Second Autologous Stem Cell Transplant as Salvage in Multiple Myeloma - The Oregon Health and Science University Experience

Second autologous transplants (SAT) are commonly done to treat relapsed myeloma, though data on outcomes are lacking. We retrospectively studied all patients at OHSU in the past 20 years who received SAT for myeloma and report their outcomes. We found that SAT resulted in a median PFS of >1.5 years and median OS of >4.5 years with low rates of transplant-related mortality and modest toxicity. Background: : Second autologous transplants (SAT) are routinely performed in the setting of myeloma relapse, though data on outcomes are lacking. We conducted a single-center review of all multiple myeloma patients at OHSU who received SAT (excluding tandems) with responses assessed by International Myeloma Working Group (IMWG) criteria. Results: : Sixty-eight patients received SAT between 1999 and 2019. Risk by IMWG was available for 50 patients (10 high-risk). Median age at SAT was 61 (45-74). Median time between 1st and 2nd Autologous stem cell transplantation (ASCT) was 5.5 years (1.1 - 15.2). Median progression-free survival (PFS) after 1st ASCT (available for 53 pts) was 2.5 years (0.3 - 10). The average # of lines of therapy prior to SAT was 2.8 (1-14). SAT prep regimens (available for 67 pts) were: Fifty-one (87%) melphalan 200 mg/m2, 6 (9%) melphalan 140 mg/m(2), 1 (2%) BEAM, 1 (2%) melphalan 200 mg/m(2) and bortezomib. All used PBSC mobilization. Median overall survival (OS) after SAT was 4.68 years, and median PFS was 1.72 years. By treatment era (1999-2009 vs. 2010-2019), median OS was 1.97 vs. 5.52 years (P =.15). When analyzed by IMWG group (standard/low vs. high risk) median PFS and OS were not significantly different (1.87 vs. 1.61 years and 3.58 vs. 5.91 years, respectively). Treatment-Related Mortality (TRM) occurred in 1 patient (2%). Conclusion: : Our experience with SAT for multiple myeloma (MM) shows that it has low TRM and is effective, with median OS >4.5 years, though with a shorter PFS than after 1st ASCT. Published by Elsevier Inc.