Thursday, June 5, 2008

Chronic leukaemia or blood cancer

Written by Dr Rachel Green, consultant haematologist

What is chronic leukaemia?

Leukaemia literally means ‘many white cells in the blood'.

The white cells are part of the body’s immune system, and there are several sub-groups of white cells that have different sorts of roles in recognising and dealing with ‘invaders’ such as bacteria and viruses as well as other types of foreign protein.

All of the blood cells originate in the bone marrow and leukaemia (blood cancer) is a disease where the bone marrow produces large numbers of abnormal white cells. This means that the normal marrow is pushed into smaller and smaller areas. This results in fewer normal cells being produced and gives rise to some of the symptoms.

There are many types of leukaemia, each of which is classified according to the exact cell type affected by the disease.

Chronic leukaemia is a slowly progressive form of leukaemia and tends to involve more mature cell types. It may not need treatment immediately, but if treatment is required it is usually chemotherapy, given in the form of tablets.

The cause of leukaemia is not known.

What are the symptoms of chronic leukaemia?

It is possible to have chronic leukaemia for months or even years without knowing it.

The symptoms are varied, but many people notice:

  • tiredness (due to anaemia)
  • bruising easily (often without having had any blow or fall)
  • repeated infections
  • enlarged lymph glands
  • weight loss
  • night sweats
  • fever.

What is chronic lymphocytic leukaemia?

Chronic lymphocytic leukaemia (CLL) is the commonest type of leukaemia with 3000 to 4000 new cases diagnosed each year in the UK. It is a form of chronic leukaemia characterised by an increased number of lymphocytes, which make up one of the main sub-groups of white cells in the blood. Despite their increased numbers these lymphocytes lack the normal ability of responding to infection by the production of antibodies, so compromising the immune system of the affected person.

CLL is rarely found in people under the age of 40 - the peak age is 65. It is twice as common in men than in women. There are no obvious causes known for CLL.

What are the symptoms of chronic lymphocytic leukaemia?

In addition to the symptoms mentioned above which are common to all forms of leukaemia, specific signs of the disease are:

  • painless enlargement of the lymph glands especially in the neck, armpits and groin.
  • lymph glands in deeper parts of the body may need special scans for diagnosis.
  • sometimes an enlarged spleen (located in the left upper quadrant of the abdomen) may cause discomfort or pain.

How is chronic lymphocytic leukaemia diagnosed?

Often the condition is diagnosed by chance when blood tests are being performed for other reasons.

Although a blood test may give doctors the diagnosis, a bone marrow test is usually done to confirm the diagnosis. Special tests are performed on these samples to help classify the leukaemia as this will influence the kind of treatment required.

Scans and X-rays may also be performed in order to help doctors decide on the best treatment.

How is chronic lymphocytic leukaemia treated?

Treatment is not always required and the patient may just be followed up as an outpatient on a regular basis, sometimes for many years, with no need for further action.

Older people with early stage CLL have a normal life expectancy. Treatment in the form of chemotherapy will be required for those who are unwell or who have many enlarged lymph glands, or who become significantly anaemic.

Chemotherapy is usually given in the form of tablets (usually a medicine called chlorambucil (Leukeran)). Other chemotherapy drugs such as fludarabine (Fludara) (may be used in late stage disease. General bone marrow production of blood cells can occur in more advanced CLL (bone marrow failure) in which steroid treatment with prednisolone (eg Deltacortril) usually allows the bone marrow to recover. Milder degrees of bone marrow failure might adequately be controlled by periodic blood transfusion.

X-ray treatment (radiotherapy) can be given locally, to swollen lymph nodes, or in small repeated doses to the whole body. Infections are more common in people with CLL and need to be diagnosed early and treated vigorously.

Sometimes the spleen, which is also part of the body’s immune system swells up so much in CLL that it gives rise to pain, or it causes a type of anaemia to develop in which the red cells of the blood (oxygen-carrying cells) become fragile, leading to further anaemia. These problems may justify the surgical removal of the spleen.

Bone marrow transplantation may be considered for those patients who are less than 45 years of age and who have an aggressive form of the disease.