Fig. 4

Histopathological study of filiform polyposis and adenocarcinoma (hematoxylin-eosin and p53-immunohistochemistry staining). Histopathological findings revealed that the worm-like polyps were filiform polyposis; dilated blood vessels, fibrovascular cores, and infiltrated neutrophils and lymphoid cells were seen in submucosal tissue of the polyp axis (a, × 5). Furthermore, well-differentiated to moderately differentiated tubular adenocarcinoma developed on the filiform polyposis. They mostly existed in the intramucosal area and were scattered uniformly on the surface of filiform polyposis (asterisks). The square part of Fig. 4a. The adenocarcinoma developed in the intramucosal area of the filiform polyposis (b, × 50). Immunohistochemistry using anti-p53 verified that the normal mucosa of filiform polyposis absence of abnormal p53 expression, while the adenocarcinoma on filiform polyposis showed an abnormal p53 nuclear expression (c, × 50)