OBJECTIVE: This retrospective study evaluates the value of 68Ga-DOTATATE PET/CT in the diagnosis and localization of insulinomas, whether sporadic, malignant or MEN-1 associated insulinoma.
METHODS: The study included 43 patients, having clinical (symptomatic hypoglycemia) and/or laboratory suspicion of having insulinoma (72 h fasting test with serum insulin ≥18 pmol/L), with available pre-operative 68Ga-DOTATATE PET/CT and CE-CT, and diagnosed with insulinoma confirmed by post-operative histopathology. Preoperative imaging was retrospectively analyzed by two radiologists who were blinded to the final diagnosis and to the results of other imaging modalities. Histopathology of specimen was considered the reference standard, and head-to-head comparison of preoperative CE-CT and PET imaging findings. Findings were classified as true positive (TP), true negative (TN), false positive (FP), and false negative (FN) for each modality. Based on these results, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CE-CT, and 68Ga-DOTATATE PET/CT for the detection of insulinoma were calculated.
RESULTS: 43 patients (N = 43 patients, L = 56 lesions), out of these, 37 patients had benign sporadic insulinoma (N = 37, L = 42), only 3 patients had malignant sporadic insulinoma (N = 2, L = 9), and 3 patients had MEN-1 syndrome associated insulinoma (N = 3, L = 5). There was no significant statistical difference in sensitivity (P = 0.3058) and PPV (P = 0.5533) for insulinoma localization in the overall cohort with 68Ga-DOTATATE PET/CT (87.5 %, 90.74 %) compared to CE-CT (80.36 %, 93.75 %).
CONCLUSIONS: 68Ga-DOTATATE PET/CT is a non-invasive imaging modality that can identify most insulinomas. Still, it offers limited additional information when the tumor is localized by other anatomic imaging studies, so should be used as an adjunct when imaging studies fail to localize the tumor in insulinoma patients, especially when minimally invasive surgical is intended.

UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: 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.

BACKGROUND: Multiple endocrine neoplasias (MENs) are a group of hereditary diseases involving multiple endocrine glands, and their prevalence is low. MEN type 1 (MEN1) has diverse clinical manifestations, mainly involving the parathyroid glands, gastrointestinal tract, pancreas and pituitary gland, making it easy to miss the clinical diagnosis.
METHODS: We present the case of a patient in whom MEN1 was detected early. A middle-aged male with recurrent abdominal pain and diarrhea was admitted to the hospital. Blood tests at admission revealed hypercalcemia and hypophosphatemia, and emission computed tomography of the parathyroid glands revealed a hyperfunctioning parathyroid lesion. Gastroscopy findings suggested a duodenal bulge and ulceration. Ultrasound endoscopy revealed a hypoechoic lesion in the duodenal bulb. Further blood tests revealed elevated levels of serum gastrin. Surgery was performed, and pathological analysis of the surgical specimens revealed a parathyroid adenoma after parathyroidectomy and a neuroendocrine tumor after duodenal bulbectomy. The time from onset to the definitive diagnosis of MEN1 was only approximately 1 year.
CONCLUSIONS: For patients who present with gastrointestinal symptoms accompanied by hypercalcemia and hypophosphatemia, clinicians need to be alert to the possibility of MEN1.

Multiple endocrine neoplasia type 1 is a rare genetic neuroendocrine syndrome caused by over 1500 different germline mutations. It can cause 20 different endocrine tumors affecting primarily the parathyroid glands, gastroenteropancreatic tract, and the anterior pituitary gland. Multiple endocrine neoplasia type 2A (MEN2A) and Multiple endocrine neoplasia type 2B (MEN2B) are autosomal dominant genetic syndromes because of a germline variant in the \'rearranged during transfection\' (RET) proto-oncogene. There are common RET mutations causing receptor hyperactivation and induction of downstream signals that cause oncogenesis. Common conditions with MEN2A are medullary thyroid cancer (MTC), pheochromocytoma, and primary hyperparathyroidism. Common conditions with MEN2B include MTC, pheochromocytomas, and benign ganglioneuromas.

OBJECTIVE: Pancreatic neuroendocrine tumors (PNETs) are uncommon tumors which are increasing in incidence. The management of these tumors continues to evolve. This review examines the current role of surgery in the treatment of these tumors.
METHODS: Studies published over the past 10 years were identified using several databases including PubMed, MEDLINE, and Science Direct. Search terms included PNETs, treatment, and surgery. Clinical practice guidelines and updates from several major groups were reviewed.
RESULTS: Surgery continues to have a major role in the treatment of sporadic functional and nonfunctional PNETs. Pancreas-sparing approaches are increasingly accepted as alternatives to formal pancreatic resection in selected patients. Options such as watch and wait or endoscopic ablation may be reasonable alternatives to surgery for non-functional PNETs < 2 cm in size. Surgical decision-making in multiple endocrine neoplasia type 1 patients remains complex and in some situations such as gastrinoma quite controversial. The role of surgery has significantly diminished in patients with advanced disease due to the advent of more effective systemic and liver-directed therapies. However, the optimal treatments and sequencing in advanced disease remain poorly defined, and it has been suggested that surgery is underutilized in these patients.
CONCLUSIONS: Surgery remains a major treatment modality for PNETs. Given the plethora of available treatments, ongoing controversies and the changing landscape, management has become increasingly complex. An experienced multidisciplinary team which includes surgery is essential to manage these patients.

Duodenopancreatic neuroendocrine neoplasia (DP-NEN) is in approximately 10% of cases of multiple endocrine neoplasia type 1 (MEN1). We encountered a case in which the onset of NEN led to suspicion and diagnosis of MEN1. Although genetic testing showed MEN1 variant of uncertain significance (VUS), we considered it pathological from the clinical course, promoting the provision of genetic counseling and screening for relatives. MEN1 has a variety of clinical manifestations, and DP-NENs are the second-most common manifestation after primary hyperparathyroidism (pHPT). It is important to assume that MEN1 is an underlying cause of NEN.

We aimed to provide an in-depth analysis with respect to three turning points in pancreas involvement in primary hyperparathyroidism (PHP): hypercalcemia-induced pancreatitis (HCa-P), MEN1 (multiple endocrine neoplasia)-related neuroendocrine tumors (NETs), and insulin resistance (IR). This was a comprehensive review conducted via a PubMed search between January 2020 and January 2024. HCa-P (n = 9 studies, N = 1375) involved as a starting point parathyroid NETs (n = 7) or pancreatitis (n = 2, N = 167). Case report-focused analysis (N = 27) showed five cases of pregnancy PHP-HCa-P and three reports of parathyroid carcinoma (female/male ratio of 2/1, ages of 34 in women, men of 56). MEN1-NET studies (n = 7) included MEN1-related insulinomas (n = 2) or MEN1-associated PHP (n = 2) or analyses of genetic profile (n = 3), for a total of 877 MEN1 subjects. In MEN1 insulinomas (N = 77), the rate of associated PHP was 78%. Recurrence after parathyroidectomy (N = 585 with PHP) was higher after less-than-subtotal versus subtotal parathyroidectomy (68% versus 45%, p < 0.001); re-do surgery was 26% depending on surgery for pancreatic NETs (found in 82% of PHP patients). MEN1 pathogenic variants in exon 10 represented an independent risk factor for PHP recurrence. A single pediatric study in MEN1 (N = 80) revealed the following: a PHP rate of 80% and pancreatic NET rate of 35% and 35 underlying germline MEN1 pathogenic variants (and 3/35 of them were newly detected). The co-occurrence of genetic anomalies included the following: CDC73 gene variant, glucokinase regulatory protein gene pathogenic variant (c.151C>T, p.Arg51*), and CAH-X syndrome. IR/metabolic feature-focused analysis identified (n = 10, N = 1010) a heterogeneous spectrum: approximately one-third of adults might have had prediabetes, almost half displayed some level of IR as reflected by HOMA-IR > 2.6, and serum calcium was positively correlated with HOMA-IR. Vitamin D deficiency was associated with a higher rate of metabolic syndrome (n = 1). Normocalcemic and mildly symptomatic hyperparathyroidism (n = 6, N = 193) was associated with a higher fasting glucose and some improvement after parathyroidectomy. This multilayer pancreas/parathyroid analysis highlighted a complex panel of connections from pathogenic factors, including biochemical, molecular, genetic, and metabolic factors, to a clinical multidisciplinary panel.

BACKGROUND: Multiple Endocrine Neoplasia type 1 (MEN1) is an autosomal dominant inherited disease with an estimated prevalence of 2-10:100 000. The main locations of tumors are parathyroid glands (HPT), gastroenteropancreatic tract (GEPT), and anterior pituitary gland (PT). The aim of our investigation was to describe the phenotype and genotype of Argentinian patients with MEN1.
METHODS: A total of 68 index patients diagnosed with at least two of the three main tumors or one tumor and a relative with MEN1, and 84 first-degree relatives were studied. We sequenced the coding region (exons 2-10); the promoter, exon 1; and the flanking intronic regions of the MEN1 gene, following the Sanger method. We used MLPA in index patients without mutation.
RESULTS: Prevalence of tumors: HPT 87.5%, GEPT 49% (p< 0.001). No statistical differences in the prevalence of HPT vs. PT (68%). Prevalence of pathogenic variants: 90% in familial cases and 51% in sporadic cases. Of the different 36 pathogenic variants, 13 (36.2%) were frameshift micro-rearrangement, 8 (22.2%) were missense, 9 (25%) were nonsense, 3 (8.3%) were mutations in splicing sites, 2 (5.5%) were large deletions and, 1 in-frame micro-rearrangement. We found 7 novel pathogenic variants. Thirty-nine percent (n = 33) of first-degree relatives of 23 families were found to be mutation carriers.
CONCLUSIONS: The phenotype and genotype of Argentinian patients was similar to other MEN1 populations. A high frequency of PT and the identification of seven novel mutations are underscored.
Introducción: La neoplasia endocrina múltiple tipo 1 (NEM1) es una enfermedad hereditaria autosómica dominante con una prevalencia estimada de 2-10:100 000. Las localizaciones principales de los tumores son glándulas paratiroides (HPT), tracto gastroenteropancreático (TGEP) y glándula pituitaria (TP). El objetivo de nuestra investigación fue describir el fenotipo y genotipo de pacientes argentinos con NEM1. Métodos: Estudiamos 68 casos índices diagnosticados por presentar al menos dos de los tres tumores principales, o un tumor y un pariente con NEM1, y 84 familiares de primer grado. Secuenciamos la región codificante (exones 2-10); el promotor, exón 1; y las regiones intrónicas flanqueantes del gen MEN1 siguiendo el método de Sanger. Utilizamos MLPA en pacientes índice sin mutación. Resultados: Prevalencia de tumores: HPT 87.5%, TGEP 49% (p < 0.001), sin diferencias estadísticas entre las prevalencias de HPT vs TP (68%). Prevalencia de variantes patogénicas: 90% en casos familiares y 51% en esporádicos. Hallamos 36 variantes patogénicas, 7 (20%) fueron noveles. Fueron 13 (36.2%) microarreglos con cambio en el marco de lectura, 9 (25%) variantes sin sentido, 8 (22.2%) con cambio de sentido, 3 (8.3%) en sitio de unión de empalme, 2 (5.5%) grandes deleciones y 1 microarreglo sin cambio en el marco de lectura. El 39 % (n = 33) de los parientes de primer grado en 23 familias fueron portadores de mutaciones. Conclusión: El fenotipo y genotipo de los pacientes argentinos con NEM1 fue similar al de otras poblaciones. Destacamos una alta frecuencia de TP y de variaciones patogénicas noveles.

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.

UNASSIGNED: Acute chest pain can be the first manifestation of multiple endocrine neoplasia type 1(MEN1)-associated thymic neuroendocrine neoplasms (NEN). Comprehensive treatment may be an effective strategy for MEN1-associated NEN.
UNASSIGNED: Multiple endocrine neoplasia type 1(MEN1)-associated thymic neuroendocrine neoplasms (NEN) is caused by the mutation of tumor suppressor MEN1 gene. Patients with MEN1-associated NEN initially presenting with acute chest pain are very rare. In the manuscript, we reported a case of a 45-year-old man who developed MEN1-associated NEN with acute chest pain as initial symptom. Thoracoscopic thymotomy was performed and thymic NEN was successfully removed. Genetic test showed a germline mutation of MEN1 gene in this patient. Immunohistochemical staining exhibited Syn(+), CgA(+), INSM1(+), CD56(+) and Ki67-positive cells (2%) in MEN1-associated NEN. Further evaluation unveiled MEN1-associated benign tumors including digestive NEN and pituitary gland adenoma. The 99mTc-HYNIC-TOC scintigraphy showed that focally increased radioactivity in the mid-upper abdomen. This patient was administered with 50Gy/25F of radiation dose to treat the postoperative lesions. Subsequently, sandostatin LAR (30 mg per week) was used as systemic therapy. He had no recurrence or metastasis for 6-month follow-up. Thus, acute chest pain can be the first manifestation of MEN1-associated NEN, and comprehensive treatment including surgery, radiation and systemic treatment may be an effective strategy for MEN1-associated NEN.