Abnormal Heavy/Light Chain Ratio and Matched Pair Suppression Increase Residual Disease Detection Sensitivity in Patients With Multiple Myeloma With Deep Responses

Clin Lymphoma Myeloma Leuk. 2018 Apr;18(4):293-296. doi: 10.1016/j.clml.2018.01.008. Epub 2018 Feb 19.

Abstract

Background: Heavy/light chain (HLC) assay can quantify involved as well as uninvolved immunoglobulin pairs and is used to detect monoclonal proteins.

Patients and methods: We compared the sensitivity between HLC assay and serum protein electrophoresis, serum immunofixation electrophoresis (IFE), and free light chain (FLC) assay in patients with symptomatic multiple myeloma (n = 111) whose responses were stable disease or better.

Results: Among patients with negative IFE and normal FLC ratios, 84.4% (38 of 45) and 80% (36 of 45) exhibited normal HLC ratios and no pair suppression, respectively (13.3% [6 of 45], moderate pair suppression and 6.7% [3 of 45], severe pair suppression). The lower the monoclonal protein levels, the more the possibility that the patients had normal HLC ratios and no matched pair suppression (both P < .000001). HLC ratios or pair suppression combined with IFE results and FLC ratios were more sensitive for detecting monoclonal proteins than were IFE results and FLC ratios alone (P = .016 and .0039, respectively). A combination of all 4 methods (IFE, FLC, HLC, and pair suppression) was far more sensitive than were IFE findings plus FLC ratios alone (P = .00024).

Conclusion: Abnormal HLC ratios and HLC-matched pair suppression can increase the sensitivity for detecting residual disease in patients with multiple myeloma with deep responses.

Keywords: Free light chain; Hevylite; Immunofixation; Minimal residual disease; Pair suppression.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Monoclonal / blood
  • Blood Protein Electrophoresis / methods
  • Female
  • Humans
  • Immunoglobulin Heavy Chains / blood*
  • Immunoglobulin Light Chains / blood*
  • Male
  • Middle Aged
  • Multiple Myeloma / blood*
  • Multiple Myeloma / diagnosis*
  • Myeloma Proteins / analysis*
  • Neoplasm, Residual
  • Prospective Studies
  • Sensitivity and Specificity

Substances

  • Antibodies, Monoclonal
  • Immunoglobulin Heavy Chains
  • Immunoglobulin Light Chains
  • Myeloma Proteins
  • multiple myeloma M-proteins