Study on 35 cases of secondary monoclonal gammopathy of undetermined significance / 白血病·淋巴瘤

ABSTRACT

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 ％,x2 =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) (x2 =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.