Sensitivity of secondary acute myeloid leukemia relapsing after allogeneic bone marrow transplantation to immunotherapy with interferon-alpha 2b.

A patient with acute myeloid leukemia secondary to therapy of choriocarcinoma underwent T cell non-depleted allogeneic bone marrow transplantation from an unrelated donor in first untreated relapse. Persistent/relapsed leukemia 4 months after transplantation did not respond to cessation of cyclosporine. Due to logistic difficulties in obtaining donor leukocytes, she was treated with interleukin-2 and interferon-alpha 2b. Although the interleukin could be administered for a short period only, the interferon was continued for 4 months. Interferon was stopped when limited chronic graft-versus-host disease developed, but was followed by extramedullary and early marrow relapse. Reinstitution of interferon resulted in the development of scleroderma-like extensive chronic GVHD and remission. Interferon was given for 5 months. GVHD improved slowly with treatment, but scleroderma-like changes still persist. The patient is alive with no evidence of disease and a Karnofsky score of 90% 41 months after relapse and 26 months after stopping cyclosporine. We conclude that cytokines alone may occasionally result in a durable response of acute leukemia relapsing after allografting, and should be considered in patients with a low tumor burden if it is difficult to obtain donor cells.