Acute lymphoblastic leukemia. Why it happens?
Acute lymphoblastic leukemia – the most common type of leukemia. The disease develops very rapidly (in contrast to the chronic form). Unlike other types of leukaemia is that form the basis of the disease immature cells are lymphoblasts, or precursors of lymphocytes.
Acute lymphoblastic leukemia: risk factors
Most common acute lymphoblastic leukemia in children. And among all cancer pathologies of the hematopoietic system, this form diagnosed in 75-80% of cases. The peak incidence 2-5 years. Boys suffer more often than girls.
Causes of acute lymphoblastic leukemia are still unknown. To highlight the risk factors:
- infectious diseases in infancy;
- treatment of other pathologies such methods as radiation therapy, cytotoxic chemotherapy and ionizing radiation;
- impact on the mother's body during pregnancy biological mutagens;
- still birth history of the mother;
- a large mass of a newborn baby (over 4 kg);
- chromosomal anomalies and genetic disorders (down syndrome, neurofibromatosis of the first type, primary immunodeficiency, syndrome Shwachman, Fanconi anemia, etc.);
- cancer in close relatives.
Symptoms of acute lymphoblastic leukemia
The clinical picture of the disease distinguish several syndromes.
1) Intoxication syndrome.
- weight loss.
2) Hyperplastic syndrome.
- the increase in peripheral lymph nodes (palpation detected a dense painless conglomerates);
- hepatosplenomegaly, manifested by pain in the stomach (characterized by infiltration of the liver and spleen);
- bone pain, pathological fractures, pain and swelling of the joints (associated with infiltration of the periosteum, the joint capsule, a tumor volume increase of the bone marrow).
- pallor of the skin;
- bleeding of the mucous membranes of the oral cavity;
- hemorrhagic syndrome associated with thrombocytopenia and intravascular thrombosis manifests as petechiae, Achkasov on mucous membranes and skin, vomiting of blood, hemorrhage).
Observed violations of the organs and systems of patient's body:
- The boys noted the initial painless enlargement of the testis.
- In some cases, a significant increase in diagnosed kidney without clinical signs.
- The respiratory system – respiratory distress syndrome, superior Vena cava, leukemic infiltration of the lung tissue, hemorrhage into it.
- From the side of organs of vision, hemorrhage in the retina, swelling of the optic nerve, infiltration of blood vessels.
- The skin may be cyanotic dense painless infiltrative elements.
Diagnosis of acute lymphoblastic leukemia
To confirm the diagnosis, following investigations are carried out:
1. General analysis of blood.
- The hemoglobin is normal or reduced.
- The number of erythrocytes and reticulocytes reduced.
- White cells normal, reduced or elevated.
- There is a thrombocytopenia.
- Found blast cells in the absence of intermediate forms of maturation in the formula of blood – myelocytes and metamyelocytes.
2. A myelogram.
Is bone marrow puncture. Her research is carried out in several stages:
- morphological cytological analysis (hypercity detected by bone marrow infiltration by blast cells and tapering shoots of normal hematopoiesis);
- cytochemical analysis (performed to identify cells belonging to a certain line);
- immunophenotyping (determination of cell type bystudy present on their surface molecules).
3) lumbar puncture.
To determine the presence of lesions of the Central nervous system. Cerebrospinal fluid taken from the spinal canal in the lumbar region. The material studied for the presence of leukemic cells.
4) ultrasound of the abdominal organs.
Conducted to identify the dimensions infiltrated parenchymal organs, enlarged lymph nodes.
5) chest x-ray.
Needed to detect increase of the mediastinum.
6) Biochemical analysis of blood.
Allows to diagnose possible malfunctions of the kidneys and liver.
7) ECG and Echocardiography.
Carried out before chemotherapy.
Treatment of acute lymphoblastic leukemia
Depends on which group risk include patients. If the forecast is initially worse, then a more intense therapy. For patients from the low risk group are less intensive in order to avoid serious complications and unnecessary toxicity.
The stages of treatment:
1. Intensive therapy to achieve remission.
For the first few weeks of multicomponent chemotherapy drugs-cytostatics. They destroy leukemic cells. On remission it is possible to speak while respecting the following conditions:
- the content of blast cells in the bone marrow is less than 5%;
- the absence of blast cells in peripheral blood;
- the restoration of normal hematopoiesis.
Stable remission is possible to achieve 95% of patients-children and in 70-90% of patients-adults.
2. Consolidation of remission.
In the next few months are entered chemotherapy, which should destroy residual abnormal elements.
3. Supportive therapy.
Within two to three years, the patient takes the drugs in pill form.
At the stage of intensive therapy and consolidation chemotherapy are administered intravenously. As a rule. If neuroleukemia funds are injected directly into the spinal canal. Sometimes drugs are delivered directly into the ventricles of the brain. This is a special cavity. To do this under the scalp establish a special Ommaya reservoir. In some cases the use of cranial irradiation (irradiation head).
For the treatment of acute lymphoblastic leukemia can be a bone marrow transplant. This method is used after achieving remission and is indicated only in high risk. As standard therapy in most cases should be a good answer.