Autologous stem cell transplantation for elderly patients with newly diagnosed multiple myeloma in the era of novel agents

Background: High-dose therapy (HDT) with autologous stem cell transplantation (ASCT) is considered the standard of care for multiple myeloma (MM) patients <65 years. Safety and outcome of ASCT for patients >65 years is currently uncertain, especially since the introduction of novel agents for induction and maintenance therapy. Furthermore, there are no conclusive data available on risk assessment in elderly patients treated with HDT.

Patients and methods: We retrospectively analyzed 202 patients ≥60 years with newly diagnosed MM who underwent ASCT at our institution. Patients were stratified by age into three groups (60-64, 65-69 and 70-75 years). For safety assessment, we compared data about hospitalization, hematopoetic reconstitution and early mortality. Remission before and after ASCT was analyzed according to age and application of novel agents. Event-free (EFS) and overall survival (OS) were analyzed to identify impact of age, remission before/after ASCT and maintenance therapy as well as ISS score and cytogenetic aberrations on outcome in elderly patients.

Results: The assessment of safety, remission before/after ASCT as well as EFS and OS showed no significant differences between the three groups (median EFS: 60-64 years: 27 months; 65-69 years: 23 months; 70-75 years: 23 months; median OS: not reached). Patients receiving novel agents as part of induction therapy achieved significantly higher nCR + CR rates than patients treated without novel agents. In Cox regression analysis, ISS and cytogenetics as well as remission after ASCT had the highest prognostic impact on EFS and OS. Maintenance therapy was associated with longer EFS in uni- and multivariate analyses.

Conclusion: ASCT is feasible for selected patients >65 and >70 years without increased mortality. Age at transplantation has no prognostic significance on outcome after ASCT. Novel agents during induction therapy and maintenance therapy improves outcome of older patients eligible for ASCT. ISS and cytogenetic analysis should be carried out routinely for risk assessment.