No current circulating tumor cell (CTC) enumeration system provides better prognostic value than CellSearch. We have developed a novel semi-automated CTC enumeration system (fluidic cell microarray chip system, FCMC) that captures CTC independently of tumor-specific markers or physical properties. This system was validated in preclinical studies and in blood samples from 20 healthy donors and 22 breast cancer patients in this study. Using spike-in samples, a statistically higher detection rate (p = 0.010) of MDA-MB-231 cells and an equivalent detection rate (p = 0.497) of MCF-7 cells were obtained with FCMC in comparison with CellSearch. The number of CTC detected in samples from patients that was above a threshold value as determined from healthy donors was evaluated. The CTC number detected using FCMC was significantly higher than that using CellSearch (p = 0.00037). CTC numbers obtained using either FCMC or CellSearch had prognostic value, as assessed by time-to-treatment-failure. The hazard ratio between CTC+ and CTC- was 4.043 in CellSearch (95% CI, 1.248 to 13.10; p = 0.01985); in contrast, it was 10.97 in FCMC (95% CI, 2.18 to 55.21; p = 0.003662). CTC detected using FCMC have the potential to be a better prognostic factor than CTC detected using CellSearch.

Citation Format: Takeshi Sawada, Jungo Araki, Toshinari Yamashita, Manami Masubuchi, Tsuneko Chiyoda, Mayu Yunokawa, Kumiko Hoshi, Shoichi Tao, Shohei Yamamura, Shouki Yatsushiro, Kaori Abe, Masatoshi Kataoka, Tatsu Shimoyama, Yoshiharu Maeda, Katsumasa Kuroi, Kenji Tamura, Tsuneo Sawazumi, Hironobu Minami, Yoshihiko Suda, Fumiaki Koizumi. Prognostic impact of CTC detected using a novel fluidic cell microarray chip CTC detection system in patients with breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 500.