A Large-Scale Analysis of Autologous Stem Cell Transplantation for Multiple Myeloma Patients Older than 65 Years

The role of autologous hematopoietic stem cell transplantation (auto-HCT) in multiple myeloma (MM) patients over 65 years remains unclear due to their underrepresentation in clinical trials. This study evaluates the safety and efficacy of auto-HCT in this population using real-world data from the TriNetX network.

A retrospective cohort study was conducted on MM patients treated at Hospital 12 de Octubre (2013-2023). Three cohorts were analyzed: patients > 65 years undergoing auto-HCT (n = 60), ≤ 65 years with auto-HCT (n = 235), and > 65 years without auto-HCT (n = 59). A validation cohort from TriNetX included 5087 patients > 65 and 10,667 ≤ 65 years receiving auto-HCT, along with 54,757 > 65 years without auto-HCT. Primary outcomes included progression-free survival (PFS), time to next treatment (TNT), overall survival (OS), and non-relapse mortality (NRM).

Auto-HCT improved PFS and OS in selected elderly patients. The 6-year PFS was 45.0% (> 65) versus 55.0% (≤ 65) (HR 1.25; P = .365), and the 6-year OS was 57.8% (> 65) versus 81.1% (≤ 65) (HR 2.11; P = .025). TNT rates were similar (64.4% vs. 63.6%; HR 0.93; P < .01). Toxicity and mortality were comparable. These findings support auto-HCT as a valuable consolidation therapy in selected elderly MM patients, emphasizing the need for personalized strategies to optimize outcomes.