Phenotype and genotype of patients with multiple endocrine neoplasia type 1 studied in Argentina.

INTRODUCTION: 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. CONCLUSION: 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.

A Cohort Study of CNS Tumors in Multiple Endocrine Neoplasia Type 1.

PURPOSE: Multiple endocrine neoplasia type 1 (MEN1) is thought to increase the risk of meningioma and ependymoma. Thus, we aimed to describe the frequency, incidence, and specific clinical and histological features of central nervous system (CNS) tumors in the MEN1 population (except pituitary tumors). EXPERIMENTAL DESIGN: The study population included patients harboring CNS tumors diagnosed with MEN1 syndrome after 1990 and followed up in the French MEN1 national cohort. The standardized incidence ratio (SIR) was calculated based on the French Gironde CNS Tumor Registry. Genomic analyses were performed on somatic DNA from seven CNS tumors, including meningiomas and ependymomas from patients with MEN1, and then on 50 sporadic meningiomas and ependymomas. RESULTS: A total of 29 CNS tumors were found among the 1,498 symptomatic patients (2%; incidence = 47.4/100,000 person-years; SIR = 4.5), including 12 meningiomas (0.8%; incidence = 16.2/100,000; SIR = 2.5), 8 ependymomas (0.5%; incidence = 10.8/100,000; SIR = 17.6), 5 astrocytomas (0.3%; incidence = 6.7/100,000; SIR = 5.8), and 4 schwannomas (0.3%; incidence = 5.4/100,000; SIR = 12.7). Meningiomas in patients with MEN1 were benign, mostly meningothelial, with 11 years earlier onset compared with the sporadic population and an F/M ratio of 1/1. Spinal and cranial ependymomas were mostly classified as World Health Organization grade 2. A biallelic MEN1 inactivation was observed in 4/5 ependymomas and 1/2 meningiomas from patients with MEN1, whereas MEN1 deletion in one allele was present in 3/41 and 0/9 sporadic meningiomas and ependymomas, respectively. CONCLUSIONS: The incidence of each CNS tumor was higher in the MEN1 population than in the French general population. Meningiomas and ependymomas should be considered part of the MEN1 syndrome, but somatic molecular data are missing to conclude for astrocytomas and schwannomas.

Beyond MEN1, When to Think About MEN4? Retrospective Study on 5600 Patients in the French Population and Literature Review.

CONTEXT: Germline CDKN1B variants predispose patients to multiple endocrine neoplasia type 4 (MEN4), a rare MEN1-like syndrome, with <100 reported cases since its discovery in 2006. Although CDKN1B mutations are frequently suggested to explain cases of genetically negative MEN1, the prevalence and phenotype of MEN4 patients is poorly known, and genetic counseling is unclear. OBJECTIVE: To evaluate the prevalence of MEN4 in MEN1-suspected patients and characterize the phenotype of MEN4 patients. DESIGN: Retrospective observational nationwide study. Narrative review of literature and variant class reassessment. PATIENTS: We included all adult patients with class 3/4/5 CDKN1B variants identified by the laboratories from the French Oncogenetic Network on Neuroendocrine Tumors network between 2015 and 2022 through germline genetic testing for MEN1 suspicion. After class reassessment, we compared the phenotype of symptomatic patients with class 4/5 CDKN1B variants (ie, with genetically confirmed MEN4 diagnosis) in our series and in literature with 66 matched MEN1 patients from the UMD-MEN1 database. RESULTS: From 5600 MEN1-suspected patients analyzed, 4 with class 4/5 CDKN1B variant were found (0.07%). They presented with multiple duodenal NET, primary hyperparathyroidism (PHPT) and adrenal nodule, isolated PHPT, PHPT, and pancreatic neuroendocrine tumor. We listed 29 patients with CDKN1B class 4/5 variants from the literature. Compared with matched MEN1 patients, MEN4 patients presented lower NET incidence and older age at PHPT diagnosis. CONCLUSION: The prevalence of MEN4 is low. PHPT and pituitary adenoma represent the main associated lesions, NETs are rare. Our results suggest a milder and later phenotype than in MEN1. Our observations will help to improve genetic counseling and management of MEN4 families.

Regional Growth Velocity and Incidence of Pancreatic Neuroendocrine Neoplasias in Multiple Endocrine Neoplasia Type 1.

OBJECTIVES: Pancreatic neuroendocrine neoplasias (pNENs) in multiple endocrine neoplasia type 1 are predominantly found in the dorsal anlage. Whether their growth velocity and incidence might be related to their location in the pancreas has not been investigated yet. METHODS: We studied 117 patients using endoscopic ultrasound. RESULTS: Growth velocity could be calculated for 389 pNENs. Increase of largest tumor diameter (% per month) was 0.67 (standard deviation [SD], 2.04) in the pancreatic tail (n = 138), 1.12 (SD, 3.00) in the pancreatic body (n = 100), 0.58 (SD, 1.19) in the pancreatic head/uncinate process-dorsal anlage (n = 130), and 0.68 (SD, 0.77) in the pancreatic head/uncinate process-ventral anlage (n = 12). Comparing growth velocity of all pNENs in the dorsal (n = 368, 0.76 [SD, 2.13]) versus ventral anlage, no significant difference was detected. Annual tumor incidence rate was 0.21 in the pancreatic tail, 0.13 in the pancreatic body, 0.17 in the pancreatic head/uncinate process-dorsal anlage, 0.51 dorsal anlage together, and 0.02 in the pancreatic head/uncinate process-ventral anlage. CONCLUSIONS: Multiple endocrine neoplasia type 1 pNENs are unequally distributed between ventral (low prevalence and incidence) and dorsal anlage. However, there are no regional differences in growth behavior.

A Blood-based Polyamine Signature Associated With MEN1 Duodenopancreatic Neuroendocrine Tumor Progression.

CONTEXT: Duodenopancreatic neuroendocrine tumors (dpNETs) frequently occur in patients with multiple endocrine neoplasia type 1 (MEN1), and metastatic dpNET is the primary cause of disease-related mortality. There is a need for biomarkers that can identify patients with MEN1-related dpNETs that are at high risk of developing distant metastasis. Polyamines have tumor-promoting roles in several cancer types. OBJECTIVE: We hypothesized that MEN1-dpNET-related disease progression is associated with elevated levels of circulating polyamines. METHODS: Through an international collaboration between The University of Texas MD Anderson Cancer Center, the National Institutes of Health, and the University Medical Center Utrecht, plasma polyamine levels were assessed using mass spectrometry in 84 patients with MEN1 (20 with distant metastatic dpNETs [patients] and 64 with either indolent dpNETs or no dpNETs [controls]). A mouse model of MEN1-pNET, Men1fl/flPdx1-CreTg, was used to test time-dependent changes in plasma polyamines associated with disease progression. RESULTS: A 3-marker plasma polyamine signature (3MP: N-acetylputrescine, acetylspermidine, and diacetylspermidine) distinguished patients with metastatic dpNETs from controls in an initial set of plasmas from the 3 participating centers. The fixed 3MP yielded an area under the curve of 0.84 (95% CI, 0.62-1.00) with 66.7% sensitivity at 95% specificity for distinguishing patients from controls in an independent test set from MDACC. In Men1fl/flPdx1-CreTg mice, the 3MP was elevated early and remained high during disease progression. CONCLUSION: Our findings provide a basis for prospective testing of blood-based polyamines as a potential means for monitoring patients with MEN1 for harboring or developing aggressive disease.

Patients With MEN1 Are at an Increased Risk for Venous Thromboembolism.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited disorder predisposing the development of multiple functional and nonfunctional neuroendocrine tumors (NETs). Only uncommon MEN1-associated functional NETs such as glucagonomas (<1%) and adenocorticotropic hormone-producing tumors (<5%) are known to be associated with hypercoagulability. It is unknown if patients with MEN1 generally have an increased risk of venous thromboembolism (VTE). METHODS: We queried a prospective natural history study of germline mutation-positive MEN1 patients (n = 286) between 1991 and 2019 for all lifetime events of VTE. The search terms were: DVT, thromb, embol, PE, pulmonary embolism, clot, hematology consult, anticoagulant, coumadin, lovenox, xarelto, warfarin, aspirin, rivaroxaban, and apixaban. Incidence rates were calculated, accounting for age and sex. Comparisons were made to published incidence rates in healthy populations, different types of cancer, and Cushing's syndrome. RESULTS: Thirty-six subjects (median age 45 years, range 16-75) experienced a VTE event, yielding a prevalence rate of 12.9%. The age-sex adjusted incidence rate of VTE is 9.11 per 1000 patient-years, with a sex-adjusted lifetime incidence rate of 2.81 per 1000 patient-years. MEN1-associated lifetime incidence rates are ~2-fold higher than the estimated annual incidence rate in the general population and are comparable to the known risk in the setting of various types of cancer. Approximately 80% of patients who had a VTE were diagnosed with pancreatic NETs, of which 24% were insulinomas. Fourteen patients (42%) experienced perioperative VTE events. CONCLUSIONS: MEN1 patients have an increased risk of VTE. Further mechanistic investigation and validation from other MEN1 cohorts are needed to confirm the increased prevalence of VTE in MEN1.

ARMC5 Alterations in Patients With Sporadic Neuroendocrine Tumors and Multiple Endocrine Neoplasia Type 1 (MEN1).

CONTEXT: Adrenal lesions are frequent among patients with sporadic neuroendocrine tumors (spNETs) or multiple endocrine neoplasia type 1 (MEN1). Armadillo repeat-containing 5 (ARMC5)-inactivating variants cause adrenal tumors and possibly other neoplasms. OBJECTIVE: The objective of this work is to investigate a large cohort spNETs or MEN1 patients for changes in the ARMC5 gene. PATIENTS AND METHODS: A total of 111 patients, 94 with spNET and 17 with MEN1, were screened for ARMC5 germline alterations. Thirty-six tumors (18 spNETs and 18 MEN1 related) were collected from 20 patients. Blood and tumor DNA samples were genotyped using Sanger sequencing and microsatellite markers for chromosomes. ARMC5 and MEN1 expression were assessed by immunohistochemistry. RESULTS: In 76 of 111 (68.4%) patients, we identified 16 different ARMC5 germline variants, 2 predicted as damaging. There were no differences in the prevalence of ARMC5 variants depending on the presence of MEN1-related adrenal lesions. Loss of heterozygosity (LOH) at chromosome 16p and ARMC5 germline variants were present together in 23 or 34 (67.6%) tumors; in 7 of 23 (30.4%) their presence led to biallelic inactivation of the ARMC5 gene. The latter was more prevalent in MEN1-related tumors than in spNETs (88.9% vs 38.9%; P = .005). LOH at the chromosome 16p (ARMC5) and 11q (MEN1) loci coexisted in 16/18 MEN1-related tumors, which also expressed lower ARMC5 (P = .02) and MEN1 (P = .01) proteins compared to peritumorous tissues. CONCLUSION: Germline ARMC5 variants are common among spNET and MEN1 patients. ARMC5 haploinsufficiency or biallelic inactivation in spNETs and MEN1-related tumors suggests that ARMC5 may have a role in modifying the phenotype of patients with spNETs and/or MEN1 beyond its known role in macronodular adrenocortical hyperplasia.

The Relationship of Gastrinoma in MEN 1 to Helicobacter pylori infection.

CONTEXT: Helicobacter pylori and Multiple Endocrine Neoplasia Type 1 (MEN 1) are risk factors for hypergastrinemia. Gastrin-secreting neoplasms of the foregut mucosa are both a source of, and potentially stimulated by, hypergastrinemia. OBJECTIVE: To determine the relationship between H pylori exposure and the prevalence and severity of hypergastrinemia in patients with MEN 1. DESIGN, SETTING & PATIENTS: Cross-sectional analysis of patients with a common MEN1 gene mutation managed at a tertiary referral hospital that underwent fasting serum gastrin and H pylori serum IgG measurement. INTERVENTION: H pylori IgG and serum gastrin concentration, determined via immunoassay. MAIN OUTCOME MEASURES: The prevalence and severity of hypergastrinemia and its relationship to past H pylori exposure. RESULTS: Thirty-four of 95 (36%) patients were H pylori IgG seropositive. H pylori seropositive patients were significantly more likely to exhibit hypergastrinemia compared with seronegative patients (relative risk [RR] 1.72, P = .023). H pylori exposure also predicted severe hypergastrinemia (RR 3.52, P = .026 and RR 9.37, P = .031 for patients with gastrin ≥ ×4 and ≥ ×8 the upper limit of normal [ULN], respectively). Gastrin concentrations ≥ ×10 ULN occurred exclusively in H pylori seropositive patients (0/61 vs 6/34, P = .001). Serum gastrin and alpha subunit were positively associated in H pylori-exposed (ß = 0.69, P = .001), but not in H pylori-unexposed patients. CONCLUSION: Past H pylori exposure was associated with increased prevalence and severity of hypergastrinemia in MEN 1 patients. Past H pylori-related hypergastrinemia may contribute to the pathogenesis of ongoing gastrin hypersecretion by susceptible foregut neuroendocrine tissues.

La néoplasie endocrinienne multiple de type 1 : mise au point après le congrès de l'ENETS 2019: Multiple Endocrine Neoplasia Type 1: Development after the ENETS 2019 Congress.

Multiple Endocrine Neoplasia Type 1 (NEM1) is related to mutations of the menin gene. It is an autosomal dominant disease. Its prevalence is about 1/30 000 with a hugh penetrance. There is no genotype-phenotype correlation. This hereditary syndrome is characterized by the presence of tumors of the endocrine system (parathyroid, endocrine pancreas, pituitary and adrenal gland). Other disorders have also been described (bronchial and thymic carcinoid tumor, breast cancer, skin lesions). Management must take into account the specificities of these pathologies in NEM1 compared to sporadic forms (young age at diagnosis, multiple lesions within the same gland, multi-focal disease). © 2019 Published by Elsevier Masson SAS. All rights reserved. Cet article fait partie du numéro supplément Les Must de l'Endocrinologie 2019 réalisé avec le soutien institutionnel de Ipsen-Pharma.

True MEN1 or phenocopy? Evidence for geno-phenotypic correlations in MEN1 syndrome.

PURPOSE: Multiple endocrine neoplasia type 1 is a rare tumor syndrome caused by germline mutations of MEN1 gene. Phenotype varies widely, and no definitive correlation with the genotype has been observed. Mutation-negative patients with MEN1-associated tumors represent phenocopies. By comparing mutation-positive and mutation-negative patients, we aimed to identify phenotype features predictive for a positive genetic test and to evaluate the role of MEN1 mutations in phenotype modulation. METHODS: Mutation screeening of MEN1 gene by Sanger sequencing and assessment of clinical data of 189 consecutively enrolled probands and relatives were performed at our national and European Reference Center. Multiple ligation probe amplification analysis of MEN1 gene and Sanger sequencing of CDKN1B were carried out in clinically suspicious but MEN1-negative cases. RESULTS: Twenty-seven probands and twenty family members carried MEN1 mutations. Five mutations have not been described earlier. Pronouncedly high number of phenocopies (>70%) was observed. Clinical suspicion of MEN1 syndrome emerged at significantly earlier age in MEN1-positive compared to MEN1-negative probands. Gastroenteropancreatic neuroendocrine tumors developed significantly earlier and more frequently in carriers compared to non-carriers. Probands with high-impact (frameshift, nonsense, large deletions) mutations, predicted to affect menin function significantly, developed GEP-NETs more frequently compared to low-impact (inframe and missense) mutation carriers. CONCLUSIONS: MEN1 phenocopy is common and represents a significant confounder for the genetic testing. GEP-NET under 30 years best predicted a MEN1 mutation. The present study thus confirmed a previous proposal and suggested that GEP-NET under 30 years should be considered as a part of the indication criteria for MEN1 mutational analysis.

Pituitary adenomas in patients with multiple endocrine neoplasia type 1: a single-center experience in China.

PURPOSE: To explore the clinical characteristics of pituitary adenomas in patients with MEN1 and to summarize treatment strategies for MEN1 in a Chinese population. METHODS: We retrospectively analyzed 54 MEN1 patients with pituitary adenomas diagnosed at Peking Union Medical College Hospital from March 2003 to January 2017. Clinical data, laboratory testing results, treatments of involved glands and treatment responses were collected and analyzed. RESULTS: The mean age at pituitary adenoma diagnosis was 53.9 ± 17.8. The patients initially consulted the Endocrinology, General Surgery and Neurosurgery departments, in descending frequency. The nonfunctioning adenoma, prolactinoma, GH-secreting adenoma, cosecreting adenoma, and ACTH-secreting adenoma subtypes accounted for 48.1%, 27.8%, 9.3%, 9.3% and 5.6% of the cases, respectively. The remission rate for prolactinomas was 46.2% (6/13) treated with bromocriptine. And the remission rates were 87.5% (7/8) and 100% (3/3) for GH-secreting adenomas and ACTH-secreting adenomas respectively achieved by transsphenoidal surgery. Nineteen (35.2%) patients with asymptomatic nonfunctioning pituitary adenomas showed no progression after a 35-month follow-up with close observation. Regarding treatment priority, patients with thymic carcinoid tumors received first-line surgery, 54% of the patients with enteropancreatic tumors had these tumors treated first, and 26% of all patients had their pituitary adenomas treated first. In acromegalic patients, pituitary lesions tended to be treated first (75%, p = 0.002). PHPT and adrenocortical adenomas can be managed with elective surgery. CONCLUSIONS: The treatment of MEN1 requires cooperation between multidisciplinary teams. Individualized treatment according to the severity of glandular involvement is needed. GH-secreting and ACTH-secreting pituitary adenomas require active treatment, while nonfunctioning pituitary adenomas can be observed closely.

Update on multiple endocrine neoplasia Type 1 and 2.

Multiple endocrine neoplasia type 1 is a rare genetic syndrome, characterized by the co-occurrence, in the same individual or in related individuals of the same family, of hyperparathyroidism, duodenopancraetic neuroendocrine tumors, pituitary adenomas, adrenocortical tumors, and neuroendocrine tumors (carcinoids) in the thymus, the bronchi, or the stomach. Multiple endocrine neoplastic type 2 is a rare genetic syndrome, characterized by the familial occurrence of medullary thyroid carcinoma either isolated or associated with pheochromocytoma, primary hyperparathyroidism, or typical features (Marfanoid habitus, mucosal neuromas). Subjects with clinical MEN1 and those who carry a mutation in the MEN1 gene should be offered biochemical and imaging screening in order to detect tumors and evaluate their progression over time. Children with mutation in the RET gene should have prophylactic total thyroidectomy according to the category of aggressiveness of the detected mutation whereas those with clinical MEN2 should be operated on upon diagnosis. In MEN1 patients, special attention should be paid to evaluate the progression duodenopancraetic neuroendocrine tumors because of their malignant potential. Also, thymic neuroendocrine tumors should be detected as soon as possible because they represent the most lethal tumor. In MEN2, calcitonin and carcinoembryonic antigen (CEA) serve as excellent tumor markers for medullary thyroid carcinoma. Their preoperative levels are correlated with tumor size and predict postoperative cure. Moreover, calcitonin or CEA doubling time has important prognostic value. In both MEN syndromes, multidisciplinary approaches are very important in the care of affected patients. Moreover, those patients should be comprehensively informed and enabled to participate in the decision-making procedure. In addition to multidisciplinary approaches, every effort should be made to follow the recommendations and guidelines issued by national (the French Group of Endocrine Tumors) and international groups.

Prognostic value of WHO grade in pancreatic neuro-endocrine tumors in Multiple Endocrine Neoplasia type 1: Results from the DutchMEN1 Study Group.

BACKGROUND: The prognostic value of WHO grade in pancreatic neuroendocrine tumors (PanNETs) in patients with Multiple Endocrine Neoplasia Type 1 (MEN1) is unknown. METHODS: We performed a cohort study using the Dutch National MEN1 database, which includes >90% of the Dutch MEN1 population with data collected between 1990 and 2014. Formalin-fixed paraffin embedded tissue blocks from the largest resected PanNET per patient were collected. MIB1 staining was performed and KI67 labeling index (LI) was determined by manual eye-counting under a microscope and by digital image analysis. Mitotic count was evaluated from hematoxylin & eosin stains. Association between WHO grade and (time until) development of liver metastases was calculated. RESULTS: Sixty-nine MEN1 patients who underwent pancreatic surgery were included. Ten patients (14%) developed liver metastases and all had PanNETs ≥3 cm. WHO G1, G2 and G3 PanNETs were seen in 83% (n = 57), 16% (n = 11) and 1% (n = 1) respectively. In non-functioning PanNETs >2 cm, liver metastases occurred in 80% of WHO G2 PanNETs (4/5) compared to 23% (5/22) in WHO G1 PanNETs (p = 0.03) when WHO grade was based on mitotic count only. This significant association was not seen for WHO grade based on Ki67 LI. After five years, liver metastases in non-functioning PanNETs were not seen in tumors ≤2 cm, in 10% of the large WHO G1 (according to mitotic count only) tumors and in 60% of large WHO G2 tumors (p-value 0.000). CONCLUSION: High mitotic count is correlated with poor prognosis in MEN1 patients with large non-functioning PanNETs.

Neoplasia endocrina múltiple tipo 1 con mutación negativa y fenocopias / Multiple endocrine neoplasia type 1 with negative mutation and phenocopies

Introducción: existen 4 tipos de neoplasias endocrinas múltiples, las cuales se caracterizan por la aparición de tumores en 2 o más glándulas endocrinas. La prevalencia de neoplasia endocrina múltiple 1 es aproximadamente 2 por 100 000, y constituyen una enfermedad poco frecuente. Objetivo: descartar, ante la sospecha de una neoplasia endocrina múltiple 1 con mutación negativa, otras enfermedades para poder diagnosticarla como tal. Presentación del caso clínico: mujer de 36 años, con diagnóstico de macroprolactinoma e hiperparatiroidismo primario normocalcémico (neoplasia endocrina múltiple 1 clínica), hallazgos clínicos que justificaron el estudio genético. Inicialmente para neoplasia endocrina múltiple 1, resultó negativo. En pacientes con neoplasia endocrina múltiple 1 clínica -o alta sospecha de neoplasia endocrina múltiple 1 en los que no se identifica mutación- hay que considerar que se trate de una fenocopia y ampliar el estudio genético: CDC73, CDKN1B, CaSR y AIP. También se analizaron estos genes, y fueron negativos. Otra entidad a considerar sería el hiperparatiroidismo aislado familiar. Conclusiones: llegar al diagnóstico de neoplasia endocrina múltiple 1 a veces no es tan simple, como identificar una mutación positiva. Es importante descartar fenocopias, para poder diagnosticar correctamente al paciente, pues esto determinará el seguimiento en búsqueda de otros posibles tumores, lo que -en último término- puede condicionar el pronóstico(AU)

Introduction: there are four types of multiple endocrine neoplasias which are characterized by occurrence of tumors in two or more endocrine glands. The prevalence rate of multiple endocrine neoplasia type 1 is 2 per 100 000 patients approximately and it is a rare disease. Objective: to rule out the existence of any other disease in order to properly diagnose a suspected multiple endocrine neoplasia type 1 with negative mutation. Clinical case presentation: a 36 years-old woman diagnosed with macroprolactinoma and primary normocalcemic hyperparathyroidism (clinical multiple endocrine neoplasia type 1) and clinical findings supporting the performance of a genetic study. The study initially yielded negative results for the above-mentioned disease. However, in those patients with clinical multiple endocrine neoplasia type 1- or high suspicious of multiple endocrine neoplasia type 1 with no identified mutation- it must be considered that there is a phenocopy and the genetic study must be extended to include CDC 73, CDKN1B, CaSR and AIP. These genes were also analyzed with negative results. Another disease to be considered would be isolated family hyperparathyroidism. Conclusions: making the diagnosis of a multiple endocrine neoplasia type 1 is not sometimes as simple as identifying a positive mutation. It is important to rule out possible phenocopies to be able to adequately diagnose a patient, since this will determine the search for other probable tumors which may ultimately influence this prognosis(AU)

MEN1 redefined, a clinical comparison of mutation-positive and mutation-negative patients.

BACKGROUND: Multiple Endocrine Neoplasia type 1 (MEN1) is diagnosed when two out of the three primary MEN1-associated endocrine tumors occur in a patient. Up to 10-30 % of those patients have no mutation in the MEN1 gene. It is unclear if the phenotype and course of the disease of mutation-negative patients is comparable with mutation-positive patients and if these patients have true MEN1. The present study aims to describe and compare the clinical course of MEN1 mutation-negative patients with two out of the three main MEN1 manifestations and mutation-positive patients during long-term follow-up. METHODS: This is a cohort study performed using the Dutch MEN1 database, including > 90 % of the Dutch MEN1 population. RESULTS: A total of 293 (90.7 %) mutation-positive and 30 (9.3 %) mutation-negative MEN1 patients were included. Median age of developing the first main MEN1 manifestation was higher in mutation-negative patients (46 vs. 33 years) (P = 0.007). Mutation-negative patients did not develop a third main MEN1 manifestation in the course of follow-up compared to 48.3 % of mutation-positive patients (P < 0.001). Median survival in mutation-positive patients was estimated at 73.0 years (95 % CI, 69.5-76.5) compared to 87.0 years (95 % CI not available) in mutation-negative patients (P = 0.001). CONCLUSIONS: Mutation-positive and mutation-negative MEN1 patients have a different phenotype and clinical course. Mutation-negative patients develop MEN1 manifestations at higher age and have a life expectancy comparable with the general population. The apparent differences in clinical course suggest that MEN1 mutation-negative patients do not have true MEN1, but another MEN1-like syndrome or sporadic co-incidence of two neuro-endocrine tumors.

Clinical Features, Treatments, and Outcomes of Patients with Thymic Carcinoids and Multiple Endocrine Neoplasia Type 1 Syndrome at MD Anderson Cancer Center.

Thymic carcinoids are rare neuroendocrine tumors that occur in 1-5 % of patients with multiple endocrine neoplasia type 1 (MEN1) and are a major cause of morbidity and mortality. The few published reports associate these tumors with male sex and smoking. Our objective was to describe cases of these tumors treated at our institution. We performed a retrospective chart review of all patients diagnosed with MEN1 at our tertiary referral center from 1980 to 2014. Patients with a histopathologic, fine-needle aspiration, or clinical diagnosis of a thymic carcinoid were included. Two hundred ninety-one patients fulfilled the criteria for a diagnosis of MEN1. Clinicopathologic characteristics, MEN1 genetic testing results, treatments, and survival rates were analyzed. Nine patients had a thymic carcinoid, six men (67 %) and three women (33 %). Six patients were non-smokers (67 %). Two patients had synchronous (22 %) and eight patients (89 %) had metachronous distant metastasis. The 10-year overall survival rate was 45 % (lower 95 % upper 95 % CI 20-100 %). The 10-year disease-free survival rate was 42 % (lower 95 % upper 95 % CI 15-100 %). Five patients had MEN1 genetic testing, and the genotypes of affected individuals were p.W341X, c.275_286delGCTTCACCGCCC, p.R98X, c.1350+(1_11)del11, and partial duplication of exons 9 and 10. A higher percentage of MEN1-related thymic carcinoids can occur in women and in non-smokers than previously reported. Both novel and known mutations were present in our cohort. Eighty nine percent of patients developed a metachronous metastasis from the thymic carcinoid. Patients with MEN1 and thymic carcinoids should be followed closely.

Impact of Delay in Diagnosis in Outcomes in MEN1: Results From the Dutch MEN1 Study Group.

OBJECTIVE: Identifying a germline mutation in the multiple endocrine neoplasia type 1 (MEN1) gene in an index case has consequences for a whole family. Eligible family members should be offered genetic counseling and MEN1 mutation testing. Subsequently, clinical screening of mutation carriers according to the guidelines should be initiated. We assessed whether there is a lag time from MEN1 diagnosis of the index case to MEN1 diagnosis of family members. In addition, we determined whether this lag time was associated with an increased morbidity and mortality risk. DESIGN: A cohort study was performed using the Dutch MEN1 database, including >90% of the Dutch MEN1 population >16 years of age (n = 393). RESULTS: Fifty-eight MEN1 families were identified, of whom 57 were index cases and 247 were non-index cases (n = 304). The median lag time in MEN1 diagnosis of family members was 3.5 (range, 0-30) years. At the time of MEN1 diagnosis, 30 (12.1%) non-index cases had a duodenopancreatic neuroendocrine tumor, of whom 20% had metastases with a mean lag time of 10.9 years, in comparison with 7.1 years without metastases. Twenty-five (10.1%) non-index cases had a pituitary tumor, of whom 80% had a microadenoma and 20% had a macroadenoma, with mean lag times of 7.2 and 10.6 years, respectively. Ninety-five (38.4%) non-index cases had a primary hyperparathyroidism with a mean lag time of 9.5 years in comparison with seven patients without a primary hyperparathyroidism with a mean lag time of 3 years (P = .005). Ten non-index cases died because of a MEN1-related cause that developed during or before the lag time. CONCLUSION: There is a clinically relevant delay in MEN1 diagnosis in families because of a lag time between the diagnosis of an index case and the rest of the family. More emphasis should be placed on the conduct of proper counseling and genetic testing in all eligible family members.

Bronchopulmonary Neuroendocrine Neoplasms and Their Precursor Lesions in Multiple Endocrine Neoplasia Type 1.

OBJECTIVE: The prevalence and clinical behavior of bronchopulmonary neuroendocrine tumors (bNET) associated with multiple endocrine neoplasia type 1 (MEN1) are not well defined. This study aimed to determine the prevalence, potential precursor lesions and prognosis of bNET in patients with MEN1. METHODS: A database of 75 prospectively collected MEN1 cases was retrospectively analyzed for bNET. Patient characteristics, imaging and treatment were evaluated. Resection specimens of operated patients were reassessed by two specialized pathologists. Available CT scans of the whole cohort were reviewed to determine the prevalence of bronchopulmonary nodules. RESULTS: Five of the 75 MEN1 patients (6.6%; 2 male, 3 female) developed histologically confirmed bNET after a median follow-up of 134 months. The median age at diagnosis of bNET was 47 years (range 31-67), and all patients were asymptomatic. Four patients underwent anatomic lung resections with lymphadenectomy; the remaining patient with multiple lesions had only a wedge resection of the largest bNET. Tumor sizes ranged from 7 to 32 mm in diameter, and all bNET were well differentiated. Two patients had lymph node metastases. Two of 4 reevaluated resection specimens revealed multifocal bNET, and 3 specimens showed tumorlets (up to 3) associated with multifocal areas of a neuroendocrine cell hyperplasia within the subsegmental bronchi. One bNET-related death (1.3%) occurred during long-term follow-up. Review of the available CT scans of the patients without proven bNET revealed small bronchopulmonary lesions (≥3 mm) in 16 of 53 cases (30.2%). CONCLUSIONS: bNET in MEN1 might be more common than previously recognized. Their natural course seems to be rather benign. Multifocal tumorlets and multifocal neuroendocrine cell hyperplasia might represent their precursor lesions.

Thymic and Bronchial Carcinoid Tumors in Multiple Endocrine Neoplasia Type 1: The Mayo Clinic Experience from 1977 to 2013.

The clinical features of thymic carcinoid (TC) and bronchial carcinoid (BC) tumors as part of multiple endocrine neoplasia type 1 (MEN1) have been rarely described and their importance in clinical practice is debated. The objective of this study was to describe the clinical presentation and outcome of this uncommon manifestation of MEN1 in a tertiary care center setting. We present the clinical features of patients with MEN1 and either TC or BC evaluated at the Mayo Clinic from 1977 to 2013. A total of 348 patients with MEN1 were evaluated and the prevalence of TC was 2.0% (n = 7) and of BC 4.9% (n = 17). The majority of the patients with BC were men (61%) diagnosed on routine screening (77%) and BC was not the confirmed cause of death in any patient. In contrast, TC patients were all men and during follow-up 43% died due to TC complications. We conclude that TC and BC tumors are uncommon, but important components of MEN1. BC were most commonly diagnosed during routine screening and associated with an indolent course. TC were predominantly seen in men and associated with a more aggressive behavior.