■RET抑制剂具有令人印象深刻的总体反应率,现在可用于NSCLC患者。然而,识别RET融合仍然是一个艰巨的挑战。大多数指南鼓励预先使用下一代测序(NGS),或者,荧光原位杂交(FISH)或逆转录酶聚合酶链反应(RT-PCR)时,NGS是不可能的或可用的。一起来看,单分析物检测RET融合的性能欠佳,尽管与鼓励普遍NGS的概念一致,目前正在扩大在晚期NSCLC患者中实施预测性生物标志物的一些临床实践差距。
■这种情况促使我们在RET融合阳性NSCLC(n=38)的大型多中心队列中评估了几种RET测定,以获得真实世界的数据。除了基于RNA的NGS(标准标准方法),所有阳性标本均采用两种不同的方法进行分离RETFISH检测,并通过RT-PCR检测.
■最常见的RET合作伙伴是KIF5B(78.9%),其次是CCDC6(15.8%)。两个RETNGS阳性但FISH阴性的样品含有KIF5B(15)-RET(12)融合。未通过RT-PCR鉴定的三个RET融合体是AKAP13(35)-RET(12),KIF5B(24)-RET(9)和KIF5B(24)-RET(11)。3例假阴性RT-PCR均为FISH阳性,表现出典型的分裂模式,并且在两种FISH检测中都含有非常高数量的阳性肿瘤细胞。Signet环细胞,沙玛尸体,经常观察到多形性特征(34.2%,39.5%,39.5%的肿瘤,分别)。
■深入了解不同RET测试方法的优缺点可以帮助临床和分子肿瘤委员会实施和维持明智的算法,以快速有效地检测NSCLC患者的RET融合。FISH和RT-PCR的RET假阴性结果的可能性加强了NSCLC患者对前期NGS的需求。
UNASSIGNED: RET inhibitors with impressive overall response rates are now available for patients with NSCLC, yet the identification of RET fusions remains a difficult challenge. Most guidelines encourage the upfront use of next-generation sequencing (NGS), or alternatively, fluorescence in situ hybridization (
FISH) or reverse transcriptase-polymerase chain reaction (RT-PCR) when NGS is not possible or available. Taken together, the suboptimal performance of single-analyte assays to detect RET fusions, although consistent with the notion of encouraging universal NGS, is currently widening some of the clinical practice gaps in the implementation of predictive biomarkers in patients with advanced NSCLC.
UNASSIGNED: This situation prompted us to evaluate several RET assays in a large multicenter cohort of RET fusion-positive NSCLC (n = 38) to obtain real-world data. In addition to RNA-based NGS (the criterion standard method), all positive specimens underwent break-apart RET
FISH with two different assays and were also tested by an RT-PCR assay.
UNASSIGNED: The most common RET partners were KIF5B (78.9%), followed by CCDC6 (15.8%). The two RET NGS-positive but
FISH-negative samples contained a KIF5B(15)-RET(12) fusion. The three RET fusions not identified with RT-PCR were AKAP13(35)-RET(12), KIF5B(24)-RET(9) and KIF5B(24)-RET(11). All three false-negative RT-PCR cases were
FISH-positive, exhibited a typical break-apart pattern, and contained a very high number of positive tumor cells with both
FISH assays. Signet ring cells, psammoma bodies, and pleomorphic features were frequently observed (in 34.2%, 39.5%, and 39.5% of tumors, respectively).
UNASSIGNED: In-depth knowledge of the advantages and disadvantages of the different RET testing methodologies could help clinical and molecular tumor boards implement and maintain sensible algorithms for the rapid and effective detection of RET fusions in patients with NSCLC. The likelihood of RET false-negative results with both FISH and RT-PCR reinforces the need for upfront NGS in patients with NSCLC.