Treatment when hairy cell leukaemia comes back

When hairy cell leukaemia comes back it is called a relapse. You usually have more treatment. This next lot of treatment is called second line treatment.

You might need further treatment if:

  • tests show that your hairy cell leukaemia has not responded to first line treatment
  • hairy cell leukaemia comes back (relapses) after a period of time

You can have a further remission with more treatment. 

Second line treatment is usually chemotherapy again. You might have chemotherapy on its own or combined with a targeted cancer drug.

What treatment will I have?

Most people have chemotherapy as a first treatment for hairy cell leukaemia. You usually have either cladribine or pentostatin.

The second line treatment depends on: 

  • the time since your last treatment
  • what treatment you have already had
  • what clinical trials are available
  • your general health and symptoms

You might have the same chemotherapy drug again. Or you might have a different drug.

This means that if you had cladribine treatment the first time, you might have it again. Or you might have pentostatin as your second line treatment.

You either have chemotherapy on its own, or combined with the targeted cancer drug called rituximab. 

There are other treatment options if you relapse again. These include:

  • a different chemotherapy (such a bendamustine) combined with rituximab
  • clinical trials looking at different targeted drugs

How you have treatment

This depends on which treatment you have.

Treatment can be:

  • an injection under the skin (subcutaneous)
  • an injection into a vein as a drip (intravenously)

Injections under the skin

You usually have injections under the skin (subcutaneous injection) into the stomach, thigh or top of your arm.

You might have stinging or a dull ache for a short time after this type of injection but they don't usually hurt much. The skin in the area may go red and itchy for a while.

Into the blood stream

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.

Clinical trials

Doctors and researchers do trials to make existing treatments better and develop new treatments. As hairy cell leukaemia is rare, there are fewer trials, compared to some types of cancer. There may not always be a trial available or suitable for your situation. But do discuss this with your specialist if you're interested in taking part in a trial.

Doctors often work together across different countries to run trials and share information.

Other treatments

You might have other treatments to treat symptoms of hairy cell leukaemia, or to prevent problems caused by the leukaemia.

Other treatments you might have for CLL include:

  • surgery
  • supportive treatments such as antibiotics or blood products


Surgery is not a common treatment for hairy cell leukaemia. But rarely, the doctor might suggest an operation to remove the spleen (splenectomy).  Removing the spleen can help with some of the symptoms caused by a swollen (enlarged) spleen.

Supportive treatments

Hairy cell leukaemia and its treatment can cause problems. Supportive treatments can help to either prevent or control these problems. Supportive treatments include:

  • preventing and treating infections
  • blood products

Coping with relapse

Hairy cell leukaemia can be difficult to cope with. Knowing that it is going to come back at some point but not knowing when is especially difficult. The time between remission and relapse varies from person to person. Some people have months and others have years. Living with uncertainty is hard. And when it does come back it can feel very difficult even when you have known it will happen.

The type of support people need also varies. Finding what works for you is important. Talking to family and friends helps many people. There is also help and support available from specialist nurses, counsellors and support groups.

Last reviewed: 
16 Aug 2021
Next review due: 
13 Aug 2024
  • Consensus guidelines for the diagnosis and management of patients with classic hairy cell leukemia
    MR Grever and others
    Blood. 2017. Volume 129, issue 5, pages 553 to 560

  • Pan-London Haemato-Oncology Clinical Guidelines Lymphoid Malignancies Part 5: Less Common Lymphoid Malignancies
    London Cancer Alliance (LCA), 2020

  • Hairy cell leukaemia: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up
    T Robak and others on behalf of the ESMO Guidelines Committee
    Annals of Oncology, 2015. Volume 26, supplement 5, pages v100–v107

  • Long-term follow-up after purine analogue therapy in hairy cell leukaemia
    M Else and others 
    Best Practice & Research Clinical Haematology, 2015. Volume 28, pages 217 to 229

  • Current Therapy and New Directions in the Treatment of Hairy Cell Leukemia: A Review
    A Sarvaria and others 
    JAMA Oncology, 2016. Volume 22, No 1, pages 123 to 9

  • Guideline for the diagnosis and management of hairy cell leukaemia (HCL) and hairy cell variant (HCL-V)
    N Parry Jones and others
    British Journal of Haematology 2020, Volume 191, pages 730 – 737

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