Cancer is the uncontrolled multiplication of our body’s cells. In some cases, the uncontrolled division of cells causes a mass of cells known as a tumour to form. Leukaemia (see entry Leukaemia and other Allied Blood disorders), is a type of cancer where a tumour does not form.

It is important to note that tumours can be malignant (cancerous) and benign (non-cancerous). Benign tumours can sometimes causes problems if they are large and push on surrounding tissues or organs. Malignant tumours have the ability to metastasise, meaning that cancer cells can break off and are able to move from their original location (primary cancer) through the blood and lymph to other areas where a new tumour may form (secondary cancer). Many specific conditions come under the term cancer with over 200 different types.

Cancer is a life-threatening condition, however, the outlook for patients has been greatly altered in recent years due to better detection and treatments.


Medical text written September 2011 by Dr Darren Hargrave, Consultant Paediatric Oncologist, Great Ormond Street Hospital for Children, London, UK.

What are the symptoms?

Cancers can cause different symptoms according to where they are in the body. A tumour may press on a nerve, or another nearby body organ. It may also cause symptoms by releasing chemicals or hormones into the bloodstream.

What are the causes?

Different types of cells in the body do different jobs, but they are basically similar. Nearly all cells have a centre called a nucleus containing genes, which provide instructions that control the cell. They decide when it will multiply producing new copies of itself, what it does and when it will die. Normally genes make sure that cells grow and multiply in an orderly and controlled way, but in cancerous cells there is a change in these instructions and the cells multiply uncontrollably.

How is it diagnosed?

Diagnosis is based on the appearance of symptoms that indicate cancer and will vary between the different types of cancer. Some techniques that may be used for diagnosis include:

  • biopsy − this is where a small amount of tissue is removed from a suspected tumour to see if the cells show characteristics to indicate they are cancerous. In some cases a tumour may be discovered and it is benign (non-cancerous)
  • imaging techniques − these can help identify masses in body tissues, which may be tumours. Computed tomography (CT) and magnetic resonance imaging (MRI) scans allow images of the whole body to be produced on which tumours can be spotted.

There are many other diagnostic tools in use and the types used will vary according to the cancer that is suspected.

How is it treated?

Treatments will vary according to the type of cancer and how far the disease has progressed when it is diagnosed. Some typical treatments are listed below.

In cancer treatment, chemotherapy means treatment with cell killing (cytotoxic) drugs to reduce the cancerous cells. Sometimes a chemotherapy drug is used on its own and sometimes a combination is used.

Radiotherapy means the use of radiation to kill cancerous cell. Radiotherapy can be given outside of the body (external radiotherapy) or inside the body (internal radiotherapy).

Surgery is one of the main treatments for cancer. It can only provide a cure when the cancer that is completely contained in one area and has not spread.

Biological and targeted therapies
Increasingly anti-cancer therapies are available/being developed that target specific abnormal/overactive biological pathways for individual cancer sub-types. These may be in the form of an oral medication or an antibody treatment that is delivered intravenously (into a vein). These biological therapies work by stimulating the body’s (immune system) to attack or control cancer cells.

These include stem cell transplants and bone marrow transplants, which are used to treat Leukaemia and some other cancers. Both transplants help the body to restore its blood cells. In Leukaemia these transplants are used to replace the blood cells that are multiplying out of control. In other cancers, stem cell and bone marrow transplants allow for higher doses of radiotherapy or chemotherapies to be used as it replaces any blood cells that are damaged by treatment.

Inheritance patterns and prenatal diagnosis

Inheritance patterns
The majority of cancers have no inherited component in their cause but some forms of cancer and are associated with inherited conditions.

In recent years, there has been an increase in the knowledge about the genetic causes of cancer. It is now known that there are some types of gene mutations that increase the risk of certain cancers forming in an individual. If these mutations are identified in a person, health professionals can monitor the person carefully for signs of cancer. In families where there is a possibility of an inherited mutation that increases the risk of cancer, genetic advice should be sought.

Prenatal diagnosis

Is there support?

Support Groups for children and families:

Children’s Cancer and Leukaemia Group (CCLG)

Tel: 0333 050 7654

The CCLG is a Registered Charity No. 286669. It is dedicated to supporting the work of those looking after children and younger teenagers with cancer in the UK. The Group provides information and support to families and has a network of specialist centres.

Group details last updatd December 2020.

Kids Cancer Charity (formerly known as Christian Lewis Trust)

Tel: 01792 480500

The Trust is a Registered Charity in England and Wales No. 1113821, established in 1989. It offers a philosophy of child centred care focusing on ‘quality of life’ issues, a range of family support services, bereavement support, self-help support groups, play therapists and holidays.

Group details last reviewed December 2020.

Young Lives vs Cancer (formerly CLIC Sargent)

Tel: 0300 330 0803
Email: via website

The Organisation is a Registered Charity in England and Wales No. 1107328, and in Scotland No. SC039857. It provides information and support to children and young people with cancer, and their families. The Organisation provides clinical, practical and emotional support, and financial support including grants and benefits information.

Group details last updated May 2021.

Teenage Cancer Trust

Tel: 020 7612 0370

The Trust is a Registered Charity in England and Wales No. 1062559. It has 29 units across the UK where teenagers and young adults aged 13-24 who are diagnosed with cancer can be treated together, by teenage cancer experts, in an environment suited to their needs. The Trust provides local support to young people and their families, siblings and partners during and after the young person’s cancer treatment.

Group details last reviewed December 2020.

The Childhood Cancer Parent Alliance (CCPA)

Tel: 01785 283435

The Alliance is a Registered Charity in England and Wales No.1090871, established in 1999. It is an umbrella organisation with almost 40 member groups from around the UK who support children and young adults with cancer and their families. The Alliance acts as a ‘voice’ for the families of children and young people with cancer advising charities and medical bodies on the needs of those affected by such a diagnosis, advocates for better facilities at treatment centres and helps to set up parent-run support groups.

Group details last reviewed December 2020.

Support Groups for adults:

Macmillan Cancer Support

Helpline: 0808 808 0000
Email: via website

Macmillan Cancer Support is a Registered Charity in England and Wales No. 261017.  It provides information and support to people affected by cancer, including carers, families and communities. The Charity funds nurses and other specialist health care professionals, and builds cancer care centres.

Group details last reviewed September 2022.

Rarer Cancers Foundation

Email: via website

The Foundation is a Registered Charity in England and Wales No. 1109213. It provides information and support to anyone affected by any of the rarer cancers. A cancer may be classed as rarer either because it affects an unusual site in the body, or because the cancer itself is of an unusual type, or requires special treatment. The Foundation hosts an online Rarer Cancers Forum.

Group details last reviewed December 2020.

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