title: Immunoglobulin light chain amyloidosis: 2014 update on diagnosis, prognosis, and treatment.
abstract: BACKGROUND
  Immunoglobulin light chain amyloidosis is a clonal, nonproliferative plasma cell disorder in which fragments of immunoglobulin light chain are deposited in tissues. Clinical features depend on organs involved but can include restrictive cardiomyopathy, nephrotic syndrome, hepatic failure, peripheral/autonomic neuropathy, and atypical multiple myeloma.
  
  
  METHODS
  Tissue biopsy stained with Congo red demonstrating amyloid deposits with apple-green birefringence is required for diagnosis. Invasive organ biopsy is not required because amyloid deposits can be found in bone marrow biopsy or subcutaneous fat aspirate in 85% of patients. Verification that amyloid is composed of immunoglobulin light chains is mandatory.
  
  
  CONCLUSIONS
  N-terminal pro-brain natriuretic peptide (NT-proBNP), serum troponin T, and difference between involved and uninvolved immunoglobulin free light chain values are used to classify patients into four groups of similar size; median survivals are 94.1, 40.3, 14.0, and 5.8 months.
  
  
  METHODS
  All patients with a systemic amyloid syndrome require therapy to prevent deposition of amyloid in other organs and prevent progressive organ failure of involved sites. Stem cell transplant (SCT) is preferred, but only 20% of patients are eligible. Requirements for safe SCT include NT-proBNP <5,000 ng/mL, troponin T <0.06 ng/mL, age <70 years, <3 organs involved, and serum creatinine ≤1.7 mg/dL. Nontransplant candidates can be offered melphalan-dexamethasone or cyclophosphamide-bortezomib-dexamethasone. Other combinations of chemotherapy with agents such as cyclophosphamide-thalidomide (or lenalidomide)-dexamethasone, bortezomib-dexamethasone, and melphalan-prednisone-lenalidomide have documented activity. Future Challenges: Late diagnosis remains a major obstacle to initiating effective therapy. Recognizing the presenting syndromes is necessary for improving survival.
authors.affiliation: Division of Hematology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Morie A
authors.initials: MA
authors.lastname: Gertz
mesh_terms: D000367:Age Factors; D000686:Amyloidosis / Q000097:blood / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D001853:Bone Marrow / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D001897:Boronic Acids / Q000627:therapeutic use; D000069286:Bortezomib; D003404:Creatinine / Q000097:blood; D003520:Cyclophosphamide / Q000627:therapeutic use; D003907:Dexamethasone / Q000627:therapeutic use; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000097:blood*; D008558:Melphalan / Q000627:therapeutic use; D011719:Pyrazines / Q000627:therapeutic use; D033581:Stem Cell Transplantation; D050151:Subcutaneous Fat; D016019:Survival Analysis; D020107:Troponin T / Q000097:blood
chemical_list: D000970:Antineoplastic Agents; D015415:Biomarkers; D001897:Boronic Acids; D007147:Immunoglobulin Light Chains; D011719:Pyrazines; D020107:Troponin T; D000069286:Bortezomib; D003907:Dexamethasone; D003520:Cyclophosphamide; D003404:Creatinine; D008558:Melphalan