Clinical use
To aid in the diagnosis and monitoring of Myeloma patients
Background
Myeloma is a cancer of a type of white blood cells called plasma cells. These cells come from the bone marrow and produce antibodies (or immunoglobulin) that are important in fighting infections. In myeloma, the abnormal plasma cells produce too much of one type of immunoglobulin called the M-protein. M-proteins crowd out all the other normal bone marrow cells, which eventually leads to the symptoms of myeloma.
The M-protein is made up of two types of molecules: heavy chain molecules and light chain molecules. The body produces more light chain molecules than it needs, so there are always free light chain molecules circulating in your blood. As abnormal myeloma cells produce more and more M-proteins, the level of free light chain molecules rises in the blood. There are two types of light chains: kappa and lambda chains. The ratio or proportion between the kappa and lambda light chains indicates an excess production of one chain over the other, and therefore can be used as an indication of disease progression or remission.
In contrast to older tests used to monitor myeloma, free light assays can identify even slight increases in light chain levels.
Reference ranges
Kappa Light Chains: 3.3 – 19.4 mg/L
Lambda Light Chains: 5.7 – 26.3 mg/L
Kappa:Lambda Ratio: 0.26 – 1.65
Patient preparation
None required
Specimen requirements
Serum – SST sample is required
Turnaround time
2 weeks