AB13. Study the relationship between CLEVER-1/Stabilin-1 positive macrophage and LVD, prognosis in gastric cancer

Backgrounds and objectives: Lymph node metastasis is an important prognostic factor for gastric cancer. The pre-existing data suggests that more than 80% of the advanced gastric cancer patients develop lymph node metastasis. And the 5-years survival rate of the patients without lymph node metastasis is 3 times more than those with lymph node metastasis. It is well known that lymphangiogenesis happens in tumor environment, and the first-way for gastric cancer cells to disseminate is lymphatic vessel. Recent studies suggested that macrophage promoted cancer lymphangiogenesis and lymph node metastasis. Common lymphatic endothelial and vascular endothelial receptor-1 (CLEVER-1) is a molecule regulating lymphocyte migration into the lymphatics and leukocytes’ entrance to sites of inflammation, expressing in some macrophages. The present study investigates whether the CLEVER-1 positive macrophages express in gastric cancer, and the relation between the CLEVER-1 positive macrophages and lymphangiogenesis, the prognosis of gastric cancer, which may provide clinical data for the following research.

Methods: 85 primary human gastric cancer patients before 2006 in 301 hospital were studied. These cases were investigated by immunohistochemical staining for D2-40 and Stabilin-1 antibody. The relation between positive-macrophage, LVD, LN metastasis and other clinical parameters was studied.

Results: The peritumoral lymphatic vessel density is bigger than intratumoral. The factors such as tumor differentiation, depth of invasion, tumor size, lymph node metastasis, cancer embolus are associated with lymphatic vessel density, while age and gender are not. We can suspect gastric cancer with lymph node metastasis when the peritumoral lymphatic vessel density is more than 14.50. The sensitivity is 90.7%, and the specificity is 61.3%. The mainly Stabilin-1/CLEVER-1--positive macrophage is in tumor tissues, while less in normal tissues. T stage, N stage and cancer embolus are related to Stabilin-1/CLEVER-1--positive macrophage, while age, tumor size, differentiation and the location are not. There is a correlation between the peritumoral LVD and Stabilin-1/CLEVER-1--positive macrophage.

Conclusions: The Stabilin-1/CLEVER-1--positive macrophage is an important parameter for prognosis of gastric cancer.

Keywords: Gastric cancer; lymphangiogenesis; Stabilin-1/CLEVER-1