Expression of CDX-2 and ALK in primary gastric carcinoma

Background Gastric carcinoma still represents a serious health problem. Prognostic biomarkers that predict the disease outcome and aid in better treatment options are of great value. Intestinal differentiation marker, caudal type homeobox-2 ( CDX-2 ), and tumorigenic marker, anaplastic lymphoma kinase ( ALK ), may have influence on tumor behavior and prognosis. Aim The aim of this study was to analyze the expression of CDX-2 and ALK in relation to Her-2 status and clinicopathological factors of gastric carcinoma to assess the prognostic significance of combined biomarkers expression. Materials and methods Immunohistochemical expression of CDX-2 and ALK was studied in 68 paraffin-embedded specimens of primary gastric carcinoma. Results CDX-2 and ALK expressions were detected in 58.5 and 11.8% of studied cases, respectively. CDX-2 expression was significant in intestinal type tumors ( P =0.0001). A significant negative correlation was found between CDX-2 expression and tumor differentiation ( P =0.003), pT stage ( P =0.0001), lymph node metastasis ( P =0.005), and Her-2 expression ( P =0.042), whereas ALK expression was significantly more in diffuse type ( P =0.023). A significant positive correlation was observed between ALK -positive tumors and degree of tumor differentiation ( P =0.006), lymph node metastasis ( P =0.011), and Her-2 expression ( P =0.029). A significant negative relation was detected between CDX-2 and ALK expressions ( P =0.039). Conclusion Combined expressions of CDX-2 and ALK in gastric carcinoma allow the classification of patients into groups with different prognosis, clinical outcomes, and treatment options. CDX-2 + / ALK − cases were significantly associated with favorable prognostic factors.