemoradiation therapy to decrease tumor size and volume. Parathyroid lesion and gastric neuroendocrine tumor were also removed. Finally, a MEN1 gene mutation was observed in the patient and his 7-year-old son. Conclusion Despite its rare occurrence, thymic carcinoid tumor should be considered as a MEN1-associated tumor and necessitates screening of other endocrine glands. Thymic carcinoid tumor carries a poor prognosis in patients with MEN1, and thus it needs to be carefully monitored even after radical excision.

Primary non‐functional pancreatic neuroendocrine tumors (NF‐PanNETs) are a heterogeneous group of neuroendocrine neoplasms that display highly variable clinical behavior. Therefore, NF‐PanNETs often present clinical teams with a dilemma: the uncertain metastatic potential of the tumor has to be weighed against the morbidity associated with surgical resection. Thus, rather than utilizing current radiologic thresholds, there is an urgent need for improved prognostic biomarkers. Recent studies aimed at understanding the epigenetic underpinnings of NF‐PanNETs have led to the identification of tumor subgroups based on histone modification and DNA methylation patterns. These molecular profiles tend to resemble the cellular origins of PanNETs. Subsequent retrospective analyses have demonstrated that these molecular signatures are of prognostic value and, importantly, may be useful in the preoperative setting. These studies have highlighted that sporadic NF‐PanNETs displaying biomarkers associated with disease progression and poor prognosis, such as alternative lengthening of telomeres, inactivating alpha thalassemia/mental retardation X‐linked (ATRX) or death domain‐associated protein (DAXX) gene mutations, or copy number variations, more often display alpha cell characteristics. Conversely, NF‐PanNETs with beta cell characteristics often lack these unfavorable biomarkers. Alternative lengthening of telomeres, transcription factor protein expression, and possibly DNA methylation can be assessed in endoscopic ultrasound‐guided tumor biopsies. Prospective studies focusing on cell‐of‐origin and epigenetic profile‐driven decision making prior to surgery are likely to be routinely implemented into clinical practice in the near future. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

MEN1 mutation causes pancreatic neuroendocrine neoplasia and benign malignancies of the parathyroid, the adrenal cortex and pituitary gland. The transcriptional activity of its product menin promotes the expression of genes deputed to several cellular mechanism including cell death. Here, we focused on its implication in the activation of the initiator and executioner caspases after staurosporine mediated cell death in 2D and 3D human and murine cell models. The administration of staurosporine, a well-known inducer of apoptotic cell death, caused a significant reduction of BON1, QGP1 and HPSC2.2 cell viability. The transient knockdown of MEN1, performed by using a specific siRNA, caused a significant down-regulation of CDKN1A and TP53 transcripts. The treatment with 1 µM of staurosporine caused also a significant down-regulation of MEN1 and was able to restore the basal expression of TP53 only in QGP1 cells. Transient or permanent MEN1 inactivation caused a decrease of caspase 8 activity in BON1, HPSC2.2 cells and MEN1−/− MEFs treated with staurosporine. Caspase 3/7 activity was suppressed after administration of staurosporine in MEN1 knocked down HPSC2.2 and MEN1−/− MEFs as well. The cleaved caspase 8 and caspase 3 decreased in human cells after MEN1 knockdown and in MEN1−/− MEFs. The treatment with staurosporine caused a reduction of the size of MEN1+/+ MEFs spheroids. Instead, MEN1−/− MEFs spheroids did not show any significant reduction of their size. In conclusion, MEN1 controls the activity of the initiator caspase 8 and the executioner caspase 3 in human and murine cells. Restoring of a functional MEN1 and interfering with the apoptotic mechanism could represent a future strategy for the treatment of MEN1-related malignancies. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: Data regarding vitamin D status in patients affected by gastroenteropancreatic (GEP) neuroendocrine tumor (NET) are limited and often showing contrasting results. The aim of the study was to evaluate the incidence of vitamin D deficiency (<20 ng/mL) in GEP-NET patients and compare the 25-hydroxyvitamin D (25(OH)D) levels with clinicopathological parameters and clinical outcome. Methods: A retrospective cross-sectional study including 75 low grade (G1-G2) GEP-NETs and 123 healthy controls matched for age, sex, and body mass index, was performed. Results: GEP-NET patients had significantly lower 25(OH)D levels compared to controls (17.9 ± 7.8 vs 24.2 ± 7.7 ng/mL, p < 0.0001). Ileal NETs were associated to lower 25(OH)D levels compared to other primary tumor sites (p = 0.049) and small bowel resection posed a significant increased risk of severe vitamin D deficiency (OR = 2.81, 95% CI = 1.25–3.37, p = 0.018). No correlation with somatostatin analogs treatment was found. 25(OH)D levels were significantly lower in G2 compared to G1 GEP-NETs (15.6 ± 7.8 vs 19.9 ± 7.4 ng/mL, p = 0.016) and in patients with progressive disease (12.6 ± 5.7 ng/mL) compared to those with stable disease (mean 21.5 ± 8.2 ng/mL, p = 0.001) or tumor free after surgery (19.6 ± 7.3 ng/mL, p = 0.002). Patients with vitamin D deficiency and insufficiency had shorter progression-free survival compared to those with sufficiency (p = 0.014), whereas no correlation was found with disease-specific survival. Conclusions: Vitamin D deficiency is highly prevalent among GEP-NETs and could be associated with high tumor grade and disease progression. Therefore, the monitoring of 25(OH)D levels is relevant in these patients and vitamin D supplementation should be considered in the management of GEP-NET patients with vitamin D deficiency or insufficiency. [ABSTRACT FROM AUTHOR]

Abetted by widespread usage of acid-suppressing proton pump inhibitors (PPIs), the mitogenic actions of the peptide hormone gastrin are being revisited as a recurring theme in various gastrointestinal (GI) malignancies. While pathological gastrin levels are intricately linked to hyperplasia of enterochromaffin-like cells leading to carcinoid development, the signaling effects exerted by gastrin on distinct cell types of the gastric mucosa are more nuanced. Indeed, mounting evidence suggests dichotomous roles for gastrin in both promoting and suppressing tumorigenesis. Here, we review the major upstream mediators of gastrin gene regulation, including inflammation secondary to Helicobacter pylori infection and the use of PPIs. We further explore the molecular biology of gastrin in GI malignancies, with particular emphasis on the regulation of gastrin in neuroendocrine neoplasms. Finally, we highlight tissue-specific transcriptional targets as an avenue for targetable therapeutics. [ABSTRACT FROM AUTHOR]

Abstract Background Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant disorder arising from mutations of the MEN1 tumor suppressor gene on chromosome 11q13; MEN1 is characterized by the development of neuroendocrine tumors, including those of the parathyroid, gastrointestinal endocrine tissue and anterior pituitary. Additionally, thymic neuroendocrine tumors in MEN1 are also rarely reported. Case presentation This case report observed a family that presented with MEN1 p.L105Vfs mutation, and two of the family members had been diagnosed with thymic neuroendocrine tumor combined with MEN1. To the best of our knowledge, this is the first time such a mutation in the MEN1 gene has been reported. The proband presented with thymic neuroendocrine tumor, parathyroid adenoma and rectum adenocarcinoma. The son of the proband presented with thymic neuroendocrine tumor, gastrinoma, hypophysoma and parathyroid adenoma. Genetic testing revealed the frameshift mutation p.L105Vfs, leading to the identification of one carrier in the pedigree (the patient’s younger sister). The proband then underwent parathyroidectomy at the age of 26 years (in 1980) for a parathyroid adenoma. Subsequently, the patient underwent thymectomy, radiotherapy and chemotherapy. The patient is now 64 years old, still alive and still undergoing Lanreotide therapy. Conclusion Thymic neuroendocrine MEN1 is rare, but it accounts for almost 20% of MEN1-associated mortality. Consequently, we should focus on regular clinical screening of the thymus in MEN1 patients.

Acromegaly is a rare endocrine disorder characterized by the excessive production of growth hormone (GH) in adulthood. Currently, it is understood that certain pituitary neuroendocrine tumors (PitNETs) exhibit a hereditary predisposition. These tumors' genetic patterns fall into two categories: isolated and syndromic tumors. The isolated forms are characterized by molecular defects that predispose exclusively to PitNETs, including familial isolated pituitary adenomas (FIPAs) and sporadic genetic defects not characterized by hereditary predisposition. All the categories involve either germline or somatic mutations, or both, each associated with varying levels of penetrance and different phenotypes. This highlights the importance of genetic testing and the need for a more comprehensive view of the whole disease. Despite the availability of multiple treatment options, diagnosis often occurs after several years, and management is still difficult. Early detection and intervention are crucial for preventing complications and enhancing the quality of life for affected individuals. This review aims to elucidate the molecular, clinical, and histological characteristics of GH-secreting PitNETs, providing insights into their prevalence, treatment nuances, and the benefits of genetic testing for each type of genetic disorder associated with acromegaly.

Parathyroid carcinoma (PC) is extremely rare and is primarily treated surgically. Chemotherapy is an option for advanced stages, but no standard regimen exists. Emerging research suggests the efficacy of multitarget tyrosine kinase inhibitors (MTKIs) for PC, targeting vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR). A 61-year-old Japanese woman presented with a neck mass, diagnosed as PC with pleural and lumbar metastases. After parathyroidectomy and radiation for lumbar metastasis, immunohistochemistry showed VEGFR overexpression, leading to targeted therapy with MTKIs. Despite no actionable mutations on cancer genomic panel test, a novel MEN1 somatic mutation (NM&#95;130801: exon2: c.332delG: p.G111fs*8) was identified, which may affect VEGFR2 expression and tumor epigenetics. Although severe hand-foot syndrome necessitated dose reductions and treatment interruptions, sorafenib treatment managed hypercalcemia with evocalcet and denosumab. Lenvatinib, as second-line therapy, was effective against pleural metastases but caused thrombocytopenia and hematuria, leading to discontinuation and uncontrolled recurrence and metastasis progression. Our case highlights the need for further research on genomic profiling, molecular targets, and therapy response in PC., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)

Lipomatoses are benign proliferation of adipose tissue. Lipomas (benign fat tumors) are the most common component of lipomatosis. They may be unique or multiple, encapsulated or not, subcutaneous or sometimes visceral. In some cases, they form large areas of non-encapsulated fat hypertrophy, with a variable degree of fibrosis. They can develop despite the absence of obesity. They may be familial or acquired. At difference with lipodystrophy syndromes, they are not associated with lipoatrophy areas, except in some rare cases such as type 2 familial partial lipodystrophy syndromes (FPLD2). Their metabolic impact is variable in part depending on associated obesity. They may have functional or aesthetic consequences. Lipomatosis may be isolated, be part of a syndrome, or may be visceral. Isolated lipomatoses include multiple symmetrical lipomatosis (Madelung disease or Launois-Bensaude syndrome), familial multiple lipomatosis, the painful Dercum's disease also called Adiposis Dolorosa or Ander syndrome, mesosomatic lipomatosis also called Roch-Leri lipomatosis, familial angiolipomatosis, lipedema and hibernomas. Syndromic lipomatoses include PIK3CA-related disorders, Cowden/PTEN hamartomas-tumor syndrome, some lipodystrophy syndromes, and mitochondrial diseases, especially MERRF, multiple endocrine neoplasia type 1, neurofibromatosis type 1, Wilson disease, Pai or Haberland syndromes. Finally, visceral lipomatoses have been reported in numerous organs and sites: pancreatic, adrenal, abdominal, epidural, mediastinal, epicardial… The aim of this review is to present the main types of lipomatosis and their physiopathological component, when it is known., (Copyright © 2024 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Introduction: Multiple endocrine neoplasia type 1 (MEN1), an autosomal-dominantly inherited tumor syndrome, is classically defined by tumors arising from the "3 Ps": Parathyroids, Pituitary, and the endocrine Pancreas. The majority (>95%) of MEN1 patients will develop parathyroid tumors, 35% to 75% of patients will develop neuroendocrine tumors of the pancreas, <30% will have pituitary adenomas, and ... -- will develop other endocrine tumors such as adrenal adenomas and carcinomas. This case study seeks to emphasize the significance of accurately determining the underlying cause of basic signs such as hypoglycemia and conducting an in-depth examination of the patient to detect potential correlations between latent conditions. Case Report: This is the case of a 42-year-old female patient who presented at Akdeniz Hospital complaining of fatigue and hyperphagia. The patient's past medical history shows that she had surgical excision of an insulinoma in 2007 and had experienced weakness, fainting, and polyfagia over the previous three years. Blood testing showed low vitamin D levels, high calcium and PTH levels, and low glucose levels linked to high insulin and C-peptide levels. Computer tomography and parathyroid SPECT confirmed the results, which point to endocrine pancreas and parathyroid dysfunction. The patient was admitted for further investigations, including genetic testing for MEN1 syndrome. Discussions : Four smooth-bordered focal lesions were identified on the CT scan of the pancreatic tail section, the largest measuring 29x24 mm in size, compatible with Insulinoma. Additionally seen on the CT scan are bilateral nodular lesions on the adrenal glands, which raise the suspicion of pheochromocytoma. This led to the testing of catecholamine metabolites, which exhibited normal values for normetanephrine (37, 1 ug/24 h) and metanephrine (12, 7 ug/24 h). The Parathyroid SPECT detected lesions in the inferior commissure of both thyroid lobes, through an increased MIBI uptake in a hypo-isoechoic and heterogeneous area on the ultrasonography scan. A DEXA scan was conducted to assess bone density in the hip and lumbar spine due to the discovery of parathyroid dysfunction; both findings were conclusive for osteoporosis with a T-score of less than -2.5. Conclusions: The patient appears to have all the signs and symptoms of an uncommon case of MEN1 syndrome, which includes adrenal adenomas, pancreatic insulinoma, and parathyroid dysfunction. MEN1 is a complex disorder predisposing to more than 20 benign and malignant endocrine and nonendocrine neoplasms, still incompletely understood. [ABSTRACT FROM AUTHOR]

Multiple primary cancers, defined as three or more primary tumours, are rare, and there are few genetic studies concerning them. There is a need for increased knowledge on the heritability of multiple primary cancers and genotype-phenotype correlations. We have performed whole-genome/exome sequencing (WGS/WES) in ten individuals with three or more primary tumours, with no previous findings on standard clinical genetic investigations. In one individual with a clinical diagnosis of MEN1, a likely pathogenic cryptic splice site variant was detected in the MEN1 gene. The variant (c.654C > A) is synonymous but we showed in a cDNA analysis that it affects splicing and leads to a frameshift, with the theoretical new amino acid sequence p.(Gly219Glufs*13). In one individual with metachronous colorectal cancers, ovarian cancer, endometrial cancer and chronic lymphocytic leukaemia, we found a likely pathogenic variant in the MLH1 gene (c.27G > A), and two risk factor variants in the genes CHEK2 and HOXB13. The MLH1 variant is synonymous but has previously been shown to be associated to constitutional low-grade hypermethylation of the MLH1 promoter, and segregates with disease in families with colorectal and endometrial cancer. No pathogenic single nucleotide or structural variants were detected in the remaining eight individuals in the study. The pathogenic variants found by WGS/WES were in genes already sequenced by Sanger sequencing and WES in the clinic, without any findings. We conclude that, in individuals with an unequivocal clinical diagnosis of a specific hereditary cancer syndrome, where standard clinical testing failed to detect a causative variant, re-analysis may lead to a diagnosis. [ABSTRACT FROM AUTHOR]

Genomic analysis of Pancreatic Neuroendocrine Tumors (PanNETs) has revealed that these tumors often lack mutations in typical cancer-related genes such as the tumor suppressor gene p53. Instead, PanNET tumorigenesis usually involves mutations in specific PanNET-related genes, such as tumor suppressor gene MEN1. Using a PanNET mouse model, human tissues and human cell lines, we studied the cross-talk among MEN1, p53 and Notch signaling pathways and their role in PanNETs. Here, we show that reactivation of the early developmental program of islet cells underlies PanNET tumorigenesis by restoring the proliferative capacity of PanNET cells. We investigated the role of INSM1, a transcriptional regulator of islet cells' development, and revealed that its expression and subcellular localization is regulated by MEN1 and p53. Both human and mouse data show that loss of MEN1 in a p53 wild-type genetic background results in increased nuclear INSM1 expression and cell proliferation. Additionally, inhibition of Notch signaling in a p53 wild-type background reduces the proliferation of PanNET cells, due to repression of INSM1 transcription and nuclear localization. Our study elucidates the molecular mechanisms governing the interactions of INSM1 with MEN1, p53 and Notch and their roles in PanNET tumorigenesis, suggesting INSM1 as a key transcriptional regulator of PanNET cell proliferation. [ABSTRACT FROM AUTHOR]

Purpose: Lung neoplasms often co-occur with pituitary adenoma (PA). However, whether co-diagnosis of lung neuroendocrine tumors (LNETs) and PA constitute a unique entity and the impact of such co-diagnosis on patients' outcome is yet to be defined. The study objective was to compare patients' clinical characteristics with LNET to patients co-diagnosed with PA. Methods: A Retrospective, case-control study based on the Surveillance, Epidemiology, and End Results (SEER) registry database between 2000 and 2016. A total of 2947 patients with LNET, including 2913 with LNET alone ("Sporadic") and 34 patients with both LNET and PA ("LNET-PA"). Results: PA preceded LNET diagnosis in 85.3% of patients and had higher rates among LNET patients (34/2947) than with any cancer (p < 0.00001) and compared to patients with non-small cell lung cancer (NSCLC) (15/2378, p = 0.047). LNET-PA patients were younger at diagnosis compared with NSCLC patients and PA (p = 0.04). Among patients <60 years with LNET, co-diagnosis with PA was associated with lower all-cause mortality (ACM) risk (Log-rank test, p = 0.03). Adjusted ACM risk of patients with LNET-PA was lower than sporadic LNET (hazard ratio 0.553, 95% confidence interval 0.309–0.99, p = 0.046), especially among Caucasians, and lower overall-mortality risk in patients <60 years with borderline statistical significance (p = 0.071). Conclusions: Patients with both LNET and PA constitute a distinct morbidity and mortality profile than sporadic LNET, possibly suggesting an undefined MEN syndrome. Additional studies to further investigate patients' natural course and genetic profile with these neoplasms are needed. [ABSTRACT FROM AUTHOR]

Non-endocrine findings in patients with MEN1 (multiple endocrine neoplasia) syndrome also include skin lesions, especially tumor-type lesions. This is a narrative review of the English-language medical literature including original studies concerning MEN1 and dermatological issues (apart from dermatologic features of each endocrine tumor/neuroendocrine neoplasia), identified through a PubMed-based search (based on clinical relevance, with no timeline restriction or concern regarding the level of statistical significance). We identified 27 original studies involving clinical presentation of patients with MEN1 and cutaneous tumors; eight other original studies that also included the genetic background; and four additional original studies were included. The largest cohorts were from studies in Italy (N = 145 individuals), Spain (N = 90), the United States (N = 48 and N = 32), and Japan (N = 28). The age of patients varied from 18 to 76 years, with the majority of individuals in their forties. The most common cutaneous tumors are angiofibromas (AF), collagenomas (CG), and lipomas (L). Other lesions are atypical nevi, basocellular carcinoma, squamous cell carcinoma, acrochordons, papillomatosis confluens et reticularis, gingival papules, and cutaneous T-cell lymphoma of the eyelid. Non-tumor aspects are confetti-like hypopigmentation, café-au-lait macules, and gingival papules. MEN1 gene, respective menin involvement has also been found in melanomas, but the association with MEN1 remains debatable. Typically, cutaneous tumors (AF, CG, and L) are benign and are surgically treated only for cosmetic reasons. Some of them are reported as first presentation. Even though skin lesions are not pathognomonic, recognizing them plays an important role in early identification of MEN1 patients. Whether a subgroup of MEN1 subjects is prone to developing these types of cutaneous lesions and how they influence MEN1 evolution is still an open issue.

Background: Recent studies highlighted the increased frequency of AR-low or -negative prostate cancers (PCas) and the importance of AR-independent mechanisms in driving metastatic castration-resistant PCa (mCRPC) development and progression. Several previous studies have highlighted the involvement of the MEN1 gene in PCa. In the current study, we focused on its role specifically in AR-independent PCa cells. Methods: Cell tumorigenic features were evaluated by proliferation assay, foci formation, colony formation in soft agar, wound healing assay and xenograft experiments in mice. Quantitative RT-PCR, Western blot and immunostaining were performed to determine the expression of different factors in human PCa lines. Different ChIP-qPCR-based assays were carried out to dissect the action of JunD and β-catenin. Results: We found that MEN1 silencing in AR-independent cell lines, DU145 and PC3, resulted in an increase in anchorage independence and cell migration, accompanied by sustained MYC expression. By searching for factors known to positively regulate MYC expression and play a relevant role in PCa development and progression, we uncovered that MEN1-KD triggered the nuclear translocation of JunD and β-catenin. ChIP and 3C analyses further demonstrated that MEN1-KD led to, on the one hand, augmented binding of JunD to the MYC 5′ enhancer and increased formation of loop structure, and on the other hand, increased binding of β-catenin to the MYC promoter. Moreover, the expression of several molecular markers of EMT, including E-cadherin, BMI1, Twist1 and HIF-1α, was altered in MEN1-KD DU145 and PC3 cells. In addition, analyses using cultured cells and PC3-GFP xenografts in mice demonstrated that JunD and β-catenin are necessary for the altered tumorigenic potential triggered by MEN1 inactivation in AR-independent PCa cells. Finally, we observed a significant negative clinical correlation between MEN1 and CTNNB1 mRNA expression in primary PCa and mCRPC datasets. Conclusions: Our current work highlights an unrecognized oncosuppressive role for menin specifically in AR-independent PCa cells, through the activation of JunD and β-catenin pathways. [ABSTRACT FROM AUTHOR]

The availability of genomic sequencing for inherited diseases provides a more complete molecular basis for how an individual's genetic landscape influences clinical outcome. We describe a family where exome sequencing of a 3‐year‐old boy with clinical features of Cockayne syndrome (CS) confirmed the diagnosis of CS. He also had a mutation consistent with a pre‐symptomatic second disease, multiple endocrine neoplasia type 1 (MEN1), each potentially affecting multiple organ systems, in addition to a poorly defined variant in fumarate hydratase (FH). Genomic sequencing may reveal coexisting pathogenic mutations and variants which complicate clinical interpretation. [ABSTRACT FROM AUTHOR]

Abstract Background Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant inherited condition affecting multiple endocrine organs, resulting in significant morbidity and decreased life expectancy. Early tumor identification allows for timely patient management, reduces morbidity, and improves disease outcomes. Patients with MEN1 typically present with primary hyperparathyroidism caused by multiple parathyroid tumors, however, thymic and bronchial carcinoid tumors are also less common manifestations. MEN1-related neuroendocrine tumors often show hematogenous metastasis, with the liver being the most common metastatic site. Skeletal metastases from neuroendocrine tumors are extremely rare. As few as 50 case reports were identified in a recently published literature review on skeletal metastases from carcinoid tumors. To our knowledge, studies related to MEN1 have not been previously conducted. Case presentation We present a case of MEN1-related atypical ovarian carcinoid presenting as the first disease manifestation in a 30-year old woman. After two years, another atypical carcinoid was incidentally diagnosed in the contralateral ovary during a caesarean section. Syndromic MEN1 was not diagnosed clinically despite her young age and bilateral involvement. The patient remained disease-free for two years without further adjuvant treatment prior to clinic presentation with complaints of chest discomfort and body pain. Radiologic and pathologic investigations identified multifocal simultaneous neuroendocrine tumors involving the parathyroid, thymus, pancreas, and adrenal glands, in addition to multiple other metastatic sites. The findings ultimately resulted in the patient being diagnosed with MEN1. Conclusions This extremely rare case emphasizes that ovarian carcinoids, especially when bilateral, could be the initial manifestation of MEN1. The significance of this differential diagnosis was highlighted by the subsequent detection of widespread skeletal metastasis resulting from the carcinoid tumors. A low threshold of suspicion, systemic diagnostic work-up, and regular follow-up are of utmost importance to timely diagnosis of MEN1.

Abstract Background Pituitary adenoma and meningioma are the most common benign tumors in the central nervous system. Pituitary adenoma associated with meningioma (PAM) is a rare disease and the clinical features and mechanisms of PAM are unclear. Methods We summarized the clinical data of 57 PAM patients and compared with sporadic pituitary adenoma (SPA) and sporadic meningioma (SM). 5 pituitary adenomas of PAM and 5 SPAs were performed ceRNA microarray. qRT-PCR, Western Blot, siMEN1 and rapamycin inhibition experiment were validated for ceRNA microarray. Results Clinical variable analyses revealed that significant correlations between PAM and female sex as well as older age when compared with SPA and significant correlations between PAM and transitional meningioma as well as older age when compared with SM. Additionally, the characteristics of PAM were significantly different for MEN1 patients. Functional experiments showed lower expression of MEN1 can upregulate mTOR signaling, in accordance with the result of ceRNA microarray. Rapamycin treatment promotes apoptosis in primary pituitary adenoma and meningioma cells of PAM. Conclusions MEN1 plays an important role in PAM by upregulating mTOR signaling pathway. Rapamycin represents a potential therapeutic strategy for PAM in the future.

Background: Pituitary adenomas have a high disease burden due to tumor growth/ invasion and disordered hormonal secretion. Germline mutations in genes such as MEN1 and AIP are associated with early onset of aggressive pituitary adenomas that can be resistant to medical therapy. Aims: We performed a retrospective screening study using published risk criteria to assess the frequency of AIP and MEN1 mutations in pituitary adenoma patients in a tertiary referral center. Methods: Pituitary adenoma patients with pediatric/adolescent onset, macroadenomas occurring ≤30 years of age, familial isolated pituitary adenoma (FIPA) kin dreds and acromegaly or prolactinoma cases that were uncontrolled by medical therapy were studied genetically. We also assessed whether immunohistochemical staining for AIP (AIP-IHC) in somatotropinomas was associated with somatostatin analogs (SSA) response. Results: Fifty-five patients met the study criteria and underwent genetic screening for AIP/MEN1 mutations. No mutations were identified and large deletions/duplications were ruled out using MLPA. In a cohort of sporadic somatotropinomas, low AIP-IHC tumors were significantly larger (P = 0.002) and were more frequently sparsely granulated (P = 0.046) than high AIP-IHC tumors. No significant relationship between AIP-IHC and SSA responses was seen. Conclusions: Germline mutations in AIP/MEN1 in pituitary adenoma patients are rare and the use of general risk criteria did not identify cases in a large tertiary-referral setting. In acromegaly, low AIP-IHC was related to larger tumor size and more frequent sparsely granulated subtype but no relationship with SSA responsiveness was seen. The genetics of pituitary adenomas remains largely unexplained and AIP screening criteria could be significantly refined to focus on large, aggressive tumors in young patients.

Multiple endocrine neoplasia type 1 (MEN1) is an inherited disease caused by mutations in the MEN1 gene encoding a nuclear protein menin. Among those different endocrine tumors of MEN1, the pancreatic neuroendocrine tumors (PNETs) are life-threatening and frequently implicated. Since there are uncertainties in genotype and phenotype relationship and there are species differences between humans and mice, it is worth it to replenish the mice model with human cell resources. Here, we tested whether the patient-origin induced pluripotent stem cell (iPSC) lines could phenocopy some defects of MEN1. In vitro β-cell differentiation revealed that the percentage of insulin-positive cells and insulin secretion were increased by at least two-fold in MEN1-iPSC derived cells, which was mainly resulted from significantly higher proliferative activities in the pancreatic progenitor stage (Day 7–13). This scenario was paralleled with increased expressions of prohormone convertase1/3 (PC1/3), glucagon-like peptide-1 (GLP-1), GLP-1R, and factors in the phosphatidylinositol 3-kinase (PI3K)/AKT signal pathway, and the GLP-1R was mainly expressed in β-like cells. Blockages of either GLP-1R or PI3K significantly reduced the percentages of insulin-positive cells and hypersecretion of insulin in MEN1-derived cells. Furthermore, in transplantation of different stages of MEN1-derived cells into immune-deficient mice, only those β-like cells produced tumors that mimicked the features of the PNETs from the original patient. To the best of our knowledge, this was the first case using patient-origin iPSCs modeling most phenotypes of MEN1, and the results suggested that GLP-1R may be a potential therapeutic target for MEN1-related hyperinsulinemia.

Pancreatic neuroendocrine tumors (PNET) may develop sporadically or in the context of hereditary syndromes. In patients with multiple endocrine neoplasia type 1 (MEN1), PNET is the leading cause of death. Our aim was to compare the mortality risk in sporadic and MEN1-related PNETs and identify high-risk populations. A retrospective Surveillance, Epidemiology, and End Results database analysis of patients with PNET was used. Patients with MEN1 were defined by syn/metachronous pituitary adenoma. Clinical data were retrieved, and all-cause mortality (ACM) risk was compared in univariate and multivariable analyses. The cohort included 569 patients (46.6% males) with sporadic (n=542) and MEN1-related (n=27) PNETs. Age at diagnosis of MEN1-related PNET was significantly younger than with sporadic PNETs (mean age 49.2±16.7 vs. 61.6±12.7 years, respectively; p < 0.001). Survival analysis showed a trend for a better outcome in patients with MEN1-related vs. sporadic PNET (Log-rank, p=0.09) and in subgroup analysis for patients with advanced disease (p=0.08). Furthermore, among patients followed expectantly, those with MEN1-related PNET had lower ACM risk than their sporadic counterparts (p=0.08). Multivariable analysis demonstrated lower ACM risk in patients diagnosed with MEN1 (hazard ratio 0.35, 95% confidence interval 0.11–1.2, p=0.09), further supporting the trend detected in the univariate analysis. In conclusion, our study demonstrates the distinct clinical profile of patients with MEN1-related PNET compared to sporadic disease and emphasizes the expertise required to accurately manage patients with PNET in this rare context. The cautious decision-making required before embarking on surgical intervention is further emphasized in this robust analysis of a large cancer database. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objective: To report the clinical presentation, management and outcomes of young patients with prolactinomas (<20 years) and conduct a systematic review and meta‐analysis. Patients and Design: Clinical, biochemical and radiological data (1996‐2018) were collected from our centre. A systematic review and meta‐analysis of published literature (1994‐2019) on prolactinoma (age <20 years) were conducted. Both random and fixed effects meta‐analysis were used to pool outcomes across studies. Results 1 Case series: Twenty‐two patients (14 females) were identified; median age at diagnosis 15.7 years (range 13‐19); 12 patients (6 females) had a macroprolactinoma. Seven patients (macroprolactinoma‐6) had associated pituitary hormone deficiencies at presentation. Five patients (4 males) underwent surgical resection due to poor response to cabergoline or apoplexy. Patients undergoing surgery had larger tumours (p <.02) and higher serum prolactin concentration (p <.005). All patients with macroprolactinoma >20 mm required surgical intervention. Results 2 Systematic review and meta‐analysis: We selected 11 studies according to strict inclusion criteria describing 275 patients. Macroprolactinoma was more common in girls (78.7% [95% CI 70.5‐85.9]) than boys and was more frequent than microprolactinoma (56.6% [95% CI 48.4‐64.5]). In males, only 6/57 (10.5%) of tumours were microprolactinoma as compared to 102/198 (51.5%) microprolactinoma in females (risk difference −0.460; [95% CI −0.563 to −0.357]; p <.001). Surgery was first‐line therapy in 18.9% patients, with another 15.4% requiring it as a second line (overall 31.3%). Conclusions: Macroprolactinoma, particularly if >20 mm, usually requires multimodal therapy including surgical intervention. While overall prolactinomas in <20 years age group are more common in females, the proportion of macroprolactinoma vs microprolactinoma is greater in males, particularly for large invasive tumours. Microprolactinoma is a rare diagnosis in adolescent males. [ABSTRACT FROM AUTHOR]

Thoracic (pulmonary and thymic) neuroendocrine tumors are well-differentiated epithelial neuroendocrine neoplasms that are classified into typical and atypical carcinoid tumors based on mitotic index cut offs and presence or absence of necrosis. This classification scheme is of great prognostic value but designed for surgical specimens, only. Deep molecular characterization of thoracic neuroendocrine tumors highlighted their difference with neuroendocrine carcinomas. Neuroendocrine tumors of the lung are characterized by a low mutational burden, and a high prevalence of mutations in chromatin remodeling and histone modification-related genes, whereas mutations in genes frequently altered in neuroendocrine carcinomas are rare. Molecular profiling divided thymic neuroendocrine tumors into three clusters with distinct clinical outcomes and characterized by a different average of copy number instability. Moreover, integrated histopathological, molecular and clinical evidence supports the existence of a grey zone category between neuroendocrine tumors (carcinoid tumors) and neuroendocrine carcinomas. Indeed, cases with well differentiated morphology but mitotic/Ki-67 indexes close to neuroendocrine carcinomas have been increasingly recognized. These are characterized by specific molecular profiles and have an aggressive clinical behavior. Finally, thoracic neuroendocrine tumors may arise in the background of genetic susceptibility, being MEN1 syndrome the well-defined familial form. However, pathologists should be aware of rarer germline variants that are associated with the concurrence of neuroendocrine tumors of the lung or their precursors (such as DIPNECH) with other neoplasms, including but not limited to breast carcinomas. Therefore, genetic counseling for all young patients with thoracic neuroendocrine neoplasia and/or any patient with pathological evidence of neuroendocrine cell hyperplasia-to-neoplasia progression sequence or multifocal disease should be considered. [ABSTRACT FROM AUTHOR]

Regulation of the serum calcium level in humans is achieved by the endocrine action of parathyroid glands working in concert with vitamin D and a set of critical target cells and tissues including osteoblasts, osteoclasts, the renal tubules, and the small intestine. The parathyroid glands, small highly vascularized endocrine organs located behind the thyroid gland, secrete parathyroid hormone (PTH) into the systemic circulation as is needed to keep the serum free calcium concentration within a tight physiologic range. Primary hyperparathyroidism (HPT), a disorder of mineral metabolism usually associated with abnormally elevated serum calcium, results from the uncontrolled release of PTH from one or several abnormal parathyroid glands. Although in the vast majority of cases HPT is a sporadic disease, it can also present as a manifestation of a familial syndrome. Many benign and malignant sporadic parathyroid neoplasms are caused by loss-of-function mutations in tumor suppressor genes that were initially identified by the study of genomic DNA from patients who developed HPT as a manifestation of an inherited syndrome. Somatic and inherited mutations in certain proto-oncogenes can also result in the development of parathyroid tumors. The clinical and genetic investigation of familial HPT in kindreds found to lack germline variants in the already known HPT-predisposition genes represents a promising future direction for the discovery of novel genes relevant to parathyroid tumor development.

Background: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited syndrome that concurrently involves various endocrine glands. We report a rare case of MEN1 in a 43-year-old man whose first manifestation was an asymptomatic mediastinal mass. Case presentation: A 13-cm-sized mediastinal mass was diagnosed as an atypical thymic carcinoid by computed tomography and percutaneous needle biopsy. In addition, hypercalcemia from a left inferior parathyroid hyperplasia, and a non-functioning gastric neuroendocrine tumor seen on esophagogastroduodenoscopy were found. Therefore, the patient was clinically diagnosed with MEN1 syndrome, and underwent surgical resection of thymic carcinoid tumor after pre-operative concurrent chemoradiation therapy to decrease tumor size and volume. Parathyroid lesion and gastric neuroendocrine tumor were also removed. Finally, a MEN1 gene mutation was observed in the patient and his 7-year-old son. Conclusion: Despite its rare occurrence, thymic carcinoid tumor should be considered as a MEN1-associated tumor and necessitates screening of other endocrine glands. Thymic carcinoid tumor carries a poor prognosis in patients with MEN1, and thus it needs to be carefully monitored even after radical excision. [ABSTRACT FROM AUTHOR]

Regulation of the serum calcium level in humans is achieved by the endocrine action of parathyroid glands working in concert with vitamin D and a set of critical target cells and tissues including osteoblasts, osteoclasts, the renal tubules, and the small intestine. The parathyroid glands, small highly vascularized endocrine organs located behind the thyroid gland, secrete parathyroid hormone (PTH) into the systemic circulation as is needed to keep the serum free calcium concentration within a tight physiologic range. Primary hyperparathyroidism (HPT), a disorder of mineral metabolism usually associated with abnormally elevated serum calcium, results from the uncontrolled release of PTH from one or several abnormal parathyroid glands. Although in the vast majority of cases HPT is a sporadic disease, it can also present as a manifestation of a familial syndrome. Many benign and malignant sporadic parathyroid neoplasms are caused by loss-of-function mutations in tumor suppressor genes that were initially identified by the study of genomic DNA from patients who developed HPT as a manifestation of an inherited syndrome. Somatic and inherited mutations in certain proto-oncogenes can also result in the development of parathyroid tumors. The clinical and genetic investigation of familial HPT in kindreds found to lack germline variants in the already known HPT-predisposition genes represents a promising future direction for the discovery of novel genes relevant to parathyroid tumor development. [ABSTRACT FROM AUTHOR]

Pancreatic neuroendocrine neoplasms (panNENs) are the second most common epithelial tumors of the pancreas. Despite improvements in prognostic grading and staging systems, it remains a challenge to predict the clinical behavior of panNENs and the response to specific therapies given the high degree of heterogeneity of these tumors. Most panNENs are nonfunctional and present as advanced disease. However, systemic therapies provide modest benefits. Therefore, there is a need for predictive biomarkers to develop personalized treatment and to advance new drug development. The somatostatin receptors remain the only clinically established prognostic and predictive biomarkers in panNENs. Oncogenic drivers are at a very low frequency. Commonly mutated genes in panNENs include MEN1, chromatin remodeling genes (DAXX and ATRX), and mammalian target of rapamycin pathway genes. In contrast, poorly differentiated neuroendocrine carcinomas (panNECs), which carry a very poor prognosis, have distinctive mutations in certain genes (eg, RB1 and p53). Ongoing research to integrate epigenomics will provide tremendous opportunities to improve current understanding of the clinical heterogeneity of pancreatic neuroendocrine tumors and provide invaluable insight into the biology of these tumors, new drug development, and establishing personalized therapies. A wider application of new technologies that will go beyond simple genetic markers and would include epigenetic data will ensure that pancreatic neuroendocrine neoplasms will be managed best by molecularly tailored therapies that are currently not a standard of care. [ABSTRACT FROM AUTHOR]

Multiple endocrine neoplasia type 1 (MEN1) is a rare syndrome caused by inactivating mutations in the MEN1 tumor suppressor gene. The three main clinical manifestations of MEN1 are primary hyperparathyroidism (PHPT), duodenal-pancreatic neuroendocrine tumors (DP-NETs) and anterior pituitary tumors. Endocrine tumors in patients with MEN1 differ from sporadic tumors because of their younger age at onset, common multiple presentations and the different clinical course. MEN1 is characterized by a complex clinical phenotype; thus, patients should be followed by a multidisciplinary team of experts that includes an endocrinologist, a surgeon, a oncologist, a radiotherapist, and not least, a nutritionist. It is important to remember the fundamental role that diet plays as a primary prevention tool, together with a healthy and active lifestyle in preventing osteoporosis/osteopenia and reducing the risk of developing kidney stones due to hypercalciuria, two frequent clinical complications in MEN1 patients. Is very important for MEN1 patients to have an adequate intake of calcium, vitamin D, magnesium and phosphate to maintain good bone health. The intake of foods containing oxalates must also be kept under control because in combination with calcium they concur to form calcium oxalate crystals, increasing the risk of nephrolithiasis. Another aspect to consider is the management of patients with pancreatic neuroendocrine tumors undergoing major surgical resections of the pancreas that can lead to alterations in digestion and absorption mechanisms due to partial or total reduction in pancreatic enzymes such as amylase, lipase, and protease, resulting in malabsorption and malnutrition. Therefore, the nutritionist's aim should be to devise a dietary plan that takes into consideration each single patient, educating them about a healthy and active lifestyle, and accompanying them through various life stages by implementing strategies that can enhance their quality of life.

Primary hyperparathyroidism with parathyroid tumors is a typical manifestation of Multiple Endocrine Neoplasia Type 1 (MEN1) and is historically termed "primary hyperplasia". Whether these tumors represent a multi-glandular clonal disease or hyperplasia has not been robustly proven so far. Loss of Menin protein expression is associated with inactivation of both alleles and a good surrogate for a MEN1 gene mutation. The cyclin-dependent kinase inhibitor 1B (CDKN1B) gene is mutated in MEN4 and encodes for protein p27 whose expression is poorly studied in the syndromic MEN1 setting.Here, we analyzed histomorphology and protein expression of Menin and p27 in parathyroid adenomas of 25 patients of two independent, well-characterized MEN1 cohorts. The pattern of loss of heterozygosity (LOH) was assessed by fluorescence in situ hybridization (FISH) in one MEN1-associated parathyroid adenoma. Further, next-generation sequencing (NGS) was performed on eleven nodules of four MEN1 patients.Morphologically, the majority of MEN1 adenomas consisted of multiple distinct nodules, in which Menin expression was mostly lost and p27 protein expression reduced. FISH analysis revealed that most nodules exhibited MEN1 loss, with or without the loss of centromere 11. NGS demonstrated both subclonal evolution and the existence of clonally unrelated tumors.Syndromic MEN1 parathyroid adenomas therefore consist of multiple clones with subclones, which supports the current concept of the novel WHO classification of parathyroid tumors (2022). p27 expression was lost in a large fraction of MEN1 parathyroids and must therefore be used with caution in suggesting MEN4., (© 2024. The Author(s).)

Multiple gastroenteric, pancreatic, and pituitary neuroendocrine neoplasms (NENs) were diagnosed in a 74-year-old man with a history of primary hyperparathyroidism (PHPT). Germline testing demonstrated a variant of MEN1 (c.1694T>A, p.L565Q), whose pathogenicity was classified as a variant of uncertain significance (VUS) according to the ACMG/AMP guidelines. The same germline variant was detected in the patient's son and daughter, who also showed PHPT or hypercalcemia and met the clinical diagnostic criteria for multiple endocrine neoplasia type 1 (MEN1). During surveillance of the son, multiple pancreatic tumors suggestive of NENs were detected. The pathogenicity of the current MEN1 variant was re-evaluated as likely pathogenic, based on additional family data.

Multiple endocrine neoplasia (MEN) is a group of syndromes with a genetic predisposition to the appearance of endocrine tumors, and shows autosomal dominant transmission. The advent of molecular genetics has led to improvements in the management of MEN in terms of diagnosis, prognosis and therapy. The genetics of MEN is the subject of regular updates, which will be presented throughout this paper. MEN1, the first to be described, is associated with the MEN1 gene. MEN1 is well known in terms of the observed phenotype, with genetic analysis being conclusive in 90% of patients with a typical phenotype, but is negative in around 10% of families with MEN1. Improvement in analysis techniques and the identification of other genes responsable for phenocopies allows the resolution of some, but not all, cases, notably non-familial forms suspected to be fortuitous assocations with tumors. MEN4 is a rare phenocopy of MEN1 linked to constitutional mutations in the CDKN1B gene. Though it closely resembles the phenotype of MEN1, published data suggests the appearance of tumors is later and less frequent in MEN4. MEN2, which results from mutations in the RET oncogene, shows a strong genotype-phenotype correlation. This correlation is particularly evident in the major manifestation of MEN2, medullary thyroid carcinoma (MTC), in which disease aggressiveness is dependent on the pathogenic variant of RET. However, recent studies cast doubt on this correlation between MTC and pathogenic variant. Lastly, the recent description of families carrying a mutation in MAX, which is known to predispose to the development of pheochromocytoma and paraganglioma, and presents a phenotypic spectrum that evokes MEN, suggests the existence of another syndrome, MEN5., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Targeted screening programs for individuals with an increased risk for cancer have become increasingly available. Patients with multiple endocrine neoplasia (MEN), rare genetic conditions associated with the development of tumors in the endocrine glands, undergo intensive surveillance from an early age. Quantitative research has shown that patients with MEN experience fear of disease occurrence in themselves and their family members. However, little is known about the role that intensive, lifelong screening plays in the lives of individuals. This study investigates the lived experiences of patients with MEN undergoing regular tumor screening through an interpretative phenomenological analysis of interviews with 12 patients with MEN1, MEN2A, or MEN2B syndrome. Four experiential group themes are identified: coming to the foreground/fading into the background, relating to uncertainty, experiencing control, and familial context. Screening is characterized as an ambiguous experience that brings MEN to the foreground and may both exacerbate MEN-related uncertainty as well as provide a sense of control over the disease. The experience of undergoing screening is strongly influenced by the familial context, as participants care for and are cared for by family members and understand their disease through familial experiences. Good care according to patients with MEN includes providing family-centered care, addressing the impact on daily functioning and the meaning of illness, support in the interpretation of physical complaints, facilitation of patient experiences of control, and careful attunement to patient needs within a good doctor-patient relationship., (© 2023 The Authors. Journal of Genetic Counseling published by Wiley Periodicals LLC on behalf of National Society of Genetic Counselors.)