Willeke F, Mechtersheimer G, Schwarzbach M, Weitz J, Lehnert T, Herfarth C, Otto H F, von Knebel Doeberitz M, Ridder R
Chirurgische Universitätsklinik, Rupercht Karls Universität Heidelberg.
Verh Dtsch Ges Pathol. 1998;82:215-9.
Various mesenchymal malignancies with a spindle cell morphology may mimic monophasic synovial sarcomas. We analysed, whether detection of SYT-SSX1/2 fusion transcripts, present as a consequence of a specific translocation [t(X;18)(p11.2;q11.2)] found in synovial sarcomas, are useful to confirm the diagnosis of synovial sarcoma. A nested RT-PCR protocol was established for the detection of SYT-SSX1/2 fusion transcripts. After RNA extraction of snap frozen tissue reverse transcription was carried out. In a nested PCR, the resulting cDNA samples were amplified and visualized on agarose gels. DNA sequencing of PCR products enabled the assignment of fusion transcripts to either the SYT-SSX1 or the SYT-SSX2 variant. We detected SYT-SSX1/2 fusion transcripts in seven monophasic and three biphasic synovial sarcomas. 20 out of 21 control tumour including leiomyosarcomas, malignant peripheral nerve sheath tumours, gastrointestinal stromal sarcomas and fibrosarcomas were negative in RT-PCR analysis. One case of recurrent spindle cell sarcoma originally classified as a fibrosarcoma revealed a SYT-SSX2 fusion transcript. These data provide further evidence that the RT-PCR amplification of SYT-SSX1/2 fusion transcripts permits the specific identification of synovial sarcomas. This diagnostic approach may be especially useful in cases with equivocal histomorphology.
各种具有梭形细胞形态的间充质恶性肿瘤可能会模仿单相滑膜肉瘤。我们分析了滑膜肉瘤中因特定易位[t(X;18)(p11.2;q11.2)]而出现的SYT-SSX1/2融合转录本的检测是否有助于确诊滑膜肉瘤。建立了一种巢式逆转录聚合酶链反应（RT-PCR）方法来检测SYT-SSX1/2融合转录本。对速冻组织进行RNA提取后进行逆转录。在巢式PCR中，将得到的cDNA样本进行扩增并在琼脂糖凝胶上可视化。对PCR产物进行DNA测序，可将融合转录本归为SYT-SSX1或SYT-SSX2变体。我们在7例单相和3例双相滑膜肉瘤中检测到SYT-SSX1/2融合转录本。在21例对照肿瘤（包括平滑肌肉瘤、恶性外周神经鞘瘤、胃肠道间质肉瘤和纤维肉瘤）中，20例在RT-PCR分析中呈阴性。1例最初分类为纤维肉瘤的复发性梭形细胞肉瘤显示出SYT-SSX2融合转录本。这些数据进一步证明，SYT-SSX1/2融合转录本的RT-PCR扩增可实现滑膜肉瘤的特异性鉴定。这种诊断方法在组织形态学不明确的病例中可能特别有用。
