Chronic lymphocytic leukemia in cats is primarily a T helper cell disease

Chronic lymphocytic leukemia (CLL) in cats shares many similarities with its human counterpart but also has significant differences. In marked contrast to people, CLL in cats is primarily a T-lymphocyte proliferation. The T helper cell proliferations seem to be most common in cats with CLL. Immunophenotyping and assessment of clonality by molecular genetic analysis are newer adjunctive tools in veterinary medicine that are useful in the characterization and diagnosis of CLL in cats. The clinical presentation, typical hematologic findings, diagnosis, course of disease, prognosis, and therapy of CLL in cats are ptresente and discussed.