Brassesco María Sol, Cortez Maria Angélica, Valera Elvis Terci, Engel Edgard Eduard, Nogueira-Barbosa Marcello Henrique, Becker Aline Paixão, Scrideli Carlos Alberto, Tone Luiz Gonzaga
Division of Pediatric Oncology, Department of Pediatrics, School of Medicine of Ribeirão Preto, University of São Paulo, Bloco G. Av. Bandeirantes, 3900, Bairro Monte Alegre, CEP 14048-900, Ribeirão Preto - São Paulo, Brazil.
Cancer Genet Cytogenet. 2010 Jan 15;196(2):189-93. doi: 10.1016/j.cancergencyto.2009.10.001.
Synovial sarcomas are high-grade malignant mesenchymal tumors that account for 10% of all soft-tissue sarcomas. Almost 95% of these tumors are characterized by a nonrandom chromosomal abnormality, t(X;18)(p11.2;q11.2), that is observed in both biphasic and monophasic variants. In this article, we present the case of a 57-year-old woman diagnosed with high-grade biphasic synovial sarcoma in which conventional cytogenetic analysis revealed the constant presence of a unique t(18;22)(q12;q13), in addition to trisomy 8. The rearrangement was confirmed by fluorescence in situ hybridization. The use of the whole chromosome painting probes WCPX did not detect any rearrangements involving chromosome X, although reverse-transcriptase polymerase chain reaction (PCR) analysis demonstrated the conspicuous presence of a SYT/SXX1 fusion gene. Spectral karyotyping (SKY) was also performed and revealed an insertion of material from chromosome 18 into one of the X chromosomes at position Xp11.2. Thus, the karyotype was subsequently interpreted as 47,X,der(X)ins(X;18)(p11.2;q11.2q11.2),der(18)del(18)(q11.2q11.2)t(18;22)(q12;q13),der(22)t(18;22). Real-time PCR analysis of BCL2 expression in the tumor sample showed a 433-fold increase. This rare finding exemplifies that thorough molecular-cytogenetic analyses are required to elucidate complex and/or cryptic tumor-specific translocations.
滑膜肉瘤是高级别恶性间叶组织肿瘤，占所有软组织肉瘤的10%。这些肿瘤中近95%具有非随机染色体异常t(X;18)(p11.2;q11.2)的特征，在双相型和单相型变体中均可观察到。在本文中，我们报告了一例57岁女性被诊断为高级别双相型滑膜肉瘤的病例，其中常规细胞遗传学分析显示，除了8号染色体三体之外，还始终存在独特的t(18;22)(q12;q13)。荧光原位杂交证实了这种重排。使用全染色体涂染探针WCPX未检测到涉及X染色体的任何重排，尽管逆转录聚合酶链反应(PCR)分析显示明显存在SYT/SXX1融合基因。还进行了光谱核型分析(SKY)，结果显示18号染色体的物质插入到一条X染色体的Xp11.2位置。因此，随后的核型被解释为47,X,der(X)ins(X;18)(p11.2;q11.2q11.2),der(18)del(18)(q11.2q11.2)t(18;22)(q12;q13),der(22)t(18;22)。肿瘤样本中BCL2表达的实时PCR分析显示增加了433倍。这一罕见发现表明，需要进行全面的分子细胞遗传学分析以阐明复杂和/或隐匿的肿瘤特异性易位。
