Xu Jiachen, Wu Wei, Wu Chunyan, Mao Yong, Qi Xiaowei, Guo Lin, Lu Renquan, Xie Shuhong, Lou Jiatao, Zhang Yu, Ding Yiyan, Guo Zijian, Zhang Li, Liang Naixin, Chen Peng, Zhang Cuicui, Tao Min, Yu Zhengyuan, Geng Hua, Xu Meilin, Shi Meiqi, Wang Li, Guo Wei, Zhao Jun, Li Jianjie, Shi Lixia, Zhang Yan, Qin Zhonghua, Chen Jun, Liu Jinghao, Ren Jing, Yang Zhenlin, Pan Xin, Lv Zhaoqing, Dong Hao, Zhang Jie, Ou Jiajia, Li Zhaoliang, Kaji Kavanaugh, Wang Yan, Wang Jie, Wang Zhijie
State Key Laboratory of Molecular Oncology, Department of Medical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Department of Pathology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China.
Transl Lung Cancer Res. 2021 Oct;10(10):3888-3901. doi: 10.21037/tlcr-21-564.
Developing liquid biopsy technology with higher sensitivity and specificity especially for low-frequency mutations remains crucial. This study demonstrated superior performance of the newly developed digital PCR (dPCR) kit for ctDNA-based p.T790M detection in metastatic non-small-cell lung cancer (NSCLC) against ARMS-PCR.
This large-scale, multi-centered diagnostic study recruited 1,045 patients including 1,029 patients diagnosed with advanced NSCLC and 16 patients with specific samples between April 1 2018 and November 30 2019. EGFR p.T790M in plasma samples from mNSCLC patients were tested using dPCR with ADx-ARMS PCR and Cobas Mutation Test V2 as comparator assays to confirm cut-off value for dPCR and evaluate its performance against ARMS-PCR-based assays. Efficacy was evaluated for patients with p.T790M detected by dPCR or ARMS-PCR, who underwent Osimertinib treatment.
The sensitivity, specificity, and concordance of dPCR against ADx-ARMS PCR was 98.15%, 88.66% and 90.16%, respectively for 1,026 plasma samples. Additional 9.26% patients were detected positive by dPCR. The majority of those samples had a mutation allele frequency between 0.1% and 1%. In 45 paired tissue and plasma samples, the sensitivity improved from 30.77% to 53.85% by dPCR with the specificity over 90%. The response of Osimertinib in 74 p.T790M-positive patients detected by dPCR, including 26 determined as negative by ARMS-PCR, were evaluated to have an ORR of 44.59% and a DCR of 90.54%.
dPCR is a sensitive and accurate tool for ctDNA-based p.T790M detection due to its significantly improved sensitivity without compromising specificity, and dPCR is equivalent to ARMS-PCR as a companion diagnostic tool while benefiting more patients under Osimertinib treatment.
Chinese Clinical Trial Registry identifier: ChiCTR2100043147.
开发具有更高灵敏度和特异性的液体活检技术，尤其是针对低频突变的技术，仍然至关重要。本研究证明了新开发的数字PCR（dPCR）试剂盒在检测转移性非小细胞肺癌（NSCLC）基于循环肿瘤DNA（ctDNA）的p.T790M突变方面，相对于扩增阻滞突变系统PCR（ARMS-PCR）具有卓越的性能。
这项大规模、多中心的诊断性研究在2018年4月1日至2019年11月30日期间招募了1045名患者，其中包括1029名被诊断为晚期NSCLC的患者和16名有特定样本的患者。使用dPCR对转移性非小细胞肺癌患者血浆样本中的表皮生长因子受体（EGFR）p.T790M进行检测，并将ADx-ARMS PCR和Cobas Mutation Test V2作为对照检测方法，以确定dPCR的临界值，并评估其相对于基于ARMS-PCR的检测方法的性能。对通过dPCR或ARMS-PCR检测到p.T790M且接受奥希替尼治疗的患者进行疗效评估。
对于1026份血浆样本，dPCR相对于ADx-ARMS PCR的灵敏度、特异性和一致性分别为98.15%、88.66%和90.16%。另外9.26%的患者通过dPCR检测为阳性。这些样本中的大多数突变等位基因频率在0.1%至1%之间。在45对组织和血浆样本中，dPCR的灵敏度从30.77%提高到53.85%，特异性超过90%。对通过dPCR检测到的74名p.T790M阳性患者（包括26名被ARMS-PCR判定为阴性的患者）使用奥希替尼的反应进行评估，客观缓解率（ORR）为44.59%，疾病控制率（DCR）为90.54%。
dPCR是一种用于基于ctDNA的p.T790M检测的灵敏且准确的工具，因为其在不影响特异性的情况下显著提高了灵敏度，并且dPCR作为伴随诊断工具与ARMS-PCR相当，同时使更多接受奥希替尼治疗的患者受益。
中国临床试验注册中心标识符：ChiCTR2100043147。
