Acute lymphoblastic leukaemia

Blood cells are made in the bone marrow, the soft tissue inside our bones. Every blood cell grows from a stem cell in the marrow.

There are 2 types of blood stem cell:

• lymphoid stem cells, which make a type of white blood cell called lymphocytes (acute lymphoblastic leukaemia affects the lymphoid stem cells)
• myeloid stem cells, which make red blood cells, platelets and other types of white blood cell

The stem cell divides to make an early blood cell called a blast. Blasts usually stay in the bone marrow until they've fully developed.

Once that happens, they move into your blood and take on different jobs:

• white blood cells help fight and prevent infection
• red blood cells carry oxygen to all the cells in your body
• platelets help the blood to clot and prevent bleeding and bruising

ALL affects lymphoid stem cells, which make blood cells called lymphocytes. Lymphocytes usually fight and prevent infection. There are 2 main types:

• B lymphocytes, or B cells
• T lymphocytes, or T cells

Normally, these lymphoid stem cells make blasts that develop into healthy B or T cells.

In ALL, some of the blast cells are abnormal and don't develop fully. These are the leukaemia cells, and they can't do the job of a normal blood cell. They also fill up the bone marrow, so there's not enough space to make the usual numbers of healthy white blood cells, red blood cells and platelets your body needs.

The levels of these cells in your blood are measured in a test called a full blood count (FBC).

Macmillan Cancer Support have more detailed information about the blood and bone marrow, including what the levels of different blood cells usually are.

There are 2 main types of acute lymphoblastic leukaemia (ALL):

• B-lymphoblastic leukaemia (or B cell leukaemia) is the most common type, and it's the one where the B cell lymphocytes are affected
• T-lymphoblastic leukaemia (or T cell leukaemia) is the type where the T cell lymphocytes are affected

Your doctors do tests to find out more about the leukaemia cells. These tests give information about:

• other genetic changes inside the leukaemia cells
• proteins on the surface of the leukaemia cells

The results of these tests can affect the type of drug treatment you have.

Some people with B cell leukaemia have a subtype called Philadelphia positive ALL (Ph+ ALL). It means tests have found a gene change inside the leukaemia cells, known as the Philadelphia chromosome. The change only affects the leukaemia cells. It isn't inherited, so it can't be passed on to your children.

If you have Ph+ ALL, your treatment will include a drug called a tyrosine kinase inhibitor. This drug targets the abnormal protein that the gene change makes.

Doctors don't know what causes acute lymphoblastic leukaemia (ALL). Research is still going on to find out more.

There are some things, called risk factors, that may raise the risk of developing ALL. Some people may have a change in a gene that makes them more likely to get it. More research is needed to understand this properly.

People with certain genetic conditions have a higher risk of developing acute lymphoblastic leukaemia (ALL). These include:

• Down's syndrome
• Fanconi's anaemia
• Bloom's syndrome
• Ataxia-telangiectasia

ALL doesn't run in families (it's not inherited), so other people in your family are not at increased risk of getting it.

If you are exposed to very high levels of radiation, for example after a nuclear accident, your risk of developing acute lymphoblastic leukaemia (ALL) goes up. Radon is a gas that can seep from the soil into buildings. Even high levels of it are not a risk factor for ALL.

Some people are diagnosed with acute lymphoblastic leukaemia (ALL) after being taken to hospital with symptoms that came on quickly. Others go to see their doctor about their symptoms.

If leukaemia is a possibility, you'll see a haematologist, which is a doctor who specialises in treating blood problems. At the hospital, the haematologist and a specialist nurse will talk to you about the tests you need.

If you think you may be pregnant, tell your doctor. Some tests can harm an unborn baby, so your doctor needs to know to plan your care safely.

To diagnose ALL, your haematologist will test your blood and bone marrow for signs of leukaemia cells. Further tests are done to find out more about those cells.

Tests for ALL include the following.

If you have acute lymphoblastic leukaemia, the doctor will arrange blood tests. These check how many of each type of cell are in your blood (a full blood count) and look for leukaemia cells.

In a bone marrow biopsy, a doctor or nurse takes a small sample of bone marrow, usually from the back of the hip bone (the pelvis). The sample goes to a laboratory, where it's checked for abnormal cells.

Immunophenotyping is a test that looks for specific proteins on the surface of leukaemia cells. In acute lymphoblastic leukaemia, it helps show the type of leukaemia and which type of blood cell (B or T cell) has become abnormal.

The test can also be used to look for very small numbers of leukaemia cells during treatment and at the end of it.

Cytogenetics and molecular tests look for gene changes (mutations) inside the leukaemia cells in acute lymphoblastic leukaemia. One of the things they check for is the Philadelphia chromosome, which is why you may hear the term Ph+ ALL. The tests may include the following.

In G-banding, a sample of genetic material is taken from a leukaemia cell and coloured with a dye that stains the chromosomes. The chromosomes are then looked at under a special microscope.

FISH is a test that looks for specific gene changes in acute lymphoblastic leukaemia that G-banding may not show. It checks about 200 cells.

PRC is a very sensitive test that looks for specific gene changes that can't be seen under a microscope. It checks a million or more cells.

Doctors can also use the test to look for very small amounts of leukaemia during treatment and at the end of it.

After a diagnosis of acute lymphoblastic leukaemia, you may need some further tests, including the following.

Your doctor may ask for a few tests to check your general health. These may include:

• X-rays to check your lungs and heart health
• heart tests like an ECG (echocardiogram)

You may also have blood tests to check how your liver and kidneys are working, or tests for infections, like HIV and hepatitis.

A lumbar puncture is a test that checks whether leukaemia cells have reached the fluid around your brain and spinal cord. The doctor puts a thin needle into your lower spine and draws out a small sample of this fluid. The sample then goes to the laboratory for testing.

If you might need a donor stem cell transplant as part of your treatment for acute lymphoblastic leukaemia, you'll have a blood test to find out your tissue type. The doctors use the result to look for a person whose stem cells will be a suitable match for you (a donor).

A team of specialists will meet to talk about the best treatment for you. This group is called a multidisciplinary team (MDT).

The aim of treatment for acute lymphoblastic leukaemia (ALL) is to get rid of the leukaemia cells as quickly as possible, so your bone marrow can work normally again.

Treatment usually starts as soon as possible after diagnosis. You may have your treatment as part of a clinical trial.

Your doctor will explain the different treatments and their advantages and disadvantages. They'll also talk with you about the things to think about when you make treatment decisions.

Your treatment plan for acute lymphoblastic leukaemia (ALL) depends on:

• the type of ALL
• any gene changes (mutations) in the leukaemia cells
• whether the leukaemia cells produce certain proteins

You usually have treatment in 3 phases:

• induction treatment, to get rid of the leukaemia cells in your blood and bone marrow (remission)
• consolidation treatment, to get rid of any remaining leukaemia cells in areas like the brain or spinal cord
• maintenance treatment, which you take as tablets for 2 to 3 years to help prevent the leukaemia coming back

If you have other health problems, you can have less intensive treatment. It carries less risk of serious side effects and may be easier to cope with.

For your induction treatment, you'll usually have a cannula (a short thin tube) put into a vein.

Before you start consolidation treatment, you'll have a central line or PICC line put in. These are used to give you chemotherapy and other treatments.

Your doctor will tell you whether your treatment for acute lymphoblastic leukaemia could affect your chances of getting pregnant or of making someone pregnant. Some people can have fertility preservation before treatment starts. But the treatment has to begin quickly, so this isn't always possible.

During treatment for acute lymphoblastic leukaemia, you'll have blood tests, and samples of your bone marrow will be taken, to check for leukaemia cells. The results show your doctor how well the treatment is working. They also help your doctor decide what treatment you may need next, so that you have the best chance of a cure.

If your tests show only very small numbers of leukaemia cells (this is called minimal residual disease), or none at all, your doctor will say you are in remission.

Chemotherapy is the main treatment for acute lymphoblastic leukaemia (ALL). It uses anti-cancer (cytotoxic) drugs to destroy the leukaemia cells.

You'll have most of the drugs through your line into a vein (intravenously), and you take others by mouth as tablets.

You'll also have chemotherapy into the fluid around your spine and brain, which is called intrathecal chemotherapy. It's given to prevent leukaemia cells spreading to the spine or brain, or to treat any leukaemia cells that may already be there.

Steroids are a key part of your treatment for acute lymphoblastic leukaemia (ALL). They help destroy the leukaemia cells and make chemotherapy work better.

You'll start taking them a few days before your chemotherapy begins.

Steroids can cause side effects, but these will gradually disappear as the dose is reduced.

Targeted therapy drugs work on something in or around the leukaemia cell that helps it to grow.

If you have Ph + ALL (a type of acute lymphoblastic leukaemia), you'll be given a targeted drug called a tyrosine kinase inhibitor together with chemotherapy.

Other drugs, called monoclonal antibodies, may be used depending on the type of ALL. These are a type of immunotherapy treatment. If you have B cell ALL, you may have a drug called rituximab along with chemotherapy.

A treatment called CAR-T therapy is occasionally used in young people with B cell ALL.

A stem cell transplant using donor stem cells may be done to lower the risk of acute lymphoblastic leukaemia (ALL) coming back, or if ALL comes back.

You have the transplant when you are in remission. Whether you have it depends on:

• the risk of ALL coming back
• whether a donor is available

Acute lymphoblastic leukaemia (ALL) and its treatment cause symptoms and side effects. Your doctor and nurses will monitor these, and they'll give you supportive treatments to prevent or manage them.

Supportive treatments may include having:

• drugs, like antibiotics, antiviral and antifungal drugs, to treat or prevent different types of infections
• a blood transfusion, which is given if your red blood cells are low. It will increase your energy levels and reduce breathlessness
• a platelet transfusion, which is given if your platelets are low. It will reduce your risk of problems with bleeding
• drugs called growth factors, which may be given to encourage the bone marrow to make white blood cells

Macmillan Cancer Support has more information about treating ALL.

Leukaemia and its treatments may leave you feeling too unwell or too tired for sex. If your platelets are low, your doctor may advise you to avoid penetrative sex until they recover.

Changes such as hair loss may also affect how you think and feel about your body (your body image). Usually, these difficulties slowly improve as you recover.

Even if your treatment may cause infertility, it's important to use contraception during treatment and for several months after it.

Macmillan Cancer Support has more information about sex during and after treatment, in its material on looking after yourself during treatment and recovery.

If acute lymphoblastic leukaemia (ALL) comes back after treatment, you may have more chemotherapy. The aim is to get a second remission. Some people may be able to have a stem cell transplant from a donor.

Targeted drugs or immunotherapy drugs may also be used. If you have Ph+ ALL, you'll be offered a different TKI.

Occasionally, CAR-T therapy could be a possible treatment option.

Even if you already live a healthy life, you may choose to make some positive changes after cancer treatment.

Small changes, like eating well and keeping active, can improve your health and wellbeing and support your body as it recovers.