Fig. 4
a Adenocarcinoma cells with glandular formation and agglutination are observed. (Hematoxylin & Eosin staining × 100). b Intercellular bridges are observed in cancer cells with solid growth. The tumor was diagnosed as squamous cell carcinoma. (Hematoxylin & Eosin staining × 100). c A transition between adenocarcinoma and squamous cell carcinoma can be seen. This strongly suggests that the squamous cell carcinoma had arisen from adenocarcinoma. (Hematoxylin & Eosin staining × 100). d Atypical cells are polygonal and strongly stained with orange G, indicating nuclear concentration. These findings suggest the cells to be atypical and to be derived from squamous cell carcinoma. (Papanicolaou staining × 100)