Chai Yi-huan, Lü Hui, Li Jian-qin, Lu Jun, Xiao Pei-fang, He Ya-xiang, Shao Xue-jun
Department of Pediatric Hematology/Oncology, Soochow University Children's Hospital, Suzhou 215003, China.
Zhonghua Er Ke Za Zhi. 2007 Sep;45(9):684-6.
In childhood acute lymphoblastic leukemia (ALL), cytogenetics plays an important role in diagnosis, allocation of treatment and prognosis. On the basis of the conventional cytogenetic analysis, molecular methods have improved pediatric hematologists/oncologist's ability to accurately and rapidly perform risk-stratification on patients with childhood ALL during the last few years. The aim of the present study was to assess the demography of cytogenetic abnormalities in childhood ALL.
The study subjects consisted of 124 newly diagnosed ALL patients younger than 16 years of age, who were diagnosed at the Department of Pediatric Hematology/Oncology, Soochow University Children's Hospital. The diagnosis and FAB subtypes of ALL was determined by Wright-Giemsa-stained bone marrow smears and cytochemical staining. Immunophenotyping of the bone marrow samples was performed by flow cytometry. Multiplex polymerase chain reaction (Multiplex PCR) analysis was performed to detect the 29 most common leukemia translocations for routine molecular diagnostic hematopathology practice, and complement the information gained from conventional cytogenetic analysis.
Cytogenetic analysis was successful in 112 of 124 children with ALL. Sixty-eight (60%) of them had clonal chromosomal abnormalities. Numerical imbalances consisted of hyperdiploid (> 47 chromosomes, 36 cases), hypodiploid (< 46 chromosomes, 14 cases), pseudodiploidy (18 cases). Chromosomal translocations were observed in 13 patients by conventional cytogenetic analysis. Three cases were found positive for 4; 11 translocation, 3 cases for 9; 22 translocation, 1 case for 1; 19 translocation and 6 cases for other rare translocations. Multiplex-PCR analysis detected 116 of the 124 ALL patients. Thirteen cases of TEL-AML1, 10 cases of rearrangement in the MLL gene, 4 cases of E2A-PBX1, 4 cases of E2A-HLF, 3 cases of BCR-ABL, 2 cases of TLS-ERG, 32 cases of HOX11 were detected by Multiplex PCR in B-lineage leukemias. SIL-TAL1 had been found in 4 of 7 of T-lineage leukemias.
Sixty-eight cases of ALL showed chromosomal aberrations. Multiplex PCR positivity was detected in 59 (50%) of the 116 ALL patients studied. Multiplex PCR combined with chromosomal analysis uncovered chromosomal abnormalities in 95 of 124 (77%) of ALL patients and supplemented each other in detecting chromosomal abnormalities.
在儿童急性淋巴细胞白血病（ALL）中，细胞遗传学在诊断、治疗分配及预后方面发挥着重要作用。在过去几年里，基于传统细胞遗传学分析，分子方法提高了儿科血液科医生/肿瘤医生对儿童ALL患者进行准确、快速风险分层的能力。本研究旨在评估儿童ALL中细胞遗传学异常的人口统计学特征。
研究对象为124例新诊断的16岁以下ALL患者，他们在苏州大学儿童医院儿科血液/肿瘤科确诊。ALL的诊断及FAB亚型通过瑞氏-吉姆萨染色骨髓涂片及细胞化学染色确定。骨髓样本的免疫表型分析通过流式细胞术进行。采用多重聚合酶链反应（Multiplex PCR）分析检测29种最常见的白血病易位，用于常规分子诊断血液病理学实践，并补充从传统细胞遗传学分析中获得的信息。
124例ALL儿童中有112例成功进行了细胞遗传学分析。其中68例（60%）存在克隆性染色体异常。数量失衡包括超二倍体（>47条染色体，36例）、亚二倍体（<46条染色体，14例）、假二倍体（18例）。通过传统细胞遗传学分析在13例患者中观察到染色体易位。发现3例4；11易位阳性，3例9；22易位阳性，1例1；19易位阳性，6例其他罕见易位阳性。Multiplex-PCR分析检测了124例ALL患者中的116例。在B系白血病中，Multiplex PCR检测到13例TEL-AML1、10例MLL基因重排、4例E2A-PBX1、4例E2A-HLF、3例BCR-ABL、2例TLS-ERG、32例HOX11。在7例T系白血病中有4例检测到SIL-TAL1。
68例ALL显示染色体畸变。在116例研究的ALL患者中，59例（50%）检测到Multiplex PCR阳性。Multiplex PCR与染色体分析相结合，在124例ALL患者中的95例（77%）发现了染色体异常，在检测染色体异常方面相互补充。
