Histopathological phenotypes of early gastric cancer and its background mucosa.

Recent advances in endoscopic submucosal dissection (ESD) techniques contribute to endoscopic treatment of early gastric cancer (EGC). Recognition of chronic atrophic gastritis as the background is important for high-quality detection and diagnosis of EGC. But, relationships between EGC and atrophy of the background gastric mucosa caused by Helicobacter pylori are not well understood. The present study demonstrated histopathological phenotypes of EGC, as well as chronic atrophic gastritis as background mucosa of EGC. We evaluated mucosal heights, number of glands, and degree of intestinal metaplasia (IM) of the background gastric mucosa, using 81 cases of EGC resected by ESD. Gastric phenotype cancer cases showed IM of the background gastric mucosa less frequently, compared with intestinal phenotype cancer cases (score of IM, 1.15 vs. 1.65, P = 0.012). The average mucosal heights around EGC were lower in moderately to poorly differentiated adenocarcinoma cases than well differentiated adenocarcinoma cases (442.6 µm vs. 500.2 µm, P = 0.011). The mucosal atrophy indicated by average heights of background mucosa was low in the gastric phenotype cancer cases, compared with the intestinal phenotype cancercases (452.8 µm vs. 505.6 µm, P = 0.018). In the fundic gland area, the mucosal heights were low in the gastric phenotype cancer cases, compared with the intestinal phenotype cancer cases (413.2 µm vs. 495.5 µm, P = 0.015). Our results using EGC specimens indicated that gastric phenotype cancer and moderately to poorly differentiated adenocarcinoma had atrophic background mucosa with lower mucosal heights and less IM. The atrophic gastric mucosa with less IM is thought to play an important role in gastric carcinogenesis, especially tumoriogenesis of gastricphenotype cancer.

L1 Cell adhesion molecule (L1CAM) expression at the cancer invasive front is a novel prognostic marker of pancreatic ductal adenocarcinoma.

BACKGROUND AND OBJECTIVES: Pancreatic ductal adenocarcinoma (PDAC) is one of the most extremely aggressive cancers with a poor prognosis after curative resection. L1 cell adhesion molecule (L1CAM) is a 200-220 kDa type I transmembrane glycoprotein of the immunoglobulin superfamily, which has been shown to affect the prognosis of several cancers. No clinicopathological significance of L1CAM expression has been examined at the invasive front of PDAC. In this study, we examined the relationship between L1CAM expression and clinicopathological features in PDAC by immunohistochemistry. METHODS: One hundred seven surgically resected specimens of PDAC were immunohistochemically examined using a monoclonal antibody against L1CAM. RESULTS: Positive expression of L1CAM was found in 23 of 107 cases with PDAC. In most cases (21/23), L1CAM expression was localized at the invasive front of the tumor tissue. Positive expression of L1CAM was significantly correlated with the histological grade, lymph node involvement, and distant metastasis. In univariate analysis, a positive expression of L1CAM was associated with short overall survival (P = 0.0002), and this was significant in multivariate analysis (P = 0.009). CONCLUSIONS: L1CAM could play an important role in the invasive process in vivo, and is thought to be a good indicator of prognosis in PDAC.

Vimentin expression of esophageal squamous cell carcinoma and its aggressive potential for lymph node metastasis.

Esophageal squamous cell carcinoma (ESCC) has been generally considered as one of the most aggressive cancers with poor prognosis. Vimentin is the major protein constituent of intermediate filaments in normal and neoplastic mesenchymal cells, and has been regarded as a marker of epithelial-mesenchymal transition (EMT). However, little is known about ESCC with vimentin expression as a marker of EMT. In this study, we analyzed vimentin expression in 129 cases of ESCC in order to elucidate whether vimentin expression is correlated with clinicopathological features and aggressive behavior of ESCC. Vimentin expression was identified in 96 of the 129 cases (74.4%). The cases with vimentin-positive carcinoma cells showed a significantly higher incidence of lymph node metastasis (P = 0.001). Carcinomas with vimentin expression were more advanced in terms of tumor status and lymphatic invasion (P = 0.001, P = 0.009, respectively), and associated with stronger stromal alpha-smooth muscle actin (alpha-SMA) expression (P < 0.001). Vimentin expression was also associated with distant metastasis, including distant node metastasis (P = 0.014). Vimentin expression in both primary and metastatic carcinomas was found in 68.6% (48/70) of the cases, while no vimentin expression in both primary and metastatic carcinomas comprised 92.3% of the cases (12/13) (P < 0.001). In conclusion, we demonstrated that vimentin expression in ESCC is an independent predictor of lymph node metastasis (multivariate analysis, P = 0.014, odds ratio: 3.314, 95% confidence interval: 1.276-8.605). In addition, vimentin expression was frequently retained in metastatic carcinoma of the lymph node.

Expression of syndecan-1 and E-cadherin is inversely correlated with poor patient's prognosis and recurrent status of extrahepatic bile duct carcinoma.

Extrahepatic bile duct carcinoma is one of the most extremely aggressive cancers with poor prognosis after curative resection. Syndecan-1 and E-cadherin are transmembrane glycoproteins, and have important roles in cell-cell adhesion and tumor progression. In this study, we examined 84 surgically resected cases of extrahepatic bile duct adenocarcinoma to clarify clinicopathological significance of syndecan-1/E-cadherin expression. Reduced expressions of syndecan-1 and Ecadherin were found in 69.0% (58/84) and 46.4% (39/84) of the bile duct carcinomas. Reduced syndecan-1 expression was correlated with lymphatic/venous/nervous invasion (P < 0.0001), and was associated with short overall survival (P = 0.0002). Reduced E-cadherin expression was correlated with lymphatic and nervous invasion (P = 0.008, P < 0.0001, respectively), and was associated with short overall survival (P = 0.0038). The results indicated that reduced syndecan-1/E-cadherin expression may be good indicators of recurrence and prognosis in extrahepatic bile duct carcinoma.