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List of terms beginning with Me

MEK inhibitors

MEK inhibitors are a type of biological therapy cancer treatment. MEK stands for mitogen activated protein kinase. It is a body protein that sends signals to cells telling them to divide and grow. Some drugs block MEK and are called MEK inhibitors. Blocking MEK may stop cancer cells growing.


MEN stands for multiple endocrine neoplasia. It is a rare inherited condition in which two or more tumours develop in the endocrine system. There are several types of MEN and the type you have influences where the tumours develop. MEN is caused by a faulty gene and the genetic fault is different with each type of MEN. The tumours may be benign (non cancerous) or malignant (cancer).


MEN 1 stands for multiple endocrine neoplasia 1. It is a rare inherited condition in which you develop tumours in the endocrine system, most commonly in the parathyroid glands and pituitary gland and the pancreas. But tumours can also develop in the bowel, stomach, or adrenal glands. The tumours can be benign (not cancer) or malignant (cancer). They often produce large amounts of hormones.


MEN 2 stands for multiple endocrine neoplasia 2. It is a rare inherited condition where you develop tumours in the endocrine system. The tumours are most often in the thyroid gland but can also develop in the adrenal glands and occasionally the parathyroid glands.

Meals on wheels

Ready made, cooked midday meals delivered to people in their own homes. The meals can be arranged through social services for people who cannot shop or cook for themselves.


An infectious disease caused by a virus. Measles can be dangerous to people who have low resistance to infection, for instance after chemotherapy. There is a vaccination for measles, but it should NOT be given during chemotherapy treatment as it is a live virus vaccine.


A term used in statistics and trial results. It means the middle number in a series of numbers. For example, if five children are aged 2, 3, 5, 7, and 13, the median age is 5.


An examination of the mediastinum (the central area of the chest). The doctor makes a small cut at the base of the neck and puts a small tube through the cut and into the mediastinum. They can look through this tube to examine the area and also take tissue samples (biopsies) if necessary.


The area at the centre of the chest which contains the heart, windpipe (trachea), food pipe (oesophagus), large main blood vessels and the lymph nodes that surround the heart.

Medical Research Council

The Medical Research Council (MRC) is an independent organisation that funds, plans and oversees medical research trials, including cancer clinical trials.

Medical history

Record of a person's illnesses, allergies, operations and other medical treatments. All doctors ask for this information when they first see a patient.

Medical oncologist

A doctor specialising in the treatment of cancer with chemotherapy, hormone therapy, and biological therapies.

Medical physicist

A specialist in using radiation to diagnose and treat illness. They make sure equipment is accurate and safe, and advise doctors on planning radiotherapy treatment and the best type of test or radiotherapy machine to use.

Medroxyprogesterone acetate (Provera)

A man made form of progesterone (female sex hormone). It is used to treat some types of cancer. It has the brand name Provera.


Medulloblastoma is a type of brain tumour that starts in the area of the brain called the cerebellum. It is the most common type of brain tumour in children. These tumours are part of a group of tumours called primitive neuroectodermal tumours (PNET's) that develop from primitive (poorly developed) nerve cells in the brain.

Megestrol acetate

A man made form of progesterone (female sex hormone). Can be used to treat some types of cancer. It has the brand name Megace.


The substance that gives skin its colour (pigment).


The cells in the innermost layer of the epidermis that make the skin pigment, melanin. Melanin is what gives you a sun tan. These cells become cancerous in malignant melanoma.


A particular type of cancer that usually starts in the skin. It develops from the cells that produce the skin pigment, melanin. It may develop from an existing mole or may appear as a new mole. Very rarely, melanoma can occur in other parts of the body, such as the eye or in an internal body organ. If melanoma is found early, before any cells have spread, it has a very high cure rate.


A type of brain tumour that is usually benign. It develops from the covering of the brain and spinal cord (meninges) and can occur in any part of the brain or spinal cord.

Menopausal effects

Effects of the change of life (menopause), such as hot flushes and sweats, putting on weight, memory changes and feeling anxious. These happen because the body is getting used to lower levels of sex hormones (oestrogen and progesterone).


The change of life. The period of time between the early forties and late fifties when women stop producing sex hormones. Periods become irregular and stop and women can no longer become pregnant.

Menstrual cycle

The monthly cycle of a woman's reproductive system, during which an egg is produced (ovulation). If the egg is not fertilised the lining of the womb is shed as a period. The cycle takes roughly 28 days.


A type of cancer most commonly diagnosed in the sheets of skin like tissue that cover each lung. These are called the pleura, or pleural membranes. Mesothelioma is sometimes also diagnosed in the peritoneum. This is the sheet of tissue that lines the wall of the abdominal cavity and covers the digestive system organs inside the abdomen.

Meta analysis

A meta analysis means taking the results of many trials that have tested the same treatment, and looking at the results all together. This can give a more accurate picture than looking at the results of each trial separately.


Areas that cancer has spread to from the original tumour. For example, areas in the liver where cancer has spread from another part of the body are called liver metastases. They are also called secondaries.


An area of cancer that has spread from the original (primary) tumour. For example, cancer spread to the liver from another part of the body is called liver metastasis. The plural is metastases. Also known as secondary cancer.

Metastatic breast cancer

Breast cancer which has spread to other parts of the body.

Metastatic cancer

Metastatic cancer is cancer that has spread from where it started to other parts of the body.


A chemotherapy drug.

Updated: 29 June 2016