Medical Health Information

Chronic Myeloid Leukemia

In chronic leukemia, the proliferating cells are often reached maturity, unlike acute leukemia, which explains the slower spontaneous evolution.

If chronic myeloid leukemia is only 500-700 new cases per year, this is the first cancerous condition in which a genetic defect has been established. This involves chromosomes 9 and 22, which interact to form an abnormal chromosome called the "Philadelphia chromosome." His major risk is the development phase called acute, active and dangerous.

Symptoms of Chronic Myeloid Leukemia

Chronic lymphocytic leukemia is usually discovered incidentally because in most cases it does not cause symptoms. It is suspected after a simple blood test ("NFS") showing an abnormal increase in cells.

More than 3000 cases detected per year

According to figures from the National Institute of Health Surveillance, 3224 new cases were diagnosed in 2005 and 58% in humans. More than 1,000 deaths are due to disease, which is chronic lymphocytic leukemia ranked 22nd of all cancer deaths.

Diagnosis of chronic leukemia

Chronic myeloid leukemia is often asymptomatic and is discovered incidentally so. However, an increase in the size of the spleen (splenomegaly), identified on clinical examination or ultrasound to decide whether or not a patient discomfort can be a first symptom. Only the study of the karyotype, that is to say, the chromosomes of cells in the bone marrow, can show the presence of the Philadelphia chromosome and the diagnosis of the disease.

Treatments for Chronic Myeloid Leukemia

If the existence of the Philadelphia chromosome has been known for several decades, it was not until the late 90s, with advances in molecular biology, for a specific drug can be developed: imatinib. This is extremely effective because it puts patients in hematologic and cytogenetic remission, which is reflected by the fact that in their bone marrow, there is no longer any cell harboring the Philadelphia chromosome.

On the other hand, it simply administers orally and has exceptional tolerance does not cause nausea or vomiting, or hair loss. Serious side effects only appear in less than 1% of patients.

We note some resistance to this drug. New molecules have been developed such as dasatinib or nilotinib. In some cases, especially in younger patients for whom treatment response is not optimal, it may still be appropriate to use a transplant of hematopoietic stem cells.

We talk about acute leukemia when hematopoiesis is blocked at an early stage of the production of blood cells. Malignant cells that proliferate are so immature (called cells "blast"). They correspond to rapidly changing forms of involving patients' lives in the short term (as opposed to chronic forms). From acute leukemia, we differentiate acute lymphoblastic leukemia, affecting cell lineage (a type of white blood cell involved in the immune system), acute myeloid leukemia, which may affect the precursors of all other cells manufactured by bone marrow (red blood cells, platelets, some other white blood cells such as neutrophils).

Symptoms of acute myeloid leukemia

The most common acute leukemia begins abruptly in a few days, without signs, with a rapid deterioration of the general condition and a combination of symptoms. They often reflect the inability of the bone marrow to produce blood cells normally, due to the proliferation of leukemic cells. Thus, the decrease in production of red blood cells causes anemia whose main clinical signs are pallor, shortness of breath, fatigue, rapid heartbeat ... The decrease in platelet exposed to bleeding, bruising, bleeding gum or skin. Finally, the reduction in the number of white blood cells (neutrophils) may cause infectious problems.

Diagnosis of acute myeloid leukemia

The diagnosis of acute leukemia can not be established after a single blood test. It is essential to make a cytological examination of bone marrow cells. This examination consists of the morphological analysis of marrow cells after removal of these cells by bone marrow aspiration. The myelogram is performed under local anesthesia by puncture of the sternum or iliac spine. Morphological analysis of these cells allows to define the subset of acute leukemia: acute lymphoblastic leukemia or acute myelogenous leukemia. Other laboratory tests allow additional data to better characterize the cells of the disease. Study of cellular proteins (phenotype), and study of cell chromosomes by karyotype can also refine the diagnosis and prognosis.

Treatment of acute myeloid leukemia

The treatment consists of administering chemotherapy, namely the use of a combination of several drugs. The first phase (induction phase) consists of chemotherapy and to the destruction of leukemic cells. However, it also destroys so transient, normal cells of the bone marrow and blood, which is responsible for the patient of a phase of aplasia (absence transient in the blood of normal blood cells). This condition should be carefully monitored because it increases the risk of infection. Then, the blood cell count goes up, and the patient leaves aplasia in which he found himself.

Other sequences of chemotherapy (called consolidation) must then be undertaken, details of which are based on age and risk of recurrence.

In some young patients with leukemia at high risk of recurrence, we can proceed to allogeneic hematopoietic stem cells from bone marrow ("marrow") or blood ("peripheral stem cell transplantation") if there is a donor.

Causes and origins of chronic leukemia

In chronic leukemia, the proliferating cells are often reached maturity, unlike acute leukemia, which explains the slower spontaneous evolution.

Chronic lymphocytic leukemia is the most common cause of leukemia in the West (new cases per year for thirty thousand inhabitants), with a peak frequency to the sixties. Malignant cells are lymphocytes (that is to say, the cells of the immune system), and more particularly, in the vast majority of cases (over 95%), B lymphocytes.

Very rarely, the disease affects not B cells, but another category, T lymphocytes Then it is most often pro-lymphocytic leukemia T.

Diagnosis and symptoms of chronic leukemia

This is a review of the phenotype of blood cells (not bone marrow) that will make the diagnosis. According to their stage of development, the disease is very different and does not require the same treatment. Stage A, the increase in lymphocytes is the only abnormality identified, and it alone justifies any treatment: according to many experts, could even at this stage not to mention cancer, but rather "hyper-lymphocytosis B chronic. "
It simply performs a blood count monitoring every six months or every year, in order to identify a possible aggravation. Studies are underway to better identify chronic lymphocytic leukemia diagnosed at stage A and whose evolutionary potential unfavorable because they require early treatment. It is perfectly possible, even common, to stay in stage A for years.

We speak of chronic lymphocytic leukemia B stage when we find an increase in the lymph nodes in three different regions of the body (eg, cervical lymph nodes, axillary and inguinal lymph nodes or cervical, axillary and spleen). This is due to the fact that the abnormal lymphocytes left the blood and bone marrow to accumulate in these "reservoirs".

Finally, we speak of a stage C when there is a shortfall in production of other blood components such as red blood cells or platelets (related to marrow infiltration by malignant cells in excess), which can lead to anemia or thrombocytopenia. Lymphocytic leukemia pro-T is the most common cause of aggressive signs at diagnosis as the presence of lymph outset, a hyper-lymphocytosis associated with general signs of impaired general condition of the patient.

Treatment of chronic leukemia

At the stage of the disease does not warrant any treatment, but a simple monitoring.
In stage B and C, according to the patient's age and the prognosis of the disease, it can be proposed monochemotherapy orally, both specific since not affect normal lymphocytes and well tolerated because it cause any nausea or alopecia or chemotherapy, namely a combination of several drugs.

The treatment can also be based on the use of monoclonal antibodies, some of which are currently being tested in combination.

Finally, a hematopoietic stem cell transplant may (rarely) be necessary.

Acute Lymphocytic Leukemia

Even if there are chronic leukemias acute leukemia, in all cases, this disease that affects the bloodstream, resulting primarily from the infiltration of tumor cells in the bone marrow and blood.

Bone marrow (called "red", not to be confused with the spinal cord) is in the flat bones: skull, ilium (hip bone), ribs, sternum and spine. In the marrow are produced the three different types of blood cells: red blood cells, white blood cells and platelets. All cells are produced from stem cells in a complex process called "hematopoiesis", which allows their differentiation.

Depending on the type of blood cell affected, but also depending on the stage of hematopoiesis affected by the disease, leukemia can take various forms. Their symptoms, their evolution and their treatments are different as well.

Definition of acute leukemia

We talk about acute leukemia when hematopoiesis is blocked at an early stage of the production of blood cells. Malignant cells that proliferate are so immature (called cells "blast"). They correspond to rapidly changing forms of involving patients' lives in the short term (as opposed to chronic forms).

From acute leukemia, we differentiate acute lymphoblastic leukemia, affecting cell lineage (a type of white blood cell involved in the immune system), acute myeloid leukemia, which may affect the precursors of all other cells produced by the bone marrow bone (red cells, platelets, some other white blood cells such as neutrophils).

Symptoms of acute leukemia

The most common acute leukemia begins abruptly in a few days, without signs, with a rapid deterioration of the general condition and a combination of symptoms. They often reflect the inability of the bone marrow to produce blood cells normally, due to the proliferation of leukemic cells.

Thus, the decrease in production of red blood cells causes anemia whose main clinical signs are pallor, shortness of breath, fatigue, rapid heartbeat ... The decrease in platelet exposed to bleeding, bruising, bleeding gum or skin.

Finally, the reduction in the number of white blood cells (neutrophils) may cause infectious problems.

The number of cases of acute leukemia

In 2005, according to figures from the National Institute of Health Surveillance, over 3000 cases of acute leukemia were diagnosed.

They are ranked 18th in cancer cases in men and 18th in women.

Diagnosis of the disease

The diagnosis of acute leukemia can not be established after a single blood test. It is essential to make a cytological examination of bone marrow cells. This examination consists of the morphological analysis of marrow cells after removal of these cells by bone marrow aspiration. The myelogram is performed under local anesthesia by puncture of the sternum or iliac spine.

Morphological analysis of these cells allows to define the subset of acute leukemia: acute lymphoblastic leukemia or acute myelogenous leukemia. Other laboratory tests allow additional data to better characterize the cells of the disease. Study of cellular proteins (phenotype), and study of cell chromosomes by karyotype can also refine the diagnosis and prognosis.

Treatment of acute lymphocytic leukemia

The treatment consists of administering chemotherapy, namely the use of a combination of several drugs. A first phase of induction chemotherapy is performed. This treatment can be performed in a protected area. According to prognostic factors and quality of the response to the first treatment, bone marrow transplantation may then be necessary for optimal treatment of the disease. If this is not the case, a maintenance phase is performed.

There is a significant risk that the leukemic cells cross the meningeal barrier to attack the central nervous system. Also, lumbar punctures are they systematically and regularly carried out to analyze the cerebrospinal fluid, even in the absence of any symptoms. They can at once detect the presence of abnormal cells, treating them as preventive as curatively by the local administration of drugs (cortisone, methotrexate). In parallel, we perform a prophylactic irradiation of the skull base.