Clinical significance of immunohistochemically-identified lymphatic and/or blood vessel tumor invasion in gastric cancer

Background: Tumor invasion and lymph node metastasis are significant prognostic factors for gastric cancer, and lymphatic and vascular tumor invasion are also significant risk factors for gastric cancer recurrence. Recently, the immunohistochemical detection of lymphatic and blood vessel tumor invasion (LBVI) has been shown to have a higher sensitivity and specificity than hematoxylin-eosin staining methods. Materials and Methods: One hundred forty-nine gastric cancer patients who underwent curative resection at Korea University Hospital between November 2003 and December 2006 served as the study subjects. Lymphatic vessel invasion was evaluated by immunostaining with the new selective marker, D2-40, and blood vessel invasion was assessed with anti-CD31 antibody. Patients were divided according to the presence of LBVI, clinicopathologic factors were compared, and postoperative surgical outcomes were analyzed. Results: LBVI was present in 66 patients (44.3%). LBVI was significantly correlated with depth of tumor invasion(P < 0.001), lymph node stage(P < 0.001), and lymph node micrometastasis (P = 0.013). Cancer recurrence was more commoninthe LBVI group(P = 0.007), and peritoneal seeding was the most prevalent type of recurrence (P = 0.028). Univariate analysis showed tumor size, depth of tumor invasion, lymph node stage, and LBVI to have a significant impact on survival. Based on multivariate analysis, however, depth of tumor invasion and lymph node stage were correlated with survival. Conclusion: Immunohistochemical demonstration of LBVI is an additional prognostic marker, and provides useful information for planning treatment strategies in gastric cancer patients.