The immunohistochemical expression of E-cadherin in gastric cancer; correlations with clinicopathological factors and patients' survival

Background: The aim of our study is to investigate the immunohistochemical expression of E-cadherin in gastric carcinomas and in surrounding mucosa (normal or with lesions of chronic atrophic gastritis, intestinal metaplasia or dysplasia). Material and Methods: We included 61 patients with gastric cancers operated in Emergency County Hospital Timisoara. We analyzed the E-cadherin immunohistochemical expression, the correlation with clinical and pathological factors and the outcome of the patients. The positive homogeneous pattern of staining for the cellular membranes is considered normal. The negative homogeneous or the heterogeneous pattern (of the cytoplasm and membrane) represented aberrant E-cadherin expression. Results: Areas of chronic atrophic gastritis and intestinal metaplasia presented a normal pattern of immunostaining for the membranes. Aberrant E-cadherin expression was noticed in 30 cases of gastric carcinomas (49.2%) and in 11 cases (35.5%) of epithelial dysplasia in the surrounding tissue. Our results showed no correlation between E-cadherin expression and gender, age, tumor location, pT, pN, pTNM and lympho-vascular invasion. Aberrant E-cadherin immunostainings were significantly more frequent in diffuse-type carcinomas in comparison with the intestinal-type carcinomas (82.4% vs. 31.6%) (p = 0.000491 ES). Signet-ring carcinomas and anaplastic carcinomas presented a high-proportion of aberrant immunostainings (82.4% and 100%), as well as poor differentiated carcinomas (61.5%). Carcinomas with distant metastasis presented significantly more aberrant immunostainings than those without metastasis (71.4% vs. 42.6%). Five-year survival rate was significantly lower in patients with aberrant E-cadherin expression in comparison with the patients presenting normal staining (10% vs. 22.6%). Conclusions: In gastric carcinomas and areas of epithelial dysplasia, aberrant E-cadherin expression was significantly more frequent in comparison with the surrounding normal mucosa (p<0.001 ES). Our data suggest a strong correlation between Lauren's classification of gastric carcinomas and E-cadherin immunohistochemical expression. Assessment of the survival curve of the patients highlighted the role of prognostic factor for the aberrant immunohistochemical E-cadherin expression.