Chronic Leukemia in Dogs

Leukemia in dogs is a type of cancer of the blood that's characterized by a proliferation of white blood cells in the bone marrow or the blood. This cancer is caused by a mutation in the bone marrow.

Types of Leukemia in Dogs

The word "leukemia" means "bad blood," and a dog with leukemia has a large number of white blood cells in his bloodstream or bone marrow. The mutation that causes leukemia alters the structure of the bone marrow and causes it to produce cancerous cells. Leukemia in dogs can be classified into two types: acute leukemia and chronic leukemia.

While acute leukemia is characterized by a sudden onset, the proliferation of white blood cells in pets suffering from chronic leukemia is gradual.

Chronic Leukemia in Dogs

There is a gradual increase in the number of white blood cells in dogs suffering from chronic leukemia. These cells can no longer protect the body from infections and viruses. Hence, the disease progresses at a slower pace than acute leukemia. There are two types of chronic leukemia that strike dogs, depending on the type of white blood cell that's affected by the disease. They include chronic myeloid leukemia (CML) and chronic lymphocytic leukemia (CLL)

Symptoms of Chronic Leukemia in Dogs:

  • Excessive bruising
  • Excessive bleeding
  • Development of pinprick bleeds
  • Failure of the immune system
  • Failure to resist infections such as diarrhea, pneumonia, tonsillitis or opportunistic infections
  • Anemia caused by deficiency of red blood cells
  • Fever
  • Chills
  • Nausea
  • Fatigue
  • Loss of appetite and weight
  • Lethargy 
  • Seizures


The vet will carry out a number of tests to confirm the diagnosis of chronic leukemia in your pet, in addition to a physical examination and a complete medical history. These tests include a complete blood count test, urine analysis, X-rays of the chest, ultrasound of the abdomen, bone marrow aspirate test, biochemical profile test, aspirate of lymph nodes and organs in the abdomen with a fine needle, and the reticulocyte count test.


The treatment of chronic leukemia is aimed at reducing the number of white blood cells present in the blood. This causes a temporary remission of the cancer for a certain duration, after which there is a proliferation of the cells. The treatment has to be repeated every time the white blood count reaches a critical number, to ensure that the cancer remains in remission.

This ultimately results in acute leukemia or a blastic crisis. Therapy consists of chemotherapy, blood transfusions to stabilize your pet and antibiotics to help him fight infections.


Since your dog's immune system has failed due to the proliferation of white blood cells, you must ensure that he isn't afflicted by secondary infections. You should feed your pet a nutritious diet and ensure that he doesn't lose too much weight. Regular blood tests are essential to monitor the effectiveness of the treatment, along with physical examinations performed by the vet.

The prognosis for chronic leukemia in dogs is good. Pets with this form of cancer can live for several years until the chronic leukemia becomes acute in nature.