[Effect of Serum Free Light Chain on Renal Function and Prognosis in Patients with Newly Diagnosed Multiple Myeloma].
PMID: 31839051 DOI: 10.19746/j.cnki.issn.1009-2137.2019.06.025.
OBJECTIVE: To analyze the effect of serum free light chain (sFLC) on renal function and prognosis in patients with newly diagnosed multiple myeloma (MM).
METHODS: The clinical data of 70 newly diagnosed MM patients who received sFLC examination in Fujian Medical University Union Hospital were retrospectively analyzed from April 2012 to November 2016. Univariate analysis was used to analyze the risk factors that associated with renal impairment (RI) and prognosis. Logistic regression and Kaplan-Meier analyze were used to analyze the roles of sFLC in RI and the prognosis.
RESULTS: Out of the 70 patients, 20 patients had RI at the initial diagnosis. Compared to normal renal function group, RI group had lower level of hemoglobin, elevated levels of serum uric acid, corrected calcium, serum creatinine, serum β2 microglobulin, and involved sFLC, higher proportion of patients with ISS stage III, involved sFLC≥500 mg/L, hemodialysis (all P＜0.05). Multivariate logistic regression analysis showed that serum uric acid≥430 μmol/L, ISS stage III and a involved sFLC≥500 mg/L were all the independent risk factors for RI in patients with newly diagnosed MM patients (all P＜0.05). Receiver operating characteristic (ROC) curves analysis showed that the involved sFLC was 705.0 mg/L, which was a best cut-off value area under curve (AUC) for prediting RI in patients with MM was 0.727 (P=0.003), sensitivity was 65.0% and specificity was 82.0%). After a median follow-up period of 31 (1-84) months, the median overall survival (OS) of patients with involved sFLC≥500mg/L and involved sFLC＜500 mg/L were 52.0 and 27.0 months, respectively, there was no statistically significant difference (P=0.137). There was also no statistically significant difference in median OS between the high sFLC ratio group (κ/λ＞32 or ＜0.03) and the low sFLC ratio group (0.03≤κ/λ≤32) (27 months vs 40 months, P=0.436).
CONCLUSION: The involved sFLC in the RI group is significantly higher than that in the normal renal function group in newly diagnosed MM patients. Serum uric acid≥430 μmol/L, ISS stage III and involved sFLC≥500 mg/L are the independent risk factors for RI. Monitoring sFLC in newly diagnosed MM patients is helpful to the prediction of RI, and the involved sFLC level or sFLC ratio may not affect the prognosis of newly diagnosed MM patients.
方法: 选取并回顾性分析2012 年4 月至2016 年11 月我院收治的70 例初诊MM且有行sFLC检查的患者的临床资料，将可能的肾功能损害相关危险因素及影响预后的因素进行单因素分析，通过Logistic回归分析及Kaplan-Meier生存分析等方法分析sFLC在初诊MM患者肾损害和预后中的作用.
结果: 70 例患者中有20例发生肾功能损害，相比于肾功能正常组，肾功能损害组的血红蛋白（Hb）水平低，血尿酸（Uric acid）、校正血钙（Corrected calcium）、血肌酐（Scr）、血清 β2微球蛋白（S-β2-MG）、受累sFLC（Involved sFLC）水平均高；ISS III期、受累sFLC≥500 mg/L、行血液透析的比例均明显升高（P＜0.05）。多因素Logistic回归分析提示：血尿酸≥430 μmol/L、ISS III期和受累sFLC≥500 mg/L均是初诊MM患者发生肾功能损害的独立危险因素（P＜0.05）；进一步用ROC曲线分析提示受累sFLC为705.0 mg/L，这是预测初诊MM患者发生肾损害的最佳阈值（AUC为0.727，P=0.003，敏感性为65.0%，特异性为82.0%）。患者中位随访31.0（1-84）个月，受累sFLC≥500 mg/L组和受累sFLC＜500 mg/L组的中位生存期分别为27.0和52.0个月，差异无统计学意义（P=0.137）；sFLC高比率组（κ/λ＞32或＜0.03）和低比率组（0.03≤κ/λ≤32）的中位生存期同样无显著的统计学差异（27 vs 40个月，P=0.436）.
结论: 初诊MM患者肾功能损害组的受累sFLC水平高于肾功能正常组，血尿酸≥430 μmol/L、ISS III期和受累sFLC≥500 mg/L是初诊MM患者发生肾功能损害的独立危险因素。监测sFLC有助于肾功能损害的预测，受累sFLC的水平或sFLC比率不影响患者的预后.