Histopathological and genetic differences between polypoid and non-polypoid submucosal colorectal carcinoma

Figure 1 A: Macroscopic appearance of PG submucoal invasive early colorectal carcinoma, note the polyp-like exophytic from of the lesion; B: Microscopic appearance of PG submucoal invasive early colorectal carcinoma, note the intramucosal protruding proliferation (arrow head).

Figure 2 A: Macroscopic appearance of NPG and PG submucoal invasive early colorectal carcinoma, note the depressed from of the lesion (arrow head); B: Microscopic appearance of PG submucoal invasive early colorectal carcinoma, no intramucosal protruding proliferation in the lesion.

Figure 3 p53 immunohistochemical staining in NPG submucosal invasive early colorectal carcinomas (× 200). Note positive staining of p53 in cancer tissue (arrows), the picture on the left side is the same section of HE staining.

Figure 4 SSCP analysis of the K-ras gene codon 12 in PG submucosal invasive early colorectal carcinomas, note two extra bands of point mutations (arrow head). C: normal control; T: polypoid submucosal colon cancer; M: molecular marker.