Leukaemia and lymphoma – what's the difference?

advertisement
Freephone helpline 0808 808 5555
[email protected]
www.lymphomas.org.uk
Leukaemia and lymphoma –
what’s the difference?
This is a difficult question to answer simply but it is one that is often asked. The aim of
this article is to provide an introduction to this subject, explaining the difference between
leukaemia and lymphoma with respect to:
●
what type of cell they develop from
●
what kinds of leukaemia there are and what kinds of lymphoma there are
●
who gets them
●
the most common symptoms they cause
●
how they are diagnosed
●
how they are treated
●
how they are followed up.
We have included a list of useful organisations that provide more detailed information on
leukaemia and lymphoma and support for people with these conditions at the end of the article.
Where do they come from?
Leukaemia and lymphoma, like other cancers, develop when a group of cells in the body starts
to grow in a way that is out of control. The cells might be dividing too quickly or surviving
longer than their normal lifespan, so they build up in large numbers. The difference between
leukaemia and lymphoma is that leukaemia is a cancer of the blood whereas lymphoma is a
cancer of the lymphatic system (which we will describe below).
What is leukaemia?
Leukaemias are a group of cancers of the blood-forming cells. They start in the bone marrow,
which is spongy tissue that is found in the middle of some of our bigger bones. The abnormal
cells spread from there into the bloodstream and to other parts of the body. The leukaemia is
described as lymphoid or myeloid, depending on which type of blood-forming cell in the
bone marrow the abnormal leukaemia cells develop from.
What is lymphoma?
Lymphomas are cancers of the lymphatic system. The lymphatic system is a complex network
of tubes (lymphatic vessels), glands (lymph nodes) and other organs including the spleen
and thymus gland. Lymph nodes are found in the neck, armpits, groin, chest, abdomen and
pelvis. The vessels and nodes contain a fluid called lymph and special types of cells called
lymphocytes, which help us fight infections. A lymphoma develops when some of your
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
1/7
lymphocytes are out of control. These abnormal cells can build up in lymph nodes, in the bone
marrow or in the spleen and sometimes in other places in the body.
What kinds of leukaemia and lymphoma are there?
Types of leukaemia
Leukaemia that develops quickly is called acute leukaemia and leukaemia that develops
slowly is called chronic leukaemia. The main types are named according to whether they
are acute or chronic and also according to which type of blood-forming cell has become
cancerous. There are four main types of leukaemia:
●
acute lymphoblastic leukaemia (ALL)
●
acute myeloid leukaemia (AML)
●
chronic lymphocytic leukaemia (CLL)
●
chronic myeloid leukaemia (CML).
●
Types of lymphoma
There are many different types of lymphoma but the two main kinds are:
●
●
Hodgkin lymphoma (HL)
non-Hodgkin lymphoma (NHL) – these are then further subdivided into two main types
of NHL, depending on how quickly they are growing, high-grade (or ‘aggressive’) NHLs and
low-grade (or ‘indolent’) NHLs.
A note on chronic lymphocytic leukaemia
There is a type of non-Hodgkin lymphoma called small lymphocytic lymphoma (SLL) which is
considered to be the same disease as chronic lymphocytic leukaemia (CLL) but without the
abnormal cells in the blood. Because CLL and SLL are now considered to be one and the same
condition (their treatment is the same too), CLL is classified as a non-Hodgkin lymphoma.
Who gets leukaemia and lymphoma?
Who gets leukaemia?
In general, the risk of developing leukaemia increases with age, but each type has its own
pattern:
●
●
ALL can occur at any age but it is more common in childhood, especially between the ages
of 2 years and 5 years. The risk also increases again in people aged over 45.
AML is the most common type of acute leukaemia in adults. It becomes more common the
older people get but children and adults can be affected at any age.
●
CLL mainly affects people aged over 50.
●
CML mainly affects adults.
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
2/7
Who gets lymphoma?
●
●
Hodgkin lymphoma is more common in young people aged between 20 and 25 years.
It becomes more common again in later life, with another ‘peak’ at about 75–80 years.
NHL becomes more common with increasing age; around 70% of people with NHL are
aged over 60 when they are diagnosed.
What symptoms do they cause?
The symptoms of blood and lymphatic cancers can be very non-specific and can occur in
more common conditions which are not cancerous.
The symptoms of leukaemia
In leukaemia the bone marrow (where all the blood cells are made) becomes filled with
abnormal cells, leaving little space for the development of normal healthy red cells, white cells
and platelets. The common symptoms of leukaemia happen because you don’t have enough
healthy blood cells:
●
●
●
A lack of red blood cells (anaemia) causes tiredness, reduced ability to exercise and
breathlessness on exertion.
A lack of the white blood cells that normally help us combat infections with bacteria
(neutropenia) leads to an increased risk of developing these infections.
A lack of platelets, which are cell fragments that normally help with blood clotting, leads to
bruising and bleeding, especially from the gums, nose and gut. This shortage of platelets is
called thrombocytopenia.
Other symptoms of leukaemia include fever, night sweats, abdominal discomfort or a feeling of
fullness when eating (due to an enlarged spleen) and enlarged lymph nodes.
The symptoms of lymphoma
In lymphoma, the most common symptoms are:
●
enlarged lymph nodes
●
fever
●
excessive sweating, especially at night
●
unexplained weight loss
●
unusual tiredness
●
abdominal discomfort and fullness when eating, due to an enlarged spleen.
How are leukaemia and lymphoma diagnosed?
Diagnosis of leukaemia
An abnormal blood test result can suggest leukaemia, especially if the person has some of
the symptoms described above. The counts of the different blood cells will be abnormal.
Most people with suspected leukaemia will also need to have a bone marrow biopsy.
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
3/7
This involves injecting local anaesthetic into the skin at the back of the hip and taking a small
sample of the bone marrow from the hipbone using a special needle. This test will be done in
hospital and takes about 20 minutes. Although it is an uncomfortable test to have done, most
people only need a paracetamol painkiller for some dull pain around the hip afterwards.
The bone marrow sample provides a lot of very useful information, which will help your
medical team to decide on the very best treatment for you. The initial results of the test are
normally available within 24 hours, with more detailed results being sent from the lab over the
next couple of weeks.
Diagnosis of lymphoma
Lymphoma is diagnosed by obtaining a biopsy of the affected tissue. A biopsy means taking a
sample from an enlarged lymph node under a local or a general anaesthetic and looking at it
under a microscope. Where possible, the whole lymph node will be removed. X-rays are often
used to help the medical team take the sample from the suspicious gland.
The blood count is less useful in lymphoma than it is in leukaemia. It can be entirely normal or
it can show a low red blood cell count (anaemia); the white cell count and platelet count can
be high, normal or low in lymphoma.
Most people will also need a scan to see if there are enlarged lymph nodes in the chest,
abdomen or pelvis, and a bone marrow biopsy is often done to see if there are lymphoma
cells in the bone marrow. This allows the doctors to determine the stage of the disease. It can
often take up to 2 weeks for all these results to come back.
How are leukaemia and lymphoma treated?
The treatment depends on:
●
what kind of leukaemia or lymphoma you have
●
your age
●
your general health before becoming unwell.
People who develop leukaemia and lymphoma might be given the option of entering a clinical
trial. It is considered advisable (in fact, best practice) for patients to be treated in the context
of a clinical trial, but for a variety of reasons this is not always possible.You will be given plenty
of opportunity to discuss this.
The treatment of leukaemia
Chemotherapy is the first treatment offered for people with acute leukaemia. Most
people with acute leukaemia will be fit enough for intensive treatment and will usually receive
several courses of chemotherapy. This will involve a series of stays in hospital, the first usually
lasting for 4–6 weeks. This is because the chemotherapy destroys both the ‘good’ and the ‘bad’
cells from the bone marrow and it takes about 4 weeks for the good cells to grow back in the
marrow and allow recovery of the blood counts.
Different drugs are used to treat acute myeloid leukaemia and acute lymphoblastic leukaemia.
The number of courses of chemotherapy you need will depend on what kind of leukaemia
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
4/7
you have and your age. Your doctors might discuss the possibility of a bone marrow transplant
with you, although this is not always the best treatment for everyone with acute leukaemia.
Most people with chronic myeloid leukaemia can be treated as an outpatient and will
be given a drug called imatinib (Glivec®), which is given in tablet form on a long-term basis.
Some people with chronic lymphocytic leukaemia will not need any treatment when
they are first diagnosed if the leukaemia is not causing any symptoms and their blood counts
are satisfactory. A few people will never require treatment. Most patients, however, will
require treatment with chemotherapy tablets at some time. The chemotherapy that is usually
given is either chlorambucil or a combination of fludarabine plus cyclophosphamide. Many
patients now also receive rituximab, which is a type of drug called a ‘monoclonal antibody’.
This is given as an infusion into the veins.
The treatment of lymphoma
Patients with Hodgkin lymphoma will usually be treated with a combination of
intravenous chemotherapy drugs called ABVD, which stands for Adriamycin® (doxorubicin),
bleomycin, vinblastine and dacarbazine. This treatment can normally be given in the day ward.
The number of courses of chemotherapy required and the need for a course of radiotherapy
will be determined by the stage of the lymphoma, in addition to a number of other factors.
Specialised scans called positron-emission tomography (PET) scans, which help to determine
how effective the treatment has been, are becoming increasingly commonly used to help
doctors decide on the best treatment for people with Hodgkin lymphoma.
If people with low-grade non-Hodgkin lymphoma have no symptoms they might
not need any treatment at all when they are first diagnosed and a ‘watch and wait’ policy
is adopted. Radiotherapy might be considered if the lymphoma is found in only one area,
such as the neck (stage I) and in some people with stage II disease. For all other stages,
when treatment is required, a combination of drugs is given – including chemotherapy drugs,
rituximab and steroid tablets. Some of these are given in tablet form; some are injected into
the veins or added to a drip.
Patients with high-grade non-Hodgkin lymphoma require treatment soon after
the lymphoma diagnosis is confirmed. They usually receive a combination of drugs, including
chemotherapy drugs, rituximab and steroid tablets. The most commonly used combination
of these drugs is known as ‘R-CHOP’, which stands for rituximab with cyclophosphamide,
hydroxydaunorubicin (doxorubicin), Oncovin® (vincristine) and prednisolone. This is usually
given 3-weekly for six courses but this varies, depending on the stage of the disease.
Most people with lymphoma will receive their treatment on a chemotherapy day ward.
People with a high-grade non-Hodgkin lymphoma which is confined to one area might
receive fewer courses of chemotherapy and then have a course of radiotherapy. Radiotherapy
might also be considered in certain other situations in people with this type of non-Hodgkin
lymphoma.
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
5/7
Follow-up
How are people with leukaemia followed up?
Once intensive treatment is finished patients with acute leukaemia usually continue to attend
the outpatient clinic indefinitely, although the frequency of visits usually decreases with time.
People with CLL will usually attend the hospital outpatient clinic, although some patients with
very early CLL might have their blood checked periodically by their GP. People with CML are
usually on continuous treatment and attend the outpatient clinic on a regular basis.
How are people with lymphoma followed up?
Once treatment is completed, patients are seen at the outpatient clinic. If they remain well,
the frequency of visits usually decreases with time. Some people with high-grade non-Hodgkin
lymphoma or Hodgkin lymphoma might be discharged 5 years after finishing treatment if
they have remained well and tests show no evidence of disease. People with a low-grade
non-Hodgkin lymphoma (such as follicular lymphoma) usually continue to attend long-term.
Follow-up policies vary from centre to centre, however, and you will be given guidance on
what to expect.
Acknowledgements
The Lymphoma Association would like to thank Dr Pam McKay, consultant haematologist, and
Sister Nan Ramsay, both of the Beatson West of Scotland Cancer Centre, Glasgow, for writing
and reviewing this article.
More information
The Lymphoma Association produces a wide range of booklets and information sheets on all
aspects of lymphoma and its treatment (including information on CLL). Visit our website at
www.lymphomas.org.uk or telephone our freephone helpline on 0808 808 5555 if you would
like to receive any of this information or if you would like to talk to someone about your
lymphoma.
Useful organisations
Leukaemia Care provides care and support to all those whose lives have been affected by
leukaemia, lymphoma, myeloma and allied blood disorders. Their work extends to the welfare
of families and carers, as well as that of patients themselves.
One Birch Court
Blackpole East
Worcester WR3 8SG
 08088 010 444 (24-hour CARE line)
[email protected]
www.leukaemiacare.org.uk
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
6/7
Leukaemia & Lymphoma Research is dedicated exclusively to researching blood
cancers, including leukaemia, lymphoma and myeloma.
39–40 Eagle Street
London WC1R 4TH
 020 7504 2200 (Mon–Fri, 9am–5pm)
 [email protected]
www.leukaemialymphomaresearch.org.uk
Macmillan Cancer Support exists to improve the lives of those affected by cancer by
providing practical, medical, emotional and financial help, as well as pushing for better cancer
care.
89 Albert Embankment
London SE1 7UQ
 0808 808 0000
 via website
www.macmillan.org.uk
This publication should not be used for medical diagnosis or treatment and is for
information only. Although the Lymphoma Association has taken great care in researching
and putting such information together, we cannot give any warranties as to its accuracy.
Please consult a medical professional if you have concerns about your health or treatment.
See www.lymphomas.org.uk for our full disclaimer.
© Lymphoma Association
PO Box 386, Aylesbury, Bucks, HP20 2GA
Produced 21.06.2011
Due for revision 2014
Leukaemia and lymphoma – what’s the difference?
Lymphoma Association, registered charity no. 1068395
7/7
Download