Systemic interleukin-2 therapy in children with progressive neuroblastoma after high dose chemotherapy and bone marrow transplantation.

Two children with active metastatic neuroblastoma after high dose chemotherapy and bone marrow transplantation (BMT) received a high dose continuous infusion of interleukin-2 (IL2) 120 days after an autologous BMT for patient 1 and 90 days after an allogeneic non T cell-depleted BMT for patient 2. Usual side effects of IL2 therapy were observed without life-threatening complications or any major hematological toxicity. The reactivation of graft-versus-host disease during IL2 infusion in patient 2 was the major BM-related complication but it improved with IL2 interruption and corticosteroids. IL2 induced a complete remission (9+ months) in patient 1 with the disappearance of bone metastases and local tumor but patient 2 progressed after cessation of therapy. Patient 1 presented with a large excess of circulating NK cells in the period after autologous BMT and IL2 induced a preferential outgrowth of this lymphocyte subset.