Long-term follow-up of patients with multiple myeloma treated with total body irradiation-Melphalan conditioning.

Abstract

Since a study published in 2002 showed a survival advantage of melphalan-only conditioning for stem cell transplantation (HSCT) over melphalan-total body irradiation (mel-TBI) in patients with multiple myeloma (MM), most centers abandoned mel-TBI. Mel-TBI causes more early toxicity and is more complicated to administer, but we speculated it may result in longer term survival with radiation as an independent treatment modality. Therefore, we analyzed the long-term outcome of patients with MM who received mel-TBI as part of conditioning at our center. From 1995 to 2013, 50 patients with MM underwent autologous HSCT at Tulane University Medical Center using mel-TBI conditioning. We used Kaplan-Meier survival analysis and compared our patients with data available from the Louisiana Tumor Registry. The mean survival of our patients was 70.98months from time of transplant and 84.2months from time of initial diagnosis. No differences were observed according to gender, ethnicity, or age at transplant. The expected median survival in a population-based registry (matched for age and year of treatment) was 27months (P<.001). Total body irradiation in conjunction with melphalan as conditioning is feasible and can lead to long-term survival. More research is necessary to determine which patients benefit most. Mel-TBI should also be explored in conjunction with immunotherapy.