Lymphoid leukemias Flashcards
What are lymphoid leukemias
Lymphoid leukemias are due to neoplastic proliferation of lymphoid cells in the bone marrow
- in many cases, there will be circulating neoplastic cells
Lymphoid leukemias are the most common form of leukemia in cats, and there is a strong association with FeLV infection
There are two primary forms of lymphoid leukemias:
- acute lymphoblastic leukemia
- chronic lymphocytic leukemia
What are the cause of clinical signs in acute lymphoblastic leukemia
Clinical signs may relate to bone marrow disturbances (e.g., anemia, thrombocytopenia) and/or to systemic infiltration of neoplastic cells into organs (e.g., causing hepatomegaly, splenomegaly, …)
What are the hematological changes associated with acute lymphoblastic leukemia
Hematological changes are highly variable:
- there may be massive leucocytosis and lymphocytosis with large numbers of circulating blasts
- or there may be a leucopenia with an almost absolute absence of circulating white cells
Neutropenia, anemia and/or thrombocytopenia are seen commonly
What is the treatment and prognosis for acute lymphoblastic leukemia
Response is universally poor and the prognosis is grave
Therapy with a multi-drug protocol including cytosine arabinoside may be attempted
What are the cause of clinical signs in chronic lymphocytic leukemia
Chronic lymphocytic leukemia is probably less common than ALL in cats
There is a mature lymphocytosis (with or without cytopenia of one of the other blood cell lines) and a predominance of mature lymphocytes in the bone marrow aalso
- circulating mature lymphocytosis has to be differentiated from physiological lymphocytosis (which is more commonly seen in immature cats) and inflammatory lymphocytosis
How would yoou make a diagnosis of chronic lymphocytic leukemia
Lymphocytosis may be profound (e.g., in excess of 30-60 * 10^9/l and a bone marrow aspiirate helps confirm the diagnosis
Where there is organ involvement (GI tract, liver, spleen) biopsy may reveal a heavy infiltrate with maturev lymphocytes
- immunostaining may also help confirm the diagnosis
What is the prognosis and treatment for chronic lymphocytic leukemia
The prognosis for CLL is better than for ALL
- it tends to be a more slowly progressive disease
There may be positive response to chemotherapy
- there is evidence that this disease responds favorably to prednisolone and chlorambucil
