Leukemia (blood cancer) refers to a group of cancers of the hematopoietic system in which too many precursor leukocytes (white blood cells) are produced. Thanks to advances in medicine, leukemia is now much more treatable and in some cases curable.
What is leukemia?
Literally translated, leukemia means “white blood” – affected individuals usually have too many white blood cells in their blood. Generally, leukemia refers to various diseases in which blood formation in the bone marrow is disturbed. Due to the malfunction of certain control genes, incompletely developed white blood cells are released into the blood. These are non-functional, but usually multiply very quickly and uncontrolled. As a result, they disrupt normal blood formation in the bone marrow, producing too few red blood cells, healthy white blood cells and platelets. The immature white blood cells spread throughout the body and can settle in organs such as the spleen, liver, tonsils, lymph nodes and other body tissues.
The function of the blood components
Red blood cells (erythrocytes): They make up 99 percent of blood cells and transport oxygen from the lungs to the various tissues of the body.
White blood cells (leukocytes): These cells fight off pathogens and eliminate defective or overaged endogenous cells. They are an essential component of the immune system. Thus, B and T lymphocytes, as well as granulocytes, belong to the white blood cells.
Blood platelets (thrombocytes): They ensure that bleeding is stopped in the event of an injury. As soon as a vessel is injured, platelets accumulate there and contribute to the closure of the vascular wound. At the same time, they release substances that promote blood clotting.
Four types of leukemia (blood cancer)
Experts essentially distinguish between four different types of leukemia (blood cancer), each of which requires different treatment:
Acute lymphoblastic leukemia (ALL)
Chronic Lymphocytic Leukemia (CLL)
Acute myeloid leukemia (AML)
Chronic myeloid leukemia (CML)
Leukemias arise from blood stem and progenitor cells. In the acute forms, the disease usually appears suddenly and with symptoms such as weakness, bleeding and a tendency to infection. The chronic forms, on the other hand, develop slowly over months or even years and begin insidiously. Acute leukemias in particular have various subtypes, each of which responds to different therapies and whose chances of cure can vary greatly.
Frequency and age
Compared to other cancers such as breast cancer, prostate cancer or colon cancer, leukemia is rather rare. It accounts for about three percent of tumor cases. In Switzerland, around 1,200 people are diagnosed with blood cancer every year. 580 people die of leukemia each year. Almost half of leukemia patients are over 70 years old. Children are rarely affected: Only four out of 100 people diagnosed with leukemia were under the age of 15. Acute lymphoblastic leukemia (ALL), however, occurs particularly frequently in children and is also the most common type of cancer among them. ALL is newly detected in an average of 1 in 100,000 people each year. Acute myeloid leukemia, which primarily affects older adults, is diagnosed in three to four out of every 100,000 people each year.
Center for Hematologic Neoplasms
At the USZ, numerous departments have joined forces to form a Center for Hematologic Neoplasms. The center is certified according to the guidelines of the German Cancer Society (DKG). A team of experts specializing in the medical care of leukemia works closely together here for the benefit of our patients. At DKG-certified centers, patients are treated according to strict quality criteria and, according to current studies, have a better chance of survival on average.
Why degenerate leukocytes develop in some people is unclear. At one point, errors occur in the duplication of DNA in blood progenitor cells. Nevertheless, some factors can increase the risk of developing leukemia. These include:
Chemicals
Radiation
Genetic factors
Certain medications
Tobacco use
The above factors may increase the risk, but do not mean that they must cause cancer.
Symptoms: leukemia manifests with fatigue and pallor
In chronic leukemia, there are often hardly any symptoms to be detected. Therefore, it is often only noticed after a long time or during routine examinations. In acute leukemia, on the other hand, symptoms usually appear suddenly. They can vary greatly depending on how the disease changes the total number of blood cells. Sometimes sufferers suffer from single of the following symptoms, sometimes from several:
Fatigue
Paleness
Fatigue
Bleeding from the nose or gums
Dizziness
Headache
Loss of appetite
Fever
Frequent infections
Night sweats
Enlarged lymph nodes (in lymphocytic leukemias)
In detail, the complaints depend on how the blood is composed:
If too few mature white blood cells are produced, the immune defense functions only to a limited extent. Frequent and sometimes severe infections are the result.
If red blood cells are missing, too little oxygen is transported in the body. That is why those affected can quickly become exhausted and fatigued, for example.
If too few platelets are produced, hemostasis is impaired. As an example, wounds can then no longer be closed as usual and bleeding occurs.
On the other hand, people suffering from blood cancer form too many defective blood cells. Some sufferers may have abdominal pain because the liver or spleen are enlarged. If the leukemia cells affect the central nervous system, dizziness, headaches or paralysis may result. In acute leukemia, the health of affected individuals can deteriorate rapidly. Therefore, such symptoms must be clarified quickly.
Leukemia/Blood Cancer: Diagnosis with us
We already recognize the first signs of leukemia in the blood count. The concentrations of the various blood cells (erythrocytes, leukocytes and platelets) and the blood pigment hemoglobin are measured. A differential blood count provides information about which subtypes of leukocytes are present in the blood and in what concentration. In doing so, we can see under the microscope how many mature and immature leukocytes are present in the blood.
If abnormalities are detected in this blood count, we confirm the diagnosis by performing a bone marrow examination. In this procedure, we remove some bone marrow with a needle from the pelvic bone under local anesthesia and a bone marrow biopsy. Microscopic examination in the laboratory then shows the quantities of bone marrow cells present and what they look like.
Depending on the symptoms, further examinations may be necessary: If we suspect that the central nervous system is affected, we check its fluid (cerebrospinal fluid) with a cerebrospinal fluid puncture and look for leukemia cells. We use imaging techniques such as ultrasound, CT or MRI to see pathologically altered organs or lymph nodes. FDG-PET/CT can also detect increased metabolism in lymph nodes and organs.
Genetic examination
For the treatment of blood cancer it is important to characterize the diseased blood cells as precisely as possible. For this purpose, certain chromosomal regions and genes are examined which may be associated with the development of leukemia. In addition, surface proteins are determined and quantified by immunophenotyping. This information helps us find the best possible treatment.
Self-help groups
The exchange with people who are affected by the same disease can be a great support in coping with the disease. Advice on finding a suitable self-help group is available from Selbsthilfe Zürich. Self-Help Zurich and the University Hospital Zurich are cooperation partners in the national project “Health literacy thanks to self-help-friendly hospitals”.
Second opinion for leukemia
When a cancer diagnosis is made, a second medical opinion is an important decision-making tool. The Comprehensive Cancer Center Zurich supports you with a professional expert opinion. They receive a thorough analysis of the situation as well as personal advice and quick answers to their questions.
We have made significant progress in the treatment of leukemia in recent years. This has significantly improved the prognosis of certain forms of leukemia. However, according to the current state of knowledge, there are hardly any factors that can be influenced in the development of leukemia. Accordingly, we continue to work on improving the diagnosis and therapy of these altogether rare diseases.
“Research into leukemia has also made great progress in recent years. Today, we can differentiate between many different subtypes of leukemia and tailor treatment to the individual form.”
Leukemia basically refers to a group of diseases in which the formation of white blood cells in the bone marrow has degenerated. A distinction is made between chronic and acute as well as between myeloid and lymphatic leukemias. Due to a malfunction, non-functioning white blood cells enter the blood. Because they multiply rapidly, they displace normal hematopoiesis in the bone marrow. There is a lack of healthy white blood cells, red blood cells and platelets.
If the blood cells divide and multiply at a very early and immature stage of their development and the cancer cells divide rapidly, the disease also progresses quickly. This is known as acute leukemia, which, if left untreated, leads to death within a few weeks to months. In contrast, chronic leukemias progress more slowly. Many people are familiar with so-called old-age leukemia (chronic lymphocytic leukemia), which usually occurs in older people and often progresses slowly even without treatment.
Men are more frequently affected than women. Around half of leukemia patients are over 70 years old at the time of diagnosis. Leukemia often develops from a healthy state. However, there are risk factors such as smoking, exposure to chemicals or ionizing radiation and chemotherapy or radiotherapy for a previous cancer.
The symptoms are usually unspecific. The first signs can be, for example, an infection that does not heal, unexplained bleeding or fatigue and a drop in performance. If such complaints persist over a longer period of time, you should have them checked out anyway. The first indication of leukemia – or its exclusion – is usually provided by a blood count examined under the microscope. For an exact diagnosis, bone marrow is taken and examined using various methods: This tells us exactly which type of leukemia is involved and we can tailor the therapy to it.
Research into leukemia has also made great progress in recent years. Today, we can distinguish between many different subtypes of leukemia and tailor treatment to the individual form that the patient is suffering from. In the past, chemotherapy was the main treatment. They are still important today, but are often combined with immunotherapy or targeted therapy. This is how we achieve maximum effectiveness. We can also cure some of the leukemias today. Some patients require a blood stem cell transplant.
Podcast USZ direkt: On the trail of blood cancer
Resident Tharshika Thavayogarajah had a key moment as a teenager. Since then, she has set herself the goal of researching blood cancer and finding new treatment options.
