A Single Institution Retrospective Analysis of Outcomes in Multiple Myeloma Patients Aged 50 and Younger Undergoing Autologous HCT

Abstract

Introduction and Objectives Multiple myeloma (MM) is a disease of the elderly with the median age of diagnosis being 66 years and rare in the population younger than 50 years. Younger patients generally undergo autologous HCT as part of their treatment once they achieve an adequate response. Overall survival in patients with MM has dramatically improved over the last 2 decades with the advent of novel agents. The purpose of this retrospective analysis was to evaluate the disease behavior and transplant outcomes in patients younger than 50 years. Methods We retrospectively reviewed the charts of 29 patients aged ≤50 who underwent autologous HCT between May 2003 and Dec 2017 at our institution. All patients received Melphalan as their conditioning regimen. 28% (n=8) of the patients had renal insufficiency at the time of diagnosis (serum Creatinine ≥ 2.0 mg/dl). Results 38 auto-HCTs were performed in this group of patients. 7 patients underwent salvage transplant and 2 patients underwent planned tandem auto-HCT. Nearly 80% (n=23) patients had Salmon Durie stage 3 disease at the time of auto-HCT. Overall survival for the entire cohort was 109 months and PFS was 51 months. Median age at diagnosis was 46 years. The median age of the first transplant is 47 years. Median time to relapse/progression was 31 months after auto-HCT for the entire cohort. For patients with high-risk cytogenetics (28%, n=8) median time to relapse was 13 months compared to 72 months in standard risk patients. There was total of 12 deaths in the entire cohort with the majority of deaths (10/12) due to disease progression/relapse and 1 died from a secondary malignancy. Median time to relapse/progression after salvage HCT was 16 months. Of the 7 patients who underwent salvage HCT, 3 died secondary to disease progression with a median time to death is 12.6 months. Conclusion Despite recent advances in the treatment of multiple myeloma, younger patients with high-risk disease status continue to have poor outcomes. Aggressive induction regimens and possible planned tandem Auto-PBSCT may be a reasonable approach to improve outcomes in younger patients with high-risk disease status. Further studies with a larger cohort are warranted to corroborate our findings and also find ways to improve survival in this high-risk group.