Generation of autologous immunity to acute myeloid leukaemia and maintenance of complete remission following interferon-alpha treatment

Interferon-alpha (IFN-alpha) is established as part of the treatment for ch ronic myeloid leukaemia, although its precise mode of action remains largel y unknown. Its use in acute myeloid leukaemia (AML) has been limited. We ha ve previously documented autologous cytolytic activity against AML blasts i n patients after autologous bone marrow transplantation. Here we present a patient with poor-risk AML who relapsed from first complete remission (CR) and was unwilling to undergo high-dose chemotherapy with stem cell rescue. In second chemotherapy-induced on, the patient had no evidence of antileuka emia cytolytic activity in an in vitro assay, and she commenced IFN-alpha ( Roferon). She subsequently developed high levels of leukaemia-specific cyto toxicity, and has remained in second CR for two years. These findings suppo rt the use of IFN-alpha in patients with poor-risk AML, and suggest that on e mechanism of action may be immunological.