We assessed the presence of micrometastases in SNs of gastric cancer by using multiple-marker RT–PCR and Southern blot assay with the markers CK-18 (Brown et al, 1995), CEA (Mori et al, 1995), hTRT (Takakura et al, 1998), and MUC-1 (Noguchi et al, 1994). Here, KRT18 is linked to gastric cancer.