Acute leukemia in dogs. Leukopenia is a decrease in the level of white blood cells in dogs. Cancer in a dog: symptoms and types

Leukemia - This is a malignant chronic tumor disease of hematopoietic and lymphoid tissues, which occurs due to the fact that cells cease to differentiate and perform their specific functions (this phenomenon is called anaplasia).

Leukemia in dogs occurs as a result of mutation of lymphocyte precursor cells. The penetration of undifferentiated cells (blasts) into the tissues of the bone marrow, spleen and liver is accompanied by inhibition of hematopoiesis (hematopoiesis) or lymphocytopoiesis (the process of formation of lymphocytes).

Provoking factors in dogs can be hereditary predisposition, ionizing radiation, oncoviruses and some chemicals.

Mostly large and medium-sized breeds (German, Caucasian Shepherds, Boxers, Rottweilers, Labrador Retrievers) aged 3 to 8 years are ill.

The most common diseases in dogs are lymphocytic leukemia and lymphosarcoma (malignant lymphoma).

Lymphosarcoma (malignant lymphoma)

Lymphosarcoma - it is a tumor arising from young or mature lymphoid cells. In this case, as a rule, systemic disease most often affects such organs as the lymph nodes, spleen and liver. Lymphosarcoma in dogs is very common, accounting for more than 80% of all tumors of the hematopoietic system. Malignant lymphoma is classified according to various histological and immunological criteria (origin from T- or B-lymphocytes, degree of maturation, etc.), which is partly important for prognosis and treatment.

Symptoms:

The clinical picture depends primarily on the localization of the tumor. According to the anatomical location, there are multicentric (multiple, usually in the lymph nodes), mediastinal ("thymic leukemia"), gastrointestinal, extranodal (outside the lymph nodes) forms of malignant lymphoma in dogs.

The most common form (up to 85%) is multicentric, accompanied by a generalized painless enlargement of peripheral lymph nodes. As a rule, the onset of the course of the disease is asymptomatic, and further general non-specific disorders develop, such as apathy, anorexia (refusal to eat), fever, emaciation, diarrhea and vomiting are also possible, and anemia occurs in the later stages.

Lymphosarcoma of the gastrointestinal tract accounts for about 5-7% of cases. There are solid and diffuse forms of malignant lymphoma of the gastrointestinal tract. The former are characterized by the appearance of one or more solid tumor nodes in the stomach or intestines, as well as associated lymph nodes, and are accompanied by symptoms of partial or complete intestinal obstruction, including anorexia, vomiting, and emaciation. The diffuse form, as a rule, manifests itself as diarrhea and protein loss (hypoproteinemia).

Laboratory diagnostics

Clinical blood test. In most cases of lymphosarcoma, significant changes in the blood picture are not observed. The number of leukocytes can be normal, low or high, abnormal cells in the circulating blood are found only in rare cases. Sometimes there is mild anemia reflecting chronic illness. With significant bone marrow infiltration, severe hematopoietic disorders are possible, leading to anemia, leukopenia (a decrease in the number of leukocytes), thrombocytopenia (a decrease in the number of platelets) and leukemia (lymphoblasts in the peripheral blood).

Biochemical changes blood sera are organ-specific and depend on the existing complications in a particular organ.

Differential Diagnosis

The symptoms of malignant lymphoma can be similar to those of almost any disease that occurs with enlarged lymph nodes, spleen, liver, and/or changes in the blood and bone marrow. Similar changes can accompany both infectious and autoimmune processes.

Clinical symptoms, x-ray or ultrasound findings, and sometimes laboratory tests are often typical of canine leukemia. To clarify the diagnosis, in most cases, a cytological analysis of cells from an altered lymph node or other organ (spleen, liver, bone marrow) is sufficient. In unclear cases, a histological examination of a removed lymph node or tissue fragment taken with a hollow biopsy needle is indicated.

Treatment

Lymphosarcoma is one of those malignant tumors that responds most well to chemotherapy in dogs. In 10-20% of cases, even a cure is possible. The goal of treatment is to achieve rapid and complete tumor involution (complete remission, depending on the treatment regimen, it is possible in 75-90% of cases) or remission with a good quality of life. With a relapse, you can try to intensify the treatment and achieve a new remission.

In recent years, a variety of treatment regimens have emerged, differing in efficacy, survival time and frequency of adverse events, as well as the complexity of implementation. In general, the protocol is more effective the more drugs are used in combination. The most effective drugs for the treatment of lymphosarcoma are doxorubicin, L-asparaginase, vincristine and cyclophosphamide. In addition, drugs such as prednisolone, chlorambucil, methotrexate, actinomycin-D, mitoxantrone, lomustine, and dacarbazine are often used. Combination chemotherapy (prednisolone twice a day and vincristine intravenously once a week) in some cases can cause a partial or short-term complete remission. Surgical methods of treatment are used primarily for obstructive (obstructive) lymphosarcomas of the gastrointestinal tract, sometimes for localized skin lymphomas.

Forecast

Without treatment, death occurs in about 2-3 months. With chemotherapy with multiple drugs, the likelihood of remission is high and can exceed one year, in about 20% of cases up to several years. With lymphosarcoma of the gastrointestinal tract and all other forms, the prognosis is unfavorable.

Lymphoid leukemia (lymphocytic leukemia)

Unlike lymphosarcoma, in which tumors develop in the peripheral organs of the lymphatic system (lymph nodes), with lymphocytic leukemia, lymphoid cells are synthesized in the bone marrow and released into the blood, that is, what is called leukemia. Lymphocytic leukemia in dogs is about five times less common than lymphosarcoma.

Depending on the cell type and clinical course, acute and chronic lymphoblastic leukemia are distinguished. In acute lymphoblastic leukemia, there is a pronounced infiltration of the bone marrow by immature lymphoblasts with the displacement of normal cells. In most cases, the presence of lymphoblasts in the peripheral blood is observed. If tumor cells do not enter the bloodstream, they speak of aleukemic leukemia. As the disease progresses, secondary infiltration of the lymph nodes, spleen, liver, and non-lymphoid organs may develop. In chronic lymphoblastic leukemia, the tumor population in the bone marrow consists of mature lymphocytes, and the number of lymphocytes in the blood can reach high values, although morphologically they do not differ from normal ones, unlike lymphoblasts.

Symptoms

Acute lymphoblastic leukemia develops anemia, leukopenia, and thrombocytopenia, with susceptibility to infection, a tendency to bleed, and signs of organ failure due to organ infiltration. Death occurs in a few days, a maximum of a few weeks.

Chronic lymphoblastic leukemia, which is more common, slowly progresses, is initially asymptomatic, and is usually discovered incidentally by severe lymphocytosis. Then, general symptoms gradually appear: anemia, polydipsia (increased thirst), polyuria (increased urination), swollen lymph nodes, splenomegaly (enlarged spleen).

Laboratory research

Clinical blood test. Blood changes include absolute massive lymphocytosis with immature lymphoblasts if it is acute lymphoblastic leukemia or mature lymphocytes if it is chronic. Changes in the blood picture in the chronic form are less pronounced than in the acute form. With aleukemic leukemia, there are no blast forms in the blood test and a diagnosis can be made only after examining the bone marrow punctate.

Differential Diagnosis

Reactive leukocytosis or lymphocytosis can be observed not only with leukemia, but also with severe infections, sepsis, trauma, purulent processes accompanied by severe intoxication, with allergic, autoimmune diseases, etc.

Treatment

The prospects for treatment of the chronic form are more favorable than the treatment of acute leukemia in dogs. In cases of asymptomatic disease discovered by chance, observation is sufficient. Treatment can be started after an increase in the number of leukocytes or the onset of symptoms of the disease. The cytotoxin of first choice is chlorambucil, additionally vincristine or prednisone can be used. First you need a weekly control blood test. Subsequently, it can be done less frequently or when clinical symptoms appear.

Forecast

The prognosis for the acute form of the disease is unfavorable. In chronic cases, depending on the symptoms, treatment allows you to achieve a life expectancy of 10-30 months, but, unfortunately, a complete cure is not possible.

Canine leukemia(blood cancer, leukemia) is a chronic malignant viral disease characterized by neoplastic proliferation of hematopoietic and lymphoid tissues, fatal. Leukemia occurs predominantly in adult dogs over the age of three (usually 3-8) years.

Leukemia is mostly asymptomatic chronically. The acute course is rare and is characterized by an increase in many lymph nodes.

Pathogen- RNA-containing oncogenic virus. Canine leukemia virus is morphologically similar to the causative agents of leukemia in other animal species. However, there are significant differences in the antigenic structure.
The stability of the canine leukemia virus in the external environment is small. In cell cultures, when heated to 60°C, it dies after 1 min, and is quickly neutralized with 2–3% solutions of sodium hydroxide, formaldehyde, and other disinfectants in generally accepted concentrations. It is inactivated in milk by heating to 74°C for 17 seconds. A virus can stay in a cell for a long time in a partially or completely associated state with its genome.

Epizootology. Canine leukemia is diagnosed in many countries around the world. From animals, the pathogen is transmitted by direct or indirect contact: with milk, saliva, blood. The virus spreads quickly if the rules of asepsis and antisepsis are not observed.
As a rule, the disease occurs in all breeds of dogs.

Symptoms and course. The incubation period for leukemia (before the appearance of changes in the peripheral blood) lasts 60-80 days, and for spontaneous - 2-6 years.
Non-specific signs - deterioration in the general condition of the animal, poor absorption of feed, rapid fatigue, progressive emaciation, digestive disorders (diarrhea, constipation, vomiting), weakening of cardiac activity, cyanosis and icterus of the mucous membranes, respiratory disorders, edema, difficulty urinating, abortion.
Specific features leukemia are considered a sharp increase in superficial (prescapular, scapular, parotid, submandibular, popliteal, inguinal) and internal lymph nodes; the appearance of tumor growths in various areas of the body, exophthalmos, enlargement of the spleen and liver. Lymph nodes range in size from a walnut to a chicken egg. When probing, they are painless, slightly mobile, elastic or dense in consistency. Internal lymph nodes are affected more often than superficial ones.

Diagnosis. A veterinarian makes a diagnosis on the basis of epizootological, clinical-hematological, serological and virological studies with mandatory histological examination.
differential diagnosis. It is necessary to exclude diseases accompanied by changes in the composition of the blood similar to leukemia, especially from neoplasms.
It should be borne in mind that many acute and chronic diseases (adenovirosis, some parasitic diseases, metritis, hepatitis, etc.) are often accompanied by significant changes in the blood, which are protective in nature and are defined as a leukomoid reaction of the body, reflecting functional-reactive changes.
Blood changes in leukemia are organic in nature. To exclude these diseases, appropriate microbiological, serological, allergic, histological, scatological, repeated hematological and other studies are carried out.

Treatment poorly designed. Veterinarians often prescribe human antileukemic and antitumor drugs: hexaphosphamide, hydrea, dipine, dopan, mercaptopurine, etc. The dose and course of treatment is determined by the attending veterinarian.

Leukemia is an oncological disease of the hematopoietic and lymphatic systems, which is diagnosed not only in humans, but also in animals. In dogs, blood cancer is very difficult and it is not always possible to save a pet.

Causes of the disease

Leukemia occurs due to anaplasia - the loss of the ability of cells to differentiate and perform their specific duties. When blasts (undifferentiated cells) penetrate into the tissues of the liver and spleen and bone marrow, the processes of oppression of the hematopoietic system and the cessation of the formation of lymphocytes (cells of the immune system) occur.

Factors that provoke the development of blood cancer include the following:

• heredity;
• chemicals;
• ionizing radiation;
• oncoviruses.

It should be noted that leukemias provoked by viruses develop more often in cats than in dogs. However, this etiology cannot be completely discarded. A virus containing RNA can stay in the affected cell for a very long time and show no activity. In the external environment, it dies quickly enough and is sensitive to disinfectants.

Ways of transmission - contact and alimentary. The incubation period can vary from 60 to 80 days.

Breed predisposition

Leukemia can occur in any dog ​​in the age group of 3-8 years. Blood cancer is rare in toy dogs. Much more often it is diagnosed in representatives of large breeds: Labradors, German and Caucasian Shepherds, Rottweilers, Boxers, Argentine Great Danes, St. Bernards.

Main symptoms

There are several types of leukemia, among which the most common are lymphosarcoma and lymphocytic leukemia.

Lymphosarcoma is a malignant neoplasm consisting of young or mature lymphoid cells of the liver, spleen, and lymphatic system. The disease accounts for 80% of all tumors affecting the hematopoietic system.

In lymphocytic leukemia, lymphoid cells are synthesized in the bone marrow and exit through the blood. This pathology is rare in dogs.

At the initial stage, leukemia practically does not manifest itself. The animal may be lethargic, apathetic. The dog refuses to walk and prefers to lie down. Appetite is reduced, due to intestinal disorders, food is not absorbed and digested. Enlargement of the spleen leads to constipation, sometimes alternating with bouts of diarrhea.

Liver damage is characterized by yellowing of the whites of the eyes and skin. Enlarged lymph nodes in the lungs make breathing difficult. It becomes difficult for the dog to overcome even short distances, as he begins to choke and wheeze. Lymph nodes increase in size, but are painless when palpated, which distinguishes leukemia from other pathologies.

The following clinical signs are characteristic of the acute form of the disease:

• internal hemorrhages, bleeding;
• anemia;
• weakness;
• decrease in leukocytes and erythrocytes in the blood;
• spontaneous miscarriages in pregnant bitches;
• deterioration of organs.

In the chronic form, the symptoms are different:

• increased urge to urinate;
• enlarged lymph nodes and spleen;
• intense thirst.

The most dangerous for the dog is the acute form, since the probability of death is very high. It is characterized by an aggressive course, often accompanied by pneumonia, intestinal infections, pustular lesions of the skin.

As a rule, at this stage, the animals can no longer be helped, so the task of the owner is to make the last days of his four-legged pet comfortable.

Diagnostics in the veterinary clinic

To make a diagnosis, the veterinarian will need to conduct laboratory and differential studies, and the sooner the diagnosis is made, the higher the chances of a favorable prognosis.

Laboratory tests include blood tests:

• general - to determine the level of leukocytes and platelets, to detect blastomas;
• biochemical - to obtain information about changes in the activity of internal organs.

Since the symptoms of leukemia are not always specific, differential diagnosis is required, including methods such as ultrasound, biopsy, cell cytology, x-ray

Symptoms in a dog with lymphosarcoma are not specific, therefore, differential diagnosis is required - x-ray, ultrasound, cell cytology, tissue biopsy of the formation.

Method of treatment and prognosis

Treatment for leukemia depends on the form of the disease. Lymphosarcoma is treated quite successfully by chemotherapy, which young animals tolerate successfully. However, older and weakened dogs may simply not survive it.

Therapy is achieved through the use of such modern anticancer drugs as Doxorubicin, Cyclophosphamide, Methotrexate, Dacarbazine.

Successful medical treatment is impossible without the use of cytokines. Chlorambucil has proven itself well, which stops the process of DNA synthesis of cells, which makes it possible to somewhat slow down the rate of spread of leukemia. Also, an effective combination of Prednisolone and Vincristine receives good reviews. These drugs are based on synthetic glucocorticoids that prevent the penetration of leukocytes into the area where inflammatory processes occur.

In extreme cases, surgical methods are used, for example, when, as a result, the tumor affects the organs of the gastrointestinal tract and disrupts their activity or is localized in the skin.

According to statistics, only 15% of individuals can be completely cured of this pathology. In 80% of them, it is possible to achieve complete remission and improve the quality of life. Remission can last from 1 to 2.5 years.

The chronic form, unlike the acute one, is treatable, but only in cases where help is sought no later than 2-3 months after the discovery of leukemia.

With lymphosarcoma of the gastrointestinal tract and other organs, as well as with an acute form of lymphocytic leukemia, the prognosis is unfavorable. Since the acute form does not give the animal a chance for a cure, the only humane way to save him from suffering is euthanasia.

Prevention

It is impossible to prevent the development of leukemia in a dog, but the owner, who notices the changes taking place in the animal’s body in time, is able to prolong his life. A dog diagnosed with leukemia needs good living conditions, a balanced diet and, of course, attention. Animals surrounded by affection and care, it is easier to cope with a terrible disease.

After the treatment, in order to avoid relapses, the pet should be taken to the clinic once a year for a comprehensive diagnosis.

A disease such as cancer can be not only in humans. It is also diagnosed in animals. For example, cancer in dogs is found quite often. There are statistics, based on which, in females, this disease occurs more often than in males. As a rule, this disease occurs in animals whose age is more than 10 years.

Description of the disease

Cancer in dogs is not much different from cancer in humans. The essence of this disease is that the cells begin to mutate. There is a theory that disease occurs as a result of a change in one cell in the body. Then it begins to divide, and the infected area spreads. If the disease is not diagnosed in time, then large groups of modified cells are formed. Further, tumors and metastases form.

If an animal has a disease such as breast cancer, then metastases can spread to bone tissue and lungs.

Gradually, there are more and more infected cells, tumors stop the normal functioning of the organs of the animal's body. They also interfere with the proper functioning of neighboring organs. The next stage in the development of the disease is the decomposition of tumors. This process is characterized by bleeding. From all of the above, the general condition of the dog worsens.

Dogs can have cancer in any part of the body. Mostly old animals are susceptible to the disease. But there are cases of cancer in young dogs. It should be said that cancer is a general characteristic of a disease. Mutation of cells can affect different organs and have its own variety in each individual case. Therefore, a person will not be able to cure cancer in a dog on his own. Home treatment can relieve certain symptoms of the disease. In order to provide significant assistance to the animal, you must contact a veterinarian.

Early diagnosis increases chances of recovery

It should be said that the earlier cancer is detected in a dog (whose photo does not cause positive emotions in anyone), the greater the chances of her recovery. Also, pet owners need to know that there are highly specialized veterinarians who deal with oncological diseases. Therefore, it would be advisable to treat the cancer of the animal by a veterinary oncologist.

It is impossible to predict how long a dog can live with cancer. Since there are many factors that affect this circumstance. First, the age of the dog plays a role. Secondly, an important factor is the stage at which the disease is diagnosed.

If infected cells spread slowly and cancer is detected at the initial stage of the disease, then timely assistance to the animal will ensure its further long life. It also matters which organ is affected by malignant cells. In some cases, surgery may be performed to remove the tumor. Possible treatment options and prognosis for recovery can be determined by a veterinarian after a thorough diagnosis of the dog.

How does the disease manifest itself?

The main problem of diagnosing oncological diseases is that at the initial stage they pass without any signs. The only way to detect cancer is through testing. Therefore, it is necessary to regularly visit the veterinarian with the dog for this. The main tests that will help detect cancer cells are blood and urine tests for biochemistry.

Pet owners should remember that the treatment of the disease is possible only at an early stage of detection. In the event that the distribution is running, not a single veterinarian will help.

More prone to disease bitches

Cancer is common in bitches. This is due to unstable hormonal levels during estrus, childbirth and in the postpartum period. Veterinarians recommend neutering the dog to prevent cancer in the bitch. Especially in cases where the distribution of offspring is not planned.

If the dog gives birth, then after 8 years, when breeding work ends, the animal must also be sterilized. This procedure will protect the dog from this disease.

Cancer in a dog: symptoms and types

Now consider the popular types:

1. Oncological disease of the mammary glands in bitches. can be detected at an early stage. To identify it, the owner of the dog needs to monitor the nipples. Signs of cancer may show up as bumps or lumps on the nipples. They can be detected by feeling the mammary glands. It is also recommended to show the dog to the veterinarian. If the disease progresses and no treatment measures have been taken, then the tumors will be visible visually, and the nipples will also change color. If the tumor is damaged, bleeding will occur.

2. Oncological disease of the dog's uterus. This one is harder to diagnose. Bleeding is a sign of infection. But they can also be the result of other diseases. With uterine cancer, the bitch miscarries or gives birth to dead puppies. The cause of this disease may be drugs, which include hormones. Moreover, cancer cells can appear after one dose of such a remedy.

3. Another cancer risk group are dogs of large breeds. It is almost impossible to visually determine that an animal has cancer. In large dogs, the disease sometimes affects the bones. A sign that an animal has cancer can be changes in walking and running. When these symptoms appear, you should show the dog to a specialist.

4. Oncological diseases of the stomach and intestines can be determined by violations of the body. Namely, a change in stool, vomiting, smell from the mouth. It is necessary to pay attention to the dog's feces. See if there is any discharge in it, such as blood. They will be another sign that the dog has cancer. stomach following - weight loss and appetite.

5. Skin cancer can also be diagnosed. Spotting skin cancer in dogs can be difficult. Especially in animals that have abundant hair. Therefore, it is recommended to regularly examine the dog's skin. It is best to do this while bathing or combing. Oncological skin disease is manifested by the formation of dark spots or seals on it. The color of the spots can vary from red to dark brown.

6. Cancer of the liver in dogs. When the liver is damaged by cancer cells, the mucous membranes of the animal turn yellow. This is due to the fact that bile enters the bloodstream. The consistency of metabolic products also changes. With the spread of cancer cells in the liver and it constantly vomits.

7. Cancer This disease begins with a cough. With further progression, it intensifies, expectoration begins, in which blood secretions and pus are present in saliva.

8. Cancer cells also affect the spleen in dogs. But this type of disease is rare. There are no obvious signs indicating the occurrence of this disease. Usually, the animal shows a deterioration in the general condition, lethargy, apathy, and so on.

9. Cancer of the kidney. It can be difficult to notice kidney cancer, there are practically no external manifestations, especially at an early stage of the disease. At a later stage of the progression of the disease, blood appears in the urine. Also, the dog begins colic, and she whines. The dog's gait undergoes changes due to pain.

Diagnosis

What are the ways to detect cancer in a dog? There is a theory that dogs feel the presence of infected cells in the human body. Allegedly, they can determine by smell whether a person has cancer or not. Perhaps they really manage to feel the oncological disease in the human body.

But for ourselves, it's harder to do that. There is a possibility that dogs feel that their body is infected with malignant cells. But, unfortunately, they cannot inform their owner about this fact.

Diagnostic methods

The main method of detecting the disease at an early stage of dog cancer is a visit to the veterinarian and testing. The doctor orders the animal to donate blood and urine. Based on the results of the tests, namely the presence of any changes in the blood or urine, the veterinarian prescribes repeated laboratory tests for a deeper study.

Then, depending on which organ is suspected of being affected by malignant cells, a further examination is carried out. Namely, computer diagnostics of a specific organ is assigned. It can be done through ultrasound, MRI and other methods. When a tumor is found, the veterinarian takes a puncture of the tissue in order to determine whether it is malignant or not.

Treatment

It should be said that the treatment of cancer in dogs must be entrusted to a specialist. You should not self-medicate or listen to any people who do not have special education and proper qualifications in this area.

Self-medication is not recommended due to the fact that the disease is individual in nature, for example, there is squamous cell carcinoma in dogs. Many have not heard of this. Only a veterinarian can identify the features of the disease, based on the results of tests and other studies.

Chemotherapy is used to treat malignant cells in dogs. The next step is to remove the tumor. It is not possible to do this in all cases of the disease. For example, if the brain is affected, then surgery cannot be done. If the operation to remove the tumor has taken place, then a second session of chemotherapy is prescribed.

Nutrition for Cancer

It is necessary to provide the dog with proper nutrition. The diet should not include spicy and fatty foods. Such a diet should be maintained for a long time. It should be said that fatty foods are not recommended for consumption by a healthy pet.

It must be remembered that during the rehabilitation period it is necessary to create favorable conditions for the dog. Namely, to ensure regular walking and cleanliness. It is necessary to ensure that the dog does not come into contact with stray animals, since the body is weakened after the course of treatment and it will be better to exclude any sources of infection.

put to sleep

There are times when cancer in dogs progresses very quickly and the treatment provided does not give positive results. In this case, the owner of the animal should consider putting him to sleep, as this option will save him from suffering.

If a person sees that the ongoing treatment does not alleviate the suffering of the animal, then he is recommended to talk with the veterinarian about whether it is worth continuing, whether there is a chance that the dog will recover. If the attending veterinarian says that the chances of the dog are zero, then the best way out of the situation is to euthanize the pet.

Thus, the owner of the animal will save him from excruciating pain. If death is inevitable due to cancer and the dog is suffering, then euthanasia should be resorted to.

Seek another specialist

There is an option that the veterinarian cannot help the animal, and the owner of the dog is confident in her recovery. Then it is recommended to contact another specialist. Perhaps he will select a different treatment regimen, and the dog will get better.

Conclusion

Now you know how cancer in dogs manifests itself. We have described the symptoms and treatments. Unfortunately, this disease is very serious. Therefore, if you suspect that the animal has cancer, then immediately contact a qualified specialist.

Leukemia in dogs refers to malignant cancerous pathologies that affect the blood and lymph of a pet. With late diagnosis, this form of oncological disease can lead the dog to death. The article will discuss what are the causes and characteristic symptoms of this disease, as well as methods for its treatment and prognosis for the recovery of animals diagnosed with blood cancer.

In veterinary medicine, leukemia is commonly understood as an oncological disease that progresses in the circulatory and lymphatic system of a dog and proceeds in a malignant form. Generally speaking, the disease provokes destructive changes in the functioning of the bone marrow in a dog. It is he who is responsible in the body for hematopoietic processes.

When such a neoplasm appears in the body of a dog, the cells mutate, after which they cease to cope with their specific duties. Over time, the blasts enter the tissues of the liver and bone marrow. As a result, the process of hematopoiesis is completely disrupted, and the main defenders of the dog's immunity - lymphocytes - stop being produced. The animal becomes vulnerable to viral infections, and its organs cease to function fully.

Causes

The main factors due to which pathology occurs include:

1. genetic predisposition. An animal may be vulnerable to blood cancer while still a puppy if there were any defects in the cells of its parents.
2. Ionizing radiation. Radioactive particles are not uncommon in the rapidly advancing world of technology and nuclear technology.
3. Chemical substances. They can affect the dog through food or hygiene products.
4. oncogenic viruses. The theory proving that viruses can cause oncology appeared in veterinary medicine not so long ago, but has already found supporters.

Varieties and forms of the disease

Experts distinguish two types of leukemia:

1. Lymphosarcoma. Diagnosed in 75% of cases, it leads to severe damage to the lymphatic system and liver.
2. Lymphocytic leukemia. It is extremely rare in dogs, with it lymphoid cells are synthesized in the bone marrow, then entering the bloodstream. Among veterinarians, this disease is also called leukemia.

In addition, doctors divide lymphoblastic leukemia according to the forms of the course, depending on the clinical symptoms and the type of cells that provoke the pathology:

1. Acute leukemia. Immature blastomas actively invade the bone marrow, gradually crowding out healthy cells.
2. Chronic form. Neoplasms located in the bone marrow consist entirely of mature blastomas, the number of leukocytes in the blood increases significantly.

Statistical data show that medium and large breeds of dogs, such as Caucasian Shepherd Dogs, St. Bernards, Dobermans, Rottweilers, are prone to leukemia. In miniature individuals, pathology practically does not occur. An important factor is the age of the dog, those pets that have reached 5-6 years of age are especially vulnerable.

Symptoms

At the very beginning of the development of the disease, its symptoms practically do not appear. The animal becomes lethargic and lethargic, ceases to like long walks, preferring to just lie down or sleep. Gradually, the dog loses its appetite, an attentive owner may notice that there are pieces of food that are poorly digested and not assimilated by the body in the feces. Constipation and diarrhea occur, which indicates dysfunction of the gastrointestinal tract. In particular, an enlarged spleen in a dog leads to constipation.

At the next stage, the main life support systems of the dog are involved in the pathological process. This provokes symptoms such as yellowing of the skin and whites of the eyes, which indicate problems with the liver, as well as heart failure, which makes the dog quickly tired while walking. Enlargement of the lymph nodes in the lungs leads to severe shortness of breath after running or climbing stairs.

In advanced cases of leukemia, strongly swollen lymph nodes are clearly palpable in a four-legged friend. Moreover, palpation itself does not cause pain to the dog, which makes it possible to differentiate leukemia from other ailments. The above symptoms refer to the general clinical picture of the disease, however, they may vary depending on each specific form of pathology development.

Acute leukemia manifests itself in such signs:

• internal bleeding caused by the fact that the blood ceases to clot normally;
• a significant decrease in the protective functions of immunity;
• low levels of platelets and leukocytes in the blood;
• anemia and subsequent complete organ failure.

To be frank, an animal with acute leukemia will not live long. The prognosis is the most deplorable and excludes any therapy, so the owner must make the rest of the dog's life as comfortable as possible.

Chronic leukemia can be identified by the following symptoms:

• frequent urination;
• an increase in the size of the lymph nodes and spleen;
• constant desire to drink water;
• anemia.

The owner, when the first alarming bells appear in the dog, which may indicate blood cancer, should immediately contact the veterinary clinic for help.

Diagnostics

Experts are convinced that early diagnosis of leukemia greatly facilitates the treatment of pathology. To differentiate the diagnosis, such types of studies as general clinical and biochemical blood tests are used. Moreover, with lymphosarcoma, the composition of the pet’s blood does not change significantly, but a highly experienced doctor may notice the appearance of “immature” cells in it. In severe cases, a decrease in the level of leukocytes and platelets in the blood is significant, which simplifies the diagnosis. Lymphocytic leukemia, on the contrary, can be determined by the fact that the number of leukocytes exceeds the permissible norm.

In addition, additional diagnostics of the dog with the help of x-rays and ultrasound, cytological examination of the affected cells and histological analysis of the lymph node, which is swollen, is acceptable. They are used for all types of pathology.

Treatment of the disease

It should immediately be noted that a complete cure is possible only in 15-20% of cases. But this is not a reason to despair, because medicine does not stand still and every day doctors make every effort to improve the prognosis for the recovery of pets from leukemia. Therapy lends itself only to chronic forms of the disease, acute leukemia is incurable and probably leads to the death of the animal. Moreover, the goals of therapeutic intervention are not so much to cure the dog, but rather to prolong his life as much as possible, eliminating the process of the appearance of new tumors and achieving stable remission.

Drug treatment involves the use of such effective drugs as cytotoxins. They belong to:

1. Prednisolone and Vincristine. They are based on synthetic glucocorticoids, which prevent leukocytes from entering the area where inflammatory processes occur.
2. Chlorambucil. It disrupts the process of DNA cell synthesis, preventing chaotic cell division, which makes it possible to somewhat slow down the rate of spread of leukemia throughout the pet's body.

In addition to taking the above drugs, the attending physician prescribes chemotherapy for the animal. This procedure copes quite well with various oncological diseases and is well tolerated by dogs. However, it must be borne in mind that too weakened and elderly dogs may simply not survive it.

In European countries, experiments are being conducted in which they try to transplant bone marrow into dogs. But their effectiveness has not yet been proven, and the cost of such surgery will be extremely high. As for the prognosis, we repeat, acute leukemia is not treatable, and in the chronic form, a favorable outcome is possible only in 25% of cases, and this depends on how early the pathology is detected.

Finally, I would like to say that the owners are able to prevent the development of this terrible disease in dogs. You just need to carefully observe the animal, noticing changes in its behavior and health. If any unusual symptoms are noticed, it is necessary to take the dog to the doctor immediately. After making a diagnosis, strictly follow the recommendations for the implementation of the treatment regimen prescribed by the doctor. And most importantly, surround the dog with affection and care, so he can quickly cope with such a serious illness as leukemia.