Total Marrow Irradiation as Part of Autologous Stem Cell Transplantation for Asian Patients with Multiple Myeloma

To compare the outcomes of melphalan 200 mg/m² (HDM200) and 8 Gy total marrow irradiation (TMI) delivered by helical tomotherapy plus melphalan 140 mg/m² (HDM140 + TMI 8 Gy) in newly diagnosed symptomatic multiple myeloma (MM) Asian patients. Between 2007 and 2010, nine consecutive myeloma patients who were scheduled to undergo autologous stem cell transplantation (ASCT) were studied. The patients received three cycles of vincristine-adriamycin-dexamethasone (VAD) regimen as induction chemotherapy, and if they had a partial response, peripheral blood stem cells were collected by dexamethasone-etoposide-cyclophosphamide-cisplatin (DECP). In arm A, six patients received the HDM200. In arm B, three patients received HDM140 + TMI 8 Gy. In arm B, the neutropenic duration was slightly longer than in arm A (P = 0.048). However, hematologic recovery (except for neutrophils), transfusion requirement, median duration of hospitalization, and the dose of G-CSF were similar in both arms. The median duration of overall survival and event-free survival was similar in the two arms (P = 0.387). As a conditioning regiment, HDM140 + TMI 8 Gy provide another chance for MM Asian patients who were not feasible for HDM200.