Acute and Chronic Leukaemia, Hodgkin's and non-Hodgkin's Lymphoma, Multiple Myeloma, Myelodysplasia and Aplastic Anaemia
Leukaemia (Acute and Chronic)
Leukaemia is a cancer of white blood cells which are made in the bone marrow and its onset is either very suddenly (Acute) or over some period of time (Chronic).
It occurs when immature white blood cells (blast cells) in the bone marrow grow out of control and continue to divide but never mature, meaning that they can not carry out their usual function, which leads to an increased risk of infection.
When the bone marrow fills with leukaemia cells, there is less room for healthy red cells and platelets. This causes other health problems.
The four main types of leukaemia are:
- acute lymphoblastic leukaemia
- acute myeloid leukaemia
- chronic lymphocytic leukaemia
- chronic myeloid leukaemia
Lymphomas are cancers related to lymphocytes and the lymphatic system. The lymphatic system is connected to the blood system and is also a part of the immune system.
In lymphoma, lymphocytes become abnormal. They grow and multiply uncontrollably and/or don't die. As abnormal lymphocytes replace normal lymphocytes, the immune system becomes less able to fight infections. Lymph nodes also become enlarged, forming tumours. There are many different types of lymphoma.
The two main types of lymphoma are:
- non-Hodgkin's Lymphomas
- Hodgkin's Lymphoma
The difference between non-Hodgkin's lymphomas and Hodgkin's lymphoma is the appearance of the lymphoma under a microscope. Hodgkin's lymphoma contains a cell called Reed Sternberg. This cell is not found in non-Hodgkin's lymphoma.
Multiple Myeloma is a cancer of the blood cells known as plasma cells. When a person has multiple myeloma, too many plasma cells are made. This causes overcrowding in the bone marrow, which prevents adequate numbers of normal blood cells forming.
Myeloma also weakens the immune system and the level of normal antibodies is reduced. From the bone marrow, myeloma may spread into the bone itself. It produces substances that can soften the bones, making them weak and more likely to break (osteoporosis).
When bone is damaged like this, it can cause excess calcium in the body (hypercalcaemia) causing pathological fractures. It can also affect the kidneys so that they cannot filter and clean the blood properly.
Aplastic Anaemia is a syndrome of bone marrow failure where the body can not produce enough blood cells, requiring patients to have long term blood transfusion support.
It can be inherited or acquired and can occur as a result from exposure to chemicals or viruses but often the cause is unknown.
Aplastic anaemia is not a type of cancer but a small number of patients with this condition may go on to develop leukaemia.
For more information go to www.leukaemia.org.au