In each phase of treatment your child will have a combination of several different drugs. The drugs may be given in different ways:
- by mouth (oral) – as a tablet or solution
- into a blood vessel (intravenous or IV) – this may be as a single injection or by a ‘drip’ (infusion)
- into a muscle (intramuscular or IM) – as an injection
- into the fluid around the spine and brain (intrathecal or IT) – as an injection; this type of treatment uses the same procedure as the lumbar puncture.
The following chemotherapy drugs are used in various combinations in treatment for childhood ALL:
- cyclophosphamide – intravenous
- cytarabine – intravenous
- daunorubicin – intravenous
- dexamethasone (a steroid) – tablets or liquid
- vincristine – intravenous
- intrathecal methotrexate – injected into the fluid around the spine and brain
- mercaptopurine – tablets or liquid
- oral methotrexate – tablets or liquid
- pegaspargase/crisantaspase – intramuscular.
Phases of treatment
The total length of treatment is just over two years for girls and just over three years for boys. Treatment length is different for each because it’s been found that if boys stop treatment at two years, it’s more likely that their disease will return (this is known as a relapse).
This section gives an overview of the different phases of treatment. Your healthcare team will explain to you in detail which drugs your child will have and when, and can give you a chart to show this.
The treatment schedule is quite complicated and you’ll need to follow it carefully during the outpatient stages of treatment. If you’re having difficulty making sure your child receives all of the treatment at the right time, talk to your healthcare team – there are a number of different ways they can offer support.
Phase 1: induction
The first phase of treatment is called induction. For the first five weeks of treatment, your child will have intensive chemotherapy treatment to get rid of as many leukaemia cells as possible.
Your child will need to stay in hospital for at least the first week or two because the doctors will need to monitor them closely for any complications from treatment.
The doctors will do further bone marrow tests during and at the end of this first phase to see how your child is responding to the treatment. After two weeks, some children on regimen A will move onto regimen C. This will happen if the results of your child’s cytogenetic tests suggest that they need stronger treatment.
After four weeks, your child will have an MRD test to find out how many leukaemia cells are still in their bone marrow. If there are a low number of leukaemia cells present (this is called MRD low risk), your child will stay on the same treatment (regimen A or B). If there are a higher number of cells (this is called MRD risk), the treatment will move to the stronger regimen C.
Phase 2: consolidation
When the induction phase is complete, your child will have further chemotherapy to clear remaining leukaemia cells from the blood and bone marrow, and also to prevent leukaemia cells from spreading into the brain and spinal cord (the central nervous system or CNS).
For most of this time your child will be able to stay at home and only visit hospital for treatment or checkups (this is known as outpatient treatment). If your child has an infection or becomes ill at any stage during their treatment, they may need to return to hospital to stay in overnight or longer so doctors can monitor them closely.
The length of this phase and the type of chemotherapy your child will have is based on the results of the MRD test at the end of the induction phase.
- If your child is MRD low risk, then consolidation will last for either three weeks (regimen A) or five weeks (regimen B).
- If your child is MRD risk at the end of induction, then they’ll move onto regimen C and consolidation will last for 10 weeks.
- If your child is on regimen B for induction, but the results of their cytogenetic tests during induction suggest that they need stronger treatment, then they’ll move onto regimen C at the start of consolidation.
If your child is MRD risk, your doctors will carry out extra MRD tests halfway through and at the end of consolidation. If these show that the disease isn’t responding to the treatment, then your consultant will talk to you about which alternative treatment options might be most effective.
Phase 3: interim maintenance
For children on regimen A and B, this third phase lasts for about two months and gives a break of less intensive treatment between consolidation and delayed intensification (phase 4). The main treatment during this period will be oral chemotherapy, and your child will be able to stay at home for most of the time.
Children on regimen C will have a more intensive course of chemotherapy involving methotrexate. Your child’s doctor will explain to you exactly how this treatment is given because this will depend on whether your child is taking part in the UKALL 2011 clinical trial or not.
Phase 4: delayed intensification
Delayed intensification will last for seven or eight weeks depending on whether your child is MRD low risk or MRD risk. The aim of this phase is to give intensive chemotherapy at a time when the number of leukaemia cells is very low, to clear as many of them as possible. Your child will mainly be an outpatient for this phase of treatment.
Phase 5: maintenance
This is the longest but gentlest phase of treatment. It lasts for just under two years for girls and just under three years for boys. It reduces the risk of the disease coming back. Your child will mainly be an outpatient for this phase of treatment.
By the time your child has moved onto maintenance therapy they may be well enough to resume their normal activities, including attending school regularly. However, recovery time varies a lot in children and some may take a little longer to get back to their normal activities, even if they’re feeling much better physically – this is normal too.
As well as the phases of treatment described, your child will need care to prevent and treat infections, and to deal with the side effects of treatment.
Preventing and treating infections
If your child gets an infection, they may need intensive treatment with intravenous antibiotics or antifungal drugs. They’ll also take an antibiotic for two days each week throughout their treatment, to reduce the risk of a particular type of pneumonia which can sometimes happen in patients with a weakened immune system.
The drugs used in your child’s treatment will reduce the number of normal blood cells made by their bone marrow. This means they’re likely to need red blood cell transfusions and platelet transfusions at times during their treatment.
Your child will usually have a tube, known as a central line, inserted into a large blood vessel. The central line can be used for taking blood as well as giving treatment and other medicines, and means the doctors won’t have to use a needle each time your child has their treatment.
There are various types of central lines used, and your healthcare team will show you how to care for the central line.
Sometimes a child may find it difficult to eat or drink because of the side effects of chemotherapy. If this is particularly difficult, your child may need to be fed through a tube going directly into their stomach. In this case, your healthcare team will show you how to give feeds and how to care for the tube.