T幼淋细胞白血病小细胞变异型2例临床分析

Clinical Analysis of Two Patients with Small Cell Variant of T-Cell Prolymphocytic Leukemia

目的探讨T幼淋细胞白血病(T-cell prolymphocytic leukemia,T-PLL)小细胞变异型的临床特征。方法对2例外周血淋巴细胞显著增高的病例,进行细胞形态学、活检病理学、骨髓免疫分型、染色体核型、荧光原位杂交(FISH)、T细胞受体(TCR)基因重排及二代基因测序(NGS)检查。结果2例病例确诊为T-PLL,初诊时外周血和骨髓形态以成熟小淋巴细胞为主,胞体小,胞质少,胞核不规则,异型性明显,核仁不明显,符合T-PLL小细胞变异型。例1骨髓和淋巴结病理结果为CD4+CD8-T细胞淋巴瘤。2例骨髓免疫表型均为CD4+CD8-,表达泛T细胞标记CD2、CD3、CD5、CD7,且不表达CD16、CD56、CD1a、TdT、TCRγ/δ。2例TCRγ/β基因重排均为阳性。2例染色体均为正常核型,例2的FISH结果为TP53基因缺失阳性。例1的NGS结果为STAT5B、JAK3、ATM基因突变,例2的NGS结果为TP53基因突变。2例均未接受化疗,例2出院后随访1个月死亡。结论确诊T-PLL需结合临床表现及细胞形态学、免疫分型、分子生物学、细胞遗传学等实验室检查结果综合判断,外周血细胞形态对T-PLL的诊断最为关键,免疫分型对T-PLL鉴别诊断有意义,细胞遗传学检查结果可为疾病预后判断提供依据。

0bjective To investigate clinical characteristics of the patients with small cell variant of T-cell prolymphocytic leukaemia(T-PLL).Methods Cytomorphologic,Pathological biopsy,Bone marrow immunophenotypic examination,Karyotype analysis,fluorescence in situ hybridization(FISH),T-cell receptor(TCR)gene rearrangement detection and second generation gene sequencing(NGS)were used to verify the diagnosis for 2 patients with lymphocytosis.Results Two cases were diagnosed as T-PLL.At the initial diagnosis,the morphology of peripheral blood and bone marrow was mainly mature small lymphocytes,with small cell body,few cytoplasm,irregular nucleus,obvious atypia and unclear nucleolus,which was consistent with the small cell variant of T-PLL.The pathological results of bone marrow and lymph nodes in case 1 were CD4+CD8-T cell lymphoma.The bone marrow immunophenotype of the two patients was CD4+CD8-,expressed pan T cell markers CD2,CD3,CD5 and CD7,and did not express CD16,CD56,CD1a,TDT and TCRγ/δ.Two cases of TCRγ/βgene rearrangement was positive.The chromosomes of two cases were normal karyotype,and the FISH result of case 2 was TP53 gene deletion positive.The NGS result of case 1 was STAT5B,JAK3 and ATM gene mutation,and the NGS result of case 2 was TP53 gene mutation.Both cases did not receive chemotherapy,and case 2 died after 1 month follow-up.Conclusion The diagnosis of T-PLL needs to be comprehensively judged in combination with clinical manifestations and laboratory examination results such as cell morphology,immunotyping,molecular biology and cytogenetics.The morphology of peripheral blood cells is the key to the diagnosis of T-PLL.Immunotyping is meaningful for the differential diagnosis of T-PLL.The results of cytogenetic examination can provide a basis for the prognosis of the disease.