Background: Although lymph node involvement is an important prognostic factor for survival in patients with esophageal carcinoma, little is known about lymphangiogenesis in esophageal carcinoma. Podoplanin, a mutin-type transmembrane glycoprotein, specifically recognizes the lymphatic endothelium and is used as a lymphatic-specific marker. Anti-human podoplanin antibody was therefore used to quantify and evaluate the lymphangiogenesis in esophageal carcinoma.
Patients and methods: Lymphatic endothelial cells were detected by immunohistochemistry using mouse monoclonal anti-human podoplanin antibody. The relationship between lymphatic microvessel density (LMVD) and lymphatic vessel invasion (LVI), clinicopathological factors and the prognosis in 29 patients with esophageal carcinoma was investigated.
Results: LMVD was significantly higher in esophageal carcinoma patients who had any of the following characteristics: T3-T4 (p=0.0370), tumors more advanced than stage III (TNM staging) (p=0.0351), lymphatic invasion (p=0.0095) and LVI (+) (p=0.0016). LVI significantly correlated with lymph node metastasis (p=0.0003), TNM staging (p=0.0182) and LMVD (p=0.0388). The survival rate of patients with a low LMVD tended to be higher than that of patients with a high LMVD (5-year survival rate, 62.5% vs. 29.4%, p=0.0832).
Conclusion: The evaluation of lymphangiogenesis using podoplanin immunohistochemistry may be useful in predicting lymph node metastasis and the prognosis in patients with esophageal carcinoma.