Table 2.
CTCs as prognostic markers in lung cancer.
| Study | Technology | Sensitivity (% of patients positive for CTCs) | Prognostic significance |
|---|---|---|---|
| Hofman et al. (37) 208 NSCLC patients (stages I–IV) |
ISET | 50% | >50 CTCs corresponded with shorter OS and PFS |
| Tanaka et al. (35) 125 lung cancer patients (stages I–IV) 25 patients with non-malignant diseases |
CellSearch | 30% in all patients 71% in metastatic patients |
CTC count was higher in lung cancer than non-malignant patients. CTC count was higher in patient with distant metastasis |
| Kreb et al. (19) 101 NSCLC patients (Stages III–IV) |
CellSearch | 21% at baseline (32% at stage IV, 7% at stage IIIB) | >5 CTCs/7.5 ml blood predicted shorter PFS and OS. A reduction in CTC count after chemotherapy predicted improved survival |
| Dorsey et al. (72) 30 NSCLC patients received radiation therapy |
Telomerase-based assay | 65% before RT | CTC count decreased in patients responding to RT |
| Juan et al. (73) 37 NSCLC patients [Advanced stage (IIIB–IV)] |
CellSearch | 24% at baseline | No significant prognostic conclusion was made |
| Muinelo-Romay et al. (34) 43 NSCLC patients (stages IIIB and IV) |
CellSearch | 42% at baseline | >5 CTCs/7.5 ml blood at baseline predicted shorter PFS and OS. CTC count increase during chemotherapy correlated with worse PFS and OS |
| Punnoose et al. (33) 41 NSCLC patients (Advanced stage) |
CellSearch | 76% at baseline | Reduction in CTC count after chemotherapy predicted longer PFS |
| Sienel et al. (74) 62 NSCLC patients (stages I–III) |
Ficoll-Hypaque Centrifugation |
18% in pulmonary venous (PV) blood | Presence of CTCs in PV blood was associated with shorter survival especially in patients with lymph node involvement |
| Hashimoto et al. (75) 30 NSCLC patients (stages I–IV) |
CellSearch | 73% in PV blood before surgery | CTC count in PV blood significantly increased after surgery, which predicted lymphatic tumor invasion |
| Funaki et al. (76) 130 NSCLC patients (stages I–IV) |
RosetteSep kit | 74% in PV blood after tumor resection Circulating tumor microemboli (CTM) in 33% |
The presence of CTM in PV blood predicted worse PFS |
| Chudasama et al.(77) 20 NSCLC patients (stages III–IV) |
ScreenCell | 25% at baseline, 75% after endobronchial cryotherapy (EC) | CTC count increased after EC |
| Carlsson et al. (70) 104 NSCLC patients (stages I–IV) 25 patients with benign diseases |
HD-CTC assay | 50% positive to CTM | CTM along with clinical and imaging data can serve as predictor of malignant vs benign diseases |
| Pirozzi et al. (114) 45 NSCLC patients (stages I–III) |
Ficoll-Hypaque Centrifugation |
24% in PV blood | No association found between presence of CTCs and prognosis |
| Nel et al. (79) 43 NSCLC patients (stages IIB–IV) |
Ficoll-Paque CD45 magnetic depletion | 100% | Presence of mesenchymal markers CD133 and N-cadherin in CTCs predicated shorter PFS |
| Hou et al. (81) 97 SCLC patients |
CellSearch and ISET | CTCs in 85% CTM in 32% |
More than 50 CTCs/7.5 ml blood predicated shorter OS |
| Huang et al. (82) 26 SCLC patients |
CellSearch | Not reported Median CTC count at baseline is 75 (0–3430) |
CTC count decreased after chemotherapy CTC count at baseline and change of CTC numbers after treatment not associated with survival |