Leukemia - what is it? Description of the disease, causes, diagnosis, prognosis

Oncology, cancer - these terms cause unpleasant, bordering with fear of association among many of us. When a malignant tumor occurs in an organ, it is removed. And what to do with blood cancer, which continuously moves throughout the body and visits each organ dozens of times a day. Many people consider this disease 100% fatal, but, meanwhile, it is treatable, like any oncology. Its correct name is leukemia or leukemia. What it is? What factors cause it? Are there any remedies that can cure him? Is leukemia transmitted by inheritance? Why do they suffer from small children? Let's try to answer all these questions.

Factories of blood

It is impossible to explain what leukemia is without telling more about blood. It seems like a homogeneous liquid, but in fact there are thousands of microscopic elements - red blood cells, platelets and leukocytes. All of them, within the time allotted to them, grow old and die. The place of the dead immediately occupy new ones. They are produced by the so-called "factories" of the hemopoiesis located in the thymus gland, spleen, lymph nodes, bone marrow of tubular and hip bones. In any production, raw materials are required to produce the final product. On blood-forming "factories" raw materials are stem cells. As necessary, they mutate (differentiate), turning into particles necessary for blood. This process is called maturation of cells. A certain system behind it exercises strict control. Scientists do not know much about this hemopoietic "controller", it is known only that during the maturation stem cells undergo multiple metamorphoses, gradually converting into myelocytes, normocytes, prolymphocytes and others, until they reach the last stage, in which the changes end. For example, the lymphocyte passes the stages of the lymphoblast and prolymphocyte, and the erythrocyte of the stage of erythrocytoblast, pronormocyte, normocytes and reticulocyte. When the work of this complex "conveyor" fails, massively dividing the immature cells from the intermediate stages begins, the chain of further transformations terminates. For example, the case does not reach the lymphocytes, but stops on the lymphoblasts. It turns out an excess of unnecessary useless cells, which accumulate so much that they displace normal hematopoietic sprouts. So there is leukemia. What it is? This is a malignant disease of the hematopoiesis system.

Chronic form

Leukemia is classified according to different signs. According to the nature of the course of tumor processes, they are distinguished by their acute and chronic forms. In this case, these definitions are conditional and do not correspond to the generally accepted ones. So, the forms of leukemia do not depend on the duration of the disease and never pass one into another, but each has stages of remission and relapse. A dangerous feature of leukemia is the rapid transport of blood mutant cells to any organs, which causes the beginning of the tumor process in them .

Let's consider more in detail chronic leukemia. What is it and why is it called? This type of disease is caused by mutations of already formed, ready-to-work blood cells (erythrocytes, leukocytes and platelets). Most often it appears in the age of 50 years and older. Forms of chronic leukemia:

• Myelocytic;
• Neutrophilic;
• Myelosclerosis;
• Basophilic;
• Myelomonocytic;
• Monocytic;
• Erythromyelosis;
• Lymphocytic leukemia;
• Hairy cell leukemia;
• Lymphomatosis;
• Histocytosis;
• Urethrimia;
• Thrombocythemia.

Each of them has its own characteristic symptomatology. For example, with myelocytic leukemia, the only signs of onset of the disease are weakness, sweating, fatigue. The spleen is not enlarged, the blood composition is normal. The only thing that can alert - an increased number of neutrophils in the blood, although this is observed in any infectious processes.

Common features of progressive chronic leukemia are:

• weakness;
• Increased sweating;
• Enlarged spleen;
• Increased lymph nodes;
• Rash on the skin and mucous membranes;
• Necrotic processes of the skin and organs;
• With exacerbation of the blast crisis in the blood and bone marrow;
• infectious diseases;
• Increase in blood count of leukocytes;
• Leukocyte infiltrates in the bone marrow;
• Decreased immunity.

Chronic lymphocytic leukemia

This disease causes mutations in mature lymphocytes, with 90-98% of them occurring in group "B". Here distinguish benign and malignant stages. The latter very quickly passes into the lymphosarcoma. The onset of the disease is almost indeterminate, since the patient does not feel any suspicious symptoms at all, and all blood tests show a norm, including the number of leukocytes. Over time, the sick person begins to get tired faster, sweating appears, and the lymph nodes and spleen slightly increase. Chronic lymphocytic leukemia has an independent form called hair follicular leukemia, characteristic of the villous outgrowths of the cytoplasm, and it contains a lot of phosphatase and is resistant to tartaric acids. With this form, not lymph nodes but a spleen increase. Its second sign is cytopenia, that is, a reduction in the blood of one or all of the immediately formed elements. At the initial stages, the diagnosis of all forms of lymphocytic leukemia is difficult even when performing blood tests, as their results are similar for any infectious diseases. Also prevent properly diagnose inflammatory processes in the lymph nodes, which may not be associated with leukemia. Patients are first treated with antibiotics, and then the diagnosis is clarified by histological and cytological tests, X-rays are performed (leukemia in the lungs results in infiltrates of lymphocytes, enlarged thoracic lymph nodes).

Acute form of leukemia

In childhood and adolescence, acute leukemia is more common. What is it and how dangerous is it? This type of disease is caused by mutations of blood cells in the immature, primary (blast) state. Depending on which forms of primary cells are mutated, the following types of acute leukemias are distinguished:

• Monoblast;
• Myeloblast;
• Erythromyeloblast;
• Myelomonoblast;
• Acute lymphoblastic leukemia;
• Undifferentiated.

Since acute leukemia in the blood is replaced by useful working particles on immature, the blood gradually loses its functions, namely the supply of oxygen and nutrients to the organs. Also, the work of leukocytes to protect the body against foreign microorganisms is significantly reduced or completely lost.

Symptoms of acute leukemia

All types of this disease have the first stage (attack), remission, relapses. It should be noted that both primary and repeated relapse of acute leukemia is possible. The total sommatoma of the disease is as follows:

• Tumor growths in the bone marrow;
• Severe forms of anemia;
• General weakness with shortness of breath and dizziness;
• Bleeding and ulceration of mucous membranes (stomatitis, tonsillitis, ulcers in the esophagus and intestines are common);
• Skin rash;
• Enlargement of the liver, spleen, lymph nodes;
• pneumonia;
• Pain in the bones when they are beaten (causing the growth of mutant cells in them);
• Sepsis and other infectious complications.

The remission phase occurs when immature cells are not found in the blood, in the bone marrow there are no more than 5%, and leukemic growths outside the bone marrow are absent.

The most acute and acute among children in the age group 1-6 years is acute lymphoblastic leukemia. More often they get sick boys.

Since lymphocytes exist in the forms "B" (responsible for the production of antibodies) and "T" (combating foreign particles), lymphoblastic leukemia is divided into several types, each of which mutates certain forms of leukocytes. In percentage terms the "B" -form, whose share is 85%, is in the lead. The peak incidence falls on children from 3 years, since it is at this age that the body actively produces "B" -leukocytes. The "T" -form becomes the leader in adolescents at the age of 14-15, when the thymus gland reaches its maximum size. At the stage of remission with this type of leukemia, there must necessarily be a spinal fluid. A child who has a remission of 5 years or more is considered to be healthy. Survival of children with timely and proper treatment of acute leukemia is 80-85%.

Causes and Diagnosis

Leukemia in adults and children causes disorders in the structure of chromosomes, which can be caused by hereditary defects or external influences. These include:

• Radiation (radiation);
• Carcinogens (drugs, food, chemicals);
• nicotine;
• Chemotherapy of tumors.

The theory of the viral etiology of leukemia has not yet been proven.

Among the hereditary factors there is a significant increase in leukemia among people with Down syndrome, Bloom, Turner syndrome.

Diagnosis of leukemia includes:

• External examination (probing of lymph nodes, detection of changes in mucous membranes);
• Laboratory blood tests for the quantitative composition of erythrocytes, lymphocytes, red blood cells, platelets;
• Bone marrow biopsy;
• PCR (allows to detect the Philadelphia chromosome, if any);
• FISH analysis (shows changes in chromosomes);
• IFT (identifies cells with markers and antigens).

Treatment

Patients with leukemia undergo mandatory chemotherapy (tablets, injections of drugs). This method of treatment allows you to kill all the mutated cells. Chemotherapy courses, as a rule, there are at least two - the main, at the acute stage of the disease course, and preventive, at the stage of remission. At the end of the first stage of treatment and when 100% of the result is achieved, bone marrow cells are transplanted. If, after all the work done, a relapse occurs , this indicates ineffectiveness of the medications used. In such cases, the treatment regimen is changed. Recurrence of leukemia always reduces the survival rate. Physicians distinguish several types of disease return:

1. By maturity

• Super-early (survival rate of only 10%);
• early;
• Late (success is achieved in 38% of cases).

2. Localization

• Outside the bone marrow;
• Bone marrow (the most dangerous);
• combined.

Very serious and in most cases unpredictable disease is leukemia. What is dangerous about it, except for violations of blood functions? First, the fact that cancer cells spread easily and rapidly throughout the body. Secondly, the most serious complications of the disease course, in which mutant cells can penetrate the membranes of the brain. Third, the side effects caused by all types of leukemia treatment.

Leukemia cattle (cattle)

All animals, including reptiles, also suffer from leukemia, the second name of which is hemoblastosis. It was described back in 1858. At first it was believed that for man this disease is not dangerous. Now, thanks to new research, it is proved that for humans leukemia of animals poses a significant threat. To date, the disease has been well studied, but treatment has not yet been developed. As in humans, leukemia in animals manifests itself in the tumor proliferation of cells of the blood-forming tissues with the release into the blood of a large number of unripe lymphoblasts and myeloblasts. Such mutations cause a bovine leukemia virus. Some optimism instills its instability in high temperatures and chemical preparations. So, in meat, it dies in a minute already at a temperature of 60 ° C, and in milk, at a temperature of 75 ° C, already in 20 seconds. Easily rid of the virus solutions of formaldehyde, chlorine, sodium hydroxide. But it is impossible to destroy it in living animals. The fact is that it affects lymphocytes. Any kind of therapy aimed at destroying the virus of leukemia, at the same time destroys the white blood cells, without which the animal dies.

Symptoms and course of the disease

Leukemia of cattle can be asymptomatic up to 6 years. All this time, the animal is a virus carrier capable of infecting other animals and humans, as well as reproducing sick offspring, thereby spreading the disease in livestock farms. There are 4 stages of the disease:

• Noduleous;
• Initial;
• Deployed;
• Terminal.

At the first stage, normal blood tests show a norm. Identify the disease can only specific blood tests (serological tests, virologic tests). In state farms, they are carried out on a scheduled basis, and in private individuals it often does not suspect that his favorite burenka is deadly sick.

The second stage is characterized by an increase in the number of leukocytes and lymphocytes in the blood, and a large percentage of their immature forms appear. However, there are still no external signs of the disease.

Only in the third stage of leukemia of cattle begins to show clinical symptoms. These include:

• Fatigue of the animal;
• General deterioration, exhaustion;
• Decrease in milk yield;
• Problems with the digestive tract (diarrhea or constipation, difficulty chewing);
• Yellowing of mucous membranes;
• Worsening of the heart;
• Numerous edema (in the area of the udder, podgorudka, abdomen);
• Hind legs;
• Eyedropper;
• Enlargement of lymph nodes (sometimes they reach the size of the child's head).

The final stage does not last long. All clinical symptoms are clearly pronounced, a high percentage of mutated leukocytes are detected in the blood, with a tendency to their overall quantitative reduction. The animal loses the ability to fight the disease and dies.

The youngest quickly go through all the stages, and the adult animal sometimes dies instantly, from the rupture of the spleen. This can happen before the onset of symptoms of the disease.

Prevention

Since the treatment of animal leukemia is impossible, prevention is of great importance in the fight against the disease. First of all, it consists in conducting timely analyzes. In large farms, they are performed every year 1 time for all animals and 2 times for bulls-producers. If more than 2 virus carriers are found in the herd, the economy is considered unfavorable. Correction of the situation is conducted in two ways - culling sick animals and replacing the entire population. At the same time, the disinfection of cowsheds is mandatory.

Of great importance is also the prevention of the importation of young animals to the already existing livestock. All imported animals must be checked for oncornavirus.

Is there leukemia of milk and meat obtained from sick animals? Unfortunately yes. Milk, obtained from patients with leukemia cows, drink freshly categorically prohibited. Such milk must be surrendered to dairies, where it is subjected to prolonged pasteurization. At home, you can drink it after a long (at least 5 minutes) boiling. Many doctors recommend using such milk only for animal feed.

Meat, if there is no damage to muscle leukemia, can also be eaten after careful heat treatment. If the killed or dead animal is injured by organs and skeletal muscles, then its carcass should be disposed of.