Efficacy of reduced dose melphalan conditioning for multiple myeloma patients undergoing autologous stem cell transplantation: in the era of combined induction with novel agents

Özet

Aim: Melphalan 200 mg/m2 (MEL 200) is known as the standard conditioning regimen for Multiple Myeloma (MM) patientsin autologous stem cell transplantation (ASCT). Most of the studies showing the superiority of MEL 200 versus melphalan 140mg/m2 (MEL 140) were performed in the era of conventional chemotherapies. However, today, several novel agents such asproteasome inhibitors, immunomodulatory agents have been introduced in MM treatment algorithms. There is limited data onthe impact of this dose reduction on progression-free survival (PFS) or overall survival (OS). The present study compares MEL140 and MEL 200 conditioning for ASCT in patients treated with combination therapy of bortezomib-containing induction.Material and Method: Results of 84 MM patients who underwent ASCT at our center between 2010 and 2018 were analyzedretrospectively.Results: In the MEL 140 group, PFS was 9 months (95% CI 2.2-15.8) and OS was 30 months (95% CI 9.5-50.4), while PFSwas 13 months (95% CI 10.5-15.5) and OS was 34 months (95% CI 6.9-61) in the MEL 200 group. There was no statisticallysignificant difference in PFS and OS between the two groups (p:0.6, p:0.7).Conclusion: Consequently, MEL 140 and MEL 200 were found similar in terms of engraftment duration, transplant-relatedmortality rate, and survival rates. The idea that similar outcomes in both MEL 140 and MEL 200 group in patients who receivedcombined induction treatment with novel agent suggested that MEL 140 may be used more commonly than the standardapproach of MEL 200.