Effective and safe interferon treatment for Japanese patients with chronic myelogenous leukemia relapse after bone marrow transplantation. The Nagoya Blood and Marrow Transplantation Group.

The purpose of this study was to assess the efficacy and safety of interferon (IFN) treatment in patients with a relapse of chronic myelogenous leukemia (CML) after bone marrow transplantation in Japan. Accordingly, we retrospectively analyzed the results obtained from 8 patients treated with IFN by the Nagoya Blood and Marrow Transplantation Group. One of 3 patients with hematologic relapse and all 5 patients with cytogenetic relapse achieved complete cytogenetic response (CCR). The median time to achieve CCR was 8 months (range, 3-16 months). One patient relapsed 9 months after starting IFN and died of blast crisis. CCR was maintained for a median duration of 47 months (range, 9-79 months) in the remaining 5 patients. The median duration of survival of these 5 patients after starting IFN was 58 months (range, 12-89 months). At the time of this report, 2 patients who did not attain CCR have survived for 81 months and 142 months after starting IFN, respectively. During IFN treatment, 1 patient showed a transient deterioration of chronic graft-versus-host disease, and no treatment-related deaths were observed. These results suggest that treatment with IFN for CML patients who relapse after bone marrow transplantation is effective and safe. A prospective study to compare IFN with donor lymphocyte infusion is necessary to establish the optimal strategy for the treatment of CML patients who relapse after bone marrow transplantation.