Survival outcomes following autologous stem cell transplant with melphalan 140mg/m2 versus 200mg/m2 preparative regimens in patients with multiple myeloma

The standard preparative regimen for autologous stem cell transplant (ASCT) in multiple myeloma (MM) is 200 mg/m(2) of intravenous melphalan; however, a dose of 140 mg/m(2) is often used when concerns exist related to patient age, performance status, organ function, and other factors. It is unclear whether a lower dose of melphalan impacts post-transplant survival outcomes. We performed a retrospective review of 930 patients with MM who underwent ASCT with 200 mg/m(2) versus 140 mg/m(2) melphalan. On univariable analysis, no difference in progression-free survival (PFS) was observed, however, an overall survival (OS) benefit was observed in patients receiving 200 mg/m(2) melphalan (p = 0.04). Multivariable analyses showed patients receiving 140 mg/m(2) faired no worse than those receiving 200 mg/m(2). While a subset of younger patients with normal renal function may achieve superior OS with a standard dose of 200 mg/m(2) melphalan, these findings suggest an opportunity to individualize the ASCT preparative regimen to optimize outcomes.