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About chemotherapy

Chemotherapy uses anti cancer (cytotoxic) drugs to destroy cancer cells. The drugs circulate throughout the body in the bloodstream.

Types of chemotherapy

The most commonly used chemotherapy drugs for hairy cell leukaemia are cladribine or pentostatin. 

Cladribine (CDA)

You might have cladribine as an injection just below the skin every day for 5 days in a row.

Some people have cladribine into a vein as a continuous drip (infusion) for 7 days.

There are other ways of having cladribine, including as an infusion over 2 hours for 5 days, or once a week for 6 weeks. Your doctor will talk to you about how you will have it. 

Most people have just one course of cladribine.


You have pentostatin into a vein every 2 weeks, until all signs of the leukaemia have gone or it is under control. The length of treatment varies from one person to another and depends on how the hairy cell leukaemia responds.

Generally the treatment lasts between 3 to 6 months. Each treatment takes around half an hour.

How you have it

You might have chemotherapy as an injection under your skin (subcutaneous injection), or as a drip into your bloodstream (infusion).

Injection under the skin

You usually have subcutaneous injections into the stomach, thigh or top of your arm.

The video below shows you how to give an injection just under your skin. 

Into your bloodstream

You have the treatment through a drip into your arm. A nurse puts a small tube (a cannula) into one of your veins and connects the drip to it.

Diagram of chemotherapy into the bloodstream

You might need a central line. This is a long plastic tube that gives the drugs into a large vein, either in your chest or through a vein in your arm. It stays in while you’re having treatment, which may be for a few months.

Where you have chemotherapy

If you have cladribine as an injection under your skin, you might go to the hospital day unit for your injections. Or a district nurse can give them to you at home.

Your nurse might teach you to give them yourself.

If you have chemotherapy as a drip into your bloodstream, you usually have this in hospital. You might have this as an inpatient on the ward, or as an outpatient in the cancer day clinic.

Before you start chemotherapy

COVID swab test

Due to coronavirus, you need to have a test to check for coronavirus before you have treatment. The test is called a COVID swab test.

To have the test your nurse takes a sample from the inside of your nose and the back of your throat. They use a long cotton bud to take the sample. Or the sample might be saliva or other fluid. Depending on which test your hospital uses, it can take from 90 minutes to a few days to get a result.

At most hospitals, you have a COVID swab test 48 to 72 hours (up to 3 days) before going for your treatment in the chemotherapy unit.

This means you might have the swab test on the same day that you visit the hospital for blood tests and your doctor’s clinic appointment. If you have treatment weekly or more often, some hospitals will ask you to have the swab test on the day of treatment.

Check with your team about when you’ll have the test as there are some differences between hospitals.

Blood tests

You need to have blood tests to make sure it’s safe to start treatment. You have these either a few days before or on the day you start treatment. You have blood tests before each round or cycle of treatment.

Side effects

Common side effects include:

  • increased risk of infections
  • feeling very tired (fatigue)
  • bleeding and bruising easily
  • feeling or being sick (nausea and vomiting)
  • a skin rash
Contact the doctor or nurse immediately if you have any signs of infection such as a temperature below 36C or higher than 37.5C, or you are generally feeling unwell. Infections can make you very unwell very quickly.

Side effects depend on:

  • which drug you have
  • how much of the drug you have
  • how you react

Tell your treatment team about any side effects that you have.

When you go home

Chemotherapy for hairy cell leukaemia can be difficult to cope with. Tell your doctor or nurse about any problems or side effects that you have. Your nurse will give you telephone numbers to call if you have any problems at home.

If you have any questions about chemotherapy for hairy cell leukaemia, you can call Cancer Research UK's information nurses on freephone 0808 800 4040, 9am to 5pm, Monday to Friday.
Last reviewed: 
17 Nov 2020
Next review due: 
17 Nov 2023
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    Accessed November 2020

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    T Robak and others 

    Annals of oncology, Volume 26, Supplement 5, pages 100-107 

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