Epithelial-mesenchymal transition phenotype is associated with patient survival in small intestinal adenocarcinoma

Aims: We investigated the clinical significance of epithelialmesenchymal transition (EMT) phenotype in 184 small intestinal adenocarcinomas (SIACs) based on the expression pattern of EMT-related proteins in cancer cells. Methods: Immunohistochemistry for epithelial (E-cadherin) and mesenchymal (vimentin and fibronectin) markers were performed and cases of SIAC were classified into four subtypes of EMT: complete type (E-cadherin-, vimentin+ and/or fibronectin+), wild type (E-cadherin+, vimentin-, fibronectin-), incomplete 1 type (hybrid type; E-cadherin+, vimentin+ and/or fibronectin+), and incomplete 2 type (null type; E-cadherin-, vimentin-, fibronectin+). Results: We identified 19 (10.3%) cases of complete EMT type, 86 (46.7%) cases of wild type and 79 (43%) cases of incomplete EMT type [hybrid type, 22 (12%) cases; null type, 57 (31%) cases]. Complete EMT phenotype showed a significant association with undifferentiated histology ( p<0.001). Overall survival of SIAC patients with complete EMT phenotype was significantly shorter than those of patients with incomplete ( p=0.001) and wild ( p<0.001) types. In multivariate analysis, complete EMT phenotype was an independent prognostic factor in SIAC patients (hazard ratio 2.3; 95% confidence interval 1.15-4.6; p=0.019). Conclusion: Complete EMT phenotype stratifies a specific group representing a poor clinical outcome in patients with SIAC.