What causes blood cancer 1

Acute lymphocytic leukemia (ALL)

Acute lymphatic leukemia (ALL) is a malignant disease that starts from immature lymphocyte precursors. ALL is the most common form of childhood leukemia; it is rare in adults. Intensive research work has been carried out in the past decades in the field of ALL and the number of cures has increased significantly as a result. A diagnosis of ALL should therefore not lead to hopelessness. A previously incurable disease has become curable in many cases!

Acute lymphatic leukemia (ALL) is a malignant disease of the blood-forming system (blood cancer) in which an early stage of the lymphocytes degenerates and multiplies in an uncontrolled manner. Lymphocytes are white blood cells and are part of the immune system. Their reproduction and renewal are strictly regulated in healthy people. At ALL, this process has gotten out of hand:
Due to changes in the genetic material of an immature preliminary stage of the lymphocytes, the affected cell begins to divide and multiply unchecked, but without developing into normal, functional lymphocytes. The resulting cells are called lymphatic blasts or Lymphoblasts designated. They spread rapidly in the bone marrow and prevent the formation of healthy blood cells there. The blasts are finally distributed in the body via the blood and the lymphatic system and can attack and damage other organs.

Causes and frequency

Acute lymphoblastic leukemia is not a hereditary disease and, like other forms of cancer, is neither contagious nor can it be transmitted to other people. ALL is caused by malignant genetic changes in the bone marrow that are acquired over a lifetime. Ionizing radiation and certain chemical substances are considered risk factors for this. Even some drugs that are used to treat cancer can in rare cases trigger what is known as secondary ALL years later. In the vast majority of cases, however, it remains completely unclear what caused the disease.

ALL is a rare cancer. About 1.1 new cases per 100,000 population are diagnosed each year. ALL can affect all age groups but is most common in children under 5 years of age (5.3 cases per 100,000 population per year). From the age of 6, the likelihood of developing ALL decreases. In adults, the incidence of the disease increases steadily again from the age of 50. In those over 80 years of age, around 2.3 people per 100,000 inhabitants fall ill every year, with men being affected somewhat more frequently than women.


The symptoms of ALL usually develop within a few weeks. They arise on the one hand from the insufficient number of normal blood cells and on the other hand from the infestation of organs with lymphatic blasts:

  • Anemia (Anemia, decrease in red blood cells) leads to paleness, tiredness, fatigue, decreased performance, shortness of breath, general weakness and malaise
  • Causes a decrease in platelets (thrombopenia) Bleeding (small punctiform skin bleeding (petechiae), bruises, nosebleeds, prolonged bleeding e.g. after a visit to the dentist or after injuries, prolonged menstrual periods in women)
  • Reduction in white blood cells (leukopenia) increases the number of cells Susceptibility to infection
  • Increase in leukocytes (leukocytosis) due to the overproduction of lymphatic blasts
  • Joint and bone pain through the spread of blasts in the bones, in about a third of patients (especially in children)
  • Organ involvement:
  • Swelling of the organs of the lymphatic system (lymph node swelling, enlargement of the spleen with a feeling of pressure in the left upper abdomen, enlargement of the liver with a feeling of pressure in the right upper abdomen, enlargement of the thymus gland or the lymph nodes in the chest with shortness of breath, swelling of the veins in the neck area)
  • although rare: involvement of the brain, the spinal cord or the meninges with neurological changes such as headaches, sensitivity disorders or nerve paralysis; the nerve paralysis can manifest itself as double vision, drooping eyelids or corners of the mouth
  • Involvement of other organs (skin, mucous membrane, testicles or breast) is rather rare in ALL initial illnesses, more often in relapses
  • Development of a tumor in the mediastinum (space between the sternum and thoracic spine) (only for T-ALL)

Many patients also lose their appetite and lose weight. Half of the patients have a fever, which can be observed as a result of the leukemia or in connection with co-existing infections. Some patients have hardly any symptoms and the leukemia is discovered by chance during a routine blood test.

All symptoms described also occur in the context of other, comparatively harmless diseases and in most cases have nothing to do with leukemia. If the symptoms persist, however, it is advisable to have the cause clarified by a doctor. If acute lymphoblastic leukemia is actually present, therapy must be started as soon as possible.

Diagnosis of ALL

If leukemia is suspected, extensive blood and bone marrow tests are necessary to first confirm the diagnosis and then determine the type of leukemia. With the help of so-called imaging procedures, the extent of the disease is also determined.

If the family doctor / internist finds evidence of acute leukemia based on the medical history and physical examinations, he will first examine the blood. If the suspicion of leukemia is confirmed, e.g. because immature cells are found in the blood, anemia or thrombopenia is present, the diagnosis must also be confirmed by analyzing the bone marrow. Such an examination is carried out at a specialized hospital by a specialist in blood and cancer diseases (hematologist / oncologist). He takes bone marrow from the hipbone or sternum with a syringe under local anesthesia (bone marrow puncture). This short, outpatient procedure can be a little uncomfortable for the patient as it takes a few minutes for the bone marrow to get into the syringe.
The subsequent laboratory tests of the bone marrow include the external, genetic and immunological characteristics of the affected cells. With the help of the analysis, in addition to the type of leukemia, the exact subtype of the disease can also be determined. Since the subtypes of acute lymphoblastic leukemia differ significantly in their disease course, prognosis, and response to different therapies, a thorough examination of the bone marrow is crucial in order to develop a suitable treatment plan.

If ALL is detected, additional examinations are required, depending on the individual case, in order to be able to rule out other organs in the body being infected with lymphatic blasts. These include chest x-rays, computed tomography, and ultrasound scans of the heart and other internal organs. In addition, a sample is taken from the spinal cord fluid (lumbar puncture) to determine whether there is leukemia in the brain.

In the further course after the start of therapy, bone marrow punctures and other check-ups are necessary again and again. For example, MRD diagnostics can be used to check whether the leukemia has completely regressed (remission), and an impending relapse can be detected at an early stage.

ALL subgroups and risk factors

ALL is not a uniform disease. Since malignant changes in the lymphocytes can occur at different stages of cell development, there are different subtypes of ALL (Fig. 1).

Figure 1: Development of the ALL subgroups from lymphatic cells of different stages of maturity. The various forms of ALL can develop based on the developmental stages of normal B and T cell maturation (blue background) (yellow background). The blasts carry the characteristics of the healthy cell from which they are derived.

The lymphatic blasts bear the characteristics of the cell from which they are derived, and their stage of development can be either immature or mature. The subtype of ALL and the underlying genetic changes can be determined by means of comparative laboratory tests such as microscopy, cytochemistry, immunophenotyping, molecular genetics, cytogenetics or in situ hybridization. With the help of immunophenotyping, two main groups of ALL can be distinguished: the T-cell ALL and the B-cell ALL. The following table shows the frequencies of the individual subgroups.



B-cell ALL
Common ALL
Maturity B ALL

75 %
20 %
40 %
10 %
5 %

T-cell ALL
Pro- / pre-T ALL
Cortical / thymic T ALL
Maturity T ALL

25 %
6 %
13 %
6 %

In some of the patients with common or pre-B-ALL, a genetic change also occurs, which is known as the Philadelphia chromosome (Ph + ALL; pronounced: Philadelphia positive ALL) or translocation t (9; 22). Ph + ALL occurs mainly in older patients and is less responsive to conventional chemotherapy. In recent years, however, new drugs have been developed, which has significantly improved the results of the treatment and the prognosis for the affected patients.

Another special form of ALL is the so-called Burkitt lymphoma which resembles the mature B-ALL. In contrast to the mature B-ALL, however, there are fewer lymphatic blasts in the bone marrow in patients with Burkitt's lymphoma. The diseased cells primarily colonize the lymph nodes. Burkitt's lymphoma requires different treatment than the other ALL subgroups, but usually responds well to the appropriate therapy.

Risk factors

In the course of various studies it has been found that the chances of recovery from acute lymphoblastic leukemia depend on various risk factors. These factors allow a prognosis of how well a patient will react to conventional therapy and how high the probability is that the patient will suffer a relapse (relapse). Relapse means that the leukemia cells multiply again after the disease has initially been suppressed. The decision as to which therapy is right for a patient is therefore made on the basis of the following risk factors, among others:

  • Subgroup of the ALL
  • Age of the patient
  • White blood cells (leukocytes) count at diagnosis
  • General health of the patient
  • Response of the patient to therapy

After reviewing these risk factors, patients are assigned to a risk group so that they receive the therapy that offers the best chance of recovery for their individual case. Patients in an unfavorable risk group receive more intensive (stronger) therapy to reduce the risk of relapse. In this case, risk merely indicates an increased probability. No one can predict with certainty whether a patient will ever suffer a relapse despite risk factors.

The prognosis for ALL shows a wide range of fluctuations in the individual risk groups. The figures for leukemia-free survival are between less than 10% and well over 50%. Taken together, ALL can now be cured with intensive combination chemotherapy in 35-50% of all cases.

Treatment of acute lymphoblastic leukemia

ALL is a serious illness that, if left untreated, leads to death within a few weeks. It is therefore extremely important that therapy is started immediately after diagnosis. The most important part of treatment for ALL is chemotherapy with accompanying therapy to treat the side effects. In individual cases, radiation therapy or a bone marrow transplant can also be used. All components of the therapy serve to kill the leukemia cells everywhere in the body as completely as possible so that the bone marrow can resume its original function - blood formation.

Treatment of ALL should, if possible, be carried out in a clinic that has experience in the treatment of leukemia - especially ALL. You can find out more about choosing the right clinic here. Since the treatment is lengthy and stressful, patients and their relatives should inform themselves comprehensively about the planned process. The attending physician will speak to the patient in detail and inform him about all treatment options.


In chemotherapy, a patient is given drugs called cytostatic drugs that specifically inhibit the growth of leukemia cells. Since a single drug is usually not enough to destroy all blasts, several drugs with different modes of action are combined. They are given as an infusion, syringe or in the form of tablets. Chemotherapy is divided into several cycles, which are separated from each other by pauses (intervals) in which healthy cells can regenerate. To assess the success of the therapy, the bone marrow and other affected regions are checked at regular intervals.


Lymphatic blasts can also affect the brain, where chemotherapy alone does not kill them adequately. That is why irradiation of the skull is an integral part of treatment in ALL. It should safely eliminate the leukemia cells in the skull in order to prevent these blasts from forming the starting point for a relapse of the disease. In Burkitt's lymphoma or T-ALL, irradiation of the mediastinal space (space in the chest between the lungs, the large heart and pulmonary vessels, and the trachea and esophagus) may also be necessary. Some patients develop a so-called mediastinal tumor there, a massive accumulation of lymphatic blasts. Radiation therapy also plays an important role in preparing for a stem cell transplant.

Stem cell transplant

Another treatment option is stem cell transplantation. The aim of this therapy is to replace the diseased bone marrow with healthy ones. In stem cell transplantation, purified blood stem cells from a suitable donor (allogeneic) or, less frequently, from the patient himself (autologous) are infused into the patient. For a successful therapy, all leukemia cells must first be killed. This is achieved through strong chemotherapy and radiation, which in addition to destroying the lymphatic blasts, also destroys the healthy cells in the bone marrow. Since this is a stressful and risky therapy, the patient must be eligible for a stem cell transplant with regard to their general condition and age. In ALL, a stem cell transplant is usually only performed if, based on the characteristics of the leukemia cells, it must be assumed that there is a high risk of relapse or if the patient has already suffered a relapse.

Therapy studies

In Germany, most ALL patients are treated as part of therapy studies. Here, the patient has access to the latest scientific findings and is treated with innovative drugs and correspondingly up-to-date treatment strategies. Participation in a study does not mean that the use of the drugs used is experimental. Rather, the goal is to improve the treatment strategies for ALL in the future. The decision about which study is suitable for a patient must be made together with the attending physician. Various criteria play a role, e.g. disease characteristics, disease phase, pretreatment, age and risk factors. The ultimate decision to participate in a study is always made by the patient himself.

More than 100 clinics throughout Germany are participating in the studies of the German study group for acute lymphoblastic leukemia in adults (GMALL study group) and are based on the therapy recommendations of this study group. This is important because ALL is a very rare disease and individual doctors hardly have the opportunity to gain extensive experience. Patients who take part in GMALL studies or are treated according to GMALL therapy recommendations can also give their consent to their health data being stored in a central register in pseudonymised form. These data will also help to further improve the chances of recovery for ALL patients in the future. The current studies of the GMALL can be found in the German Leukemia Study Register. Children are treated as part of the pediatric therapy studies for ALL (BFM study group). Young people between the ages of 15 and 18 can be treated in both study groups.

Treatment options for a relapse

If the ALL relapses, chemotherapy is performed again first. For late relapses, induction therapy can be repeated to achieve complete remission again.In the event of early relapses or if the disease does not respond to therapy (therapy failure), various possibilities, e.g. with new drugs, are explored as part of therapy studies. Here it is important that the treating physicians are informed about all currently available therapy options. The goal is to achieve a complete remission. A stem cell transplant is often carried out if age and general condition permit and if a donor can be found.


The number of healings in ALL of children and adults has steadily increased over the past decades. However, regular follow-up examinations are required. They include a general physical exam and blood and bone marrow checks. The aim is to detect signs of a relapse or long-term effects of the therapy at an early stage. With the distance between the diagnosis and the end of therapy, the intervals between the examinations lengthen. The attending physician also advises on the possibility of a rehabilitation measure (rehab). It is usually financed by the health insurances and offers a good transition opportunity to find your way back to a "normal" life.

A patient ID card is offered free of charge for all patients who have been treated in a GMALL study or in accordance with a GMALL therapy recommendation. This contains essential information about the disease and the previous treatment of the patient. When a patient presents to a doctor for the first time, the doctor can use the ID to quickly and comprehensively find out about the patient's particular health situation. In the ID card, the patient can also create entries for important information, future treatment appointments or medication currently being taken. In addition, the card also contains information on websites with further up-to-date and helpful information for doctors and patients. On request, you can obtain the patient ID from your treating hematologist or oncologist.

Information brochure of the Competence Network Leukemia

The patient brochure on acute lymphoblastic leukemia (ALL) in adults in the Leukemia Competence Network was produced in cooperation with UCT Frankfurt and Leukemia Aid Rhein-Main g.e.V. reissued. It takes into account the current state of research and explains the treatment options for ALL in adults. In particular, it contains processed information and interesting facts about the disease for patients and relatives. Important contents include: symptoms, diagnosis, treatment options and frequently asked questions about ALL.

➲ to download the brochure

You can get printed brochures from the office of Leukemia Aid Rhein-Main g.e.V. Order via [email protected]

More patient information

Created by: Hehn (Information Center) on July 25, 2014, last change: January 23, 2017

more on the subject

The patient brochure Acute lymphoblastic leukemia (ALL) in adults for free download

Current studies on ALL in the German Leukemia Study Register