Characteristics of long term survivors of multiple myeloma after autologous stem cell transplantation: a retrospective analysis from a tertiary care centre in India.

Abstract

Outcome of newly diagnosed, transplant eligible, multiple myeloma (MM) patients have improved significantly during the past two decades. A small proportion of patients are long term survivors beyond 10 years. We evaluated clinical and laboratory characteristics of these long term survivors. Four hundred and thirty eight consecutive MM patients underwent autologous stem cell transplantation (ASCT) between 1995 and 2019. Patients median age was 52 years, (range, 20-73) and 291 (66.4%) were males. 35.3% had ISS stage III disease. 96 (21.9%) patients were long term survivors (LTS), defined as those alive 120 months or more. Compared to others, LTS patients more frequently had ISS stage I (42% vs 28.5%, p < 0.001), serum albumin ≥3.5 g/dl (72% vs 57%, p < 0.005), platelet count ≥150,000/μL (88% vs 71%, p < 0.001), eGFR ≥40 ml/min (85.4% vs 75%, p < 0.01), and bone marrow plasma cells ≤40% (60% vs 49%, p < 0.03). Transplant within 12 months of diagnosis (73% vs 51.5%, p < 0.001) and in first remission (89.6% vs 71.3%, p < 0.001) were more common in LTS. Post-ASCT response was superior: CR (80% vs 65.5%, p < 0.004), CR + VGPR (94.8% vs 82.5%, p < 0.001). At median follow-up of 115 months, median overall survival was 264 months and progression-free survival 158 months. This study identifies a distinct subgroup of MM patients with long-term survival, characterized by favourable baseline features, early and effective treatment, and deep post-transplant responses, with a median progression-free survival exceeding 13 years. No funding was received for present study.