The pretreatment plasma levels of both CK18–Asp396 and CK18 were significantly higher (P=0.015 for patients with gastric cancer and P<0.001 for patients with oesophageal and colorectal cancer) in the plasma samples of patients with all types of gastrointestinal adenocarcinoma examined compared with plasma samples from healthy volunteers (Figure 1 and Table 2). The gene discussed is KRT18; the disease is gastric cancer.