High-dose chemotherapy with melphalan and autologous hematopoietic stem cell transplantation (HSCT) is considered standard treatment for patients with multiple myeloma. While autologous HSCT may induce remission in patients resistant to standard chemotherapy, and has been shown to lead to long-lasting disease control in a subgroup of patients, the procedure is not curative. Given enough time and in the absence of a competing cause of death, all patients eventually relapse after auto-HSCT.