Open AccessTumor volume determines the feasibility of cell‐free DNA sequencing for mutation detection in non‐small cell lung cancer
Author(s) -
Ohira Tatsuo,
Sakai Kazuko,
Matsubayashi Jun,
Kajiwara Naohiro,
Kakihana Masatoshi,
Hagiwara Masaru,
Hibi Masaaki,
Yoshida Koichi,
Maeda Junichi,
Ohtani Keishi,
Nagao Toshitaka,
Nishio Kazuto,
Ikeda Norihiko
Publication year - 2016
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.13068
Subject(s) - digital polymerase chain reaction , microbiology and biotechnology , dna sequencing , kras , dna , mutation , amplicon , lung cancer , cold pcr , cancer , biology , polymerase chain reaction , cancer research , medicine , gene , pathology , point mutation , genetics
Next‐generation sequencing ( NGS ) and digital PCR technologies allow analysis of the mutational profile of circulating cell‐free DNA (cf DNA ) in individuals with advanced lung cancer. We have now evaluated the feasibility of cf DNA sequencing for mutation detection in patients with non‐small cell lung cancer at earlier stages. A total of 150 matched tumor and serum samples were collected from non‐small cell lung cancer patients at stages IA – IIIA . Amplicon sequencing with DNA extracted from tumor tissue detected frequent mutations in EGFR (37% of patients), TP 53 (39%), and KRAS (10%), consistent with previous findings. In contrast, NGS of cf DNA identified only EGFR , TP 53 , and PIK 3 CA mutations in three, five, and one patient, respectively, even though adequate amounts of cf DNA were extracted (median of 4936 copies/ mL serum). Next‐generation sequencing showed a high accuracy (98.8%) compared with droplet digital PCR for cf DNA mutation detection, suggesting that the low frequency of mutations in cf DNA was not due to a low assay sensitivity. Whereas the yield of cf DNA did not differ among tumor stages, the cf DNA mutations were detected in seven patients at stages IIA – IIIA and at T2b or T3. Tumor volume was significantly higher in the cf DNA mutation‐positive patients than in the negative patients at stages T2b–T4 (159.1 ± 58.0 vs . 52.5 ± 9.9 cm 3 , P = 0.014). Our results thus suggest that tumor volume is a determinant of the feasibility of mutation detection with cf DNA as the analyte.