Predictors of lymph node metastasis in T1 colorectal carcinoma: an immunophenotypic analysis of 265 patients.

The appropriateness of endoscopic resection in patients with T1 colorectal carcinomas is unclear. Highly precise predictors of lymph node metastasis are required to optimize the outcomes of treatments for T1 colorectal carcinomas. The purpose of this work was to identify predictors of lymph node metastasis by examining the clinicopathologic significance of immunophenotypes found in T1 colorectal carcinomas. This was a retrospective study. The study was conducted at a university hospital. Included were 265 patients with T1 colorectal carcinoma who underwent radical surgery. Patients with T1 colorectal carcinoma were managed. Immunophenotypes were associated with various clinicopathologic parameters, and CD10 expression was strongly associated with lymph node metastasis. The levels of MUC2, MUC5AC, and CD10 expression were individually significantly associated with tumor location, growth pattern, histologic type, invasive potential, and metastatic potential. The incidence of lymph node metastasis was significantly associated with each of the 5 following parameters: depth of submucosal invasion (p = 0.005), tumor budding (p < 0.001), lymphatic invasion (p < 0.001), MUC2 expression (p = 0.006), and CD10 expression (p < 0.001). Multivariate analysis showed that CD10 expression (OR, 9.2 [95% CI, 2.5-39.8]; p = 0.001) and lymphatic invasion (OR, 6.3 [95% CI, 2.5-17.7]; p < 0.001) were independently associated with lymph node metastasis. This study was limited by its small sample size, intraobserver variation attributed to immunohistochemical staining, and potential selection bias because surgically resected specimens were collected instead of endoscopically resected specimens. We suggest that CD10 expression is closely associated with lymph node metastasis in T1 colorectal carcinoma.