Table 1.
Detection of circulating and disseminated tumour cells in oral squamous cell carcinoma and head neck squamous cell cancer
| Source | Entity | n | Assay system | CTC-positive (%) | DTC-positive (%) | Clinical relevance | Number of analysed OSCC | Ref. yr of release |
| PB | OSCC | 20 | RT-PCR: CK19 mRNA | 20.0 | Detection of CK19-mRNA when tumour is incised | OSCC only | [85], 2000 | |
| PB | HNSCC | 77 | RT-PCR: CK19 mRNA | 2.1 | No significance for CTCs | Various sites n = 13 OSCC n = 23 oropharyngeal | [79], 2001 | |
| PB/ CVB BM | HNSCC | 40 | ICC: Keratins CK1-8, 10, 14-16 and 19 RT-PCR: E48 mRNA | 10.0 (PCR) 20.0 (ICC) | 20.0 (PCR) 32.0 (ICC) | E48 mRNA and DMFS/DFS preoperative in BM (P = 0.001/P = 0.002) and CVB (P < 0.001/P = 0.013) E48-mRNA and DMFS/DFS intraoperative in CVB (P = 0.026/0.001) ICC and DMFS preoperative in BM (P = 0.0006) and CVB (P < 0.001) ICC and DFS preoperative in BM (P = 0.036) and CVB (P = 0.042) | OSCC only | [81], 2003 |
| BM | HNSCC | 162 | RT-PCR: E48 mRNA | 40.0 | DTC on DFS (P = 0.1460) DMFS (P = 0.2912) N > or = 2 DMFS (P = 0.0210) | Various sites n = 13 OSCC n = 23 oropharyngeal | [80], 2004 | |
| BM | HNSCC | 176 | ICC: CK19 | 30.7 | OS and N-involvement (P = 0.0001), OS and DTC (0.0066) | Various sites n = 37 OSCC n = 43 oropharyngeal | [29], 2004 | |
| PB | HNSCC | 21 | Immunomagnetic separation: EpCAM | 33.3 | Occurrence of CTCs more frequent in stage III-IV than in stageI-II; connection with recurrence presumed; NS | Various sites n = 7 OSCC/ oropharyngeal | [83], 2007 | |
| PB | OSCC | 25 | RT-PCR: CK19 mRNA | 16 | Detection of CK19-mRNA when tumour is incised | OSCC only | [108], 2008 | |
| PB | HNSCC | 48 | Immunomagnetic separation: ICC: CK3-6H5 | 71 | DFS and NO CTC (P = 0.01) clinical outcome and CTCs (P = 0.04) | Various sites n = 25 OSCC n = 10 oropharyngeal | [30], 2010 | |
| PB | HNSCC | 42 | Flow cytometry: EpCAM, CD45 RT-PCR: EGFR mRNA | 43 | CTC and N in flow cytometry (P = 0.014), CTC and N in RT-PCR | Various sites n = 9 OSCC n = 17 oropharyngeal | [31], 2011 | |
| PB | HNSCC | 15 | CellSearch™ | 40 | CTC and M (P = 0.04) | Various sites n = 4 OSCC n =7 oropharyngeal | [84], 2012 | |
| PB | HNSCC | 31 | Flow cytometry: EpCAM; EGFR, CD45 | 29 pEGFR in 55% of CTC+-cases | Increasing number of CTC-positive cases at end of treatment | Various sites n =5 OSCC n =18 oropharyngeal | [50], 2012 | |
| PB | Under RCT HNSCC | 33 | Flow cytometry: EpCAM CD45 keratins 7, 8 EGFR | 33 pEGFR in 36.4% of CTC+-cases | None given for comparing two methods | Various sites n = 0 OSCC (not specified) n = 13 oropharyngeal | [51], 2012 | |
| PB | HNSCC | 73 | CellSearch™ | 15.1 | Decreasing CTC counts and clinical response (P = 0.017) | Various sites n = 3 OSCC n = 39 oropharyngeal | [82], 2012 | |
| BM | HNSCC | 105 | ICC: keratins 8, 18 and 19 | 14.5 | No significance for DTCs (76/105 tested) | Various sites n = 72 OSCC n = 8 oropharyngeal | [68], 2012 | |
| PB BM | OSCC | 110 | CellSearch™ ICC: keratins 8, 18 and 19 | 12.5 (Cell search) | 20.0 (ICC) | CTCs and T (P = 0.04), N and DTCs (P = 0.02), M and CTCs (P = 0.004), M and DTCs (P = 0.005), DTCs and RFS (P < 0.001) | OSCC only | [35], 2014 |
BM: Bone marrow aspirates; CD: Cluster of differentiation; CK: Cytokeratin; CTC: Circulating tumour cell; CVB: Central venous blood; DFS: Disease-free survival; DMFS: Distant metastasis free survival; EGFR: Epidermal growth factor receptor; pEGFR: Phospho-EGFR; HNSCC: Head neck squamous cell cancer; EpCAM: Epithelial cell adhesion molecule; M: Metastatic; NS: Nodal status; OS: Overall survival; OSCC: Oral squamous cell cancer; PB: Peripheral blood; RT-PCR: Reverse transcriptase-polymerase chain reaction; RFS: Relapse-free survival; T: Tumour stage; ICC: Immunocytochemistry; RCT: Randomized control trial; DTC: Disseminated tumour cells.