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MEN stands for multiple endocrine neoplasia. It is a rare condition that is caused by a faulty gene| that can be passed on within families from one generation to another (inherited). There are two types: MEN1 and MEN2|. Because they have similar names, MEN1 and MEN2 are often confused. In fact, they are completely separate conditions with different genetic causes. MEN1 can't turn into MEN2 and MEN2 can't turn into MEN1.
In multiple endocrine neoplasia, a number of different tumours develop in the endocrine system. The endocrine system is a network of glands in the body. The word neoplasia means new growth or tumour.
MEN1 tumours can be non-cancerous (benign) or cancerous (malignant). Malignant tumours can spread to other parts of the body, but benign tumours do not spread.
MEN1 is diagnosed when a person has more than two endocrine tumours in the body, and is found to have a faulty gene (genetic mutation). A person can also be diagnosed as having MEN1 if they have one endocrine tumour and one or more members of their family have been diagnosed with MEN1.
The endocrine system is made up of endocrine glands. Endocrine glands produce hormones - chemicals that control many of our body's functions. Normally, the hormones released by endocrine glands are carefully balanced to meet the body's needs.
The endocrine glands include the pituitary gland (which lies immediately underneath the brain), the thyroid gland (in the front of the neck), the parathyroid glands (just behind the thyroid gland), and the adrenal glands (on top of the kidneys in the abdomen).
MEN1 is a very rare condition that can affect men or women at any age. Although it tends to be an inherited condition, known as familial MEN1, it can sometimes occur in people who do not have any family members diagnosed with it and it is then known as sporadic MEN1.
If a person has MEN1, they are known as a MEN1 carrier. There is a one in two (50%) chance that they will pass the genetic mutation on to their children.
MEN1 occurs because of an inherited genetic change (mutation). We all inherit our genes from our parents. Genes affect the way your body grows, works, and looks. In people with MEN1 there is a mutation, or mistake, in one gene of every cell. This mutation causes tumours to develop in the endocrine system. It is not known exactly what causes this genetic change, and research is ongoing to try to find out.
Almost all people with MEN1 will develop overactivity of the parathyroid glands, known as hyperparathyroidism, at some stage in their life. This is often shown by an abnormally high level of calcium in the blood (hypercalcaemia). There may be tumours in the parathyroid glands, which are usually benign.
Tumours can also develop in the digestive system (gastrointestinal tract or GI tract), usually in the stomach, intestines and/or pancreas. These tumours can be benign or malignant. Other tumours can develop in the pituitary gland| or the adrenal glands|; these are usually benign.
Rarely, people may develop a particular type of tumour (known as a carcinoid tumour|) in the chest, thymus gland (behind the breast bone), or the gastrointestinal tract.
The symptoms for people with MEN1 can vary according to whether or not tumours develop and where these tumours are. Symptoms often occur because a tumour is causing too many hormones to be produced. The particular symptoms depend on:
The main endocrine tumours, and some of the most common symptoms they cause, are listed below. It is important to remember that these tumours can affect people in different ways, and that the symptoms can be similar to those of many other non-cancerous conditions.
Tumours of the parathyroid gland Possible symptoms include high levels of calcium in the blood (hypercalcaemia), a possible lump or swelling in the neck, muscle weakness, pain| in the bones, vomiting|, loss of appetite|, weight loss, constipation|, difficulty sleeping, lethargy, nervousness, and stomach ulcers.
Tumours of the pituitary gland Symptoms can include headaches and sight problems. Infertility| may occur. Some people have a condition called acromegaly which affects growth, leading to an enlargement of the hands and feet, and can lead to high blood pressure and diabetes. Women may notice that their periods stop, and they may produce small amounts of breast milk. Men may be unable to have an erection (impotence).
There are several different types of GEP tumours| (gastroenteropancreatic tumours). They tend to develop in the organs of the digestive system such as the stomach (gastro), intestines (entero) and the pancreas.
Tumours of the adrenal gland These tend to be 'non-functioning', which means there is not an excess production of hormones and there are no obvious symptoms.
MEN1 is due to an alteration (mutation) in a gene. We all have many thousands of genes. We have two copies of every gene, one inherited from our mother and the other inherited from our father. People with MEN1 have an alteration in one of the copies in their MEN1 gene, and one normal copy of the gene. They can pass on either copy to their children, so there is a one in two (50%) chance that a child of someone with MEN1 will inherit the condition. The chance is the same for each child, regardless of their sex.
It is possible to identify the gene change in an affected person by doing a genetic test|. This involves analysis of the DNA (genetic code) from a blood sample. This can be a time-consuming process which often takes a number of months. In some cases the gene change can't be found although the person is affected with MEN1. This is probably due to technical limitations of the test. Before genetic testing is carried out, counselling is arranged to help people to understand how the test results may affect them individually and as a family.
If a gene change is found, other family members can then be tested to see if they have inherited the same gene change. If they have not inherited the gene change, then they do not need any monitoring. However, if they have inherited it, then they will need to be closely monitored to detect any possible complications at an early stage.
The treatment for MEN1 depends on which tumours have developed, and can involve surgery| to remove the tumours or medicines to help control the symptoms. Although there is no way of changing the genetic mutation, problems caused by MEN1 can often be recognised at an early stage and successfully controlled or treated. Careful monitoring enables your doctor to adjust your treatment as needed and to check for any new problems that the MEN1 may cause.
Research into treatment for MEN1 is ongoing and advances are being made. Doctors use clinical trials| to assess new treatments. Before any trial is allowed to take place, an ethics committee must have approved it and agreed that that the trial is in the interest of the patients.
You may be asked to take part in a clinical trial. Your doctor must discuss the treatment with you so that you have a full understanding of the trial and what it involves. You may decide not to take part, or to withdraw from a trial at any stage. You will then receive the best standard treatment available.
The need for practical and emotional support is, of course, different for each person. Some people with MEN1 may find that their life is largely unaffected, but for others the condition may be a source of great fear and distress.
You may have many different emotions| including anger, resentment, guilt, anxiety and fear. These are all normal reactions, and are part of the process many people go through in trying to come to terms with their condition and its treatment. You don't have to cope with these feelings on your own; people are available to help you. Some hospitals have their own emotional support services with specially trained staff and some of the nurses will have received training in counselling. You may wish to contact our cancer support specialists| for information about counselling in your area.
This section has been compiled using information from a number of reliable sources, including;
For further references, please see the general bibliography|.
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