About Blood Cancer

In this section you can find out more about:

This will help to give you a better understanding of the disease. Remember, if you want to know more or you have further questions, note them down and speak to your medical professional.

What is Blood Cancer?

Blood Cancers are different to other sorts of cancers which usually develop as a tumour. There’s no tumour with blood cancer – instead the cancer cells circulate in the body through the blood stream.

Most blood cancers develop in the bone marrow when blood cells are in a process called haematopoiesis (see graphic below). Specialised stem cells in bone marrow called haematopoietic stem cells are the starting point for all the different types of blood cells:

  • Red blood cells – that carry oxygen to the cells in our body
  • White blood cells – that fight infection
  • Platelets – that help blood to clot and stop bleeding.

Different types of blood cells form in bone marrow from stem cells

Bone Marrow

Different types of blood cells form in bone marrow from stem cells

A blood cancer occurs when one of the cells on the path to becoming a blood cell develops a mutation and starts growing out of control, forming numerous other abnormal cells that spill out into the bloodstream. They also interfere with the bone marrow’s ability to produce other healthy blood cells. The abnormal blood cells don’t perform their functions properly and may interfere with how normal blood cells function, so people with blood cancer are at risk of infections and bleeding.

There are Three Main Types of Blood Cancer:

  • Leukaemia: This occurs when white blood cells called leukocytes develop in an abnormal way.
  • Lymphoma: This occurs when white blood cells called lymphocytes develop in an abnormal way. These tend to collect in the lymph nodes and other tissues.
  • Myeloma: This is caused by the production of abnormal plasma cells. Plasma cells are a type of white blood cell that produce antibodies to fight infection.

There are a number of different types of leukaemia and lymphoma. The most common sub-types are:


Acute Lymphoblastic Leukaemia (ALL)

More common in children but may occur in adolescents and adults.

Acute Myeloid Leukaemia (AML)

A rare type of leukemia that commonly occurs in adults, but can also affect children.

Chronic Lymphocytic Leukaemia (CLL)

The most common leukaemia in New Zealand with about 120 people diagnosed each year.1 Commonly occurs in adults.

Chronic Myeloid Leukaemia (CML)

CML is a rare cancer with about 70 a year. It occurs mostly in adults over 60 years.


Hodgkin’s disease

This occurs in about 100 people each year in New Zealand.2 Typically affects adolescents and young adults but also older adults (55-70 years).

Non-Hodgkin’s Lymphoma (NHL)

About 740 people each year will be diagnosed with this form of the disease in New Zealand.2 More common in older people (over the age of 50).3

Who gets Blood Cancer?

Blood cancer is the fifth most common cancer in New Zealand.2 Each year around 2,100 New Zealanders will be diagnosed with the disease.1 Lymphomas are more common with around 750 people diagnosed each year, followed by leukaemias (600 diagnosed each year) and myelomas (360 per year).2

Both adults and children can get blood cancer. Children are more likely to get certain forms of leukaemia.1

The most common form of leukaemia, CLL, is rare in younger people and tends to affect those over the age of 60. Other risk factors for CLL include:

  • Being of European descent
  • Being male
  • Having a family history of the disease.

The most common form of lymphoma, NHL affects people of all ages although it is more common in people over the age of 50. Risk factors for NHL include:

  • People with chronic infections or autoimmune conditions, such as coeliac disease, rheumatoid arthritis of systemic lupus erythematosus
  • People who have received long courses of chemotherapy for other forms of cancer
  • People with inherited immunodeficiency or conditions such as HIV/AIDs

These are general risk factors only and they do not necessarily mean that you will have blood cancer. Check with your doctor if you have any concerns


  1. Ministry of Health. 2014. Cancer: New registrations and deaths 2011. Wellington: Ministry of Health. Available from: http://www.health.govt.nz/system/files/documents/publications/cancer-new-registrations-deaths-2011-v4sept14.pdf. Accessed April 2015.
  2. Ministry of Health. 2014. Selected Cancers, 2011, 2012 & 2013. Wellington: Ministry of Health. Available from: http://www.health.govt.nz/publication/selected-cancers-2011-2012-2013. Accessed April 2015.