Leukemia is a progressive, malignant disease of the blood-forming organs characterized by a large increase in the number of leukocytes (white blood cells) in the circulation or bone marrow. Leukemias were originally termed acute or chronic based on life expectancy but now are classified according to cellular maturity. Acute leukemias consist of predominately immature cells; chronic leukemias are composed of more mature cells. Leukemias are further classified according to the cell of origin, such as lymphoblastic, chronic lymphocytic, myelogenous, acute myelogenous, granulocytic, multiple myeloma, erythroleukemia, and so forth.
Chronic lymphocytic leukemia (CLL) in dogs and cats shares many similarities with its human counterpart but also has significant differences. Dogs with acute leukemia only live a very short period of time after the diagnosis has been made, while those with chronic leukemia have been reported to live from several months to years. Signs of acute lymphoid leukemia include anemia, fever, bleeding, loss of appetite, swelling of the lymph nodes, anxiousness, panting, pica, vomiting, pale gums, weight loss, shifting limb lameness, and gait incoordination. Clinical examination reveals enlargement of the liver and spleen.
Chemotherapy is aimed at restoring the blood cell counts to normal range, and response to treatment is monitored by periodic tests. Once remission is achieved, maintenance therapy is continued in order to keep the white blood cells counts within the normal range.
- Canine and Feline Geriatric Oncology. Alice Villalobos, Laurie Kaplan
- Clinical Immunology of the Dog and Cat. Michael J. Day