(Multiple endocrine adenomatosis type I, Wermer syndrome)

The multiple endocrine neoplasia type 1 (MEN 1) is a hereditary disease, which is characterized by tumors of the parathyroid glands, the islet cells of the pancreas, and the pituitary. Duodenal gastrinomas, carcinoid tumors of the foregut, benign adrenal adenomas and lipomas may also occur. The clinical signs usually include hyperparathyroidism and asymptomatic hypercalcemia. Genetic screening is performed to identify the carriers of the mutation. Diagnosis is made by hormonal tests and imaging procedures. The tumors are, if possible, surgically removed.

MEN 1 is probably caused by a mutation inactivating the gene encoding the nuclear protein menin; > 500 mutations of this gene have been identified. The exact function of Menin is unknown, but it seems to have tumor-suppressive effects.

The multiple endocrine neoplasia type 1 (MEN 1) is a hereditary disease, which is characterized by tumors of the parathyroid glands, the islet cells of the pancreas, and the pituitary. Duodenal gastrinomas, carcinoid tumors of the foregut, benign adrenal adenomas and lipomas may also occur. The clinical signs usually include hyperparathyroidism and asymptomatic hypercalcemia. Genetic screening is performed to identify the carriers of the mutation. Diagnosis is made by hormonal tests and imaging procedures. The tumors are, if possible, surgically removed. MEN 1 is probably caused by a mutation inactivating the gene encoding the nuclear protein menin; > 500 mutations of this gene have been identified. The exact function of Menin is unknown, but it seems to have tumor-suppressive effects. Approximately 40% of MEN-1 cases show tumors in all three affected gland the parathyroid glands, the pancreas and the pituitary gland. Almost any combination of tumors and symptoms complexes, which will be described later, is possible. A patient with a MEN-1 gene mutation and one of the MEN-1 tumors has a risk of developing in the course of any other possible tumors. The age at onset of the disease is between 4 and 81 years, but has a peak age between 20 and 40 years. Men and women are equally affected. Symptoms and signs The clinical symptoms depend on the affected glands (see Table: Findings associated with MEN syndromes). Parathyroid Hyperparathyroidism occurs in ? 95% of patients before. Asymptomatic hypercalcemia is the most common manifestation, but about 25% of patients have a nephrolithiasis or nephrocalcinosis. In contrast to the sporadic hyperparathyroidism is a diffuse hyperplasia, which is often asymmetrical, the rule here. Pancreatic islet cell tumors of the pancreas occur in 30-90% of patients. Tumors are multicentric in general and sometimes synthesize several hormones. Multiple adenomas or diffuse Inselzellhyperplasie occur frequently; Such tumors are more likely to arise from the small intestine instead of the pancreas. About 30% of tumors are malignant and have metastasized locally or into the distance. Malignant islet cell tumors on the floor of MEN-1 syndrome are usually somewhat less aggressive in its course as a sporadically occurring malignant islet cell tumors. The most common functional enteropankreatische tumor in MEN 1 is the gastrinoma that may arise from the pancreas or duodenum. Up to 80% of patients with MEN 1 have either a plurality of stomach ulcers by a gastrinstimlulierte increased secretion of gastric acid or asymptomatic increased gastrin. Insulinomas are the second most common functional pancreatic tumor and accelerate hypoglycaemia. The tumors are often small and diverse. The age of onset is often <40 years. Functionally inactive enteropankreatische tumors occur in about one third of the MEN-1 patients. Most islet cell tumors, including functionally inactive tumors secrete pancreatic polypeptide. Although the clinical significance is not known, pancreatic polypeptide may be useful for screening. The size of the functionally inactive tumor correlated with the risk of metastasis and death. Less commonly, other functional enteropankreatische tumors in MEN 1 can occur. It may develop a severe secretory diarrhea that may in case of non-?-cell tumors cause a fluid and electrolyte deficiency. This symptom complex, which is also called aqueous Diarrhoe-, Hypokaliämie- and achlorhydria syndrome (WDHA or pancreatic cholera VIPom) is attributed to the effect of vasoactive intestinal polypeptide (VIP), although other intestinal hormones and substances secretagogues (including prostaglandins) probably with helping. Non-?-cell tumors sometimes cause hypersecretion of glucagon, somatostatin, chromogranin or calcitonin, an ectopic secretion of ACTH or "corticotropin-releasing hormone" (caused Cushing's syndrome) and a hypersecretion of "Growth-hormone-releasability hormone "(caused acromegaly) .Hypophyse pituitary tumors occur in 15-42% of the MEN-1 patients. Of which between 25-90% are prolactinomas. About 25% of pituitary tumors secrete growth hormone or growth hormone and prolactin. Excessive prolactin can cause in affected women and excess growth hormones cause acromegaly, which is clinically indistinguishable from sporadic acromegaly Galactorrhoe (galactorrhoea). An ACTH production occurs in about 3% of the tumors and causes Cushing's disease. Most of the remaining tumors are inactive. The local tumor spread can cause blurred vision, headache, and hypopituitarism. Pituitary tumors appear to be larger and to behave aggressively and can at an earlier age than sporadic pituitary tumors auftreten.Andere manifestations carcinoid tumors, especially from embryological precursor cells of the intestine in patients with MEN 1, occur in 5-15% of MEN 1 patients. Carcinoid of the thymus are more common in affected males. Adrenal adenomas occur in 10-20% of patients and may be bilateral. An adenomatous hyperplasia of the thyroid gland occasionally occurs in patients with MEN-1 syndrome. The hormone is in the course rarely increased, and the clinical significance of the changes is unclear. Multiple subcutaneous and visceral lipomas, angiofibroma, meningiomas and ependymomas Kollagenome may also occur. Lipoma © Springer Science + Business Media var model = {thumbnailUrl: '/-/media/manual/professional/images/498-lipomas-slide-8-springer-high_de.jpg?la=de&thn=0&mw=350' imageUrl: '/-/media/manual/professional/images/498-lipomas-slide-8-springer-high_de.jpg?la=de&thn=0', title: 'lipoma' description: ' u003Ca id = "v37895446 "class = " anchor "" u003e u003c / a u003e u003cdiv class = "" para "" u003e u003cp u003eDieses image shows multiple lipomas on the arms of an adult patient. u003c / p u003e u003c / div u003e 'credits' © Springer Science + Business Media'

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