Immunoglobulin free light chain ratio is an independent risk factor for progression of smoldering (asymptomatic) multiple myeloma by Angela Dispenzieri, Robert A. Kyle, Jerry A. Katzmann, Terry M. Therneau, Dirk Larson, Joanne Benson, Raynell J. Clark, L. Joseph Melton, Morie A. Gertz, Shaji K. Kumar, Rafael Fonseca, Diane F. Jelinek, and S. Vincent Rajkumar Blood Volume 111(2):785-789 January 15, 2008 ©2008 by American Society of Hematology

Effect of increasingly abnormal FLC ratio on the relative risk of progression of SMM to MM or related disorder. Effect of increasingly abnormal FLC ratio on the relative risk of progression of SMM to MM or related disorder. As the serum kappa/lambda FLC ratio becomes increasingly abnormal, the risk of progression increases. The middle curve in represents relative risk; upper and lower curves represent 95% confidence intervals. Vertical bars represent the normal range for kappa to lambda ratio. (A) Unadjusted. (B) Adjusted for BMPC count and M protein. Angela Dispenzieri et al. Blood 2008;111:785-789 ©2008 by American Society of Hematology

Risk of progression to myeloma or related disorder in 273 patients with SMM. Risk of progression of SMM to active myeloma using serum κ to λ FLC ratio of less than 0.125 (< 1:8) or more than 8 (top curve) versus 0.125 to 8 (bottom curve). Risk of progression to myeloma or related disorder in 273 patients with SMM. Risk of progression of SMM to active myeloma using serum κ to λ FLC ratio of less than 0.125 (< 1:8) or more than 8 (top curve) versus 0.125 to 8 (bottom curve). Angela Dispenzieri et al. Blood 2008;111:785-789 ©2008 by American Society of Hematology

Risk stratification based on bone marrow plasmacytosis, serum M protein, and serum immunoglobulin FLC ratio. Risk stratification based on bone marrow plasmacytosis, serum M protein, and serum immunoglobulin FLC ratio. Patients are assigned 1 point for meeting each of the following criteria: BMPCs greater than or equal to 10%; serum M protein greater than or equal to 3 g/dL; and serum immunoglobulin FLC ratio either less than 0.125 or more than 8. The median times to progression for 1, 2, or 3 risk factors are 10, 5.1, and 1.9 years, respectively. Angela Dispenzieri et al. Blood 2008;111:785-789 ©2008 by American Society of Hematology