Malignant colorectal polyps

Figure 2 Kitajima’s classification. The method used for measurement of submucosal invasion (SM) depth. A: For pedunculated submucosal invasive colorectal carcinoma, level 2 according to Haggitt’s classification was used as the baseline (grey line), and SM depth was measured as the vertical distance from this line to the deepest portion of invasion; B: For nonpedunculated, when the muscularis mucosae could be identified in HE stained specimens, the muscularis mucosae was used as baseline (grey line) and the vertical distance from this line to the deepest portion of invasion represented with bidirectional arrow grey; C: For nonpedunculated, when the muscularis mucosae could not be identified due to carcinomatous invasion, the superficial aspect of the invasive carcinoma was used as baseline (grey line), and the vertical distance from this line to the deepest portion of invasion was determined (bidirectional arrow grey).