Objective: To explore the clinical and laboratory characteristics of mutiple myeloma patients with CD20 expression.
Methods: Review the data of mutiple myeloma patients and analyze the clinical and laboratory characteristics of CD20 positive patients, compared with CD20 negative patients.
Results: (1)Totally 465 cases of newly-diagnosed MM were collected with CD20 expression status detected by multi-color flow cytometry. Sixty two patients (13.3%) were CD20 positive and the others were negative. (2)No statistical differences were found between CD20 positive and negative groups about the sex ratio, age predominance, D-S staging, ISS staging, renal insufficiency rate, platelet count, LDH level and classifications by paraprotein(all P value>0.05). (3)Compared with those of CD20 negative patients, the hemoglobulin value(74.5 g/L vs 83.5 g/L, P=0.021), extramedullary involvement rate (3.5% vs 13.7%, P=0.029), CD56-positive rate(36.7% vs 68.8%,P=0.000), t(4;14)translocation rate(2.4% vs 24.0%, P=0.001) in CD20 positive patients were lower statistically. (4)Compared with those of CD20 negative patients, the percentage of plasma cells (0.400 vs 0.295, P=0.045) by marrow smear differential counting, the percentage of myeloma cells(20.0% vs 6.8%, P=0.000) by multi-color flow cytometry analysis, CD45-positive rate(12.1% vs 4.5%, P=0.018), CD79a-positive rate(9.8% vs 1.5%, P=0.013) and t(11;14) translocation rate(60.5% vs 14.4%, P=0.000)in CD20 positive patients were higher statistically. (5)There was no statistical differences about the overall response rate (ORR), complete response rate (CRR), TTP(time to progression), PFS(progression free survival) and overall survival (OS) between CD20 positive and negative groups.
Conclusion: CD20 positive rate is 13.3% in multiple myeloma pateints according to our data. CD20 poaitive myeloma were prone to residing in bone marrow and affecting erythropoiesis. Atypical immunophenotypes were more common, and the incidence of t(11;14) were increased markedly while that of t(4;14)were rare for CD20 positive multiple myeloma.
目的: 分析CD20阳性多发性骨髓瘤（MM）患者的临床和实验室检查特征。
方法: 回顾性分析62例CD20阳性初诊MM患者的临床及实验室检查资料，并与CD20阴性患者进行比较。
结果: ①采用流式细胞术进行CD20分析的465例初诊MM患者中，CD20阳性者62例（13.3%）。②CD20阳性与阴性组患者比较，其性别、年龄、Durie-Salmon分期、ISS分期、肾功能损害、LDH水平、血小板计数及免疫球蛋白类型差异均无统计学意义（P值均>0.05）。③CD20阳性组患者血红蛋白水平（74.5 g/L对83.5 g/L，P=0.021）、髓外浸润发生率（3.5%对13.7%，P=0.029）、CD56阳性细胞率（36.7%对68.8%，P=0.000）、t（4;14）发生率（2.4%对24.0%，P=0.001）明显低于CD20阴性组。④CD20阳性组患者骨髓浆细胞比例（0.400对0.295，P=0.045）及恶性浆细胞比例（20.0%对6.8%，P=0.000）、CD45阳性细胞率（12.1%对4.5%，P=0.018）、CD79a阳性细胞率（9.8%对1.5%，P=0.013）、t（11;14）发生率（60.5%对14.4%，P=0.000）明显高于CD20阴性组。⑤两组患者对治疗的反应率、完全缓解率、无进展生存及总体生存时间差异均无统计学意义（P值均>0.05）。
结论: MM患者CD20阳性发生率为13.3%，CD20阳性MM患者的瘤细胞更易在骨髓浸润，累及红系造血，免疫表型更多为不典型表现。与CD20阴性患者比较，CD20阳性患者t（11;14）发生率明显升高，而t（4;14）发生率明显降低。