Figure 3: The number of circulating tumour cells (CTCs) can differentiate oesophageal cancer patients and its impact on survival.

The method of circulating tumour cell (CTC) detection can differentiate healthy individuals from patients with advanced oesophageal cancer with a P value of 0.04 using the Mann-Whitney U test (Panel A). Panels B and C show that patients with a lower pre-treatment CTC number have longer disease-specific progression-free survival or overall survival. Given the CTC status (score zero for CTC number less than 21.0 cells/mL; 1 for CTC number ≥ 21.0 cells/mL) and response after concurrent chemoradiotherapy (CCRT, score zero for complete remission; 1 for partial response; 2 for stable disease, and 3 for progressive disease), the summation of the CTC score and the score of response to CCRT is defined as the circulating tumour cell plus response (CTCR) score, and this score highly correlates with overall survival with a log rank test P value of <0.0001.