Several types of non-myeloma exist.
The first of patients are non–producers, these abnormalities that may have defects in immunoglobulin synthesis.
These patients have all the features of a plasma cell disorder, but are not able to synthesize or secrete a protein.
These patients have no measurable blood protein in the blood or urine, may have significant plasma cell burden and evidence of organ damage, and even free like chain essays will be negative.
The next type of non-secretory myeloma reflect patients whose myeloma produces a protein but has defects in secretion.
Mutations in the immunoglobulin gene can account for lack of secretion in patients with a nonsecrettory myeloma.
These patients have defects in Ig secretion but are able to secrete some low levels of light chains, and have oligisecretory myeloma.
Some patients categorized as non–secretory myeloma , in fact have proteins that are not detected by SPEP or UPEP, but had free light chain only myeloma.
Light chain assay can detect Kappa and lambda light chains.