Chonic lymphocytic leukemia (CLL)

Description

In CLL, the lymphocytes (subtype of white blood cells) are out of control. Their function in healthy individuals is immune defense. Acute lymphoblastic leukemia (ALL) also originates from the lymphocytes, but the degeneration occurs at an earlier stage of the cells' development.

Chronic lymphatic leukaemia is the most common form of all leukaemias. Every year, 3 out of every 100,000 people contract it. The average age of those affected is 65.

CLL is nowadays often classified as a lymphoma (non-Hodgkin's lymphoma, malignant change in the lymphatic system) because the lymph nodes are also attacked.

The immune system removes countless degenerate cells from the body every day. For CLL, a single altered lymphocyte that is not recognized as degenerate is sufficient to trigger leukemia. Why it is not recognized and destroyed by the immune system is as yet unclear.

Some risk factors are:

• Chemicals (e.g. benzene)
• Ionizing radiation (e.g. radioactivity)
• Infections

In addition, chronic lymphocytic leukemia occurs with different frequency in different groupings.

Frequency in certain groups of people:

• Elderly persons, especially men
• 1st degree relatives (children, siblings) of CLL patients
• Asians fall ill significantly less often

Diagnosis is often coincidental, as symptoms only develop and are noticed as the disease progresses.

Common complaints at the beginning:

• painless enlargement of the lymph nodes
• fatigue
• loss of performance
• fatigue

Complaints with advanced disease:

• Fever
• Night sweats
• weight loss
• Enlarged liver and spleen
• anaemia (lack of blood), resulting in paleness, dizziness, palpitations, shortness of breath
• susceptibility to infections due to lack of white blood cells
• bleeding tendency due to lack of platelets
• Skin changes
• Herpes infections

The diagnosis of chronic lymphocytic leukaemia is often made by chance, e.g. during a routine examination by the family doctor. The elevated values of white blood cells in the blood count are conspicuous.

The laboratory findings are usually followed by a physical examination. Diseased lymph nodes become visible on ultrasound, X-ray or CT (computer tomography).

However, a diagnosis is only confirmed after malignant cells have been detected by means of a biopsy of suspicious lymph nodes or bone marrow puncture.

In exceptional cases, it may be necessary to remove entire lymph nodes and examine the tissue in detail in order to distinguish CLL from other tumor diseases.

What is the treatment depends on the stage of the disease. For up to 20 years, the course of the disease can be benign. This means that apart from fatigue, loss of appetite and enlarged lymph nodes, there are no symptoms.

The actual therapy begins when the lymphocytes are elevated or the platelets and red blood cells are decreased. Other complications may also be crucial. The success rate is not influenced by the (early) start of treatment.

In the case of rapidly developing CLL or certain risk factors that would negatively influence the course, treatment may be necessary very quickly.

Chemotherapy

This is the most important treatment for CLL and can be given with tablets and/or infusions. The treatment success is initially usually very good, symptoms can be kept at bay for years. Rarely, additional radiation therapy is necessary.

Monoclonal antibodies (e.g. alemtuzumab, rituximab) are a more modern therapeutic approach. They bind to proteins that are often found on the surface of leukocytes and destroy them.

Symptomatic treatment serves as an adjunct to chemotherapy. Transfusions help against anaemia, antibiotics against infections. Immunodeficiencies are compensated with antibodies, other disorders of the immune system with cortisone. If individual lymph nodes cause discomfort due to swelling, local radiation can provide relief.

Bone marrow and stem cell transplantation

Young patients (<60 yrs) may receive a stem cell (SCT) or bone marrow transplant (BMT). Stem cells are a type of blueprint for blood cells that are stored in the bone marrow until further development.

A high success rate has so far been shown with autologous SZT. In this case, special stem cells that have already been harvested and purified are transferred to the patient directly after high-dose chemotherapy.

The onset of severe symptoms can be delayed up to 20 years. As the disease progresses, the number of symptoms increases as the organ system is altered.

The prognosis for the individual depends on the stage (lymphocyte count in blood and bone marrow, size of spleen and liver, existence of anemia).