Case report: Comprehensive follow-up of a Colombian family carrying a novel MEN1 variant linked to a rare ACTH-producing pancreatic neuroendocrine carcinoma.

Background: Multiple Endocrine Neoplasia type 1 (MEN1) is an autosomal dominant disorder marked by pathogenic variants in the MEN1 tumor suppressor gene, leading to tumors in the parathyroid glands, pancreas, and pituitary. The occurrence of ACTH-producing pancreatic neuroendocrine carcinoma is exceedingly rare in MEN1. Case presentation: This report details a Colombian family harboring a novel MEN1 variant identified through genetic screening initiated by the index case. Affected family members exhibited primary hyperparathyroidism (PHPT) symptoms from their 20s to 50s. Uniquely, the index case developed an ACTH-secreting pancreatic neuroendocrine carcinoma, a rarity in MEN1 syndromes. Proactive screening enabled the early detection of pituitary neuroendocrine tumors (PitNETs) as microadenomas in two carriers, with subsequent surgical or pharmacological intervention based on the clinical presentation. Conclusion: Our findings underscore the significance of cascade screening in facilitating the early diagnosis and individualized treatment of MEN1, contributing to better patient outcomes. Additionally, this study brings to light a novel presentation of ACTH-producing pancreatic neuroendocrine carcinoma within the MEN1 spectrum, expanding our understanding of the disease's manifestations.

Sweet Saboteur: Insulinoma Presenting As Recurrent Hypoglycemic Seizures.

Insulinoma, a rare neuroendocrine tumor of the pancreas, often presents diagnostic challenges due to its diverse clinical manifestations. We present the case of a 25-year-old female with recurrent hypoglycemic seizures and neuroglycopenic symptoms, ultimately diagnosed with insulinoma. Despite an initial asymptomatic period, the patient experienced progressively worsening symptoms over three years, culminating in eight episodes of generalized tonic-clonic seizures per week. Biochemical investigations during hypoglycemic episodes revealed elevated C-peptide and insulin levels, consistent with endogenous hyperinsulinemia. Imaging studies, including contrast-enhanced computed tomography (CECT) and Ga-DOTATATE scan, confirmed a hyper-enhancing lesion in the distal body of the pancreas, indicative of insulinoma. Histopathological examination (HPE) further corroborated the diagnosis. Prompt recognition and surgical excision led to the complete resolution of symptoms and improved long-term prognosis. This case underscores the importance of considering insulinoma in young individuals presenting with recurrent hypoglycemic episodes and highlights the significance of early diagnosis and intervention in preventing morbidity and mortality associated with this condition.

Menin signaling and therapeutic targeting in breast cancer.

To date, mounting evidence have shown that patients with multiple endocrine neoplasia type 1 (MEN1) may face an increased risk for breast carcinogenesis. The product of the MEN1 gene, menin, was also indicated to be an important regulator in breast cancer signaling network. Menin directly interacts with MLL, EZH2, JunD, NF-κB, PPARγ, VDR, Smad3, ß-catenin and ERα to modulate gene transcriptions leading to cell proliferation inhibition. Moreover, interaction of menin-FANCD2 contributes to the enhancement of BRCA1-mediated DNA repair mechanism. Ectopic expression of menin causes Bax-, Bak- and Caspase-8-dependent apoptosis. However, despite numbers of menin inhibitors were exploited in other cancers, data on the usage of menin inhibitors in breast cancer treatment remain limited. In this review, we focused on the menin associated signaling pathways and gene transcription regulations, with the aim of elucidating its molecular mechanisms and of guiding the development of novel menin targeted drugs in breast cancer therapy.

Role of Nutrition in the Management of Patients with Multiple Endocrine Neoplasia Type 1.

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.

Whole-Exome Screening and Analysis of Signaling Pathways in Multiple Endocrine Neoplasia Type 1 Patients with Different Outcomes: Insights into Cellular Mechanisms and Possible Functional Implications.

Multiple endocrine neoplasia type 1 (MEN1) is a syndrome characterized by tumors in multiple organs. Although being a dominantly inherited monogenic disease, disease phenotypes are unpredictable and differ even among members of the same family. There is growing evidence for the role of modifier genes in the alteration of the course of this disease. However, genome-wide screening data are still lacking. In our study, we addressed the different outcomes of the disease, focusing on pituitary and adrenocortical tumors. By means of exome sequencing we identified the affected signaling pathways that segregated with those symptoms. Most significantly, we identified damaging alterations in numerous structural genes responsible for cell adhesion and migration. Additionally, in the case of pituitary tumors, genes related to neuronal function, survival, and morphogenesis were repeatedly identified, while in patients with adrenocortical tumors, TLR10, which is involved in the regulation of the innate immunity, was commonly modified. Our data show that using exome screening, it is possible to find signatures which correlate with the given clinical MEN1 outcomes, providing evidence that studies addressing modifier effects in MEN1 are reasonable.

Insulinoma Presenting With Postprandial Hypoglycemia in a Pregnant Woman With MEN-1.

Insulinomas are rare insulin-secreting tumors of pancreatic origin that cause hypoglycemia and can be associated with multiple endocrine neoplasia type 1 (MEN1). While rare, they are the most common cause of hypoglycemia related to endogenous hyperinsulinism. A 28-year-old woman with known MEN1 presented with postprandial hypoglycemia in the second trimester of pregnancy. Prior to her presentation she was known to have several pancreatic neuroendocrine tumors that had been stable on serial imaging, but no history of hypoglycemia. She was managed with dietary intervention during pregnancy and gave birth to a healthy baby at 37 weeks' gestation. After pregnancy, hypoglycemia initially resolved, but then recurred at 8 months post partum. Magnetic resonance imaging showed several pancreatic neoplasms with the largest lesion measuring 29 mm in the pancreatic tail, unchanged from previous imaging. After localization with a selective arterial calcium stimulation test, the patient underwent successful distal pancreatectomy with resolution of symptoms. This case is unusual in that her initial presentation was during pregnancy, she had predominantly postprandial rather than fasting hypoglycemia, and her symptoms remitted for several months after delivery. Key learning points are to have a low index of suspicion for an insulinoma when there is a history of MEN1 and the need for a pragmatic approach to diagnosis and treatment during pregnancy.

A Novel Pathogenic MEN1 Gene Variant Identified in a Family With Multiple Pancreatic Neuroendocrine Tumors.

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary endocrine tumor syndrome caused by pathogenic variants in the MEN1 gene, and most patients with this syndrome initially develop primary hyperparathyroidism (PHPT). Here, we report the case of a family wherein a germline MEN1 variant was detected and multiple pancreatic neuroendocrine tumors (PanNETs) were observed at the initial evaluation. A 40-year-old woman presented with a complaint of abdominal discomfort, and a close examination revealed multiple pancreatic tumors. Distal pancreatectomy with splenectomy was performed, and the diagnosis was nonfunctional PanNETs. Five years later, her 76-year-old mother was referred to the hospital with multiple pancreatic tumors. A genetic test revealed that both patients harbored a previously unreported germline variant in the MEN1 gene. Although it was classified as a variant of uncertain significance, we suspect that it may be associated with the pathogenesis of these lesions. This case report presents a new disease concept-familial isolated pancreatic neuroendocrine tumors, or FIPNETs-in patients harboring a pathogenic variant in the MEN1 gene who experience only pancreatic lesions. We suggest that clinicians consider genetic testing for the MEN1 gene in patients with multiple pancreatic lesions who show no signs of PHPT.

Coincidental Occurrence of Multiple Endocrine Neoplasia Type 1 and Breast Cancer in a Young Saudi Girl: A Case Study and Genetic Analysis.

Multiple Endocrine Neoplasia Type 1 (MEN-1) is an autosomal dominant familial disorder associated with tumors in both endocrine and non-endocrine organs. It is uncommon for MEN-1 to coincide with breast cancer. We present a case of a 15-year-old Saudi girl who exhibited the classic symptoms of MEN-1 and subsequently developed breast cancer. The patient's breast cancer was diagnosed using ultrasonography and core biopsy, and she was treated with surgical interventions. Despite these treatments, her cancer progressed to a metastatic stage, and her overall health deteriorated, leading to cardiopulmonary arrest at a young age. Although the simultaneous appearance of MEN-1 and breast cancer in our patient may suggest a potential link, our comprehensive genetic analysis found no relationship between her MEN-1 mutation and the onset of breast cancer. This suggests that, in this case, the two conditions co-occurred by chance. Nonetheless, additional research is needed to explore potential associations between MEN-1 and breast cancer.

Pancreatic Neuroendocrine Tumors in MEN1 Patients: Difference in Post-Operative Complications and Tumor Progression between Major and Minimal Pancreatic Surgeries.

Pancreatic neuroendocrine neoplasms (PNENs) affect over 80% of patients with multiple endocrine neoplasia type 1 (MEN1). Surgery is usually the therapy of choice, but the real immediate and long-term therapeutic benefit of a partial extensive pancreatic resection remains controversial. We analyzed, in 43 PNEN MEN1 patients who underwent 19 pancreaticoduodenectomies (PD), 19 distal pancreatectomies (DP), and 5 minimal pancreatectomies, the prevalence of surgery-derived early complications and post-operative pancreatic sequelae, and the PNEN relapse-free survival time after surgery, comparing major (PD+DP) and minimal pancreatic surgeries. No post-operative mortality was observed. Metastatic cancers were found in 12 cases, prevalently from duodenal gastrinoma. Long-term cure of endocrine syndromes, by the 38 major pancreatic resections, was obtained in 78.9% of gastrinomas and 92.9% of insulinomas. In only one patient, hepatic metastases, due to gastrinoma, progressed to death. Out of the 38 major surgeries, only one patient was reoperated for the growth of a new PNEN in the remnant pancreas. No functioning PNEN persistence was reported in the five minimal pancreatic surgeries, PNEN relapse occurred in 60% of patients, and 40% of cases needed further pancreatic resection for tumor recurrence. No significant difference in PNEN relapse-free survival time after surgery was found between major and minimal pancreatic surgeries.

Relevance of Endoscopic Ultrasound in Endocrinology Today: Multiple Endocrine Neoplasia Type 1, Insulinoma, Primary Aldosteronism-An Expert's Perspective Based on Three Decades of Scientific and Clinical Experience.

In endocrinology, endoscopic ultrasound (EUS) may be used to image the adrenals, the endocrine pancreas, and other organs where endocrine neoplasms may occur. During the recent decades, EUS has been established predominantly to assess multiple endocrine neoplasia type 1, to localize insulinomas, and to identify aldosterone-producing adenomas. EUS in endocrinology requires special skills and individual experience in order to provide reliable diagnostic information.

Precision radiotherapy using MR-linac for pancreatic neuroendocrine tumors in MEN1 patients (PRIME): a protocol for a phase I-II trial, and systematic review on available evidence for radiotherapy of pNETs.

Background: Surgical resection is the standard of care for the treatment of pancreatic neuro-endocrine tumors (pNETs) in patients with Multiple Endocrine Neoplasia Type 1 (MEN1). However, surgery can cause significant short- and long-term morbidity. Magnetic resonance-guided radiotherapy (MRgRT) is a potential effective treatment with little side effects. With traditional radiotherapy techniques, irradiation of pancreatic tumors to high dose levels was hampered by poor visibility of the tumor during treatment. MRgRT uses onboard MRI to guide the treatment, thereby enabling delivery of ablative irradiation doses to the tumor, while sparing surrounding tissues. In this study, we describe results from a systematic review assessing efficacy of radiotherapy in pNET and present the protocol of the PRIME study. Methods: PubMed, Embase and Cochrane Library were searched for articles assessing efficacy and side effects of radiotherapy for the treatment of pNETs. Risk of bias was assessed using the ROBINS-I Risk of Bias Tool for observational studies. Descriptive statistics were used to describe results of included trials. Results: Four studies comprising of 33 patients treated by conventional radiotherapy were included. Despite the heterogeneity of studies, radiotherapy appeared to be effective for the treatment of pNETs with most patients responding (45.5%) or stabilizing (42.4%) in tumor size. Conclusion and trial design: Due to the limited literature available and concerns about damage to surrounding tissue, conventional radiotherapy is currently little used for pNETs. The PRIME study is a phase I-II trial with a single arm prospective cohort study design, investigating the efficacy of MRgRT in MEN1 patients with pNET. MEN1 patients with growing pNETs with a size between 1.0 and 3.0 cm without malignant features are eligible for inclusion. Patients are treated with 40 Gy in 5 fractions on the pNET, using online adaptive MRgRT on a 1.5T MR-linac. The primary endpoint is the change in tumor size at MRI 12 months follow-up. Secondary endpoints include radiotoxicity, quality of life, endocrine and exocrine pancreas function, resection rate, metastatic free and overall survival. When MRgRT is found effective with low radiotoxicity, it could reduce the need for surgery for pNET and preserve quality of life. Systematic Review Registration: PROSPERO https://clinicaltrials.gov/, (CRD42022325542).

Insulinoma in childhood: a retrospective review of 22 patients from one referral centre.

Background: Insulinomas are very rare in childhood with sparse knowledge on the clinical aspects and the presence of Multiple Endocrine Neoplasia type 1 (MEN1). Methods: We conducted a retrospective review of patients diagnosed with insulinoma between 1995 and 2021, presenting to one referral centre in Russia. Clinical, biochemical, genetic, imaging and histological data were collected. In addition, follow-up and family data were obtained. Results: A total of twenty-two children aged 5 to 16 years were identified. The median (range) gap between the first hypoglycaemia symptoms and diagnosis was 10 (1-46) months. Twelve children (55%) were misdiagnosed to have epilepsy and were treated with anticonvulsants before hypoglycemia was revealed. Contrast enhanced MRI and/or CT were accurate to localize the lesion in 82% (n=18). Five patients (23%) had multiple pancreatic lesions. All children underwent surgical treatment. The median (range) diameter of removed tumors was 1.5 (0.3-6) cm. Histopathological studies confirmed the presence of insulinoma in all cases. Immunohistochemical studies revealed G2 differentiation grade in 10 out of 17 cases. Two patients were diagnosed with metastatic insulinoma. One of them had metastases at the time of insulinoma diagnosis, while the other was diagnosed with liver metastases eight years after the surgery. Eight children (36%) were found to carry MEN1 mutations, inherited n=5, de novo n=1, no data, n=2. Children with MEN1 had significantly higher number of pancreatic tumors compared to sporadic cases. All of them developed additional MEN1 symptoms during the following 2-13 years. In the five patients with inherited MEN1, seven family members had hitherto undiscovered MEN1 manifestations. Conclusions: In this large cohort of children with rare pediatric insulinomas, MEN1 syndrome and G2 tumors were frequent, as well as hitherto undiscovered MEN1 manifestations in family members. Our data emphasize the need of genetic testing in all children with insulinoma and their relatives, even in the absence of any other features, as well as the importance of a prolonged follow-up observation.

MENIN-mediated regulation of gastrin gene expression and its role in gastrinoma development.

The Multiple Endocrine Neoplasia I (MEN1) locus encodes the protein MENIN, which functions as a tumor suppressor protein in neuroendocrine tissues. Gastrinomas are neuroendocrine neoplasms that overproduce the hormone gastrin and can arise sporadically or as part of the MEN1 syndrome, in which mutations in the MEN1 gene lead to loss or inactivation of MENIN protein. Gastrin is a peptide hormone that is primarily synthesized in the gastric antrum and stimulates the secretion of histamine from enterochromaffin-like (ECL) cells and subsequently acid from parietal cells in the gastric corpus. In addition, gastrin exerts a mitogenic function primarily on ECL cells and progenitor cells in the gastric isthmus. Current studies seek to understand how MEN1 mutations generate a mutant MENIN protein that abrogates its tumor suppressor function. Mutations in the MEN1 gene are broadly distributed throughout its nine protein-coding exons, making it difficult to correlate protein structure with its function. Although disruption of the Men1 locus in mice causes functional neuroendocrine tumors in the pituitary and pancreas, gastrinomas do not develop in these transgenic animal models. Prior studies of human gastrinomas suggest that tissue-specific microenvironmental cues in the submucosal foregut may contribute to tumorigenesis by reprogramming of epithelial cells toward the neuroendocrine phenotype. Accordingly, recent studies suggest that neural crest-derived cells are also sensitive to reprogramming when MEN1 is deleted or mutated. Thus, the goal of this report is to review our current understanding of how MENIN modulates gastrin gene expression while highlighting its role in the prevention/suppression of neuroendocrine cell transformation.

Metastatic Grade 3 Neuroendocrine Tumor in Multiple Endocrine Neoplasia Type 1 Expressing Somatostatin Receptors.

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) may occur in 30% to 90% of patients with multiple endocrine neoplasia type 1 (MEN1). However, only 1% of GEP-NETs are grade 3 (G3). Given the rarity of these aggressive tumors, treatment of advanced G3 GEP-NETs in MEN1 is based on the treatment guidelines for sporadic GEP-NETs. We report a 43-year-old male with germline MEN1 followed at our institution, with clinical features including hyperparathyroidism, a nonfunctional pancreatic NET, and Zollinger-Ellison syndrome. On routine surveillance imaging at age 40, computed tomography/positron emission tomography imaging showed 2 arterially enhancing intraluminal masses on the medial aspect of the gastric wall. Anatomical imaging confirmed 2 enhancing masses within the pancreas and a rounded mass-like thickening along the lesser curvature of the stomach. The gastric mass was resected, and pathology reported a well-differentiated G3 NET with a Ki-67 >20%. The patient continued active surveillance. Eighteen months later cross-sectional imaging studies showed findings consistent with metastatic disease within the right hepatic lobe and bland embolization was done. On follow-up scans, including 68Ga-DOTATATE (68Ga-DOTA(0)-Tyr(3)-octreotate) imaging, interval increase in number and avidity of metastatic lesions were compatible with disease progression. Given a paucity of treatment recommendations for G3 tumors in MEN1, the patient was counseled based on standard NET treatment guidelines and recommended 177Lu-DOTATATE treatment. PRRT (peptide receptor radionuclide therapy) with 177Lu-DOTATATE (177Lu-tetraazacyclododecanetetraacetic acid-octreotide) is an important therapeutic modality for patients with somatostatin receptor-positive NETs. However, prospective studies are needed to understand the role of PRRT in G3 NETs.

Zollinger Ellison Syndrome Refractory to Medical Therapy in the Setting of Multiple Endocrine Neoplasia Type I.

Multiple Endocrine Neoplasia 1 (MEN1) syndrome is a genetic condition arising from a mutation of the MEN1 gene resulting in neuroendocrine tumor formation. Patients with MEN1 are at a higher risk of developing Zollinger-Ellison syndrome (ZES) due to the growth of neuroendocrine tumors called gastrinomas that release gastrin leading to hypersecretion of acid in the stomach resulting in severe ulcerative disease of the upper GI tract. Our case is a 42-year-old female with newly diagnosed MEN1 syndrome, presenting with acute abdominal pain and dyspepsia refractory to medical management including proton pump inhibitors (PPI) and H2 antagonists. ZES was biochemically confirmed with a secretin stimulation test and dotatate positron emission tomography/computed tomography (PET/CT) revealed multiple areas of hyper-metabolic activity within the gastrinoma triangle. However, no discrete masses could be appreciated on endoscopic ultrasound (EUS) or CT imaging that could provide a target for surgical intervention. This case elucidates not only the difficulty of gastrinoma localization in medically refractory ZES but also reinforces the need to screen patients with MEN1 presenting with acute abdominal pain and dyspepsia for ZES.

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).

Investigating the Effects of Amino Acid Variations in Human Menin.

Human menin is a nuclear protein that participates in many cellular processes, as transcriptional regulation, DNA damage repair, cell signaling, cell division, proliferation, and migration, by interacting with many other proteins. Mutations of the gene encoding menin cause multiple endocrine neoplasia type 1 (MEN1), a rare autosomal dominant disorder associated with tumors of the endocrine glands. In order to characterize the structural and functional effects at protein level of the hundreds of missense variations, we investigated by computational methods the wild-type menin and more than 200 variants, predicting the amino acid variations that change secondary structure, solvent accessibility, salt-bridge and H-bond interactions, protein thermostability, and altering the capability to bind known protein interactors. The structural analyses are freely accessible online by means of a web interface that integrates also a 3D visualization of the structure of the wild-type and variant proteins. The results of the study offer insight into the effects of the amino acid variations in view of a more complete understanding of their pathological role.

Bone phenotypes in multiple endocrine neoplasia type 1: survey on the MEN1 Florentine database.

Multiple endocrine neoplasia type 1 (MEN1) is a rare, inherited cancer syndrome characterized by the development of multiple endocrine and non-endocrine tumors. MEN1 patients show a reduction of bone mass and a higher prevalence of early onset osteoporosis, compared to healthy population of the same age, gender, and ethnicity. During the monitoring and follow-up of MEN1 patients, the attention of clinicians is primarily focused on the diagnosis and therapy of tumors, while the assessment of bone health and mineral metabolism is, in many cases, marginally considered. In this study, we retrospectively analyzed bone and mineral metabolism features in a series of MEN1 patients from the MEN1 Florentine database. Biochemical markers of bone and mineral metabolism and densitometric parameters of bone mass were retrieved from the database and were analyzed based on age ranges and genders of patients and presence/absence of the three main MEN1-related endocrine tumor types. Our evaluation confirmed that patients with a MEN1 diagnosis have a high prevalence of earlyonset osteopenia and osteoporosis, in association with levels of serum and urinary markers of bone turnover higher than the normal reference values, regardless of their different MEN1 tumors. Fifty percent of patients younger than 26 years manifested osteopenia and 8.3% had osteoporosis, in at least one of the measured bone sites. These data suggest the importance of including biochemical and instrumental monitoring of bone metabolism and bone mass in the routine medical evaluation and follow-up of MEN1 patients and MEN1 carriers as important clinical aspects in the management of the syndrome.

[Comparison of clinical characteristics between sporadic gastrinoma and multiple endocrine neoplasia type 1-related gastrinoma].

Objective: To compare clinical characteristics of sporadic gastrinoma and multiple endocrine neoplasia type 1 (MEN1)-related gastrinoma. Methods: A retrospective cohort study was conducted. Patients with clinical manifestations of Zollinger-Ellison syndrome, pathological diagnosis as neuroendocrine neoplasm (NEN) and complete clinical and follow-up data were enrolled. Patients with only high gastric acid secretion but without evidence of NEN, or with other concurrent non-NEN tumors were excluded. According to the above criteria, the clinicopathological data of 52 cases of gastrinoma diagnosed from April 2003 to December 2020 in the First Affiliated Hospital, Sun Yat-sen University, were collected. Patients who met the diagnostic criteria of gastrinoma and met one of the following conditions were diagnosed as MEN1-related gastrinoma: (1) the presence of pathogenic mutations in the MEN1 gene confirmed by genetic testing; (2) NENs involving two or more endocrine glands, namely, pituitary, parathyroid, thymic, pancreatic, and adrenal NENs; (3) NEN and at least one first-degree relatives diagnosed as MEN1. The remaining gastrinomas were defined as sporadic gastrinoma. Student's t test and chi-square test were used for statistical analysis. Clinicopathological characteristics, endoscopic findings, imaging characteristics, treatment, and prognosis of sporadic and MEN1-related gastrinoma were compared. Results: Among 52 patients with gastrinoma, 33 were sporadic gastrinoma and 19 were MEN1-related gastrinoma. The common symptoms of both sporadic and MEN1-related gastrinomas were diarrhea (24/33, 72.7%; 17/19, 89.5%) and abdominal pain (19/33, 57.6%; 9/19, 47.4%). Compared with sporadic gastrinoma, MEN1-related gastrinoma needed longer time for diagnosis [(7.4±4.9) years vs. (3.9±5.2) years, t=-2.355, P=0.022), were more likely multiple tumors [47.4% (9/19) vs. 15.2% (5/33), χ(2)=6.361, P=0.012], had smaller diameter [(1.7±1.0) cm vs. (3.1±1.8) cm, t=2.942, P=0.005), presented the lower tumor grade [G1: 83.3% (15/18) vs. 39.4% (13/33); G2: 11.1% (2/18) vs. 54.5% (18/33); G3: 5.6% (1/18) vs. 6.1% (2/33), Z=-2.766, P=0.006], were less likely to have serum gastrin which was 10 times higher than normal [11.8% (2/17) vs. 56.0% (14/33), χ(2)=8.396, P=0.004], had higher probability of complication with type 2 gastric neuroendocrine tumors (g-NET) [31.6% (6/19) vs. 3.0%(1/33), χ(2)=6.163, P=0.013], and had lower rate of liver metastasis [21.1% (4/19) vs. 51.5% (17/33), χ(2)=4.648, P=0.031). There was no obvious difference between sporadic gastrinomas and MEN1-related gastrinomas in endoscopic findings. Both types presented enlarged and swollen gastric mucosa under the stimulation of high gastric acid, and multiple ulcers in the stomach and duodenum could be seen. Gastrinoma with type 2 g-NET presented multiple polypoid raised lesions in the fundus and body of the stomach. (68)Ga-SSR-PET/CT scan had a 100% detection rate for both types while (18)F-FDG-PET/CT scan had a higher detection rate for sporadic gastrinoma compared with MEN1-related gastrinoma [57.9% (11/19) vs. 20.0% (3/15), χ(2)=4.970, P=0.026]. Among the patients with sporadic gastrinoma, 19 received surgical treatment, 1 underwent endoscopic submucosal dissection, 8 underwent transcatheter arterial embolization (TAE), and 5 underwent surgery combined with TAE. Among patients with MEN1-related gastrinoma, 13 received surgical treatment, and the other 6 received conservative treatment. The median follow-up of all the patients was 21.5 (1-129) months, and the 5-year survival rate was 88.4%. The 5-year survival rate of patients with sporadic and MEN1-related gastrinomas was 89.5% and 80.0% respectively (P=0.949). The 5-year survival rate of patients with and without liver metastasis was 76.2% vs. 100%, respectively (P=0.061). Conclusions: Compared with sporadic gastrinoma, MEN1-related gastrinoma has longer diagnosis delay, smaller tumor diameter, lower tumor grading, lower risk of liver metastasis, and is more likely to complicate with type 2 g-NET, while there is no difference in survival between the two tumor types.

Well-Differentiated Bronchopulmonary Neuroendocrine Tumors: More Than One Entity.

INTRODUCTION: Until now, well-differentiated bronchopulmonary neuroendocrine tumors (bpNET) occurring either sporadically (sp-bpNET) or in the context of multiple endocrine neoplasia type 1 (MEN1) and diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) are regarded as similar entities. However, in contrast to sp-bpNET: MEN1-related and DIPNECH-related bpNET rarely metastasize or lead to bpNET-related death. We aimed to describe and compare the course of the disease of sp-bpNET, DIPNECH- and MEN1-related bpNET. METHODS: All patients with histologically confirmed MEN1-related bpNET from the DutchMEN Study Group database (1990-2017), patients with resected sp-bpNET and DIPNECH patients referred to a Dutch European Neuroendocrine Tumor Society center between 2000 and 2018 were included. Fisher's exact test was used for comparison between groups. The primary end point was disease-specific mortality (DSM). Kaplan-Meier and logrank test were used to compare survival. Cox regression was used to identify risk factors for DSM in the sp-bpNET subgroup. RESULTS: We included 112 sp-bpNET, 29 MEN1, and 27 DIPNECH patients. Tumor classification was similar across subgroups. A total of 20 patients (18%) with sp-bpNET died because of bpNET, compared with none in the MEN1 group and DIPNECH group. Median disease-specific survival was 12.3 (confidence interval: 6.3-18.3) years for patients with sp-bpNET, and not estimable for the other subgroups (p < 0.001). Differences in baseline characteristics did not explain worse survival in sp-bpNET. Tumor classification and age at diagnosis were independent risk factors for DSM in sp-bpNET. CONCLUSIONS: Patients with sp-bpNET have a significantly higher DSM compared with MEN1 or DIPNECH-related bpNET, unexplained by differences in baseline characteristics. This implies that not all bpNET are similar entities.