INTERLEUKIN-2 AND LEUKEMIA

Leukemia has been treated with chemotherapy for the past 40 years with only moderate success. A growing body of evidence suggests that by au gmenting the immune system more effective results may be obtained. Thi s is highlighted by T cell reinfusions resulting in durable remissions in patients with chronic myelogenous leukemia who have relapsed after an allogeneic transplant. Interleukin-2 is the primary growth factor for T lymphocytes and is a stimulator of natural killer cell activity. It has now been shown that a limited number of otherwise refractory l eukemias can be effectively treated with interleukin-2. However, there remains a lack of correlation between the biologic and clinical effec ts of interleukin-4. The clinical activity of interleukin-a appears to be greatest in myeloid leukemias. A variety of dose schedules and rou tes of administration make it difficult to determine if interleukin-2 given to patients in clinical remission is of benefit. Large randomize d studies are necessary to explore the role of interleukin-2 in leukem ia.