Extremely well-differentiated adenocarcinoma of the stomach: Clinicopathological and immunohistochemical features

Figure 1 Extremely well-differentiated adenocarcinoma of the stomach, gastric-type (case 4). A: Macroscopic view showing a polypoid lesion with an irregular surface; B: cancer invasion of the whole thickness of the gastric wall (low-power view); C: carcinoma mimicking the normal gastric foveolar epithelium with basally located small nuclei (hyperchromatic nuclei) and abundant mucin; D: papillary projections occasionally seen in the carcinomatous glands; E: diffuse positive staining of human gastric mucin in carcinomatous glands; and F: focally positive staining of MUC6 in carcinomatous glands.