Free Kappa / Lambda Light Chains

What it isLight chains are the small subunits of antibodies. A small amount of free, unbound light chains circulates normally; cancers of plasma cells produce one type in vast excess.

DoesScreens for and monitors plasma cell disorders — multiple myeloma, MGUS, AL amyloidosis.

GoodBalanced kappa and lambda with a normal ratio rules out monoclonal plasma cell disease.

BadSkewed ratio with elevation of one light chain type strongly suggests plasma cell dyscrasia. Persistent imbalance prompts hematology evaluation.