Multiple endocrine neoplasia type 1 (MEN1)

Multiple endocrine neoplasia type 1 (MEN1) is inherited in an autosomal dominant fashion and predisposes to the development of hyperplastic or neoplastic changes in the parathyroid and pituitary glands and the endocrine pancreas, along with numerous other characteristic tumors and features. The management of each entity differs to some degree from their sporadic counterparts, while the lack of a genotype‐phenotype correlation requires lifelong clinical, biochemical and radiological screening for the development of new tumors. While the syndrome itself is relatively rare (a prevalence of 1–10/100 000), it is likely that health‐care practitioners from numerous specialities will occasionally encounter a patient with MEN1 and therefore a basic knowledge of the syndrome is important. In addition, many of the associated tumors are seen commonly in sporadic form, and a judicious policy is therefore required in deciding how thoroughly patients who develop these tumors should be screened for MEN1. The current literature on MEN1 is reviewed and key learning points are suggested for the clinician.     

Treatment of the pancreatic disease of multiple endocrine neoplasia type 1 (MEN 1)

This review comprises an analysis of the treatment alternatives for pancreatic tumours of the MEN 1 syndrome presently in use at the Surgical Endocrine Unit of Sahlgrenska Hospital, G?teborg, Sweden. Patients with pancreatic tumours localized by imaging studies are offered surgical excision. Otherwise the therapy is individualized. Some patients with Zollinger-Ellison syndromes are managed with medical antiulcer treatment, others are treated with total gastrectomy. MEN 1 patients with other syndromes, e.g. insulinomas, glucagonomas and VIPomas, are offered surgery with the aim of tumour excision. Even noncurative excision might benefit the management of these cases and possibly prolong life. Asymptomatic patients with raised hormonal tumour markers in whom imaging studies have failed to reveal any tumours, are continuously followed without treatment. The malignant behaviour of the pancreatic tumours varies between different MEN 1 families. MEN 1 patients are considered for total pancreatectomy if they have multiple malignant pancreatic tumours and if the pancreatic disease has caused high morbidity and mortality in the family.     

Quality of life in patients with multiple endocrine neoplasia type 1 (MEN1)

To study quality of life among patients living with a hereditary tumor syndrome, the small group with multiple endocrine neoplasia type 1 (MEN1) was selected. It is characterized by multifocal adenomas of the pancreas, parathyroid, anterior pituitary and other endocrine glands. Patients were assessed at an in-hospital stay and six months later at home. Patients at a specialist ward for MEN1 were recruited consecutively (n = 36) during one year. Eighty-one percent participated (n = 29). Four questionnaires were used: the Hospital Anxiety and Depression Scale (HADS), the Impact of Event Scale (IES), the Life Orientation Test (LOT) and the Short Form-36 (SF-36). Psychosocial outcome measures (anxiety, depression, intrusion, avoidance) changed only marginally between the in hospital stay and six months later at home. However, depression increased for patients categorized as having a high burden of disease and treatment. Compared to population-based norm values, the SF-36 scores of the patient group MEN1were lower for General Health and Social Functioning. Optimism assessed at the hospital was a predictor of Mental Health six months later. Most MEN 1 patients (70%) were pessimists. Patients having a higher burden of disease and treatment are in need of support after discharge. Patients could easily be monitored with questionnaires and, when indicated, offered help for their psychosocial distress.An erratum to this article can be found at     

Surgery for gastrinoma and insulinoma in multiple endocrine neoplasia type 1

The surgical management of pancreatic endocrine tumors in patients with multiple endocrine neoplasia type 1 remains controversial. Gastrinoma and insulinoma are the 2 most common functional pancreatic neuroendocrine tumors in patients with multiple endocrine neoplasia type 1. Gastrinomas cause gastric acid hypersecretion and peptic ulcer disease that are best managed using proton pump inhibitors. Surgery to remove the gastrinoma in patients with multiple endocrine neoplasia type 1 is seldom curative unless a more extensive Whipple pancreaticoduodenectomy is performed. Because the prognosis is excellent, aggressive resections such as a Whipple procedure are only indicated for large, locally metastatic, advanced tumors. Furthermore, surgery to remove imageable tumors that are 2 cm in diameter is associated with excellent outcomes and decreased probability of liver metastases. Because gastrinomas are commonly multiple and most originate in the duodenum and develop lymph node metastases, the duodenum should be opened and all tumors and lymph nodes excised. Insulinomas cause hypoglycemia that results in neuroglycopenic symptoms. Medical management of the hypoglycemia is less effective than that of the gastric acid hypersecretion. Fortunately, the insulinoma is usually clearly identified using routine pancreatic imaging studies. There is a high likelihood of cure when the insulinoma is excised surgically. However, recurrent hypoglycemia may occur, and careful follow-up is indicated.     

A novel germline mutation of the MEN1 gene, L259del, in a patient with sporadic multiple endocrine neoplasia type 1 (MEN1)

A Japanese woman was treated for insulinoma when she was 29 years old. Ten years later, heperparathyroidism and non-functioning adrenal tumor were found and she was diagnosed as having multiple endocrine neoplasia type 1 (MEN1). No other family members have developed MEN-related lesion(s). Genomic DNA of the patient was analyzed by sequencing for the MEN1 gene and a novel, three-base in-frame deletion resulting in deletion of an amino acid Leu259 was identified. Her two children showed a wild-type sequence at this codon.     

Malignant melanoma in patients with multiple endocrine neoplasia type 1 and involvement of the MEN1 gene in sporadic melanoma

Multiple endocrine neoplasia type 1 (MEN 1) is a familial cancer syndrome associated primarily with endocrine tumors of the parathyroids, enteropancreas and anterior pituitary. However, tumors of mesenchymal origin such as angiofibroma and collagenoma of the skin have also been associated with the syndrome. This highlights the possibility of an association between MEN 1 and some other types of tumors. Here we report 7 cases of primary malignant melanoma occurring in 7 MEN 1 families, all patients exhibiting classic features of MEN 1. Based on these findings and the previous implication of multiple melanoma tumor suppressor(s) in 11q, including the MEN1 region, we have investigated the involvement of the MEN1 gene in melanoma tumorigenesis. Mutation analysis was performed on a panel of 39 sporadic metastatic melanomas, 13 melanoma cell lines and 20 melanoma families without CDKN2A or CDK4 germline mutations. In addition, 19 sporadic metastatic tumors were screened for loss of heterozygosity (LOH) in 11q13. LOH was detected in 6 tumors (32%), and in 4 of the tumors the pattern of LOH suggested that the deletion included the MEN1 gene locus. A novel somatic nonsense mutation in exon 7 (Q349X) was identified in 1 sporadic tumor which also showed loss of the wild-type allele. We conclude that the MEN1 gene plays a role in the tumorigenesis of a small subgroup of melanoma.     

A novel germline mutation, 1793delG, of the MEN1 gene underlying multiple endocrine neoplasia type 1

Pulmonary carcinoids are rare neuroendocrine tumors which comprise 1-2% of all lung tumors. They usually occur sporadically; however, their association with multiple endocrine neoplasia type 1 (MEN1) syndrome has been documented. We report a case of a Thai woman with a pulmonary carcinoid tumor and a null cell pituitary tumor. Her family history was unremarkable for any MEN-related lesions. Genetic testing revealed a novel deletion mutation at exon 10 (1793delG) of the MEN1 gene, resulting in a stop codon 26 amino acids downstream. This mutation is predicted to cause a loss of the second nuclear localization signal of the menin protein.     

A whole MEN1 gene deletion flanked by Alu repeats in a family with multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 is an autosomal dominant cancer syndrome characterized by pituitary, parathyroid and enteropancreatic endocrine tumors, which is caused by germline mutations of the tumor suppressor gene MEN1. In the case reported here, the patient had family with this disease whose germline MEN1 mutation was undetectable by conventional sequencing analysis. Further investigations involving polymorphism analyses, gene dose assay and nucleotide sequencing identified a large germline deletion of approximately 29 kilobase pairs spanning the whole MEN1 gene. The deletion was flanked by Alu repetitive sequences, suggesting unequal homologous recombination as the deletion mechanism. The polymorphism linkage data suggested that an asymptomatic son of the proband did not carry the family mutation. More direct evidence was obtained by gene dose assay and deletion-specific polymerase chain reaction, which demonstrated the normal MEN1 gene dosage and the absence of the deletion breakpoints in this asymptomatic subject and thus definitely excluded the possibility of disease predisposition.     

A novel splicing mutation (894-9 G --> A) of the MEN1 gene responsible for multiple endocrine neoplasia type 1.

Germline MEN1 gene mutations are responsible for multiple endocrine neoplasia type 1 (MEN1), a dominantly inherited cancer syndrome. We identified a MEN1 germline mutation 894-9 G --> A in three MEN1 patients from two unrelated families. This mutation was not present in any of the 100 blood samples from normal volunteers. The wild type MEN1 sequence was lost in the patient's pancreatic tumor. Abnormal mRNA was identified in the tumor, which retained an intronic sequence indicating aberrant mRNA splicing at a newly created splicing acceptor site. These findings indicate that this nucleotide substitution is, though previously reported to be a polymorphism, a causative splicing mutation.     

Bronchopulmonary carcinoid in multiple endocrine neoplasia type 1

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal-dominant syndrome associated with neoplasia of pituitary, pancreas, parathyroid, and foregut lineage neuroendocrine tissue. Although enteropancreatic carcinoid has been well described in patients with MEN 1, it was believed that bronchopulmonary carcinoid was relatively uncommon, occurring in approximately 5% of patients. It is unclear whether the increased screening of asymptomatic patients with MEN 1 will facilitate early diagnosis of this tumor and improve patient prognosis. METHODS: The authors reviewed the patient records and, when available, thoracic computed tomographic (CT) images of 129 MEN 1-affected adult members of a single family to determine the prevalence and prognosis of bronchopulmonary nodules and carcinoid. RESULTS: Among 129 patients, a diagnosis of bronchopulmonary carcinoid was noted in the records for 6 individuals (1 male and 5 females; 5%). Thoracic CT scans also were available for review from 32 of those patients. Twelve patients (38%) had pulmonary nodules evident on CT scans. Only hypergastrinemia was significantly more common in patients with pulmonary nodules; otherwise, the spectrum of neoplasia was similar between individuals with and without pulmonary lesions. Histologic diagnoses were available in four patients (three female) with abnormal CT images, and carcinoid was confirmed in each patient. No deaths or distant metastases occurred among the patients despite long-term follow-up (mean, 127 months). CONCLUSIONS: The findings suggested that bronchopulmonary carcinoid is more prevalent in patients with MEN 1 than was recognized previously. Furthermore, the diagnosis did not appear to portend a poor prognosis in the majority of affected patients.     

Type B1 thymoma in multiple endocrine neoplasia type 1 (MEN-1) syndrome.

AIMS AND BACKGROUND: Multiple endocrine neoplasia (MEN) syndromes include a group of disorders characterized by the neoplastic transformation of two or more endocrine tissues. In type 1 syndrome (MEN-1), pituitary, parathyroid and pancreatic islet tumors are most frequently represented. Thymic neoplasms are also rarely associated, and thymectomy during subtotal or total parathyroidectomy should always be considered. STUDY DESIGN: The authors describe a rare case of a 22-year-old male who presented a type B1 thymoma without myasthenia gravis associated to hyperparathyroidism, corticoadrenal adenoma and three neuroendocrine pancreatic lesions (somatostatinoma, glucagonoma and insulinoma).     

Pancreatic insulinomas in multiple endocrine neoplasia, type I knockout mice can develop in the absence of chromosome instability or microsatellite instability

Multiple endocrine neoplasia, type I (MEN1) is an inherited cancer syndrome characterized by tumors arising primarily in endocrine tissues. The responsible gene acts as a tumor suppressor, and tumors in affected heterozygous individuals occur after inactivation of the wild-type allele. Previous studies have shown that Men1 knockout mice develop multiple pancreatic insulinomas, but this occurs many months after loss of both copies of the Men1 gene. These studies imply that loss of Men1 is not alone sufficient for tumor formation and that additional somatic genetic changes are most likely essential for tumorigenesis. The usual expectation is that such mutations would arise either by a chromosomal instability or microsatellite instability mechanism. In a study of more then a dozen such tumors, using the techniques of array-based comparative genomic hybridization, fluorescent in situ hybridization, loss of heterozygosity analysis using multiple microsatellite markers across the genome, and real time PCR to assess DNA copy number, it appears that many of these full-blown clonal adenomas remain remarkably euploid. Furthermore, the loss of the wild-type Men1 allele in heterozygous Men1 mice occurs by loss and reduplication of the entire mutant-bearing chromosome. Thus, the somatic genetic changes that are postulated to lead to tumorigenesis in a mouse model of MEN1 must be unusually subtle, occurring at either the nucleotide level or through epigenetic mechanisms.     

Multiple endocrine neoplasia type 1 presented with manic-depressive disorder: a case report with an identified MEN1 gene mutation

We report a case of multiple endocrine neoplasia type 1 who had repeated hypoglycemic episodes and had previously been diagnosed with bipolar manic-depressive disorder. The patient had a positive family history of multiple endocrine neoplasia type 1 and had multiple pancreatic endocrine tumors, hyperparathyroidism and possibly a pituitary tumor. The pancreatic tumors were resected by subtotal pancreatectomy and examined by histochemical staining and gene analysis. The tumor cells were positive for immunoreactive insulin and glucagon. A microsatellite polymorphism analysis revealed loss of heterozygosity on 11q13 in the tumors. By polymerase chain reaction-based nucleotide sequencing, we identified a germline mutation 483del2 of the MEN1 gene in the normal pancreatic tissue of the patient. This mutation causes a shift of the reading frame of menin mRNA at codon 125. It seems that the wild type allele of the MEN1 gene had been lost in the tumor cells whereas the mutant allele remained intact. This is the first identified MEN1 gene mutation in Japanese families and is different from all MEN1 gene mutations reported previously.      

Metastatic C-cell carcinoma with bone marrow carcinosis in type IIa multiple endocrine neoplasia (MEN). Diagnostic and therapeutic problems

The course of the disease in a patient with multiple endocrine neoplasia type IIa over a period of seven years is described. In spite of multiple diagnostic procedures, only a bone marrow biopsy was able to prove metastatic disease. All therapeutic measures, such as combination chemotherapy, sandostatin, bromocriptine, and 131Iodinemethylendiphosphonate-therapy were not effective in reducing tumor load or symptoms.     

Multiple endocrine neoplasia type 2a (MEN2a): a call for psycho-social research

This paper summarizes what is known about the diagnosis, treatment, and follow-care of people with the inherited disorder multiple endocrine neoplasia type 2a (MEN2a). Several databases were searched throughout the year 2000, including MEDLINE, CINAHL, CancerLit, PsychINFO, and Dissertation Abstracts International. MEN2a is a complex disease involving cancer care and control by surgery, health maintenance, and life-long observation of gene mutation carriers. Genetic testing is the standard of care, prophylactic surgery is recommended during directive counseling, and life-long surveillance is encouraged for people with MEN2a. A substantial body of scientific literature describes morbidity and mortality outcomes of disease treatment, and the monitoring of multiple organ systems. Research is scant concerning the psychological consequences and social impact of the MEN2a diagnosis, treatment, and follow-up. Nearly all that is known from a psycho-social perspective comes from data in The Netherlands. Little is known of the psychological responses to and social consequences of genetic predisposition testing, prophylactic and curative surgery, and life-long surveillance. Psycho-social research is essential to provide comprehensive care for patients and family members with this disorder and it is necessary to guide the development of risk management strategies for patients with this inherited cancer syndrome. Since MEN2a has been labeled a prototype for medical genetics, information on MEN2a patient experiences may be relevant to the care of individuals with other inherited cancer syndromes.     

Broad tumor spectrum in a mouse model of multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN1) is an inherited cancer predisposition syndrome typified by development of tumors in parathyroid, pituitary and endocrine pancreas, as well as less common sites including both endocrine and nonendocrine organs. Deletion or mutation of the tumor suppressor gene MEN1 on chromosome 11 has been identified in many cases of MEN1 as well as in sporadic tumors. The molecular biology of menin, the protein encoded by MEN1, remains poorly understood. Here we describe a mouse model of MEN1 in which tumors were seen in pancreatic islets, pituitary, thyroid and parathyroid, adrenal glands, testes and ovaries. The observed tumor spectrum therefore includes types commonly seen in MEN1 patients and additional types. Pancreatic pathology was most common, evident in over 80% of animals, while other tumor types developed with lower frequency and generally later onset. Tumors of multiple endocrine organs were observed frequently, but progression to carcinoma and metastasis were not evident. Tumors in all sites showed loss of heterozygosity at the Men1 locus, though the frequency in testicular tumors was only 36%, indicating that a different molecular mechanism of tumorigenesis occurs in those Leydig tumors that do not show loss of the normal Men1 allele. Menin expression was below the level of detection in ovary, thyroid and testis, but loss of nuclear menin immunoreactivity was observed uniformly in all pancreatic islet adenomas and in some hyperplastic islet cells, suggesting that complete loss of Men1 is a critical point in islet tumor progression in this model.