Objective: To evaluate the prognostic value of serum free light chain ratio (rFLC) and difference (dFLC) in patients with multiple myeloma (MM) . Methods: Clinical data of 479 cases of newly diagnosed MM patients with FLC test records referred to our hospital from January 2012 to March 2016 were collected. rFLC preferred cut-off values were selected as≤14.828,14.828-364.597, ≥364.597 according to the literatures. The dFLC was divided into ≤112.85,112.85-2891.83, ≥2891.83 mg/L three groups. The rFLC and dFLC values among the death, the non-death, the progress and the non-progress groups were compared by t test. The correlation analysis showed that the rFLC and dFLC values were related to the death or progression of the disease. Logistic regression was used to analyze the correlation between each factor and death or progression. Univariate survival analysis (PFS) and total survival (OS) were performed using Kaplan-Meier. Single-variable and multivariate prognostic analysis were performed using Cox model. Results: The cutoff values of rFLC less than 14.828 or dFLC less than or equal to 112.85 mg/L impacted most significant on OS and PFS of the patients (P<0.05) . Different rFLC cut-off values between two groups showed that when rFLC=14.828, OS was significantly better than the other two groups (NR vs 61 & 47 months, P=0.019) ; different dFLC cut-off values between two groups disclosed that PFS and OS were statistically significant when dFLC less than or equal to 112.85 mg/L compared with the other two groups (P<0.05) . The 4-year PFS/OS rates in the initial dFLC≤112.85 mg/L and rFLC≤14.828 groups was significantly higher than of the other two groups. Conclusion: Different cutoff levels of rFLC and dFLC might have obviously effects on the prognoses of patients with newly diagnosed MM. The difference of survival prognosis would be more pronounced when rFLC≤14.828 or dFLC≤112.85 mg/L with lower risk of death and lower risk ratio, which might be ideal cutoff value for determining the prognosis of these patients.
目的： 比较评估初诊时血清游离轻链比值（rFLC）及差值（dFLC）对多发性骨髓瘤（MM）患者预后的价值。 方法： 收集整理2012年1月至2016年3月有FLC检测记录的479例初治MM患者的相关临床资料，采用四分位间距法将rFLC、dFLC进行分组。将rFLC分别为3组：≤14.828、14.828~364.597、≥364.597。将dFLC分为3组：≤112.85 mg/L、112.85~2 891.83 mg/L、≥2 891.83 mg/L。随后分别对不同分组进行预后分析比较。使用Kaplan-Meier进行无进展生存（PFS）和总生存期（OS）比较，使用Cox回归进行单因素、多因素预后相关性分析。 结果： 不同截断范围rFLC或dFLC患者的OS及PFS差异均有统计学意义。rFLC≤14.828组OS明显优于其他两组（未达到对61个月对47个月，P=0.019）；PFS与rFLC 14.828~364.597组相比，差异无统计学意义（P=0.227），与rFLC≥364.597相比，差异有统计学意义（P=0.024）。dFLC≤112.85 mg/L组与其他两组相比PFS、OS差异均有统计学意义。单因素、多因素分析显示rFLC仅与患者OS显著相关，而dFLC与患者OS、PFS均显著相关。4年OS率比较，rFLC≤14.828组4年OS率达90.84%，明显高于其他两组（59.29%、62.26%）；dFLC≤112.85 mg/L组4年OS率达89.97%，明显高于其他两组（41.32%、71.95%）（P<0.05）。 结论： 对于初治MM患者，不同截断范围的rFLC、dFLC对患者生存预后影响不同。其中rFLC≤14.828或dFLC≤112.85 mg/L，其生存预后差异更为明显，且具有更低的死亡风险，危险比也更低。以此截断值判断患者预后较为理想。.
Keywords: Multiple myeloma; Prognostic; Serum free light chain.