» Leukemia, Acute leukemia, Chronic leukemia in children
Leukemia, Acute leukemia, Chronic leukemia in children
Leukemia, Acute leukemia, Chronic leukemia in children, diagnosis of leukemia, The prognosis for leukemia
Leukemia - a whole group of tumors characterized by uncontrolled proliferation and varying degrees of differentiation of hematopoietic cells. Leukemic cells thus are descendants of one mutated cell clones.
The cause of leukemia, as a rule, chromosome aberrations, ie, changes in the structure of chromosomes in various rearrangement processes resulting in their structure: translocations, deletions, inversions, fragmentation.
In accordance with the traditional classification, all divided into acute leukemia (AL) and chronic (CL). This division is associated with different ability to differentiate these tumors proliferating cells. In the case of acute leukemia differentiation is virtually absent in the blood builds up a huge number of immature, nonfunctional blast cells, which leads to inhibition of normal hematopoiesis of all germs. These signs are detected in the blood of more than 80% of cases. Chronic leukemia (leukemia) gives the population of differentiated cells, usually granulocytic, gradually replacing the normal cells of the peripheral blood.
Acute leukemia can be divided into lymphoblastic and myeloid.
Acute lymphoblastic leukemia (ALL) often develops from a B-lymphocyte precursors (about 75% of cases). There are also B-ALL and T-ALL. Has a value of the presence of cytogenetically Philadelphia chromosome.
Acute myeloid leukemia (acute myeloid leukemia) is often called "nelimfoblastny leukemia" to emphasize its diversity and difference from the ALL, as blasts in this case may have a granulocyte, erythrocyte, and even platelet origin. Acute leukemia nelimfoblastny histologically classified by the letter M with numbers from 0 to 7, for example, M7 - an acute megakaryoblastic leukemia.
Chronic leukemia in children are rare and are also a heterogeneous group of diseases: Chronic lymphocytic leukemia characterized by proliferation of small lymphocytes in the bone marrow, peripheral blood and lymph nodes, spleen and liver. Chronic myelogenous leukemia (CML) is characterized by proliferation of stem cells, which is often accompanied not only by increasing the number of granulocyte precursors, but also red blood cells and platelets. A distinctive feature is the cytogenetic feature - the presence of the Philadelphia chromosome, as well as Power phase of the disease. There are a slow phase, accelerated phase and final phase of the disease. Hairy-cell leukemia is characterized by a proliferation of well-differentiated B-lymphocytes with development of pancytopenia and splenomegaly. The disease is characterized for the elderly and more often in males.
The diagnosis of leukemia put together research on the blood and bone marrow. When the diagnosis is crucial is not the clinical picture, and cytogenetics, morphology and immunology of blasts detected. From the options identified in this will depend not only on the final statement of diagnosis, but also the prognosis, treatment and outcome of disease.
The prognosis for leukemiagenerally more favorable in children (1-9 years), and also depends on the type of pathology, cell type and timing of detection of the disease.
The basis of the treatment of leukemia is chemotherapy. The treatment protocol today, but because each type of pathology and some of its features are relevant to the choice of treatment protocol. In acute leukemia treatment based on chemotherapy. Its efficiency is higher in acute limfolekoze reaches 95%. In acute myeloid leukemia efficacy of chemotherapy is more than 80%, but is often accompanied by complications, and 5-year remission was observed in only 40% of patients, while relapse in ALL - a rare phenomenon.
In the treatment of CML is not the effectiveness of chemotherapy is 20-40%. The best results so far give an allogeneic bone marrow transplantation. Satisfactory results are obtained by alpha-interferon therapy. Recently, great hopes are placed on drugs that block the tyrosine kinase activity of the protein Bcr-Abl, for example, the drug STI-571. It is believed that these drugs can be used for maintenance alone, ie, for the prevention of blast crisis.
In general, the treatment of leukemia should be conducted in a specialized department, with the possibility of applying the most modern and effective treatment, which ensures a greater likelihood of complete remission and full recovery from a full range of therapeutic interventions.