Table 1.
CTCs in early breast cancer.
| Authors [Reference] | Study Design | Method | Findings |
|---|---|---|---|
| Riethdorf, S., et al., 2010 [32] | CTCs before and after neoadjuvant chemotherapy | CellSearch | 1 or more CTC detected in 21.6% patients before NACT. 1 or more CTC detected in 10.6% patients after NACT. No correlation between CTC detection and clinicopathological features. No association between CTC levels and treatment response. |
| Xenidis, N., et al., 2009 [33] | CK-19 mRNA-positive CTCs before and after adjuvant chemotherapy | RT-PCR | CK-19 mRNA+ CTCs detected in 41% patients before adjuvant chemotherapy. CK-19 mRNA+ CTCs detected in 32.7% patients after adjuvant chemotherapy. CK-19 mRNA+ CTCs associated with more than 3 involved axillary lymph nodes. CK-19 mRNA+ CTCs post-adjuvant chemotherapy associated with chemotherapy-resistant residual disease. CK-19 mRNA+ CTCs post-adjuvant chemotherapy associated with decreased DFS and OS. |
| Sandri, M.T., et al., 2010 [34] | CTCs before and after surgery | CellSearch | CTCs detected in 30% of patients before and after surgery.CTCs detected pre-surgery associated with positive vascular invasion. |
| Serrano, M.J., et al., 2012 [35] | CTCs before and after neoadjuvant chemotherapy | Ficoll gradient Immunomagnetic cell separation CK 7, 8, 18, 19, anti-CK FITC |
CTCs detected in 71% patients pre-NACT. CTCs detected in 54% patients post-NACT. CTCs detected pre- and post-NACT associated with increased risk of recurrence. |
| Pierga, J.Y., et al., 2008 [36] | CTCs in patients with large operable or locally advanced breast cancer before and after neoadjuvant chemotherapy | CellSearch | CTCs detected in 23% patients pre-NACT. CTCs detected in 17% patients post-NACT. No association between CTC and primary tumor response. CTCs independently associated with early relapse. |
| Bidard, F.C., et al., 2013 [37] | CTCs before and after NACT | CellSearch | CTCs detected pre-NACT associated with disease metastatic free survival (DMFS)and OS. CTCs detected post-NACT had no impact. CTCs independently associated with significantly worse outcome during first 3 years of follow-up. |
| Lucci, A., et al., 2012 [38] | CTCs at time of surgery in chemonaive early stage breast cancer | CellSearch | CTCs detected in 24% of patients at surgery. CTCs associated with decreased PFS and OS. |
| Hall, C., et al., 2015 [39] | CTCs after NACT in TNBC | CellSearch | CTCs detected in 30% of patients after NACT. CTCs associated with decreased RFS and OS. |
| Rack, B., et al., 2014 [40] | CTCs before and after adjuvant chemotherapy | CellSearch | CTCs detected in 21.5% of patients pre-adjuvant chemotherapy. CTCs detected in 22.1% of patients post-adjuvant chemotherapy. CTCs before and after adjuvant therapy independently associated with decreased disease-free survival and overall survival. |
| Pierga, J.Y., et al., 2015 [41] | CTCs in HER2+ IBC before, during, after NACT | CellSearch | CTCs at baseline independently associated with 3-year disease free survival. No CTC detected at baseline = 81% DFS. 1 or more CTC detected at baseline = 43% DFS. |
| Pierga, J.Y., et al., 2017 [42] | CTCs in HER2+ IBC before, during, after NACT (pooled analysis) | CellSearch | CTCs detected in 39% of patients at baseline. CTCs detected in 9% of patients after 4 cycles of chemotherapy. No correlation between CTC and pCR. CTCs detected as baseline associated with decreased 3-year DFS and OS. |
| Sparano, J., et al., 2018 [43] | CTCs at 5-years after diagnosis in ER+, HER2- | CellSearch | CTCs detected in 5.1% of patients 5 years after diagnosis.CTCs independently associated with increased risk of recurrence 5 years after diagnosis. |
| Goodman, C.R., et al., 2018 [44] | CTCs and radiotherapy in early stage breast cancer | CellSearch | At least 1 CTC and treated with radiotherapy associated with increased RFS, DFS, and OS. |
| Trapp, E., et al., 2019 [45] | CTCs before and 2 years after adjuvant chemotherapy | CellSearch | CTCs detected in 18.2% of patients 2 years after chemotherapy. CTCs detected 2 years after chemotherapy associated with decreased OS and DFS. |
| Rossi, T., et al., 2020 [46] | Copy number alterations of CTCs pre-surgery, 1-month post-surgery, and 6-months post-surgery | OncoQuick DEPArray |
CTCs presented different levels of copy number alterations based on timepoint and cancer subtype. CTCs 6 months post-surgery shared copy number alterations with primary tumor. |
CTCs, circulating tumor cells; DFS, disease-free survival; NACT, neoadjuvant chemotherapy; OS, overall survival; PFS, progression-free survival; RFS, recurrence-free survival.