Autologous stem-cell transplantation in progressing amyloidosis is associated with severe transplant-related toxicity

BACKGROUND: Amyloid light-chain (AL) amyloidosis is a disorder of plasma cells in which depositions of immunoglobulin light-chain fragments cause progressive organ failure and death with a median survival of one year, but autologous stem-cell transplantation can induce high response rates, especially in isolated renal involvement. METHODS: Six patients aged between 43 and 59 years were diagnosed with AL-amyloidosis and had stem cells mobilized with either recombinant human granulocyte colony-stimulating factor (rhG-CSF) alone (n = 2) or cyclophosphamide (2-4 g/m(2)) and rhG-CSF (n = 4). All six patients had kidney involvement and nephrotic syndrome, four had cardiac involvement and two involvement of the vascular, nervous and gastrointestinal systems. Five of the patients received high-dose melphalan (200 mg/m(2)) and autologous blood stem-cell support. RESULTS: One patient died as a result of sepsis after stem-cell mobilization. The other five patients received high-dose melphalan but experienced severe toxicity. One patient died as the result of gastrointestinal perforation on day 6, one presented with hyperfibrinolysis and spontaneous rupture of the spleen, and another experienced severe bleeding of the gastrointestine, tachyarrhythmia and hemolytic anemia. Four patients had acute renal failure: three required hemodialysis and one underwent renal transplant 21 months later. Restaging after a follow-up of 31-52 months revealed reversal of nephrotic syndrome in all three patients who regained adequate renal function. With respect to cardiac involvement (n = 2), one patient showed a decrease in NYHA class from II to I but baseline wall thickness remained stable. CONCLUSION: Treatment of selected patients with AL-amyloidosis by high-dose melphalan and stem-cell support results in reversal of amyloid-related disease in a substantial proportion of patients and improved survival.