Canine Leukemia

Leukemia is a cancer of the blood and causes a large increase of white blood cells (leukocytes) either in the circulation or in the bone marrow. Leukemia can come from bone marrow or from lymph node cells.

Acute lymphoid leukemia (ALL) develops rapidly. Symptoms include loss of appetite, swelling of the lymph nodes, panting, pica (obsessive eating of non-food items such as clay, dirt, etc.), fever, bleeding, vomiting, pale gums, anxiousness.
Infections will occur and are triggered by not having enough healthy, fully functional white blood cells. That as a result can cause rapid death if not treated immediately.

Contrary to humans, where acute leukemia is one of the most common childhood cancers, this cancer is mostly reported in mature dogs, not puppies or young animals.

Treatment for acute leukemia is similar to chronic leukemia but success rates are very poor. Most dogs live only a very short time after the disease has been diagnosed.

Chronic leukemia (CLL or CML) develops over time. The number of white blood cells increases less rapidly and the disease gets worse slowly over time. Again, due to the increased number of white blood cells the body cannot be protected properly from viruses or infections and the immune system will be suppressed. In addition a failure of the bone marrow and infiltration of cancer cells into organs will occur.

Chronic leukemia starts in the bone marrow but will spread to the blood, liver, spleen, lymph nodes, central nervous system, and other organs. It does not usually form a solid mass or tumor.

Leukemia is diagnosed by examination of the bone marrow and blood.

Treatments are done to reduce the number of white blood cells and lead normally to a temporary remission. In most cases the number of white cells will increase again, and as soon as the critical number is reached, treatments can be repeated. This remission – re-treatment can be done many times. Unfortunately, sooner or later, depending on individual cases, the chronic leukemia will turn into acute leukemia.

Some dogs have been known to live several months or even years until the acute leukemia takes over. In that case the veterinarian will talk about a “blastic crisis”.

See also our article about >>Feline Leukemia