Fig 1.
Flowchart of study selection process.
CTC: circulating tumor cells, HNSCC: head and neck squamous cell carcinoma.
Table 1.
Characteristics of studies included in the final analyses.
Fig 2.
Forest plots illustrating prognostic value of CTC detection on the overall and recurrence-free survivals in HNSCC patients.
HR: hazard ratio, 95%CI: 95% confidence interval.
Fig 3.
Funnel plots of analyzed studies according to the overall and recurrence-free survivals.
SE: standard error, HR: hazard ratio.