The most common type of leukemia is chronic lymphocytic leukemia. It strikes about 10,000 people per year. The next most common type is, acute myeloid leukemia, affecting about 8,000 cases a year, then chronic myeloid leukemia about 5,000 cases per year and then acute lymphocytic leukemia with 4,000 cases per year. The course of treatment for the different leukemias range from watchful waiting to bone marrow transplantation. Additionally, there are some new, targeted therapies, Rituxan and Gleevec.