title: Absolute values of immunoglobulin free light chains are prognostic in patients with primary systemic amyloidosis undergoing peripheral blood stem cell transplantation.
abstract: The immunoglobulin free light chain (FLC) is the precursor protein of amyloid in primary systemic amyloidosis (AL). Historically, the ability to monitor the amyloid protein precursor protein has been crude. We evaluated the utility of the FLC assay in a retrospective analysis of patients with AL undergoing peripheral blood stem cell transplantation (PBSCT). Ninety-three such patients had serial FLC measurements performed. The prognostic effects of the initial concentration and the extent of reduction of monoclonal FLC on survival were studied. There was a significantly higher risk of death in patients with higher baseline FLC (hazard ratio 2.6, P < .04). Baseline FLC correlated with serum cardiac troponin levels, and higher FLC levels were associated with more organs involved by amyloid, suggesting that high FLC levels may be associated with more advanced disease. The percent FLC reduction did not predict for survival, but the absolute level of FLC achieved after therapy did. Normalization of FLC level after PBSCT predicted for both organ response and complete hematologic response. Achievement of FLC response was a better predictor of survival than achievement of complete hematologic response or normalization of the FLC ratio. FLC measurements both before and after PBSCT are important predictors of patient outcome.
authors.affiliation: Division of Hematology and Internal Medicine, Mayo Clinic, Rochester, MN, USA. dispenzieri.angela@mayo.edu
authors.forename: Angela
authors.initials: A
authors.lastname: Dispenzieri
authors.forename: Martha Q
authors.initials: MQ
authors.lastname: Lacy
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Katzmann
authors.forename: S Vincent
authors.initials: SV
authors.lastname: Rajkumar
authors.forename: Roshini S
authors.initials: RS
authors.lastname: Abraham
authors.forename: Suzanne R
authors.initials: SR
authors.lastname: Hayman
authors.forename: Shaji K
authors.initials: SK
authors.lastname: Kumar
authors.forename: Raynell
authors.initials: R
authors.lastname: Clark
authors.forename: Robert A
authors.initials: RA
authors.lastname: Kyle
authors.forename: Mark R
authors.initials: MR
authors.lastname: Litzow
authors.forename: David J
authors.initials: DJ
authors.lastname: Inwards
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Ansell
authors.forename: Ivana M
authors.initials: IM
authors.lastname: Micallef
authors.forename: Luis F
authors.initials: LF
authors.lastname: Porrata
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Elliott
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Johnston
authors.forename: Philip R
authors.initials: PR
authors.lastname: Greipp
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Witzig
authors.forename: Steven R
authors.initials: SR
authors.lastname: Zeldenrust
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Russell
authors.forename: Dennis
authors.initials: D
authors.lastname: Gastineau
authors.forename: Morie A
authors.initials: MA
authors.lastname: Gertz
mesh_terms: D000328:Adult; D000368:Aged; D000682:Amyloid / Q000097:blood*; D000686:Amyloidosis / Q000097:blood* / Q000401:mortality / Q000628:therapy; D015415:Biomarkers / Q000097:blood; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000097:blood*; D008297:Male; D008875:Middle Aged; D036102:Peripheral Blood Stem Cell Transplantation; D011237:Predictive Value of Tests; D020127:Recovery of Function; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D000682:Amyloid; D015415:Biomarkers; D007147:Immunoglobulin Light Chains