Fig. 5
a The resected specimen was 1.5 cm in diameter. b Histological findings of the metastatic mediastinal lymph node demonstrate moderately differentiated adenocarcinoma, indicating that it was a metastasis of gastric cancer (hematoxylin and eosin staining, magnification, × 400). c, d Both the primary tumor and the mediastinal node exhibited partially positive immunohistochemical staining for CK7 (data not shown) and positive immunohistochemical staining for CK20 (c: primary tumor, d: mediastinal node, magnification, × 5)