As you know, any tissue of the body can undergo malignant transformation. The hematopoietic system is no exception. Diseases of this tissue are divided into 2 groups: myelo- and lymphoproliferative neoplastic processes. Tumor pathology of the hematopoietic tissue is called hemoblastosis. This is the general name for all varieties of neoplastic processes. In most cases, hemoblastoses develop in childhood. However, some blood cancers occur exclusively in adults. Hematologist deals with blood pathologies. He recognizes the type of hemoblastosis and prescribes the appropriate treatment. The main method of normalizing blood composition is chemotherapy.
Hemoblastosis - what is it?
Like all oncological pathologies, hemoblastoses are characterized by the appearance and reproduction of immature cells. These may be undifferentiated elements of the hematopoietic or immune system. In the first case, the process is myeloproliferative in nature andcalled leukemia. The reproduction of immature immune cells is referred by some authors to lymphomas, others to hematosarcomas. Previously, such blood cancers were called leukemia.
Unfortunately, hemoblastosis is one of the main causes of death of the population from cancerous tumors. In the oncological structure, blood pathologies occupy the 5th-6th place. These tumors are especially common in preschool children. The main criteria for the disease include: intoxication, hemorrhagic, hyperplastic and anemic syndrome. Only after a qualitative blood test can a diagnosis of hemoblastosis be made. An ICD-10 code is assigned to each of the types of leukemia.
Causes of the development of diseases of the hematopoietic system
Blood cancer, like other neoplasms, usually develops suddenly, without any previous signs. Therefore, it is possible to recognize the cause of cell transformation in rare cases. Nevertheless, it has been proven that the development of leukemia may be associated with provoking factors that preceded leukemia long before its onset. Such reasons include radiation. Blood disease (hemoblastosis) often occurs after radiation exposure to the body. Therefore, the etiological factors include ionizing and ultraviolet radiation, including frequent diagnostic procedures and therapy for other tumors. Among other reasons for the development of hemoblastoses, there are:
- Viral impact.
- Congenital genetic anomalies.
- Exchange violationsamino acids.
- Exposure to chemical carcinogens.
Epstein-Barr virus is found in some patients suffering from malignant lymphomas and hemoblastoses. This pathogen not only weakens the immune defense, but also activates the oncogenes present in the body. The role of retroviruses in cell regeneration is also being studied. Among genetic diseases, risk factors include: Klinefelter syndrome, Down syndrome, Louis Bar. Chromosomal abnormalities and congenital metabolic disorders lead to impaired differentiation of myeloid and lymphoid cells.
Chemical carcinogens include some antibacterial and cytotoxic drugs. Examples are the following drugs: Chloramphenicol, Levomycetin, Azathioprine, Cyclophosphamide, etc. Therefore, the risk of leukemia is increased in people receiving chemotherapy for malignant neoplasms. There are also carcinogens at enterprises using benzene and other harmful substances.
Mechanism of development of leukemia
The pathogenesis of all oncological diseases is based on a violation of the differentiation of cellular elements. Hemoblastosis is a pathology in which immature myelo- and lymphocytes appear in the blood. Impaired differentiation can occur at any stage of progenitor cell development. The earlier the disorder occurs, the more malignant the disease. It is believed that under the influence of etiological factors, mutations occur in the genes. This leads to a change in the quality of chromosomes and their rearrangement.
Allhemoblastoses (leukemias) are of monoclonal origin. This means that all pathological cells in the blood are the same in structure. Normal differentiation of blood cells goes through several stages. The precursor of all tissue elements is the stem cell. As it matures, it gives rise to myelo- and lymphoblasts. The former are converted into red blood cells and platelets. The second group of cells gives rise to the elements of the immune system of the blood, that is, leukocytes.
Impaired differentiation of stem cells leads to the fact that the composition of the blood is completely changed. In the study it is impossible to determine a single normal element. All of them are the same, so they cannot perform the necessary functions. This explains the fact that undifferentiated hemoblastosis is considered the most malignant cancer and has a worse prognosis. If maturation is disturbed in the later stages, the cells partially or fully function. Therefore, the prognosis for highly differentiated cancer is more favorable. However, even fully mature cells are characterized by pathological division and displace other normal blood elements.
Varieties of hemoblastoses in adults and children
Given the pathogenesis of hemoblastosis, the disease is primarily classified according to the degree of differentiation of pathological cellular elements. Not only the clinical picture of the disease depends on this, but also the selection of the correct treatment. Depending on what type of cells has undergone changes, myelo- and lymphoproliferative hemoblastosis is isolated. Each of these groups is divided into acute andchronic leukemia. The first is considered more unfavorable due to the low degree of differentiation. To detect acute leukemia, it is necessary to confirm the presence of blast cells. In the myeloid type, precursors of monocytes, megakaryocytes, and erythrocytes can be pathological substrates. Acute lymphoid hemoblastosis is a serious disease that occurs in childhood. In this pathology, immune cells have pathological activity. Among them are the precursors of B- and T-lymphocytes, as well as antigens CD-10 and CD-34.
Chronic hemoblastoses are also subdivided into myeloid and lymphoid. The former are characterized by an increase in the number of neutrophils, basophils, eosinophils or their mature precursors. The number of blast cells in chronic myeloid leukemia is small. In most cases, the disease develops against the background of genetic mutations. Chronic lymphocytic leukemia is more commonly diagnosed in the elderly male population. Sometimes the pathology is inherited. A similar ailment is divided into the following groups:
- T-cell leukemia.
- Paraproteinemic hemoblastoses.
- B-cell leukemias.
All of the listed pathologies are related to malignant immunoproliferative processes. Paraproteinemic hemoblastoses, in turn, are classified into the following:
- Heavy chain disease.
- Primary Waldenström macroglobulinemia.
- Myeloma.
The peculiarity of these varieties of hemoblastoses is thatat them fragments of immunoglobulins (paraproteins) are synthesized. The most common form of this group of leukemias is myeloma.
Clinical picture in chronic blood neoplasms
How does hemoblastosis manifest itself? Symptoms of lymphoproliferative blood diseases are associated with impaired immunity. Patients with chronic leukemia complain of infections that occur despite treatment. Also, the symptoms of lymphoid hemoblastosis include severe allergic reactions that were not previously observed. This is due to the restructuring of the immune system and its excessive activation. The clinical picture of chronic myeloid leukemia depends on the stage of the disease. At the initial stage, the disease resembles an inflammatory process and is accompanied by a low temperature, deterioration of he alth, and weakness. In the terminal stage, the listed symptoms are joined by: bone pain, lymphadenopathy, an increase in the size of the spleen and liver. With progression, patients are severely malnourished, weight loss occurs, infections join.
Due to the predominance of certain types of cells in the blood, the growth of other elements is inhibited. As a result, anemia and thrombocytopenia may occur. A decrease in hemoglobin levels affects the general condition of the patient. The patient becomes lethargic, the skin becomes pale, there is a decrease in blood pressure, fainting is noted. With thrombocytopenia, hemorrhagic syndrome develops. Its manifestations include various bleeding.
Symptoms of acuteleukemia
Compared to the chronic form of the disease, acute hemoblastosis is more pronounced. The symptoms of this disease are growing rapidly, and the person's condition is noticeably deteriorating. The following syndromes predominate in the clinical picture:
- Anemic.
- Hemorrhagic.
- Lymphoproliferative.
- Hepatosplenomegaly syndrome.
- Intoxication.
- Immune System Damage Syndrome.
Due to the inhibition of hematopoiesis, patients have severe anemia. This is especially pronounced in lymphoid leukemia. Despite ongoing therapy, hemoglobin in patients remains low. The characteristic signs of anemia include pallor, severe weakness, dry skin, damage to the mucous membranes, and taste perversion. Hemorrhagic syndrome is characterized by the appearance of red dots and spots on the skin (petechiae, ecchymosis). With a pronounced lack of platelets, external and internal bleeding occurs, which leads to the progression of anemia.
Intoxication in patients suffering from hemoblastoses is manifested by a decrease in appetite, pain in muscles and bones, and constant weakness. Like any oncological process, blood cancer is accompanied by weight loss. Acute hemoblastosis is almost always accompanied by lymphadenopathy. From the increase in the size of the thymus, respiratory failure can develop. In addition to hypertrophy of all groups of lymph nodes, hepato- and splenomegaly is noted. The clinical picture of hemoblastosis in children is the same as in adult patients.
The progression of blood cancer leads todamage to almost all organs and systems. First of all, the testicles and kidneys are affected. The main complication of the disease is DIC, that is, a violation of blood clotting. Also, patients often suffer from joining infections that develop against the background of immunodeficiency.
Methods for diagnosing hemoblastoses
Acute hemoblastoses have the following diagnostic criteria: a decrease in hemoglobin level with a normal color index, neutropenia, thrombocytopenia and lymphocytosis in the CBC. The number of leukocytes differs depending on the type of disease. With hemoblastoses of the lymphoid type, their level increases sharply (tens and even hundreds of times). A decrease in the number of leukocytes can be observed with myeloproliferative blood cancer. The main diagnostic criterion for an acute pathological process is the presence of blast cells and the absence of intermediate elements. A similar picture of the blood is called a leukemic failure. To confirm the diagnosis, a bone marrow analysis and a study for myeloperoxidase, chloroacetate esterase, PAS reaction are performed.
Additional diagnostic criteria include: chest x-ray, cytogenetic analysis, ultrasound of soft tissues and internal organs. The research algorithm for suspected chronic hemoblastoses is the same. In the KLA, there is a shift in the leukoformula to intermediate blood elements (promyelocytes). Blast cells may be present in small numbers. In chronic myeloid leukemia, the Philadelphia chromosome appears in the bone marrow. Serological testing and ELISA help to confirm lymphoid type blood cancer.
Hemoblastoses: differential diagnosis of diseases
On the basis of only clinical data, it is difficult to make a diagnosis: hemoblastosis. After all, the manifestations of this disease are similar to other systemic pathological processes. Depending on the predominance of a particular syndrome, leukemia is differentiated from Hodgkin's disease, aplastic and hemolytic anemia, HIV infection. If respiratory failure comes first, the disease resembles a tumor of the mediastinum or lungs. Only after a study of blood and bone marrow can hemoblastosis be distinguished from the listed diseases.
Treatment of acute and chronic leukemia
How is hemoblastosis diagnosed? The ICD-10 code is different for each type of leukemia. An acute myeloid neoplasm of the blood is assigned the code C92.0, a chronic process - C92.1. Lymphoproliferative leukemias are coded as C91.0-C91.9. Depending on the diagnosis, a treatment regimen is selected. The main method is chemotherapy. For treatment, the drugs "Vincristine", "Endoxan", "Doxylid", "Cytarabine" are used. The choice of drugs depends on the type of hemoblastosis. Some schemes include the hormonal drug "Prednisolone". Treatment is aimed at induction and consolidation (consolidation) of remission. Then prescribe drugs for maintenance therapy. Among them are the medicines Mercaptopurine and Methotrexate.
In addition to chemotherapy, radiation treatments and bone marrow transplantation are used. In some cases, a splenectomy is performed.
Hemoblastoses: prevention and prognosis
It is impossible to predict the development of leukemia in advance, so there are no special methods of prevention. People with a burdened oncological history should protect themselves from various radiation and chemical effects.
It should be remembered that some types of leukemia tend to be hereditary. Therefore, in the presence of blood cancer in relatives, it is necessary not only to lead a he althy lifestyle, but also to take OAC periodically. An example is paraproteinemic hemoblastosis. The prognosis of the disease depends on the degree of differentiation of tumor cells and timely treatment. The five-year survival rate is 30 to 70 percent with remission and bone marrow transplantation.
