Shahi Farhad, Alishahi Razieh, Pashaiefar Hossein, Jahanzad Isa, Kamalian Naser, Ghavamzadeh Ardeshir, Yaghmaie Marjan
Dept. of Hematology and Medical Oncology, Cancer Research Center, Cancer Institute, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran.
Dept. of Biology, Faculty of Sciences, International Pardis, University of Guilan, Rasht, Iran.
Iran J Pathol. 2017 Summer;12(3):209-217. Epub 2017 Jul 1.
BACKGROUND & OBJECTIVE: Soft tissue sarcomas (STS) constitute an uncommon and heterogeneous group of tumors of mesenchymal origin and various cytogenetic abnormalities ranging from distinct genomic rearrangements, such as chromosomal translocations and amplifications, to more intricate rearrangements involving multiple chromosomes. Fluorescence in situ hybridization (FISH) can be used to identify these chromosomal translocations and amplifications, and sub classify STS precisely. The current study aimed at investigating the usefulness of FISH, as a diagnostic ancillary aid, to detect cytogenetic abnormalities such as (murine double minute 2 amplification and (C/EBP homologous protein) rearrangement in liposarcoma, as well as (synaptotagmin rearrangement in synovial sarcoma.
The FISH technique was used to analyze 17 specimens of liposarcoma for amplification and rearrangement, and 10 specimens of synovial sarcoma for rearrangement. The subtypes of liposarcoma and synovial sarcomas were reclassified according to the FISH results and compared with those of the respective histological findings.
According to the FISH results in 17 liposarcoma cases, well-differentiated liposarcoma(WDLPS), dedifferentiated liposarcoma (DDLPS), and myxoidliposarcoma (MLPS)subtypes were 41%, 53%, and 6%, respectively. In different subtypes of liposarcoma, a total of 30% mismatches were observed between pathologic and cytogenetic results. According to the histological findings from FISH analysis, rearrangement was found only in three out of 10 (30%) synovial sarcomas.
The detection of cytogenetic abnormalities in patients with liposarcoma and synovial sarcoma by FISH technique provides an important objective tool to confirm sarcoma diagnosis and sub classification of specific sarcoma subtypes in such patients.
软组织肉瘤（STS）是一组罕见且异质性的间充质起源肿瘤，存在各种细胞遗传学异常，从明显的基因组重排，如染色体易位和扩增，到涉及多条染色体的更复杂重排。荧光原位杂交（FISH）可用于识别这些染色体易位和扩增，并精确对STS进行亚分类。本研究旨在探讨FISH作为一种诊断辅助手段，检测脂肪肉瘤中的细胞遗传学异常，如鼠双微体2扩增和（C/EBP同源蛋白）重排，以及滑膜肉瘤中的（突触结合蛋白重排）的实用性。
采用FISH技术分析17例脂肪肉瘤标本的扩增和重排情况，以及10例滑膜肉瘤标本的重排情况。根据FISH结果对脂肪肉瘤和滑膜肉瘤的亚型进行重新分类，并与各自的组织学检查结果进行比较。
根据17例脂肪肉瘤的FISH结果，高分化脂肪肉瘤（WDLPS）、去分化脂肪肉瘤（DDLPS）和黏液样脂肪肉瘤（MLPS）亚型分别为41%、53%和6%。在不同亚型的脂肪肉瘤中，病理结果与细胞遗传学结果之间共观察到30%的不匹配。根据FISH分析的组织学结果，在10例滑膜肉瘤中仅3例（30%）发现重排。
通过FISH技术检测脂肪肉瘤和滑膜肉瘤患者的细胞遗传学异常，为这类患者确诊肉瘤及对特定肉瘤亚型进行亚分类提供了重要的客观工具。
