Histological Differences between Vascular and Mucosal Hemorrhoids

PURPOSE: The aim of this study is to compare and analyze the histological differences between vascular and mucosal hemorrhoids, two structurally different types of hemorrhoids. METHODS: Internal hemorrhoidal tissue samples were fixed in 10% Formalin solution, and coronal sections included 10-mm proximal and 5-mm distal of the dentate line. Routine Masson-Trichrome and H&E were performed to evaluate the thickness of the mucosa and changes in the structure and the densities of submucosal vessels, connective tissue, and muscle. RESULTS: Compared with the corresponding tissues of mucosal hemorrhoids, the submucosal connective tissue and perivascular connective tissue of vascular hemorrhoids showed a loosened density, severe fragmentation, and an irregular arrangement. The submucosal vascular dilatation was more frequent and more severe in vascular hemorrhoids, but the number of vessels between both types of hemorrhoids did not show much difference. Hypertrophy and regular arrangement of the submucosal muscles were observed more frequently in the mucosal than in the vascular hemorrhoids. CONCLUSION: Compared to mucosal hemorrhoids, vascular hemorrhoids showed augmented damage in submucosal connective tissue and intense dilatation of vessels with a thinner mucosa. On the other hand, compared to vascular hemorrhoids, mucosal hemorrhoids showed hypertrophy of submucosal muscle and relatively minor alterations in vessels with a thicker mucosa. These histological differences may provide the basis for different etiologies between vascular and mucosal hemorrhoids.

Clinical Significance of E-cadherin and beta-catenin Complex Expression in T2 Colorectal Cancer

PURPOSE: Expression of adhesion molecules is significantly correlated with the invasion and the metastasis of colorectal cancer. The aim of this study is to identify the importance of the expressions of E-cadherin and beta-catenin as a prognostic factor in T2 colorectal cancer. METHODS: Forty-five cases of primary T2 colorectal cancers were selected between February 1997 and February 2000. We evaluated the membranous expressions of E-cadherin and beta-catenin by using immunohistochemisty and analyzed the relationship with various clinicopathologic parameters. RESULTS: Loss of membranous E-cadherin was significantly associated with histologic differentiation (P=0.023), vascular invasion (P<0.001), lymphatic invasion (P<0.001), and lymph-node metastases (P=0.001). Similar patterns were observed in the expression of beta-catenin. The correlation between the E-cadherin and the beta-catenin expressions was statistically significant (P<0.001). In the multivariate analysis, neither the loss of expression of E-cadherin nor beta-catenin is a risk factor affecting lymph-node metastasis in T2 colorectal cancers. However, there were significant differences in the 5-year disease-free survival rates between the positive (+/-, +) and the negative (-) expression groups of E-cadherin and beta-catenin (P=0.015, 0.03). CONCLUSIONS: This study suggests that loss of membranous expression of E-cadherin and beta-catenin molecules correlates with poor prognostic factors and indicates invasion and metastasis in T2 colorectal cancer, which, therefore, might be predictive of short survival in these patients.