Early versus delayed autologous stem cell transplantation (SCT) results in comparable overall survival in patients with multiple myeloma (MM) who receive alkylator-based therapies. It is not clear whether this paradigm holds true in the context of new therapies, such as immunomodulatory drugs (IMiDs).
The authors studied 290 patients with untreated MM who received IMiD-based initial therapy, including 123 patients who received thalidomide-dexamethasone (TD) and 167 patients who received lenalidomide-dexamethasone (LD) induction before SCT. Patients who underwent a stem cell harvest attempt were considered transplantation-eligible and were included. SCT within 12 months of diagnosis and within 2 months of harvest were considered early SCT (n = 173; 60%). SCT >12 months after diagnosis was considered delayed SCT (n = 112; 40%).
In the delayed SCT group, 42 patients had undergone SCT at the time of the current report, and the median estimated time to SCT was 5.3 months and 44.5 months in the early SCT and delayed SCT groups, respectively. The 4-year overall survival rate from diagnosis was 73% in both groups (P = .3) and was comparable in those who received TD (68% vs 64%, respectively) and those who received LD (82% vs 86%, respectively) as initial therapy. The time to progression after SCT was similar between the early and delayed SCT groups (20 months vs 16 months; P value nonsignificant).
The current results indicated that, in transplantation-eligible patients who receive IMiDs as initial therapy followed by early stem cell mobilization, delayed SCT results in similar overall survival compared with early SCT. It is noteworthy that an excellent 4-year survival rate of >80% was observed among transplantation-eligible patients who received initial therapy with LD regardless of the timing of transplantation.