Blood cancer: ask the researcher

Dr Catherine Carmichael answers frequently asked questions about blood cancer.

Dr Carmichael is a molecular cancer biologist and Head of the Leukaemia Modelling and Therapeutic Discovery Research group within the Centre for Cancer Research at Hudson Institute. As a molecular cancer biologist, her research focuses on identifying key molecular mechanisms driving Acute Leukaemia development, with a view to developing new forms of treatment for blood cancers.

Tell us about your research

My research focuses on understanding how aggressive forms of blood cancer, such as AML, develop. Through understanding how blood cancer cells arise, survive and function, as well as how they differ from normal blood cells, we aim to identify and develop new ways to specifically and effectively eradicate blood cancer cells.

What is blood cancer?

Blood cancers arise when blood cells start to grow abnormally and uncontrollably. These abnormal blood cells usually arise in the bone marrow and continue to grow and expand until they fill up the bone marrow and impair its ability to generate normal blood cells.

What are the symptoms of blood cancer?

Common symptoms of blood cancer result from the bone marrow’s inability to generate normal blood cells. For example, loss of red blood cell production leads to anaemia and tiredness, reduced platelet counts can cause increased bruising and bleeding, while reduced production of immune cells can result in frequent infections. Other symptoms may include unexplained weight loss, abnormal lumps or swelling and drenching night sweats.

How common are blood cancers?

Blood cancers represent the second most frequent cancer diagnosis in Australia, and the second highest cancer related cause of death. It is predicted that more than 19,000 Australians will be diagnosed with a blood cancer this year, and sadly nearly 6,000 Australians will die from their blood cancer. (These numbers were calculated from data available at Australian Institute of Health and Welfare.)

Are there different types of blood cancer?

There are several different types of blood cancer that are distinguished by the form of blood cell affected and the way that abnormal blood cell behaves. Some of the more commonly diagnosed blood cancers include leukaemia, lymphoma, myeloproliferative neoplasm, myelodysplastic syndrome and myeloma.

What causes blood cancers and can they be inherited?

It is not known exactly how blood cancers arise, but we know that they are driven by gene mutations that impact normal blood cell development and production. Most blood cancers result from gene mutations that occur in specific blood cells after birth. However, in rare cases some blood cancers can occur due to a gene mutation that was inherited from a parent. In these cases, a person carrying a specific gene mutation has a significantly increased likelihood of developing a blood cancer during their lifetime.

How are blood cancers diagnosed?

Blood cancers are often first suspected following a physical examination and blood test that shows abnormalities in the numbers and/or types of blood cells present. Confirmation of this diagnosis and identification of the exact type of blood cancer usually requires a bone marrow or lymph node biopsy, imaging (such as CT scan, MRI or X-ray) and/or gene mutation analysis.

Can blood cancers be cured/treated?

With the development of new and improved therapies, some blood cancers such as Acute Lymphoblastic Leukaemia (ALL) in children now have very high cure rates above 80 per cent.

Other blood cancers such as aggressive forms of Acute Myeloid Leukaemia (AML), however, can still have as low as a 25 per cent chance of cure with current treatment strategies.

The exact treatment used depends on the type of blood cancer diagnosed. Slow growing blood cancers such as Chronic Lymphocytic Leukaemia (CLL) may not need to be treated during its early stages, with a watch and wait approach utilised. Whereas more aggressive fast-growing blood cancers like AML are often treated with high dose chemotherapy, which aims to kill the rapidly dividing leukaemia cells.

Some gene mutations are sensitive to particular therapies that have been developed to target the specific gene abnormality. These targeted therapies can be used either by themselves or in combination with other treatments like chemotherapy.

Other treatment options include immunotherapy, which encourages a patient’s own immune system to target the blood cancer cells and eradicate them, and radiation therapy, which can be used to treat particular types of blood cancers such as lymphoma or myeloma, or to prepare a patient for a bone marrow transplant.

A bone marrow transplant aims to cure blood cancer by replacing a patient’s abnormal bone marrow with blood stem cells from a healthy donor. These donor blood stem cells are then able to regenerate a normal healthy bone marrow devoid of blood cancer cells.

What does success look like in blood cancer research?

Blood cancers are a leading cause of cancer related death. Some blood cancers can be readily treated and have a high chance of cure, whereas many other types of blood cancers continue to have poor survival rates and lack effective targeted therapies.

Chemotherapy, while very good at killing cancer cells, comes with significant side effects that can impact the quality of life for patients and increase their risk of developing life-threatening infections.

Blood cancers are also very good at adapting to therapeutic pressure and developing resistance to treatment. Success in blood cancer research involves the identification and development of new and more effective ways to treat blood cancers. These new treatments would ideally have significantly reduced side effects, be more effective at specifically targeting blood cancer cells and be less prone to the development of therapy resistance and subsequent disease relapse.