High-dose melphalan-based autotransplants for multiple myeloma: The Arkansas experience since 1989 in 3077 patients

BACKGROUND. In this report, the authors describe their collective experience with melphalan-based autotransplants since the inception of their program at the University of Arkansas for Medical Sciences in 1989. METHODS. The authors evaluated the clinical outcomes of 3077 successive patients with multiple myeloma (MM) who underwent at least 1 melphalan-based autotransplantation at the University of Arkansas. Of these, 1078 patients were enrolled on front-line Total Therapy (TT) protocols (TT-P) TT1, TT2, and TT3; 1104 patients were entered on protocols for newly diagnosed or previously treated patients (non-TT-P); and 895 patients were treated off protocol (non-P). RESULTS. The 10-year overall survival (OS) rates after first transplantation were 41%, 19%, and 11% (P < .001) for the TT-P, non-TT-P, and non-P groups, respectively. In the TT-P group, the median OS was 72 months on TT1, was not reached at ≥7 years on TT2, and was 88% at 2 years on TT3. Among 2683 patients with complete baseline data, absence of hypodiploidy/chromosome 13 deletion, β-₂-microglobulin <3.0 mg/L, C-reactive protein <6 mg/L, albumin >3.0 g/dL, and platelet count ≥100,000/μL all were associated independently with superior OS (P < .001), event-free survival (P < .001), and duration of complete remission (P < .001). CONCLUSIONS. The results from this large, single-institution experience demonstrated that > 10-year OS was accomplished in >40% of all patients enrolled on TT-P, whereas such success was obseived in only 15% of the remaining patients (including 25% in the presence of all 5 good-risk features). Superior outcomes with protocol-based, primary transplant regimens such as TT-P draw attention to the importance of applying the best available therapies upfront.