Significance of MUC1 expression in biopsy specimens of submucosal invasive gastric carcinoma: The association with lymph node metastasis.

Mucin 1, cell surface associated (MUC1) is a tumor-associated glycoprotein that has been reported to have an important role in lymphatic invasion and metastasis. The present study aimed to investigate the significance of MUC1 expression in endoscopic biopsy specimens of submucosal invasive gastric carcinomas and the association with lymph node metastasis. The clinicopathological features of 144 cases of surgically resected submucosal invasive gastric carcinomas and their paired endoscopic biopsy specimens were reviewed. Immunohistochemical staining for MUC1 was performed for the 144 endoscopic biopsy specimens. Positive MUC1 expression was identified in 70 (49%) cases. In addition, univariate analysis revealed that MUC1 expression was significantly associated with the presence of poorly-differentiated (P=0.001) and poorly-cohesive (P=0.015) carcinoma cells, undifferentiated type by Japanese classification (P<0.001), diffuse type of Lauren classification (P<0.001) and lymph node metastasis (P=0.024). By multivariate analysis, diffuse type of Lauren classification (P<0.001) and lymph node metastasis (P=0.035) were identified as independent factors for MUC1 expression. Furthermore, MUC1 expression (P=0.007), tumor size (P=0.018) and lymphatic invasion (P<0.001) were demonstrated to be independent factors for lymph node metastasis under multivariate analysis. In conclusion, the results of the present study indicated that positive MUC1 expression in endoscopic biopsy specimens may be a predictive factor of lymph node metastasis in submucosal invasive gastric carcinoma.