Panmyelosis is usually referred to as acute panmyelosis with myelofibrosis (APMF) or acute myelofibrosis.

Myelofibrosis means there is scar tissue inside the bone marrow instead of normal tissue. This causes panmyelosis, which means that the bone marrow can't produce enough red blood cells, white blood cells or platelets.

APMF is a very rare form of acute myeloid leukaemia (AML). It's a disease that is difficult to diagnose and often develops very quickly.

Blood cells and leukaemia

To understand how and why leukaemia affects you as it does, it helps to know how you make blood cells.

Your body makes blood cells in the bone marrow. The bone marrow is the soft inner part of your bones. You make blood cells in a controlled way, as your body needs them.

All blood cells start as the same type of cell, called a stem cell. This stem cell then develops into:

• myeloid stem cells become white blood cells called monocytes and neutrophils (granulocyte), red blood cells and platelets
• lymphoid stem cells, which become white blood cells called lymphocytes

The diagram below helps to explain this.

In acute myeloid leukaemia, the bone marrow makes too many monocytes or granulocytes. These cells are not fully developed and are not able to work normally.

In other types of leukaemia, usually only one type of myeloid cell becomes cancerous. But in APMF more than one type of myeloid cell is abnormal. Usually, cells called megakaryocytes are also abnormal in APMF.

Megakaryocytes are the cells that go on to become platelets. So it is sometimes confused with a type of leukaemia called acute megakaryoblastic leukaemia.

Diagnosis

In APMF, the levels of red blood cells, white blood cells, and platelets are low. This is called pancytopenia. This can cause:

• infections
• tiredness
• bleeding

You are usually referred quickly to a specialist in blood disorders (a haematologist), if you have these symptoms. Your specialist will try to take a sample (biopsy) of the bone marrow. They look at the cells under a microscope to check for leukaemia cells. 

Treatment

APML is very rare and there is no standard treatment. Most specialists are likely to treat it in the same way as other types of acute myeloid leukaemia (AML). Often symptoms become worse very quickly. 

Doctors might use chemotherapy, but this can have severe side effects. For example, the treatment can temporarily reduce someone’s ability to fight infection even more than the leukaemia does. So it is possible that patients can have life threatening infections.

Coping

Coping with a diagnosis of a more aggressive cancer can be especially difficult, both practically and emotionally. Being well informed about your cancer and its treatment can make it easier to make decisions and cope with what happens.

Talking to other people who have the same thing can also help.

Our discussion forum Cancer Chat is a place for anyone affected by cancer. You can share experiences, stories and information with other people who know what you are going through.

The Rare Cancer Alliance offer support and information to people affected by rare cancers.