Figure D . A histological overview in cross-section of this tumor was limited to the intramucosal layer. Figure E . Cancerous glands show an intramucosal growth and submucosal fibrosis for biopsy can be seen in the center of the lesion. Figure F .
Histological feature shows well to moderately differentiated adenocarcinoma.
With recent progress in electronic endoscopy, superficial depressed type cancers of large intestine have been often detected in Japan. These lesions are frequently malignant and also tend to invade the submucosal layer even in small sized lesions. In this case, the lesion has converging folds and the size is more than 10 mm in diameter. In addition, the depression contains an area of nodulation. It is difficult to distinguish the difference whether these findings were occurred by cancerous invasion or submucosal fibrosis due to the biopsy.