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.

Early detection of multiple endocrine neoplasia type 1: A case report.

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. CASE SUMMARY: 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. CONCLUSION: For patients who present with gastrointestinal symptoms accompanied by hypercalcemia and hypophosphatemia, clinicians need to be alert to the possibility of MEN1.

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.

Middle-segment preserving pancreatectomy: a literature review and case report.

PURPOSE: Middle segment-preserving pancreatectomy (MSPP) is a relatively new parenchymal-sparing surgery that has been introduced as an alternative to total pancreatectomy (TP) for multicentric benign and borderline pancreatic diseases. To date, only 36 cases have been reported in English. METHODS: We reviewed 22 published articles on MSPP and reported an additional case. RESULTS: Our patient was a 49-year-old Japanese man diagnosed with Zollinger-Elison syndrome (ZES) caused by duodenal and pancreatic gastrinoma associated with multiple endocrine neoplasia syndrome type 1. We avoided TP and chose MSPP as the operative technique due to his relatively young age. The patient developed a grade B postoperative pancreatic fistula (POPF), which improved with conservative treatment. He was discharged without further treatment. To date, no tumor has recurred, and pancreatic function seems to be maintained. According to a literature review, the morbidity rate of MSPP is as high as 54%, mainly due to the high incidence of POPF (32%). In contrast, there was no perioperative mortality, and postoperative pancreatic function was comparable to that after conventional pancreatectomy. CONCLUSIONS: Despite the high incidence of POPF, MSPP appears to be safe, with low perioperative mortality and good postoperative pancreatic sufficiency.

Turning Points in Cross-Disciplinary Perspective of Primary Hyperparathyroidism and Pancreas Involvements: Hypercalcemia-Induced Pancreatitis, MEN1 Gene-Related Tumors, and Insulin Resistance.

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.

Pancreatic GHRHomas in Patients with or without Multiple Endocrine Neoplasia Type 1 (MEN 1) : An Analysis of 36 Reported Cases.

Pancreatic GHRHomas (pGHRHomas) with acromegaly have unique conditions, harboring the existence of multiple endocrine neoplasia type 1 (MEN 1). Moreover, pituitary lesions are affected by both protracted ectopic GHRH and loss of menin function. Of significance is the clarification of clinicopathological aspects of pGHRHomas in patients with or without MEN 1. From 1977-2016, thirty-six patients with pGHRHomas were reported. Twenty-two out of 36 patients (61%) had pGHRHomas with MEN 1 and 14 patients did not. The former had a tendency of male predominance, benign tumor behavior and fewer metastasis rather than the latter. The latter is a single pGHRHoma accompanied by pituitary enlargement with somatotroph hyperplasia (hyperplasia) caused by protracted ectopic GHRH. Nine patients with MEN 1 underwent transsphenoidal surgery (TSS). The hyperplasia associated with various pituitary adenomas (PAs) including three GH-related adenomas was observed in seven subjects (32%). In these patients, the resection of their pGHRHomas was feasible. Furthermore, all patients with acromegaly due to pGHRHomas without MEN 1 had non-TSS, whereas approximately 70% of those with MEN 1 had unnecessary TSS. The association with hyperplasia and various PAs suggested that formation of the three GH-related adenomas may be induced by the foundations of MEN 1 gene mutations. J. Med. Invest. 71 : 1-8, February, 2024.

Heterogeneity of Multiple Pancreatic Neuroendocrine Tumors Identified by 68Ga-DOTANOC and 68Ga-Exendin-4 PET/CT in a Patient with Endogenous Hyperinsulinemic Hypoglycemia and Multiple Endocrine Neoplasia 1.

INTRODUCTION: Insulinomas are the most frequent functional pancreatic neuroendocrine tumors. In about 10% of cases, insulinomas are associated with hereditary syndromes, including multiple endocrine neoplasia 1 (MEN1). CASE PRESENTATION: Herein, we present a 44-year-old female with recurrent hypoglycemia. In December 1998, this patient underwent resection of two pancreatic lesions due to hypoglycemia and was diagnosed with insulinoma. After the operation, the symptoms of hypoglycemia disappeared. However, from 2021, hypoglycemic symptoms reappeared frequently, as did coma. In June 2023, enhanced CT showed multiple pancreatic lesions abundant with blood supply. Fasting serum blood glucose and insulin were 1.73 mmol/L and 15.2 U/L (2.6-11.8 U/L). Germline genes suggested MEN1 pathogenic mutations. 68Ga-DOTANOC PET/CT indicated there were multiple lesions located in the pancreas and duodenum with high expression of the somatostatin receptor (SSTR). 68Ga-exendin-4 PET/CT was added to localize the insulinoma. Most lesions with high expression of SSTR in the body and tail of the pancreas manifested parts of them with high uptake of 68Ga-exendin-4, and an additional lesion with high expression of glucagon-like peptide-1 receptor (GLP-1R) was only detected by 68Ga-exendin-4 PET/CT. It showed inter-tumor heterogeneity in the expression of SSTR and GLP-1R. From the distal pancreatectomy, a total of 5 tumors were found in the body and tail of the pancreas, which were diagnosed as neuroendocrine tumors (NETs). After the operation, all the symptoms related to hypoglycemia disappeared. Immunohistochemical results of SSTR2 and insulin were consistent with the imaging findings of dual-tracer PET/CT. CONCLUSION: From this case, a combination of 68Ga-DOTANOC and 68Ga-exendin-4 PET/CT was recommended in the patients with MEN1 and insulinoma to estimate the heterogeneity of multiple neuroendocrine tumors that contribute to detect all the NET lesions and locate the tumors with secretion of insulin.

[Comparative analysis of bone complications/manifestations in sporadic and MEN1-related primary hyperparathyroidism].

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) - is a rare syndrome with an autosomal dominant inheritance pattern caused by a mutation in the tumor suppressor gene (MEN1). Parathyroid involvement is the most common MEN1 manifestation resulting in primary hyperparathyroidism (mPHPT). Data on the prevalence and structure of bone disease in mPHPT compared to sporadic one (sPHPT) are often incomplete and contradictory. AIM: The purpose of this study was to compare the severity of bone involvement between mPHPT and sPHPT. MATERIALS AND METHODS: A single-center retrospective study was conducted among young patients in the active phase of PHPT and without prior parathyroidectomy in anamnesis. The analysis included the main parameters of calcium-phosphorus metabolism, bone remodeling markers, as well as an assessment of disease complications. Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry (DXA) at sites of lumbar spine, femur and radius. Trabecular bone score (TBS) was applied to estimate trabecular microarchitecture. All patients included in the study underwent genetic testing. RESULTS: Group 1 (mPHPT) included 26 patients, and group 2 (sSHPT) included 30 age-matched patients: the median age in group 1 was 34.5 years [25; 39], in group 2 - 30.5 years [28; 36], (p=0.439, U-test). Within group 1, the subgroup 1A (n=21) was formed with patients without other hormone-produced neuroendocrine neoplasms (NEN) in the gastrointestinal tract (GI) and the anterior pituitary gland. The duration of PHPT was comparable in both groups: mPHPT - 1 year [0; 3] versus sPHPT - 1 year [0; 1], (p=0.533, U-test). There were no differences in the main parameters of calcium-phosphorus metabolism, as well as in the prevalence of kidney complications. In the mPHPT group, bone abnormalities were observed significantly more often compared to sPHPT: 54 vs 10% (p=<0.001; F-test). Statistically significant differences were revealed both in BMD and in Z-score values of the femoral neck and total hip, which were lower in the mPHPT group. These differences remained significant when comparing subgroup 1A with sPHPT. CONCLUSION: MEN1-associated PHPT may be accompanied by a more severe decrease in BMD in the femoral neck and total hip compared to sPHPT regardless of the other hormone-producing NEN. Clarifying the role of mutation in the MEN1 gene in these processes requires further study.

Microwave ablation for recurrent primary hyperparathyroidism in four patients with multiple endocrine neoplasia type 1: a case series report.

Multiple endocrine neoplasia type 1 (MEN1), a rare tumor syndrome, is inherited in an autosomal dominant pattern, mainly manifested as primary hyperparathyroidism (PHPT). Surgery is preferred for patients with MEN1 and PHPT. Thermal ablation has been widely applied for PHPT but rarely for postoperative recurrent PHPT in MEN1 patients. Based on a series of cases, we aimed to investigate the clinical efficacy and safety of ultrasound-guided percutaneous microwave ablation in the treatment of MEN1 patients with postoperative recurrence of PHPT.

Recurrence After Surgery for Primary Hyperparathyroidism in 517 Patients With Multiple Endocrine Neoplasia Type 1: An Association Francophone de Chirurgie Endocrinienne and Groupe d'étude des Tumeurs Endocrines study.

OBJECTIVE: To assess recurrence according to the type of surgery for primary hyperparathyroidism (pHPT) in multiple endocrine neoplasia type 1 ( MEN1 ) patients and to identify the risk factors for recurrence after the initial surgery. BACKGROUND: In MEN1 patients, pHPT is multiglandular, and the optimal extent of initial parathyroid resection influences the risk of recurrence. METHODS: MEN1 patients who underwent initial surgery for pHPT between 1990 and 2019 were included. Persistence and recurrence rates after less than subtotal parathyroidectomy (LTSP) and subtotal parathyroidectomy (STP) were analyzed. Patients with total parathyroidectomy with reimplantation were excluded. RESULTS: Five hundred seventeen patients underwent their first surgery for pHPT: 178 had LTSP (34.4%) and 339 STP (65.6%). The recurrence rate was significantly higher after LTSP (68.5%) than STP (45%) ( P < 0.001). The median time to recurrence after pHPT surgery was significantly shorter after LTSP than after STP: 4.25 (1.2-7.1) versus 7.2 (3.9-10.1) years ( P < 0.001). A mutation in exon 10 was an independent risk factor of recurrence after STP (odds ratio = 2.19; 95% CI: 1.31; 3.69; P = 0.003). The 5 and 10-year recurrent pHPT probabilities were significantly higher in patients after LTSP with a mutation in exon 10 (37% and 79% vs 30% and 61%; P = 0.016). CONCLUSIONS: Persistence, recurrence of pHPT, and reoperation rate are significantly lower after STP than LTSP in MEN1 patients. Genotype seems to be associated with the recurrence of pHPT. A mutation in exon 10 is an independent risk factor for recurrence after STP, and LTSP may not be recommended when exon 10 is mutated.

The risk of concurrent malignancies in patients with multiple endocrine neoplasia type 1: insights into clinical characteristics of those with multiple endocrine neoplasia type 1.

OBJECTIVE: Summarize and analyze the characteristics of patients with Multiple Endocrine Neoplasia type 1 (MEN-1) who were diagnosed with malignant tumors that do not belong to MEN-1 components. METHODS: Clinical data from patients with MEN-1 who visited Peking Union Medical College Hospital between April 2012 and April 2022 were collected. We compared the clinical characteristics of patients with malignant tumors outside of their MEN-1 components to those without additional tumors. MEN-1 gene testing was performed on most of these patients using Sanger sequencing, whole-exome sequencing, or MLPA. RESULTS: A total of 221 MEN-1 patients were diagnosed, of which 23 (10.40%) were found to have malignant tumors that did not belong to MEN-1 components, including papillary thyroid carcinoma (PTC) (4.52%), breast cancer (1.81%), urologic neoplasms (1.35%), primary hepatic carcinoma (PCC) (0.09%), meningeal sarcoma (0.05%), glioblastoma (0.05%), cervical cancer (0.05%), and lung carcinoma (0.05%). MEN-1 gene mutations were identified in 11 patients, including missense mutations, frameshift mutations, and splice mutations. The prevalence of each endocrine neoplasm, particularly gastroenteropancreatic neuroendocrine tumor, was higher in MEN-1 patients with other malignant tumors compared to MEN-1 patients without malignant tumors. CONCLUSION: Our retrospective study revealed a higher incidence of non-MEN-1 component malignant tumors in MEN-1 patients, especially breast cancer, PTC, and urologic neoplasms. These patients also exhibit more severe clinical phenotypes of MEN-1.

Primary hyperparathyroidism in patients with multiple endocrine neoplasia type 1: Impact of genotype and surgical approach on long-term postoperative outcomes.

BACKGROUND: Protein-truncating germline pathogenic variants in the N- and C-terminal exons (2, 9, and 10) of the MEN1 gene may be associated with aggressive pancreatic neuroendocrine tumors. However, the impact of these variants on parathyroid disease is poorly understood. We sought to investigate the effects of genotype and surgical approach on clinical phenotype and postoperative outcomes in patients with multiple endocrine neoplasia type 1 (MEN1)-related primary hyperparathyroidism. METHODS: We identified patients with MEN1 evaluated at our institution from 1985 to 2020 and stratified them by genotype, (truncating variants in exons 2, 9, or 10, or other variants), and index surgical approach, (less-than-subtotal parathyroidectomy [

Recurrent Primary Hyperparathyroidism in Multiple Endocrine Neoplasia Type 1 Syndrome.

Primary hyperparathyroidism is a common endocrinopathy. Multiple Endocrine Neoplasia Type 1 (MEN1) is a rare autosomal dominantly inherited endocrine tumor predisposition syndrome, with one of main manifestations being primary hyperparathyroidism. We retrospectively evaluated a set of 1011 patients who underwent surgery for primary hyperparathyroidism between the years 2018-2022, and found 78 (8 %) patients who underwent reoperations and 27 patients with MEN1 syndrome. In the group of patients with MEN1 syndrome, 7 (35 %) needed reoperations. Patients with multiple endocrine neoplasia syndrome have a higher risk of needing reoperation. Genetic testing can help identify MEN1 syndrome preoperatively and to better evaluate the approach to surgery.

[Predicting the presence of MEN1 gene mutation based on the clinical phenotype of patients with primary hyperparathyroidism].

BACKGROUND: Timely referral of patients for genetic testing to rule out MEN1-associated primary PHPT is important factor in determining treatment strategy and prognosis. In the context of the limited availability of genetic testing, the search for clinical markers indicative of MEN1 gene mutations remains an extremely relevant task. AIM: To determine the diagnostic value of clinical features of primary PHPT in young patients for predicting the presence of MEN1 gene mutations. MATERIALS AND METHODS: A single-center, prospective study was conducted at the Endocrinology Research Centre, involving 273 patients with PHPT in the period 2015-2022. Based on the results of genetic and laboratory tests, patients were divided into three groups: those with MEN1 gene mutations (MEN+ group, n=71), those without MEN1 gene mutations - isolated sporadic PHPT (MEN- group, n=158), and patients with PHPT and associated endocrine gland disorders - MEN-1 syndrome phenocopies (PHEN group, n=32). Subgroups of patients younger than 40 years of age were also identified. Comparative analysis was performed among the independent groups and subgroups, and logistic regression analysis was used to develop a mathematical model for predicting the probability of the presence of MEN1 gene mutation. RESULTS: Patients in the MEN+ and MEN- groups were comparable by gender and age at manifestation, as well as calcium-phosphorus metabolism parameters and PHPT complications. In the PHEN group, PHPT manifested at older age compared to the other groups (p<0.001 for all), with lower total calcium levels and a trend toward lower iPTH concentrations. The MEN+ group had a significantly higher frequency of multiglandular parathyroid (PG) involvement, PHPT recurrence, and positive family history compared to the MEN- and PHEN groups. Histologically, adenomas predominated in the PHEN and MEN- groups (92% and 94%, respectively), whereas hyperplasia of PGs were more common in the MEN+ group (49%). None of the PHEN patients had all three «classic¼ components of the MEN-1 syndrome, and the clinical course of PHPT was similar to that of the MEN- group. These differences were also observed in the subgroups of patients younger than 40 years, which formed the basis for the development of a mathematical model. The logistic regression equation for predicting the probability of the presence of the MEN1 gene mutation included eight predictors, with a diagnostic sensitivity of 96% and specificity of 98%. CONCLUSION: Based on the analysis performed, eight hereditary predictors of PHPT within the MEN-1 syndrome were identified. A mathematical model was developed to predict the presence of the MEN1 gene mutation in patients, which demonstrated high classification performance on the training dataset. Further refinement of the model will help improve the quality of medical care for patients with PHPT.

Ultrasound-guided microwave ablation in the treatment of recurrent primary hyperparathyroidism in a patient with MEN1: a case report.

Background: Multiple endocrine neoplasia type 1 (MEN1) is an inherited endocrine syndrome caused by the mutation in the tumor suppressor gene MEN1. The recurrence rate of primary hyperparathyroidism (PHPT) in patients with MEN1 after parathyroidectomy remains high, and the management of recurrent hyperparathyroidism is still challenging. Case presentation: We reported a 44-year-old woman with MEN1 combined with PHPT who was diagnosed through genetic screening of the patient and her family members. After parathyroidectomy to remove one parathyroid gland, the patient suffered from persistent high levels of serum calcium and parathyroid hormone, which returned to normal at up to 8 months after ultrasound-guided microwave ablation (MWA) for bilateral parathyroid glands, suggesting an acceptable short-term prognosis. Conclusion: Ultrasound-guided MWA for parathyroid nodules may be an effective therapeutic strategy for recurrent PHPT in MEN1 patients.

Thymoma in multiple endocrine neoplasia type 1: a case report and systematic review.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare syndrome that combines endocrine and non-endocrine tumors. Thymic neuroendocrine tumors are uncommon components that predict poor prognosis in patients with MEN1. We aimed to summarize the clinical characteristics of thymoma in MEN1 by reviewing the current reports from the literature. METHODS: A patient with multiple endocrine neoplasia type 1 (parathyroid hyperplasia, pituitary adenoma, and insulinoma) was found to have a 2 × 1.5 cm thymic mass during long-term follow-up. Thoracoscope surgery was performed, and a histopathology examination revealed WHO Type B3 thymoma. A pathogenic mutation of c.783 + 1G > A in the MEN1 gene was identified. We further searched PubMed and EMBASE for thymoma in association with MEN1. RESULTS: A comprehensive overview of the literature concerning characteristics of MEN1-related thymoma was summarized. Clinical characteristics and differences between thymoma and thymic carcinoid are highlighted. CONCLUSIONS: Besides carcinoid, other tumors, including thymoma, need to be identified for thymic space-occupying lesions in MEN1 patients. The impact of thymoma on the long-term prognosis of MEN1 patients needs further investigation.

[Rare forms of hereditary endocrine neoplasia: co-existence of pituitary adenoma and pheochromocytoma/paraganglioma].

Functioning pituitary adenomas and pheochromocytomas/paragangliomas are rare in the general population. Pituitary adenomas occur in the familial setting in approximately 5% of cases, whereas pheochromocytomas/paragangliomas can be hereditary in 30-40% of cases. Hereditary syndromes associated with pituitary adenomas include multiple endocrine neoplasia types 1 and 4, familial isolated pituitary adenomas, and Carney complex. Hereditary syndromes associated with pheochromocytomas/paragangliomas and genes, mutations in which predispose to their development, are more numerous. The first clinical descriptions of the co-occurrence of pituitary adenoma and pheochromocytoma/paraganglioma in one patient date back to the mid 20th century, however delineating such a co-occurrence into a particular syndrome («3PAs¼ (pituitary adenoma, pheochromocytoma, paraganglioma)) was suggested only in 2015. To date, approximately 100 cases of such a co-occurrence have been described in the literature. Mutations in genes encoding subunits of succinate dehydrogenase complex II (SDHx) are revealed in the majority of cases, much less common are mutations in MAX, MEN1 and some other genes. This review summarizes the current information on the «3PAs¼ syndrome.

Expressions of Cushing's syndrome in multiple endocrine neoplasia type 1.

Cushing's syndrome (CS) resulting from endogenous hypercortisolism can be sporadic or can occur in the context of familial disease because of pituitary or extra-pituitary neuroendocrine tumors. Multiple endocrine neoplasia type 1 (MEN1) is unique among familial endocrine tumor syndromes because hypercortisolism in this context can result from pituitary, adrenal, or thymic neuroendocrine tumors and can therefore reflect either ACTH-dependent or ACTH-independent pathophysiologies. The prominent expressions of MEN1 include primary hyperparathyroidism, tumors of the anterior pituitary, gastroenteropancreatic neuroendocrine tumors, and bronchial carcinoid tumors along with several common non-endocrine manifestations such as cutaneous angiofibromas and leiomyomas. Pituitary tumors are present in about 40% of MEN1 patients, and up to 10% of such tumors secrete ACTH that can result in Cushing's disease. Adrenocortical neoplasms occur frequently in MEN1. Although such adrenal tumors are mostly clinically silent, this category can include benign or malignant tumors causing hypercortisolism and CS. Ectopic tumoral ACTH secretion has also been observed in MEN1, almost exclusively originating from thymic neuroendocrine tumors. The range of clinical presentations, etiologies, and diagnostic challenges of CS in MEN1 are reviewed herein with an emphasis on the medical literature since 1997, when the MEN1 gene was identified.