title: Comparison of droplet digital PCR and conventional quantitative PCR for measuringEGFRgene mutation.
abstract: Early detection of epidermal growth factor receptor (EGFR) mutation, particularlyEGFRT790M mutation, is of clinical significance. The aim of the present study was to compare the performances of amplification refractory mutation system-based quantitative polymerase chain reaction (ARMS-qPCR) and droplet digital polymerase chain reaction (ddPCR) approaches in the detection ofEGFRmutation and explore the feasibility of using ddPCR in the detection of samples with low mutation rates.EGFRgene mutations in plasmid samples with different T790M mutation rates (0.1-5%) and 10 clinical samples were detected using the ARMS-qPCR and ddPCR approaches. The results demonstrated that the ARMS-qPCR method stably detected the plasmid samples (6,000 copies) with 5 and 1% mutation rates, while the ddPCR approach reliably detected those with 5% (398 copies), 1% (57 copies), 0.5% (24 copies) and 0.1% (average 6 copies) mutation rates. For the 10 clinical samples, the results for nine samples by the ARMS-qPCR and ddPCR methods were consistent; however, the sample N006, indicated to beEGFRwild-type by ARMS-qPCR, was revealed to have a clearEGFRT790M mutation with seven copies of mutant alleles in a background of 6,000 wild-type copies using ddPCR technology. This study demonstrates the feasibility of applying the ddPCR system to detectEGFRmutation and identified the advantage of ddPCR in the detection of samples with a lowEGFRmutation abundance, particularly the secondaryEGFRT790M resistance mutation, which enables early diagnosis before acquired resistance to tyrosine kinase inhibitors becomes clinically detectable.
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: B O
authors.initials: BO
authors.lastname: Zhang
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: Chun-Wei
authors.initials: CW
authors.lastname: Xu
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Shao
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: Huai-Tao
authors.initials: HT
authors.lastname: Wang
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: Yong-Fang
authors.initials: YF
authors.lastname: Wu
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: Ye-Ying
authors.initials: YY
authors.lastname: Song
authors.affiliation: Department of Pathology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing 100071, P.R. China.
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Li
authors.affiliation: Wuhan YZY Medical Science and Technology Co., Ltd., Wuhan, Hubei 430075, P.R. China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Wuhan YZY Medical Science and Technology Co., Ltd., Wuhan, Hubei 430075, P.R. China.
authors.forename: Wen-Jing
authors.initials: WJ
authors.lastname: Wang
authors.affiliation: Wuhan YZY Medical Science and Technology Co., Ltd., Wuhan, Hubei 430075, P.R. China.
authors.forename: Li-Qiong
authors.initials: LQ
authors.lastname: Li
authors.affiliation: Wuhan YZY Medical Science and Technology Co., Ltd., Wuhan, Hubei 430075, P.R. China.
authors.forename: Cong-Li
authors.initials: CL
authors.lastname: Cai
keywords: droplet digital polymerase chain reaction; epidermal growth factor receptor gene mutation; non-small cell lung cancer; quantitative polymerase chain reaction