Light chain type predicts organ involvement and survival in AL amyloidosis patients receiving stem cell transplantation

We evaluated the impact of light chain type, lambda (λ) or kappa (κ), on disease features and outcomes in patients with immunoglobulin light chain (AL) amyloidosis receiving stem cell transplant at the Mayo Clinic between October 2002 and August 2016. Patients with λ AL amyloidosis had higher rates of renal and neurological involvement (λ 69% vs κ 57%, P = .02 and λ 16% vs κ 9%, P = .03, respectively). Patients with κ AL amyloidosis had more hepatic involvement (λ 7% vs κ 18%, P = .0003). Complete response rate was 43% for both groups and overall response rates were similar (λ 85% vs κ 91%, P = .12). Patients with κ light chain amyloidosis had better progression-free and overall survival (PFS: λ 74 months vs κ 101 months, P = .0064 and OS: λ 121 months vs κ not reached, P = .003). Mayo stage 2004 was more predictive of survival in the λ cohort (median OS of 143 months stage I vs 77 months stage II vs 33 months stage III, P < .0001) than in the κ cohort (median OS not reached for stage I and II and 102 months for stage III, P = .044). Conditioning dose predicted survival in the λ cohort only (median OS 149 months for melphalan 200 mg/m² vs 50 months for melphalan <200 mg/m², P < .0001; median OS κ not reached for melphalan 200 mg/m² or <200 mg/m², P = .38). On multivariate analysis, light chain type remained an independent predictor of survival. Light chain type predicts organ involvement and survival in patients with AL amyloidosis receiving stem cell transplant.