Serum test for assessment of patients with Bence Jones myeloma

Definition of organ involvement and treatment response in immunoglobulin light chain amyloidosis (AL): A consensus opinion from the 10th International Symposium on Amyloid and Amyloidosis

“…Third, the percentage of plasma cells in the bone marrow of AL patients averages approximately 5%, and because these are frequently visual estimates, an accurate confirmation of a reduction that is not attributable to sampling or variability between hematopathologists is difficult. The use of the serum free light chain assay has been important for quantification of hematologic responses [94] and has been proposed as a useful tool to define hematologic response [95]. At this time, insufficient data exist to replace urine M protein measures in the response criteria.…”

International Myeloma Working Group guidelines for serum-free light chain analysis in multiple myeloma and related disorders

“…2 Approximately 10-30 g of FLC can be metabolized per day by the kidneys compared with normal plasma cell production of 0.5-1 g per day. 3 Abnormal concentrations of k and l FLC may result from a number of clinical situations including immune suppression, immune stimulation, reduced renal clearance, or monoclonal plasma cell proliferative disorders. Sera from patients with either polyclonal hypergammaglobulinemia or renal impairment often have elevated k FLC and l FLC due to increased synthesis or reduced renal clearance.…”

Determining the undetermined

“…3 They found that the incidence of progression to more aggressive disease, especially AML, and survival were similar in the 2 patient populations (Figure 3 of Jädersten et al). Although the comparison did not result from a randomized study, these findings are reassuring.…”

“…1,2 The Stanford and Nordic MDS groups showed that low pretreatment serum EPO levels (Ͻ 500 U/L) and relatively low transfusion requirement (Յ 2 RBC units/ month) were favorable prognostic factors of response to EPO ϩ G-CSF, whereas patients classified in the low or intermediate-1 groups according to the MDS International prognostic scoring system (IPSS; based on percentage of marrow blasts, number of cytopenias, and karyotype) also had better response. [1][2][3] However, most published studies with EPO in MDS had short follow-up and the longterm effect of EPO ϩ G-CSF on anemia, natural disease history, and survival remained uncertain. In particular, the risk that those growth factors (especially G-CSF) could trigger progression to AML remained of concern.…”