前面我们讲述了ctc的和（☜戳链接看漫画），身为肿瘤标志物家族鼎鼎有名的一员，循环肿瘤dna（circulating tumor dna, ctdna）也是不容小觑。作为细胞外游离dna（cell-free dna, cfdna）的一种，可存在于血液、脑脊液、尿液和唾液等体液中。鉴于目前临床最易于获取、研究最多的是血液样本，因此我们着重关注外周血中的dna……看看其中有何秘密……
这期我们便来聊聊，
ctdna的研究史！
# 参考文献 #
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[8] 非小细胞肺癌血液egfr基因突变检测中国专家共识.
[9] non-small cell lung cancer, version 9.2017, nccn clinical practice guidelines in oncology.
