Mansoor Neelum, Rafiq Naila, Jamal Saba, Ehsan Aamir
Neelum Mansoor, FCPS. Section Head Cytogenetics, Indus Hospital and Health Network, Karachi, Pakistan.
Naila Rafiq, FCPS. Consultant Pediatric Hematology-Oncology, Indus Hospital and Health Network, Karachi, Pakistan.
Pak J Med Sci. 2024 Jan;40(2ICON Suppl):S47-S52. doi: 10.12669/pjms.40.2(ICON).8946.
Chromosome-1 abnormalities (C1As) are common genetic aberrations in hematological malignancies. We sought to evaluate significance of these abnormalities with reference to clinical characteristics and survival outcome in a pediatric B-Lymphoblastic Leukemia (B-ALL) cohort.
This is a retrospective study conducted in cytogenetic section of Indus Hospital and Health Network. Data was retrieved from October 2020 to July 2022 for childhood B-ALL cases exhibiting C1As. Chromosome analysis was performed on Cytovision MB8 using G-banded metaphases derived from unstimulated bone marrow culture. Results were recorded according to the International System for Human Cytogenetic Nomenclature (ISCN-2020). Data analyzed using SPSS, version 24.0.
C1As were observed in 60/450 (13.3%) cases of B-ALL. Among C1As, 29 (48%) cases had t(1;19). There were 13 (45%) balanced and 16 (55%) unbalanced translocations. The aberrations without t(1;19) were seen in 31 (52%) cases including 1q duplication with hyperdiploidy in 14 (45%) cases. The median age for C1As with and without t(1;19) was eight years and six years while the median leukocyte count was 32 x 10/L vs. 17 x 10/L. Event-free survival (EFS) for cases with and without t(1;19) was 69% and 74.2% respectively.
Despite the fact that the t(1;19) positive group had a higher median age, a higher white cell count and more CNS positives, the difference in EFS is statistically insignificant when compared to the t(1;19) negative cases. Furthermore, we found a survival difference between balanced and unbalanced t(1;19) groups, which is statistically insignificant but warrants large-scale prospective studies for further understanding.
1号染色体异常（C1As）是血液系统恶性肿瘤中常见的基因畸变。我们试图参照儿科B淋巴细胞白血病（B-ALL）队列的临床特征和生存结果来评估这些异常的意义。
这是一项在印度河医院及健康网络细胞遗传学科室进行的回顾性研究。检索了2020年10月至2022年7月期间表现出C1As的儿童B-ALL病例的数据。使用来自未刺激骨髓培养的G显带中期相在Cytovision MB8上进行染色体分析。结果根据国际人类细胞遗传学命名系统（ISCN-2020）记录。使用SPSS 24.0版进行数据分析。
在450例B-ALL病例中有60例（13.3%）观察到C1As。在C1As中，29例（48%）病例有t(1;19)。有13例（45%）平衡易位和16例（55%）不平衡易位。31例（52%）病例出现了没有t(1;19)的畸变，其中14例（45%）病例为伴有超二倍体的1q重复。有t(1;19)和没有t(1;19)的C1As病例的中位年龄分别为8岁和6岁，而中位白细胞计数分别为32×10⁹/L和17×10⁹/L。有t(1;19)和没有t(1;19)的病例的无事件生存率（EFS）分别为69%和74.2%。
尽管t(1;19)阳性组的中位年龄较高、白细胞计数较高且中枢神经系统阳性更多，但与t(1;19)阴性病例相比，EFS的差异在统计学上不显著。此外，我们发现平衡和不平衡t(1;19)组之间存在生存差异，这在统计学上不显著，但需要大规模前瞻性研究以进一步了解。
