Background: Previous studies identified cadherin-17 (CDH17) as one of the most upregulated genes in node-positive gastric cancer. However, the prognostic significance of CDH17 in pN0 gastric cancer and its association with lymph node micrometastasis (LNMM) have not been investigated.
Methods: Clinicopathologic features of 191 patients with node-negative gastric cancer were studied retrospectively. All dissected lymph nodes were immunostained by cytokeratin to detect micrometastasis. CDH17 and lymphatic invasion (LVI) in primary carcinoma were evaluated by immunostaining of monoclonal CDH17 and D2-40 antibody. Correlation of CDH17 with clinicopathologic characteristics was subsequently assessed. Risk factors of LNMM were analyzed by univariate and multivariate logistic regression. Cox's proportional hazard model was applied to investigate independent prognostic factors of pN0 gastric cancer. Overall survival rates of patients with positive and negative CDH17 were compared, stratifying by pT stage, Lauren grade, and LNMM status.
Results: CDH17 was observed in 126 patients (66.0%). Positive expression of CDH17 was significantly associated with the age, tumor size, pT, Lauren grade, LVI, and LNMM, and identified as one of the independent risk factors of LNMM. Negative predictors of pN0 gastric cancer included pT, Lauren grade, LNMM, and CDH17. Furthermore, in tumors of pT2-3, intestinal histotype, and negative-LNMM, the survival rate of patients with CDH17 was significantly lower than that of patients without CDH17.
Conclusions: CDH17 was positively associated with larger tumor size, deeper invasion, diffuse/mixed histotype, LVI, and LNMM, predicting a poor prognosis in pN0 gastric cancer. Additionally, CDH17 may also serve as a potential indicator of LNMM.