Autologous stem cell transplantation in primary systematic amyloidosis: The impact of selection criteria on outcome

Autologous stem cell transplantation (ASCT) for primary systemic amyloidosis (AL) produces high hematologic and organ responses. However, treatment-related mortality remains high and reported series are subject to selection bias. In all, 48 of 80 amyloid patients referred to our center had AL in the absence of myeloma, 26 of these 48 were deemed transplant candidates and 20 actually underwent ASCT. Transplant-related mortality has fallen from 50 to 20% since January 1999 due to better patient selection and prophylactic measures. Intent-to-treat organ responses were renal (46%), cardiac (25%) and liver (50%). Organ responses in patients who survived transplantation were renal (75%), cardiac (40%) and liver (100%). The 3-year OS post-ASCT was 56% with improved outcome predicted by a better performance status (P = 0.08), normal ALP (P = 0.08), nephrotic syndrome (P = 0.01) and the absence of severe hypotension (P = 0.01). The 3-year OS for all referred patients was 44% and this was not significantly better for transplant candidates. Patients with significant hypotension (systolic blood pressure ≤ 90 mmHg) or poor performance status (ECOG > 2) have an exceedingly high treatment-related mortality and should not be transplanted. For those undergoing ASCT, organ response rates appear promising, but conclusive evidence of improved survival for this select group of patients is still lacking and will require randomized trials.