Mixed phenotype acute leukaemia (MPAL)

• This accounts for approximately 15% to 20% of all MPAL cases.
• It requires aggressive treatment.

• This accounts for approximately 10% to 20% of all MPAL cases.

• This features a specific genetic mutation called the Philadelphia chromosome.
• It makes up approximately 15% to 20% of all MPAL cases.

• It accounts for approximately 5% to 10% of all MPAL cases.

• This type is more common in children.
• It makes up approximately 20% of all MPAL cases.

• It accounts for less than 5% of all MPAL cases.

A bone marrow biopsy is an important test for diagnosing MPAL.

During the procedure, a needle is used to take a sample of bone marrow, usually from the back of your hip. This spot is easy to reach because the bone is close to the skin. A small amount of liquid bone marrow is removed and sent to the laboratory for testing. Often, a tiny piece of the bone is also taken to be examined.

You will also have bone marrow biopsies to see how you are responding to treatment.

Genetic tests look for changes in cancer cells called mutations. They look for mutations that help to identify the different types of MPAL mentioned previously.

Genetic tests are done on your blood and bone marrow. You don’t need an extra test.

Your haematologist will look at these test results to guide your treatment and estimate a prognosis.

Other tests you may have include:

• medical history and physical exam
• blood tests including full blood count (FBC), kidney and liver function, electrolytes
• computed tomography (CT) scan
• lumbar puncture
• magnetic resonance imaging (MRI).

These tests help your treatment team work out your stage and prognosis.

Remission induction therapy

Remission induction therapy is the first phase of treatment. The aim is to put the leukaemia into remission by destroying the leukaemia cells in the blood and bone marrow.

Central nervous system (CNS) directed therapy

Sometimes the brain and spinal cord (also known as the CNS), can be affected by MPAL. CNS directed therapy is usually given during remission induction therapy. It helps treat or stop cancer from spreading to the brain, spinal cord or the fluid around them.

Consolidation therapy

Consolidation therapy is the second phase of treatment and begins once you are in remission. The aim of consolidation is to mop up any leukaemia cells that are hiding. This is given to lessen the chance of the leukaemia coming back (known as relapse).

Maintenance therapy

Maintenance therapy is the last phase of treatment which lasts about 2 to 3 years. It usually includes taking anticancer medicine by mouth and getting intravenous (IV) treatments at a clinic. You usually don’t need to stay in the hospital during this time.

Chemotherapy (often called chemo) is a common treatment for MPAL. Chemotherapy kills cancer cells and stops them from growing. It also damages healthy cells and causes side effects.

The chemotherapy recommended will depend on your type of MPAL. Often, it is a treatment that is used for ALL or AML. The treatment will also depend on the treatment goal, your age and medical history. Chemotherapy can be given in combination with targeted therapy. 

Treatment plans are shortened to letters like FLAG-Ida. The letters represent the name of the medicines in that plan. Your haematologist will provide you with information on your plan, including when and how often you will have it. 

There are several treatment plans for ALL and AML. They can be found on the Cancer Institute NSW website.

Immunotherapy is a type of biological therapy. It uses the immune system to recognise cancer cells and destroy them. Your treatment team will give this to you via a drip into a vein (intravenous).

Immunotherapy works by:

• stimulating the immune system to find and attack cancer cells
• removing barriers that are stopping the immune system destroying cancer cells.

Monoclonal antibodies are a type of immunotherapy.

Blinatumomab is a monoclonal antibody used to treat some types of MPAL. It works by targeting  the CD19 protein on some leukaemic cells so the immune system can destroy that cell and help control cancer.  

Targeted therapy is a cancer treatment that finds and blocks the parts of cancer cells that help them grow and spread.

Tyrosine kinase inhibitors (TKIs) are a type of targeted therapy known as cancer growth inhibitors. TKIs are usually given with chemotherapy or immunotherapy to treat MPAL with BCR-ABL1 fusion gene. They block the tyrosine kinases (proteins) that the cells use to signal each other to grow. This stops the cancer cells from growing.

Some examples of TKIs include imatinib, dasatinib, and nilotinib.

A bone marrow or blood stem cell transplant is a treatment that restores stem cells after high-dose chemotherapy. Your treatment team might suggest you have a transplant for your MPAL. There are 2 types of transplants:

• An autologous stem cell transplant is when your own stem cells are collected and then given back to you after you have high-dose chemotherapy.
• An allogeneic stem cell transplant is when you receive stem cells from a donor, often a blood relative.

Allogeneic stem cell transplant for eligible MPAL patients is often considered for consolidation therapy.

Clinical trials may be available for MPAL. They often compare new or combination therapies with current treatments, including side effects.

Many are randomised, meaning some patients receive the new treatment, and others receive standard care. Trials help improve future treatments and may offer access to costly new therapies not yet on the Pharmaceutical Benefits Scheme (PBS) in Australia.

If you are considering a clinical trial, your doctor will explain:

• the possible risks and benefits
• how it compares to standard treatment
• what is involved.

You will need to give informed consent before taking part.

Trials are voluntary and run through hospitals and clinics.