MUC1 and cathepsin D expression in early colorectal carcinoma showing V type pit pattern.

The relation between MUC1, cathepsin D expression, and histologic features in early colorectal carcinomas (CRCs) with V type pit pattern was examined in 78 patients. We classified V type pit pattern into two grades (VA, VN) and we subclassified the VN type pit pattern into three subtypes (Grade A, B, and C) according to the degree of appearance of VN type pit pattern. At the tumor surface, the status of desmoplastic reaction and pit disorder or destruction were subclassified histologically into three grades (-, +, ++). MUC1 and cathepsin D expression were examined immunohistochemically at a superficial level and at the deepest part of the tumor invasion. MUC1 expression showed a significant correlation with high grade carcinoma, desmoplastic reaction (+) levels in VA type pit pattern (P<0.05), and high grade carcinoma, sm2 and sm3 lesions, desmoplastic reaction (+) and (++) levels, pit disorder or destruction (+) and (++) levels in VN type pit pattern (P<0.05). Cathepsin D expression had a significant correlation with m and sm1 lesions and desmoplastic reaction (-) levels in VN type pit pattern (P<0.05). In VA type pit pattern, a significant correlation between cathepsin D expression and histologic findings was absent. The incidence of MUC1 expression in VN.Grade B and C type pit pattern was significantly higher than that in VA and VN.Grade A type pit pattern (P<0.05). The incidence of cathepsin D expression in VA, VN.Grade A and B type pit pattern was significantly higher than that in VN.Grade C type pit pattern (P<0.05). MUC1 expression (+) or (++) levels at the deepest part of a tumor was identical to that (+) or (++) levels at the superficial part except for one case. Cathepsin D expression at the deepest part of a tumor differed from that at the superficial part. Desmoplastic reaction may be related to MUC1 and cathepsin D expression; however, pit disorder or destruction may be related to only MUC1 expression in V type pit pattern. MUC1 expression at the superficial part of a tumor may be related to expression at the deepest part; however, cathepsin D expression at the superficial part may not be related to expression at the deepest part in submucosal CRCs with V type lesions.