Investigation of the Diagnostic Value of sFLC and Other Indicators in the Detection of M Protein in LCMM.

ABSTRACT

BACKGROUND: The aim was to explore the diagnostic value of serum free light chain (sFLC) and other laboratory indicators for the patients with light chain multiple myeloma (LCMM). METHODS: We performed a retrospective study including 82 LCMM cases and 43 healthy subjects as the observation and control groups, respectively. The observation group was further divided into two subgroups κ- and λ-type LCMM. Sixteen quantitative indicators were collected and the difference among groups was compared. We also evaluated the positive detection rate (PDR) of four qualitative indicators for M protein detection. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of sixteen indicators. RESULTS: Fourteen indicators showed statistical differences between the control group and κ- or λ-type LCMM subgroup. The κ and λ sFLC ratio (rFLC) and the difference between κ and λ FLC (dFLC) showed differences among the three groups. Among the four qualitative indicators of M protein detection, rFLC showed the highest PDR for both κ- and λ-type LCMM. Among the three combinations with rFLC or uIFE did not show statistical differences. ROC curve analysis indicated a relatively high diagnostic value of dFLC for both κ- and λ-type LCMM. CONCLUSIONS: We should be vigilant about the missed diagnosis by observing the changes of MM-related indicators, particularly dFLC and the six other indicators with high diagnostic value. rFLC can improve the diagnostic ability of LCMM.