The concentrations of CFD in stage I, II and III  ̃ IV GC patients were 785.46 ng/ml (395.05–1616.85 ng/ml), 1483.01 ng/ml (747.08–2430.86 ng/ml) and 1700.26 ng/ml (820.94–3739.02 ng/ml) respectively. Here, CFD is linked to gastric cancer.