Clinicopathologic Factors for Prediction of Lymph Node Metastasis in Submucosally Invasive Colorectal Carcinoma

Purpose: The purpose of this study is to identify useful clinicopathologic factors for the prediction of lymph node metastasis in submucosally invasive colorectal carcinoma. Methods: A total of fifty-four cases of colorectal carcinomas with submucosal invasion were included. The patients underwent curative resection with en bloc lymph node dissection. Clinical features such as age, gender, tumor size and tumor location were reviewed. Histopathologic examinations for tumor growth type, differentiation, depth of tumor invasion, lymphovascular invasion, neural invasion, tumor budding and peritumoral inflammation were performed. The expression of E-cadherin, β-catenin, Smad4, p53 and Ki-67 were examined by immunohistochemistry. The correlation between the clinicopathologic factors and lymph node metastasis was evaluated. Results: From the 54 patients with submucosally invasivecolorectal carcinoma, lymph node metastasis was identified in 13 cases (24.1%). The incidence of lymph node metastasis was significantly higher in cases positive for lymphovascular invasion (55.6% vs. 17.8%, P=0.028) and positive for tumor budding (47.4% vs. 11.45%, P=0.006). Cases negative for Smad4 had a higher tendency for incidence of lymph node metastasis (28.6% vs. 15.8%, P=0.341). Other clinicopathologic and immunohistochemical features were irrelevant to the lymph node status. In multivariate analysis, only tumor budding was an independent predictor of lymph node metastasis (P=0.051). Conclusion: Lymphovascular invasion and tumor budding were predictive factors of lymph node metastasis in submucosally invasive colorectal carcinoma. The incidence of lymph node metastasis of submucosally invasive colorectal carcinoma was not low. Careful selection for avoiding surgery in submuocally invasive colorectal carcinoma should be considered.