{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"Kappa detects surface immunoglobulin on normal and neoplastic B-cells. In paraffin-embedded tissue, Kappa exhibits strong staining of kappa-positive plasma cells and cells that have absorbed exogenous immunoglobulin.When studying B-cell neoplasms, the determination of light-chain ratios remains the centerpiece. Most B-cell lymphomas express either Kappa or Lambda light chains, whereas reactive proliferations display a mixture of Kappa and Lambda-positive cells. If only a single light-chain type is detected, a lympho-proliferative disorder is very likely. Monoclonality is determined by a Kappa-Lambda ratio greater than or equal to 3:1, a Lambda-Kappa ratio greater than or equal to 2:1, or a monoclonal population of 75% or more of the total population."}]}]}