LGL leukemia displays a chronic clinical course. Recommendations regarding therapy are similar for both subtypes. Indications for treatment include 1) severe neutropenia (ANC <500 mm3); 2) neutropenia (ANC <1500mm3) with symptomatic recurrent infections; 3) symptomatic or transfusion-dependent anemia and 4) associated autoimmune conditions requiring therapy, most often rheumatoid arthritis.