Department of Thoracic Surgery, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305- 8577, Japan.
Department of Clinical Research and Regional Innovation, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
BMC Cancer. 2024 Oct 18;24(1):1291. doi: 10.1186/s12885-024-12945-9.
We developed a Rare Cell Sorter (RCS) for collecting single cell including circulating tumor cells (CTCs). This single-institution pilot study evaluated the ability of this device to detect tumor-like cells in patients with lung cancer and confirmed their genuineness based on the epidermal growth factor receptor (EGFR) mutation concordance with tissue samples.
This study included patients treated for lung cancer from September 2021 to August 2022 in University of Tsukuba Hospital. Peripheral blood samples were obtained before surgery or during periodic medical checks for patients treated with drugs. We used the RCS to capture cells based on size. The cells were stained, and the Hoechst-positive, CD45-negative, and epithelial celladhesion molecule (EpCAM)- positive cells were defined as CTCs, were collected. The presumptive CTCs were counted and tested using digital droplet polymerase chain reaction for EGFR mutations and compared with the tissue EGFR status to check concordance.
Eighteen patients were included in this study and CTCs were detected in 6 patients (33%). The CTCs from three patients showed EGFR mutation, and the EGFR mutation status of CTCs concorded with that of tissue samples in 83% of the cases (5/6). Only one CTC showed a different status from the tissue, and the concordance rate of EGFR status between CTCs and the tissue was 96% (24/25).
The ability of the RCS to detect CTCs in patients with lung cancer was demonstrated based on the concordance of EGFR status in this pilot study. This novel hybrid method of CTC recovery using the RCS has the potential to recover a wide range of CTCs regardless of EpCAM. Further validation through a large-scale study is needed.
我们开发了一种稀有细胞分选器（RCS），用于收集包括循环肿瘤细胞（CTC）在内的单细胞。这项单机构试点研究评估了该设备在肺癌患者中检测肿瘤样细胞的能力，并基于与组织样本的表皮生长因子受体（EGFR）突变一致性来确认其真实性。
本研究纳入了 2021 年 9 月至 2022 年 8 月在筑波大学医院接受肺癌治疗的患者。手术前或接受药物治疗的患者定期体检时采集外周血样本。我们使用 RCS 根据大小捕获细胞。对细胞进行染色，将 Hoechst 阳性、CD45 阴性和上皮细胞黏附分子（EpCAM）阳性的细胞定义为 CTC，并进行收集。对疑似 CTC 进行计数，并使用数字液滴聚合酶链反应检测 EGFR 突变，与组织 EGFR 状态进行比较，以检查一致性。
本研究纳入了 18 例患者，其中 6 例（33%）检测到 CTC。3 例患者的 CTC 显示 EGFR 突变，CTC 的 EGFR 突变状态与组织样本的一致性为 83%（5/6）。只有一个 CTC 的状态与组织不同，CTC 和组织之间的 EGFR 状态一致性为 96%（24/25）。
在这项试点研究中，基于 EGFR 状态的一致性，证明了 RCS 检测肺癌患者 CTC 的能力。这种使用 RCS 回收 CTC 的新型混合方法有可能回收广泛的 CTC，而不受 EpCAM 的影响。需要通过大规模研究进一步验证。
