继发性意义未明的单克隆免疫球蛋白血症35例研究

 目的　研究继发性意义未明的单克隆免疫球蛋白血症（sMGUS）在接受不同治疗的多发性骨髓瘤（MM）患者中的发生率，分析其对患者的治疗反应和长期生存的影响。方法　回顾性分析515例MM患者的临床资料及血清免疫固定电泳（IFE）结果，分析sMGUS患者的IFE图谱特征，对sMGUS组和非sMGUS组疗效分布组成进行比较，对2组进行生存曲线分析。结果　515例MM患者中含接受自体造血干细胞移植（auto-SCT）治疗的患者73例，单纯联合化疗患者442例，共发现35例sMGUS，总发生率为6.8 %；经auto-SCT治疗和单纯联合化疗治疗后sMGUS的发生率分别为19.2 %（14／73）和4.8 %（21／442），二者差异有统计学意义（χ2＝20.587，P＝0.002）；sMGUS组与非sMGUS组在初诊MM时的M蛋白类型分布差异无统计学意义（χ2＝6.396，P＝0.380）；sMGUS组与非sMGUS组完全缓解（CR）率分别为45.7 %（16／35）和14.3 %（59／480），差异有统计学意义（χ2＝22.961，P＜0.001），2组疗效分布组成经秩和检验分析，差异有统计学意义（P＜0.001）；经Kaplan-Meier法生存曲线分析，sMGUS组的中位生存时间为42个月（5～112个月），非sMGUS组的中位生存时间为14个月（1～120个月），二者差异有统计学意义（P＜0.001），对auto-SCT治疗患者单独分析，经auto-SCT治疗后出现sMGUS的患者，中位生存时间为30.8个月（5～111个月），未出现sMGUS的患者中位生存时间为39.3个月（2～120个月），二者差异有统计学意义（P＝0.002）。结论　sMGUS的发生可能与免疫重建或经大剂量免疫抑制治疗后的免疫失调有关，MM经auto-SCT治疗后出现sMGUS的概率大于经单纯联合化疗治疗者，同非sMGUS患者相比，sMGUS患者有着更好的疗效和预后，但对于auto-SCT治疗患者，发生sMGUS并非是一个良好的预后因素。

Study on 35 cases of secondary monoclonal gammopathy of undetermined significance

Objective　To study the frequency and characteristics of secondary monoclonal gammopathy of undetermined significance(sMGUS) in multiple myeloma (MM), and analyze the impact on survival. Methods　The data of 515 patients with MM admitted were analyzed retrospectively. 73 cases of patients underwent stem cell transplantation and 442 patients received thalidomide or bortezomib based chemotherapy. Immunofixation electrophoresis(IFE) and clinical characteristics were respectively analyzed, and the comparison of survival between sMGUS group and non-sMGUS group was performed. Results　Thirty-five cases (6.8 %) of myeloma patients with sMGUS were found in all patients. The incidence of sMGUS after hematopoietic stem cell transplantation treatment is significantly higher than that of receiving chemotherapy (19.2 % versus 4.8 %, χ2 = 20.587, P = 0.002). The CR rates of sMGUS group and non-sMGUS group were 45.7 % (16/35) and 14.3 % (59/480) (χ2 = 22.961, P < 0.001). The median survival time of patients with sMGUS was much prolonged compared with the control cohort (42.0 versus 14.0 months, P < 0.001). However, when the analysis was restricted on patients underwent stem cell transplant, patients with sMGUS had a negative impact on outcome ,and the median overall survival was 30.8 and 39.3 months (P = 0.002). Conclusion　The sMGUS may be attributed to either immune reconstitution or immune system dysregulation after highly immunosuppressive therapy. The incidenceof sMGUS after auto-SCT treatment is higher than chemotherapy. The sMGUS group has the higher response rate and longer survival. But for auto-SCT treatment patients, sMGUS may be not a good prognostic factor.