Objective: To retrospectively analyze the laborotary test results and clinical data of 31 patients with mixed phenotype acute leukemia (MPAL) in order to summarize and discuss the biological characteristics, curative effect, and prognosis of each subtype of MPAL based on immunophenotype results.
Methods: MPAL patients diagnosed and treated in our hospital from July 2013 to January 2019 were selected to analyze the data of cell morphology, immunophenotyping, cytogenetics, molecular biology (MICM), and routine blood at initial diagnosis. Follow-up was carried out until the last discharge time.
Results: Among 31 patients, there were 19 males and 12 females, with a median age of 41(12-76) years old. According to the results of immunophenotyping and EGIL score, there were 16 cases of myeloid-T lymphoid mixed phenotype (myeloid-T group), 9 cases of myeloid-B lymphoid mixed phenotype (myeloid-B group), 5 cases of T-B lymphoid mixed phenotype (T-B group), and 1 case of myeloid-T-B lymphoid mixed phenotype. Compared between different subtypes, the antigen expression characteristics were the highest positive rate and expression rate of HLA-DR in myeloid-B group, and the positive rate of CD2 in T-B group was significantly higher than that in the myeloid-T group. Meanwhile, the expression rates of CD7 and cCD3 (cytoplasmic CD3) in T-B group were higher than those in myeloid-T group, and cCD79a was positive in all cases of myeloid-B group and T-B group. The median WBC of T-B group was 81.92×109/L, which was significantly higher than that of the other two groups (P<0.05). The quantitative results of WT1 were higher than 10-4 in 92.6% of the patients, and the WT1 expression level in myeloid-B group was significantly lower than the other two groups (P<0.01). Among the 9 patients with myeloid-B mixed phenotype, 5 cases showed BCR-ABL positive. Among 28 patients followed up, 21 cases achieved complete remission (CR), the median time to first obtain CR was 32.5(9-75) days, and the median follow-up time was 16 months (range from 21 days to 6 years). The CR rate and median overall survival (OS) time in myeloid-B group were 88.9% and 40 months, which were higher than the other two groups. The CR rate and 3-year OS rate in T-B group were relatively lower (50.0%, 0).
Conclusion: WT1 gene is highly expressed in patients with MPAL, and each subgroup of MPAL based on immuophenotype has its unique antigen expression characteristics. Compared with myeloid-T group and T-B group, myeloid-B group can acquire higher remission rate and have better prognosis.
题目: 混合表型急性白血病患者免疫表型特点及临床预后特征分析.
目的: 回顾性分析31例混合表型急性白血病（MPAL）患者的实验室结果和临床资料，以总结和探讨基于免疫表型结果的MPAL各亚型生物学特性及疗效和预后特征。.
方法: 选择2013年7月至2019年1月经本院诊治的MPAL患者，分析初诊时细胞形态学、免疫分型、细胞遗传学、分子生物学（MICM）及血常规等数据，病例随访截至末次出院时间。.
结果: 31例患者中，男性19例，女性12例，中位年龄41（12-76）岁；依据免疫分型结果，参照EGIL积分，髓-T混合表型16例（髓-T组），髓-B混合表型9例（髓-B组），T-B混合表型5例（T-B组），髓-T-B三系混合表型1例。各亚型比较，抗原表达特征为髓-B组HLA-DR阳性率、表达率最高，T-B组CD2阳性率显著高于髓-T组，同时T-B组CD7、cCD3（胞浆CD3）表达率高于髓-T组，髓-B组和T-B组全部病例均阳性表达cCD79a；T-B组中位WBC（81.92×109/L）显著高于其他两组（P<0.05）；92.6%的病例WT1定量结果高于10-4，髓-B组WT1表达水平显著低于其他两组（P<0.01），9例髓-B患者中，5例BCR-ABL阳性。28例随访患者中，21例达到完全缓解，首次获得完全缓解的中位时间为32.5（9-75）d，中位随访时间16个月（21天-6年）；分组结果显示，髓-B组完全缓解率为88.9%，中位总生存时间为40个月，均高于其他两组，T-B组完全缓解率和3年总生存率相对较低（50.0%，0）。.
结论: MPAL患者高表达WT1基因，基于免疫表型的MPAL各亚型有其独特的抗原表达特征。相较于髓-T和T-B患者，髓-B患者可获得较高的缓解率，预后良好。.
Keywords: flow cytometry; immunophenotype; mixed phenotype acute leukemia; molecular biology; prognosis.