意义未明的单克隆丙种球蛋白血症的临床特征及疾病进展相关因素分析

OBJECTIVE: To analyze the clinical presentation and progression risk factors of patients with monoclonal gammopathy of undetermined significance（MGUS）in China. METHODS: We retrospectively assessed the clinical features and disease progression of 1 037 patients with monoclonal gammopathy of undetermined significance between January 2004 and January 2022 at Peking Union Medical College Hospital. RESULTS: A total of 1 037 patients were recruited in the study, including 636 males（63.6％）, with a median age of 58（18–94）years. The median concentration of serum monoclonal protein was 2.7（0–29.4）g/L. The monoclonal immunoglobulin type was IgG in 380 patients（59.7％）, IgA in 143 patients（22.5％）, IgM in 103 patients（16.2％）, IgD in 4 patients（0.6％）, and light chain in 6 patients（0.9％）. 171 patients（31.9％）had an abnormal serum-free light chain ratio（sFLCr）. According to the Mayo Clinic model for risk of progression, the proportion of patients in the low-risk, medium-low-risk, medium-high risk, and high-risk groups were 254（59.5％）, 126（29.5％）, 43（10.1％）, and 4（0.9％）, respectively. With a median follow-up of 47（1–204）months, 34 of 795 patients（4.3％）had disease progression, and 22（2.8％）died. The overall progression rate was 1.06（0.99–1.13）/100 person-years. Patients with non-IgM MGUS have a markedly higher disease progression rate per 100 person-years than IgM-MGUS（2.87/100 person-years vs 0.99/100 person-years, P＝0.002）. The disease progression rate per 100 person-years in non-IgM-MGUS patients of Mayo classification low-risk, medium-low risk and medium-high risk groups were 0.32（0.25–0.39）/100 person-years, 1.82（1.55–2.09）/100 person-years, and 2.71（1.93–3.49）/100 person-years, which had statistically difference（P＝0.005）. CONCLUSION: In comparison to non-IgM-MGUS, IgM-MGUS has a greater risk of disease progression. The Mayo Clinic progression risk model applies to non-IgM-MGUS patients in China.