Real-life data on safety and efficacy of autologous stem cell transplantation in elderly patients with multiple myeloma

Autologous stem cell transplantation (ASCT) is still debatable in treatment of patients over 65years with multiple myeloma (MM). We performed aretrospective analysis of newly diagnosed MM patients who underwent ASCT between January 2010 and July 2016. A non-transplanted group with similar clinical characteristics, aged 65-70years old, diagnosed and treated in the same timeline was used for comparison. We analyzed a total of 155 patients, 132 of which underwent ASCT (65years, n=103, median 56years; >65years, n=29, median 67years) and 23 non-transplanted (median 68years). Conditioning consisted of melphalan 200mg/m(2) (MEL200) in younger patients and melphalan 140mg/m(2) (MEL140) in half of elderly patients. Stratifying by age, there were no statistically significant differences concerning transplant-related myelotoxicity and non-hematopoietic toxicity; however, elderly patients conditioned with MEL200 had higher needs of transfusional support and more days of intravenous antibiotics. Those patients also had higher needs of transfusional support, higher grade of mucositis (p=0.028), and more days of intravenous antibiotics (p=0.019) than the elderly transplanted with MEL140. Global transplant-related mortality was 3.8%. Survival was not influenced by age. Non-transplanted elderly patients had comparable disease features, and induction response was similar in both groups (before ASCT in the transplanted cohort). Survival of transplanted elderly patients was superior to non-transplanted (OS, 59months vs 30months, p=0.037; EFS, 45months vs 27months, p=0.014). Selected elderly patients when transplanted have similar disease response and survival as younger patients. A higher dose of melphalan has more toxicity, but it is globally a well-tolerated procedure.