Clinical outcomes of ASCT in multiple myeloma: a study of the Plasma Cell Dyscrasia Working Party of PBMT

Autologous stem cell transplantation (ASCT) consolidation is the standard of care treatment for newly diagnosed and relapsed refractory multiple myeloma (MM) patients who are transplant eligible. However, data on outcomes in low- and middle-income countries (LMICs) are scarce. This is a multicenter retrospective study including 269 consecutive patients of MM who underwent ASCT between January 2005 and December 2023 across 6 different centers of Pakistan. Median age was 49 (21-72) years with male to female ratio 2.5:1. Commonest presenting symptom was backache in 157(58%), monoclonal paraprotein bands were detected in 234 (87%) patients, the most common subtype being IgG kappa 73(37%). Bortezomib, lenalidomide, dexamethasone (VRd) was the most used induction regimen in 112 (41.8%) patients. Conditioning regimens included melphalan 200 mg/m 2 in 137(51%) of the patients, melphalan 140 mg/m 2 in 118 (44%), and 100-160 mg/m2 in 14 (6%) patients. Post-transplant consolidation therapy was administered to 22 (8.5%) patients, while maintenance therapy (lenalidomide/ proteasome inhibitor + lenalidomide) was given to 229 (85%). The median overall survival (OS) was 72.5 months (95% CI, 55.0–90.0), while median progression free survival (PFS) was 46.0 months (95% CI, 35.8–56.2). Multivariate analysis documented superior OS and PFS for patients transplanted in CR or better and use of Melphalan 200 mg/m2 versus 140 mg/m2 conditioning. ASCT remains a viable and effective treatment option for MM patients in resource-constrained settings. Efforts should focus on improving diagnostics, optimizing induction regimens, and expanding post-transplant maintenance to maximize survival outcomes in LMICs.