Also Known As:

  • ET
  • Essential Thrombocythemia
  • Essential Thrombocytosis
  • Primary Thrombocytosis

Why is RareCan interested in Essential Thrombocythaemia?

RareCan is working to accelerate research into Essential Thrombocythaemia by making it easier for researchers to connect with people who have this rare and chronic form of cancer. You can help us do this by becoming a RareCan member and sharing information with us about your diagnosis. We will then get in touch with you about any research opportunities that might be suitable for you.



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What is Essential Thrombocythaemia (ET)?

Essential Thrombocythaemia is a rare and chronic blood cancer where the body produces too many platelets in the bone marrow.

In rare cases, it can develop into Acute Myeloid Leukaemia or Myelofibrosis

How rare is Essential Thrombocythaemia?

The number of people diagnosed each year with ET will be between 1.5 and three cases per 100,000. 

Who does Essential Thrombocythaemia affect?

Essential Thrombocythaemia mainly affects people over the age of 60 but can occur at any age. It is more common in women than men with two women diagnosed for every man.

Essential Thrombocythaemia can develop into other cancers

For some people, Essential Thrombocythaemia can lead to scarring of the bone marrow. This is called Myelofibrosis.

In rare cases, ET can develop into Acute Myeloid Leukaemia (AML), although this happens in less than 5% of people who have ET.

Useful Links:

If you have Essential Thrombocythaemia/Essential Thrombocytosis/Other Name 2/Primary Thrombocytosis and are looking for support, we recommend the following websites:

Blood Cancer UK

Blood Cancer UK is a community dedicated to funding research and support for those affected by blood cancers like ET.

Leukaemia Care Logo

Leukaemia Care is a UK-based charity dedicated to giving information, advice and support to anyone affected by blood cancer.

Opportunities for Members with Essential Thrombocythaemia


The RareCan BioResource

Donating your samples for medical research

Joining RareCan gives you the ability to donate your tissue samples to the BioResource for medical research. Please note that signing up to RareCan does not commit you to donating tissue and you can cancel your membership at any time. If you have Essential Thrombocythaemia and would like to find out more, please click the button below.

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If you’re a friend or family member of someone with cancer, a nurse, an oncologist, an activist, a fundraiser or you’d simply like to help, please start here.

I'm a researcher

If you are interested in setting up a research project or clinical trial aimed at improving the care people affected by rare cancer receive please start here.