Leukemia in Dogs

Overview of Canine Leukemia

Leukemia is a type of cancer that results from the proliferation of cancerous blood cells in the bone marrow. The cause of leukemia in dogs is unknown, although in humans, exposure to certain chemicals, treatment with chemotherapy drugs, and radiation therapy have all been implicated in causing leukemia.

Leukemia can be classified in many different ways, based on the specific type of blood cell which is involved. The most common form of leukemia seen in cats and dogs is lymphocytic leukemia, because of the involvement of lymphocytes, which are a type of white blood cell. Lymphocytic leukemia can be further broken down into acute (sudden onset) and chronic (long term illness) forms.

The impact of leukemia on your pet can vary with the form of the disease. The different forms have differing clinical presentations and each form carries a different prognosis for your dog.

What to Watch For

Signs of Leukemia in Dogs may include:

Diagnosis of Leukemia in Dogs

Treatment of Leukemia in Dogs

Home Care and Prevention

Give all medications as directed. Many patients with leukemia are predisposed to secondary infections due to a compromised immune system. Exposure to animals outside of the household should be minimized as much as possible.

There are no specific measures to prevent leukemia in your dog.

In-depth Information on Leukemia in Dogs

The acute form of lymphocytic leukemia is called acute lymphoblastic leukemia, or ALL. This form is more common in German shepherds and large breed dogs of any age. Pets with ALL are generally very ill, and begin to show clinical signs of illness fairly suddenly. Patients with ALL will often have a fever.

The chronic form of lymphocytic leukemia is called chronic lymphocytic leukemia, or CLL. This disease is usually seen in dogs older than 10 years, with no breed predisposition. Pets with CLL often have vague signs of illness that can be present for months to years before a diagnosis is made. The most common complaints include weight loss and lethargy, although the aforementioned signs can also be present.

Based on the clinical signs alone, leukemia can mimic a multitude of disease processes. The appropriate laboratory findings are crucial to making a diagnosis. However, other conditions that may cause similar clinical signs include:

In-depth Information on Diagnosis

In-depth Information on Therapy

Therapy and prognosis for the different types of leukemia are quite different. ALL tends to have a very poor prognosis, and affected animals often succumb to secondary infection. Although the cancer cells may respond to therapy, the presence of secondary complications often creates severe illness. In addition to being at risk for infection, these patients are often profoundly anemic, may develop life threatening bleeding disorders, and can even suffer from neurologic disease such as seizures and strokes. Unfortunately, pets with ALL often die within days to months of diagnosis. Animals with CLL, on the other hand, can do quite well and will often live several years with appropriate treatment. The mainstays of therapy are listed below.

Follow-up Care for Dogs with Leukemia

Optimal treatment for your dog requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your pet does not improve over the expected time frame. Administer all prescribed medications as directed. Alert your veterinarian if you are experiencing problems treating your dog.

Follow-up will include weekly evaluations of the CBC to monitor red and white blood cell counts and platelet levels. This is one important way to measure response to treatment. Additional bloodwork, such as biochemical profiles may also be needed, depending on the results of the original profile.

Just as important as the lab results, physical examination by your veterinarian on a weekly basis is imperative until the disease process is considered to be stable or in remission. Your veterinarian will monitor weight, body condition, and temperature and palpate lymph nodes and internal organs to assess their size.

Repeat x-rays or ultrasound exam may be indicated to track changes in organ size as well.

Once your pet is stable, less frequent exams will be needed, but close contact with your veterinarian is required for the life of your dog.

Monitor your dog at home for signs of lethargy, continued weight loss, anorexia, and general weakness. Learn how to check your pet’s temperature with a rectal thermometer and call the veterinarian if a fever is present. A temperature greater than 102.5 degrees Fahrenheit in a resting animal is abnormal. Remember that body temperature may rise with exercise and a warm environment.