Leukemia is a type of cancer that affects blood cells, particularly white blood cells at different stages of their maturity (from the initial cell known as stem cell, to the mature differentiated cell) once produced by the bone marrow. These cells, normally responsible for defending the body against infections, multiply in an anarchic manner and invade the bone marrow, blood and organs. There are several forms of leukemia, depending on the type of cells affected and the degree of progression of the disease. What are the causes, symptoms, treatments and prognosis of leukemia in adults? Here is the main information you need to know.
What are the different types of leukemia?
There are several types of leukemia, which are distinguished by the type of cells affected, the degree of maturity of these cells and the course of the disease.
We thus distinguish:
Acute leukemias
- Acute lymphoblastic leukemia (ALL), which develops from immature cells called lymphoblasts. It is more common in children and young adults.
- Acute myeloblastic leukemia (AML), which develops from immature cells called myeloblasts. It mainly affects adults and the elderly.
Chronic leukemias
- Chronic lymphocytic leukemia (CLL), which develops from mature cells called B lymphocytes. It mainly affects people over the age of 50.
- Chronic myelogenous leukemia (CML), which develops from mature cells called granulocytes. It mainly concerns adults aged 40 to 60.
What are the causes of leukemia?
The exact causes of leukemia are not not yet well known, but there are risk factors that can favor its appearance.
Among these factors, we can cite:
- Age, which is the main risk factor for chronic leukemia and acute myelogenous leukemia
- Chromosomal or genetic abnormalities, which may be present at birth or acquired during life, and which modify the functioning of bone marrow stem cells
- Exposure to carcinogens that can damage the DNA of bone marrow stem cells and promote the appearance of abnormal cells
- Immunodeficiency, whether in the context of an infection such as HIV, or linked to taking immunosuppressive drugs, or to an autoimmune disease; all these situations can make bone marrow stem cells more vulnerable to external attacks
What are the symptoms of acute leukemia?
The symptoms of acute leukemia are varied but are mainly the direct consequences of a decrease in normal blood cells, caused by the invasion of the bone marrow by leukemic cells.
These clinical signs can be manifested by:
- A fatigueA shortness of breath a pallor or palpitations linked to anemia (low red blood cells)
- Of the frequent infections or serious linked to leukopenia (decrease in mature white blood cells)
- Of the bleedingbruising or hematoma due to thrombocytopenia (decrease in platelets)
- Of the feverweight loss, loss of appetite or night sweats, due to leukemia cell activity
- Of the bone pain or joints, an increase in the size of the lymph nodes, spleen or liver, or skin lesions, caused by the accumulation of leukemia cells in these organs.
It is important to be alert and therefore to consult, especially when these symptoms appear quite suddenly.
Conversely, chronic leukemias rarely induce symptoms and are often discovered incidentally on a blood test. However, it should be sought in the event of persistent fatigue or repeated infections.
Diagnosis of leukemia
The diagnosis of leukemia is based on several medical tests that detect the presence and type of leukemia cells in the body, including:
- Ae blood test, which measures the number and shape of blood cells. Leukemia often manifests itself as anemia (drop in red blood cell count), thrombocytopenia (drop in platelet count) and leukopenia in acute leukemia (abnormal drop in white blood cells). CLL will, on the other hand, be diagnosed in the event of leukocytosis (increase in the number of white blood cells)
- A myelogram (bone marrow aspiration): this is the test allowing the diagnosis of acute leukemia with certainty. It consists of taking a tissue sample from the sternum or pelvis using a fine needle to analyze it under a microscope in order to identify the type of leukemia and its degree of progression. The diagnosis is confirmed when more than 20% of immature abnormal cells called blasts.
- Genetic tests, molecular karyotypes or even DNA sequencing are complementary explorations allowing the search for chromosomal mutations specific to certain forms of leukemia. These tests are useful for confirming the diagnosis, determining the prognosis and above all helping to find therapeutic targets.
What are the treatments for leukemia?
Treatment of leukemia depends on the type, stage, age and general condition of the patient. It aims to destroy leukemia cells and restore normal blood cell production.
Aggressive treatment can be offered immediately for patients in good health apart from this disease, and aged under 75 years.
The main treatments are: chemotherapy, radiotherapy, bone marrow or hematopoietic stem cell transplantation, immunotherapy, targeted therapy.
What is the life expectancy for leukemia?
The prognosis and chances of survival of leukemia depend on many factors, such as the type (acute or chronic, lymphoblastic or myeloblastic leukemia), stage, response to treatment, complications, and individual patient factors.
