Fifteen year overall survival rates after autologous stem cell transplantation for AL amyloidosis

In appropriately selected patients with AL amyloidosis, autologous stem cell transplant (ASCT) is an established treatment modality with excellent outcomes and decreasing transplant related mortality (TRM) over time. We report on 15-year overall survival (OS) in 159 patients undergoing ASCT from 1996 to 2003, with median follow up of 17.1 years. Day 100 TRM was 13.2% (n = 21). The OS of ≥15 years was observed in 30% (47/159) of patients. Patients surviving ≥15 years were younger (53 vs 56 years, P =.02), less likely to have lambda as the involved light chain (62% vs 78%, P =.03) and were less likely to have heart involvement (32% vs 56%, P =.005). Median OS of patients with heart involvement vs not was 4.0 vs 11.1 years, P =.006 and actuarial 15-year OS was 23% vs 43%, respectively. A higher proportion of patients with OS ≥15 years received full-dose melphalan conditioning (81% vs 61%, P =.01), and achieved day 100 complete response (CR) (64% vs 24%, P <.001). Median OS amongst patients who achieved CR vs not was 19.3 vs 5.4 years, P <.001. Heart involvement, receiving full-dose melphalan and achieving CR remained independent predictors of OS. AL amyloidosis and related complications were the cause of death in 52% of patients overall (1-5 years post-transplant: 81%; 5-10 years: 62% and 10-15 years: 55%). These results reinforce the key role of ASCT in AL amyloidosis. With improvements in TRM and more options for relapsed disease, we expect the long-term survival post-transplant to improve significantly in the future.